Search results for: innate immune
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 791

Search results for: innate immune

401 Application of Host Factors as Biomarker in Early Diagnosis of Pulmonary Tuberculosis

Authors: Ambrish Tiwari, Sudhasini Panda, Archana Singh, Kalpana Luthra, S. K. Sharma

Abstract:

Introduction: On the basis of available literature we know that various host factors play a role in outcome of Tuberculosis (TB) infection by modulating innate immunity. One such factor is Inducible Nitric Oxide Synthase enzyme (iNOS) which help in the production of Nitric Oxide (NO), an antimicrobial agent. Expression of iNOS is in control of various host factors in which Vitamin D along with its nuclear receptor Vitamin D receptor (VDR) is one of them. Vitamin D along with its receptor also produces cathelicidin (antimicrobicidal agent). With this background, we attempted to investigate the levels of Vitamin D and NO along with their associated molecules in tuberculosis patients and household contacts as compared to healthy controls and assess the implication of these findings in susceptibility to tuberculosis (TB). Study subjects and methods: 100 active TB patients, 75 household contacts, and 70 healthy controls were taken. VDR and iNOS mRNA levels were studied using real-time PCR. Serum VDR, cathelicidin, iNOS levels were measured using ELISA. Serum Vitamin D levels were measured in serum samples using chemiluminescence based immunoassay. NO was measured using colorimetry based kit. Results: VDR and iNOS mRNA levels were found to be lower in active TB group compared to household contacts and healthy controls (P=0.0001 and 0.005 respectively). The serum levels of Vitamin D were also found to be lower in active TB group as compared to healthy controls (P =0.001). Levels of cathelicidin and NO was higher in patient group as compared to other groups (p=0.01 and 0.5 respectively). However, the expression of VDR and iNOS and levels of vitamin D was significantly (P < 0.05) higher in household contacts compared to both active TB and healthy control groups. Inference: Higher levels of Vitamin D along with VDR and iNOS expression in household contacts as compared to patients suggest that vitamin D might have a protective role against TB which prevents activation of the disease. From our data, we can conclude that decreased vitamin D levels could be implicated in disease progression and we can use cathelicidin and NO as a biomarker for early diagnosis of pulmonary tuberculosis.

Keywords: vitamin D, VDR, iNOS, tuberculosis

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400 Serological Screening of Cytomegalovirus Infection among Sudanese Patients with Leukemia, Breast and Prostate Cancers at Radiation-Isotope Center in Khartoum

Authors: Abuelquasim. M. Hassan, Namarig .S. Mohammed, Samah F. Mohammed, Wafaa. A. Mohammed, Wafaa M. Edriss, Amel A. Ahmed, Elfadil M. Abass

Abstract:

Introduction: Cytomegalovirus (CMV), a common virus, usually causes asymptomatic infections in immunocompetent hosts; however, it may lead to serious complications especially in cancer patients. Objectives: This study was conducted to determine the seroprevalence of human cytomegalovirus (HCMV) among leukemia, breast and prostate cancer patients attending at Radiation Isotope-Center-Khartoum (RICK) from April to August 2016. Material and Methods: A total of 91 subjects were included: 30 leukemic, 22 breast cancer and 29 prostate cancer patients.10 of them were healthy and used as control group, serum samples were collected and tested for CMV IgG & IgM using enzyme-linked immune sorbent assay (ELISA). Result: Of the control group, 9/10 (9.9%) were seropositive for CMV IgG and 1/10 (1.09%) were sero positive for IgM. Also, all cancer groups demonstrated presence of IgG antibody classes as: The percentage of positive results in prostate, breast cancer and leukemia were 35.8 %, 37.2%, and 35.3% respectively. Conclusion: There was no significant correlation between leukemia, breast, prostate and HCMV.

Keywords: cytomegalovirus, serodiagnostic, breast cancer, leukemia

Procedia PDF Downloads 352
399 Clinical Pathway for Postoperative Organ Transplants

Authors: Tahsien Okasha

Abstract:

Transplantation medicine is one of the most challenging and complex areas of modern medicine. Some of the key areas for medical management are the problems of transplant rejection, during which the body has an immune response to the transplanted organ, possibly leading to transplant failure and the need to immediately remove the organ from the recipient. When possible, transplant rejection can be reduced through serotyping to determine the most appropriate donor-recipient match and through the use of immunosuppressant drugs. Postoperative care actually begins before the surgery in terms of education, discharge planning, nutrition, pulmonary rehabilitation, and patient/family education. This also allows for expectations to be managed. A multidisciplinary approach is the key, and collaborative team meetings are essential to ensuring that all team members are "on the same page.". The following clinical pathway map and guidelines with the aim to decrease alteration in clinical practice and are intended for those healthcare professionals who look after organ transplant patients. They are also intended to be useful to both medical and surgical trainees as well as nurse specialists and other associated healthcare professionals involved in the care of organ transplant patients. This pathway is general pathway include the general guidelines that can be applicable for all types of organ transplant with special considerations to each organ.

Keywords: organ transplant, clinical pathway, postoperative care, same page

Procedia PDF Downloads 408
398 Dietary Gluten and the Balance of Gut Microbiota in the Dextran Sulphate Sodium Induced Colitis Model

Authors: Austin Belfiori, Kevin Rinek, Zach Barcroft, Jennifer Berglind

Abstract:

Diet influences the composition of the gut microbiota and host's health. Disruption of the balance among the microbiota, epithelial cells, and resident immune cells in the intestine is involved in the pathogenesis of inflammatory bowel disease (IBD). To study the role of gut microbiota in intestinal inflammation, the microbiome of control mice (C57BL6) given a gluten-containing standard diet versus C57BL6 mice given the gluten-free (GF) feed (n=10 in each group) was examined. All mice received the 3% DSS for 5 days. Throughout the study, feces were collected and processed for DNA extraction and MiSeq Illumina sequencing of V4 region of bacterial 16S rRNA gene. Alpha and beta diversities and compositional differences at phylum and genus levels were determined in intestinal microbiota. The mice receiving the GF diet showed a significantly increased abundance of Firmicutes and a decrease of Bacteroides and Lactobacillus at phylum level. Therefore, the gluten free diet led to reductions in beneficial gut bacteria populations. These findings indicate a role of wheat gluten in dysbiosis of the intestinal microbiota.

Keywords: gluten, colitis, microbiota, DSS, dextran sulphate sodium

Procedia PDF Downloads 183
397 A Longitudinal Case Study of Greek as a Second Language

Authors: M. Vassou, A. Karasimos

Abstract:

A primary concern in the field of Second Language Acquisition (SLA) research is to determine the innate mechanisms of second language learning and acquisition through the systematic study of a learner's interlanguage. Errors emerge while a learner attempts to communicate using the target-language and can be seen either as the observable linguistic product of the latent cognitive and language process of mental representations or as an indispensable learning mechanism. Therefore, the study of the learner’s erroneous forms may depict the various strategies and mechanisms that take place during the language acquisition process resulting in deviations from the target-language norms and difficulties in communication. Mapping the erroneous utterances of a late adult learner in the process of acquiring Greek as a second language constitutes one of the main aims of this study. For our research purposes, we created an error-tagged learner corpus composed of the participant’s written texts produced throughout a period of a 4- year instructed language acquisition. Error analysis and interlanguage theory constitute the methodological and theoretical framework, respectively. The research questions pertain to the learner's most frequent errors per linguistic category and per year as well as his choices concerning the Greek Article System. According to the quantitative analysis of the data, the most frequent errors are observed in the categories of the stress system and syntax, whereas a significant fluctuation and/or gradual reduction throughout the 4 years of instructed acquisition indicate the emergence of developmental stages. The findings with regard to the article usage bespeak fossilization of erroneous structures in certain contexts. In general, our results point towards the existence and further development of an established learner’s (inter-) language system governed not only by mother- tongue and target-language influences but also by the learner’s assumptions and set of rules as the result of a complex cognitive process. It is expected that this study will contribute not only to the knowledge in the field of Greek as a second language and SLA generally, but it will also provide an insight into the cognitive mechanisms and strategies developed by multilingual learners of late adulthood.

Keywords: Greek as a second language, error analysis, interlanguage, late adult learner

Procedia PDF Downloads 108
396 Broad Host Range Bacteriophage Cocktail for Reduction of Staphylococcus aureus as Potential Therapy for Atopic Dermatitis

Authors: Tamar Lin, Nufar Buchshtab, Yifat Elharar, Julian Nicenboim, Rotem Edgar, Iddo Weiner, Lior Zelcbuch, Ariel Cohen, Sharon Kredo-Russo, Inbar Gahali-Sass, Naomi Zak, Sailaja Puttagunta, Merav Bassan

Abstract:

Background: Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disorder that is characterized by dry skin and flares of eczematous lesions and intense pruritus. Multiple lines of evidence suggest that AD is associated with increased colonization by Staphylococcus aureus, which contributes to disease pathogenesis through the release of virulence factors that affect both keratinocytes and immune cells, leading to disruption of the skin barrier and immune cell dysfunction. The aim of the current study is to develop a bacteriophage-based product that specifically targets S. aureus. Methods: For the discovery of phage, environmental samples were screened on 118 S. aureus strains isolated from skin samples, followed by multiple enrichment steps. Natural phages were isolated, subjected to Next-generation Sequencing (NGS), and analyzed using proprietary bioinformatics tools for undesirable genes (toxins, antibiotic resistance genes, lysogeny potential), taxonomic classification, and purity. Phage host range was determined by an efficiency of plating (EOP) value above 0.1 and the ability of the cocktail to completely lyse liquid bacterial culture under different growth conditions (e.g., temperature, bacterial stage). Results: Sequencing analysis demonstrated that the 118 S. aureus clinical strains were distributed across the phylogenetic tree of all available Refseq S. aureus (~10,750 strains). Screening environmental samples on the S. aureus isolates resulted in the isolation of 50 lytic phages from different genera, including Silviavirus, Kayvirus, Podoviridae, and a novel unidentified phage. NGS sequencing confirmed the absence of toxic elements in the phages’ genomes. The host range of the individual phages, as measured by the efficiency of plating (EOP), ranged between 41% (48/118) to 79% (93/118). Host range studies in liquid culture revealed that a subset of the phages can infect a broad range of S. aureus strains in different metabolic states, including stationary state. Combining the single-phage EOP results of selected phages resulted in a broad host range cocktail which infected 92% (109/118) of the strains. When tested in vitro in a liquid infection assay, clearance was achieved in 87% (103/118) of the strains, with no evidence of phage resistance throughout the study (24 hours). A S. aureus host was identified that can be used for the production of all the phages in the cocktail at high titers suitable for large-scale manufacturing. This host was validated for the absence of contaminating prophages using advanced NGS methods combined with multiple production cycles. The phages are produced under optimized scale-up conditions and are being used for the development of a topical formulation (BX005) that may be administered to subjects with atopic dermatitis. Conclusions: A cocktail of natural phages targeting S. aureus was effective in reducing bacterial burden across multiple assays. Phage products may offer safe and effective steroid-sparing options for atopic dermatitis.

Keywords: atopic dermatitis, bacteriophage cocktail, host range, Staphylococcus aureus

Procedia PDF Downloads 131
395 Clinical Pathway for Postoperative Organ Transplantation

Authors: Tahsien Okasha

Abstract:

Transplantation medicine is one of the most challenging and complex areas of modern medicine. Some of the key areas for medical management are the problems of transplant rejection, during which the body has an immune response to the transplanted organ, possibly leading to transplant failure and the need to immediately remove the organ from the recipient. When possible, transplant rejection can be reduced through serotyping to determine the most appropriate donor-recipient match and through the use of immunosuppressant drugs. Postoperative care actually begins before the surgery in terms of education, discharge planning, nutrition, pulmonary rehabilitation, and patient/family education. This also allows for expectations to be managed. A multidisciplinary approach is the key, and collaborative team meetings are essential to ensuring that all team members are "on the same page." .The following clinical pathway map and guidelines with the aim to decrease alteration in clinical practice and are intended for those healthcare professionals who look after organ transplant patients. They are also intended to be useful to both medical and surgical trainees as well as nurse specialists and other associated healthcare professionals involved in the care of organ transplant patients. This pathway is general pathway include the general guidelines that can be applicable for all types of organ transplant with special considerations to each organ.

Keywords: postoperative care, organ transplant, clinical pathway, patient

Procedia PDF Downloads 427
394 The Discussion of Peritoneal Dialysis Patients Taking Proper Portion of Valacyclovir

Authors: Wan Shan Chiang, Charn Ting Wang, Wei-Chih Kan, Hui-Chen Huang

Abstract:

Dialysis patients have risk in Zoster virus because of low immune. Valacyclovir (product name: Valtex) 500mg/tab, an anti-zoster virus medicine, is digested in kidney and it has side-effect of nervous system in patients with malfunction kidneys. Although the clinical basis of the proposed administration, we found that patients still have side effects. So we want to explore the appropriate dose of peritoneal dialysis patients. We read small samples of case reports and analyze 8 cases in our hospital, some patients’ Kt/v, match the standard of dialysis, and still go to the toilet, they still have side effect seriously with 500mg portion. The solution to this includes stopping medicine, reduction of medicine, increase of liquid change and timely hemodialysis and all of them speed up the recovery. The safety of medication needs extra attention of medical care employee. If they can tell the doctor if the patient has urine or not in his or her Kt/v, the doctor can prescribe the medicine accordingly. About the limitation, due to the lack of cases and related pharmacokinetics numbers. Therefore, for peritoneal patients, we think 500mg/48hoursis the saves. We also want to remind pharmaceuticals to revise the portion taken by patients, so that the doctor may judge the use.

Keywords: herpes zoster, Valacyclovir, peritoneal dialysis, health education

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393 SLAMF5 Regulates Myeloid Cells Activation in the Eae Model

Authors: Laura Bellassen, Idit Shachar

Abstract:

Multiple sclerosis (MS) is a chronic neurological disorder characterized by demyelination of the central nervous system (CNS), leading to a wide range of physical and cognitive impairments. Myeloid cells in the CNS, such microglia and border associated macrophage cells, participate in the neuroinflammation in MS. Activation of those cells in MS contributes to the inflammatory response in the CNS and recruitment of immune cells in the this compartment. SLAMF5 is a cell surface receptor that functions as a homophilic adhesion molecule, whose signaling can activate or inhibit leukocyte function. In the current study we followed the expression and function of SLAMF5 in myeloid cells in the CNS and in the periphery in the murine model for MS, the experimental autoimmune encephalomyelitis model (EAE). Our results show that SLAMF5 deficiency or blocking decreases the expression of activation molecules and costimulatory molecules such as MHCII and CD80, resulting in delayed onset and reduced progression of the disease. Moreover, blocking SLAMF5 in peripheral monocytes derived from MS patients and iPSC-derived microglia cells, controls the expression of HLA-DR and CD80. Thus, SLAMF5 is a regulator of myeloid cells function and can serve as a therapeutic target in autoimmune disorders as Multiple Sclerosis.

Keywords: multiple sclerosis, EAE model, myeloid cells, new antibody, neuroimmunology

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392 Understanding the Fundamental Driver of Semiconductor Radiation Tolerance with Experiment and Theory

Authors: Julie V. Logan, Preston T. Webster, Kevin B. Woller, Christian P. Morath, Michael P. Short

Abstract:

Semiconductors, as the base of critical electronic systems, are exposed to damaging radiation while operating in space, nuclear reactors, and particle accelerator environments. What innate property allows some semiconductors to sustain little damage while others accumulate defects rapidly with dose is, at present, poorly understood. This limits the extent to which radiation tolerance can be implemented as a design criterion. To address this problem of determining the driver of semiconductor radiation tolerance, the first step is to generate a dataset of the relative radiation tolerance of a large range of semiconductors (exposed to the same radiation damage and characterized in the same way). To accomplish this, Rutherford backscatter channeling experiments are used to compare the displaced lattice atom buildup in InAs, InP, GaP, GaN, ZnO, MgO, and Si as a function of step-wise alpha particle dose. With this experimental information on radiation-induced incorporation of interstitial defects in hand, hybrid density functional theory electron densities (and their derived quantities) are calculated, and their gradient and Laplacian are evaluated to obtain key fundamental information about the interactions in each material. It is shown that simple, undifferentiated values (which are typically used to describe bond strength) are insufficient to predict radiation tolerance. Instead, the curvature of the electron density at bond critical points provides a measure of radiation tolerance consistent with the experimental results obtained. This curvature and associated forces surrounding bond critical points disfavors localization of displaced lattice atoms at these points, favoring their diffusion toward perfect lattice positions. With this criterion to predict radiation tolerance, simple density functional theory simulations can be conducted on potential new materials to gain insight into how they may operate in demanding high radiation environments.

Keywords: density functional theory, GaN, GaP, InAs, InP, MgO, radiation tolerance, rutherford backscatter channeling

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391 Effects of Propolis on Immunomodulatory and Antibody Production in Broilers

Authors: Yu-Hsiang Yu

Abstract:

The immunomodulatory effect of propolis has been widely investigated in the past decade. However, the beneficial effects in broilers are still poorly understood. The aim of this study was to evaluate the effect of propolis added in drinking water on immunomodulatory and antibody production in broiler. Total of 48 chicks were randomly allocated into four groups with 12 broilers per group. All birds were intranasal inoculated with Newcastle Disease vaccine at 4 and 14 days old of age. Four groups, including control without any treatment, groups of A, B and F [3 days of anterior (A), 3 days of posterior (P) and 6 days of full (F)] were supplied the propolis at 300 ppm in drinking water when vaccination was performed, respectively. Our results showed that no significant difference was found in growth performance, antibody production and immune organ index among groups. However, propolis treatments in broilers significantly reduced IL-4 expression in spleen at 14 days-old of age and bursa at 28 days-old of age compared with control group. The expression of IFN-gamma in spleen (A, P and F group) and bursal (F group) were elevated compared with control group at 28 days-old of age. In conclusion, our results indicated that propolis-treated birds could bear the capability for immunomodulatory effects by change Th1 subset cytokine expression in vaccination.

Keywords: propolis, broiler, immunomodulatory, vaccination

Procedia PDF Downloads 305
390 A Model of Human Security: A Comparison of Vulnerabilities and Timespace

Authors: Anders Troedsson

Abstract:

For us humans, risks are intimately linked to human vulnerabilities - where there is vulnerability, there is potentially insecurity, and risk. Reducing vulnerability through compensatory measures means increasing security and decreasing risk. The paper suggests that a meaningful way to approach the study of risks (including threats, assaults, crisis etc.), is to understand the vulnerabilities these external phenomena evoke in humans. As is argued, the basis of risk evaluation, as well as responses, is the more or less subjective perception by the individual person, or a group of persons, exposed to the external event or phenomena in question. This will be determined primarily by the vulnerability or vulnerabilities that the external factor are perceived to evoke. In this way, risk perception is primarily an inward dynamic, rather than an outward one. Therefore, a route towards an understanding of the perception of risks, is a closer scrutiny of the vulnerabilities which they can evoke, thereby approaching an understanding of what in the paper is called the essence of risk (including threat, assault etc.), or that which a certain perceived risk means to an individual or group of individuals. As a necessary basis for gauging the wide spectrum of potential risks and their meaning, the paper proposes a model of human vulnerabilities, drawing from i.a. a long tradition of needs theory. In order to account for the subjectivity factor, which mediates between the innate vulnerabilities on the one hand, and the event or phenomenon out there on the other hand, an ensuing ontological discussion about the timespace characteristics of risk/threat/assault as perceived by humans leads to the positing of two dimensions. These two dimensions are applied on the vulnerabilities, resulting in a modelling effort featuring four realms of vulnerabilities which are related to each other and together represent a dynamic whole. In approaching the problem of risk perception, the paper thus defines the relevant realms of vulnerabilities, depicting them as a dynamic whole. With reference to a substantial body of literature and a growing international policy trend since the 1990s, this model is put in the language of human security - a concept relevant not only for international security studies and policy, but also for other academic disciplines and spheres of human endeavor.

Keywords: human security, timespace, vulnerabilities, risk perception

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389 Effects of Oral Resveratrol Supplementation on Inflammation and Quality of Life in Patients with Ulcerative Colitis

Authors: M. Samsami, A. Hekmatdoost, N. Ebrahimi Daryani, P. Rezanejad Asl

Abstract:

Ulcerative colitis (UC) is an inflammatory bowel disease in which immune and inflammatory factors are thought to be effective in this disease. Resveratrol is an antioxidant and anti-inflammatory compound. This study determined the effects of resveratrol compound on inflammatory factors in patients with ulcerative colitis. This study was a double-blind randomized clinical trial conducted on 50 patients with UC. Subjects received one capsule daily for 6 wk of either resveratrol (500 mg) or a placebo. Inflammatory factors, anthropometric measures, and IBDQ-9 (Inflammatory Bowel Disease Questionnaire-9) scores were assessed at baseline and at the end of the study. STATA12 software was used for data analysis. No significant differences were found in the background variables between the two groups at baseline. The results indicated that resveratrol supplementation for 6 week significantly decreased plasma levels of TNF-a and hs-CRP and the activity of NF-κB over the placebo group (p<0.001). Significant differences remained after adjustment for vitamin C (p<0.0001). The IBDQ-9 scores increased significantly in the resveratrol group over the placebo group (p<0.001). The findings of this study showed that resveratrol supplementation can be useful in patients with ulcerative colitis.

Keywords: IBD, inflammation, resveratrol, ulcerative colitis

Procedia PDF Downloads 382
388 Electroactive Ferrocenyl Dendrimers as Transducers for Fabrication of Label-Free Electrochemical Immunosensor

Authors: Sudeshna Chandra, Christian Gäbler, Christian Schliebe, Heinrich Lang

Abstract:

Highly branched dendrimers provide structural homogeneity, controlled composition, comparable size to biomolecules, internal porosity and multiple functional groups for conjugating reactions. Electro-active dendrimers containing multiple redox units have generated great interest in their use as electrode modifiers for development of biosensors. The electron transfer between the redox-active dendrimers and the biomolecules play a key role in developing a biosensor. Ferrocenes have multiple and electrochemically equivalent redox units that can act as electron “pool” in a system. The ferrocenyl-terminated polyamidoamine dendrimer is capable of transferring multiple numbers of electrons under the same applied potential. Therefore, they can be used for dual purposes: one in building a film over the electrode for immunosensors and the other for immobilizing biomolecules for sensing. Electrochemical immunosensor, thus developed, exhibit fast and sensitive analysis, inexpensive and involve no prior sample pre-treatment. Electrochemical amperometric immunosensors are even more promising because they can achieve a very low detection limit with high sensitivity. Detection of the cancer biomarkers at an early stage can provide crucial information for foundational research of life science, clinical diagnosis and prevention of disease. Elevated concentration of biomarkers in body fluid is an early indication of some type of cancerous disease and among all the biomarkers, IgG is the most common and extensively used clinical cancer biomarkers. We present an IgG (=immunoglobulin) electrochemical immunosensor using a newly synthesized redox-active ferrocenyl dendrimer of generation 2 (G2Fc) as glassy carbon electrode material for immobilizing the antibody. The electrochemical performance of the modified electrodes was assessed in both aqueous and non-aqueous media using varying scan rates to elucidate the reaction mechanism. The potential shift was found to be higher in an aqueous electrolyte due to presence of more H-bond which reduced the electrostatic attraction within the amido groups of the dendrimers. The cyclic voltammetric studies of the G2Fc-modified GCE in 0.1 M PBS solution of pH 7.2 showed a pair of well-defined redox peaks. The peak current decreased significantly with the immobilization of the anti-goat IgG. After the immunosensor is blocked with BSA, a further decrease in the peak current was observed due to the attachment of the protein BSA to the immunosensor. A significant decrease in the current signal of the BSA/anti-IgG/G2Fc/GCE was observed upon immobilizing IgG which may be due to the formation of immune-conjugates that blocks the tunneling of mass and electron transfer. The current signal was found to be directly related to the amount of IgG captured on the electrode surface. With increase in the concentration of IgG, there is a formation of an increasing amount of immune-conjugates that decreased the peak current. The incubation time and concentration of the antibody was optimized for better analytical performance of the immunosensor. The developed amperometric immunosensor is sensitive to IgG concentration as low as 2 ng/mL. Tailoring of redox-active dendrimers provides enhanced electroactivity to the system and enlarges the sensor surface for binding the antibodies. It may be assumed that both electron transfer and diffusion contribute to the signal transformation between the dendrimers and the antibody.

Keywords: ferrocenyl dendrimers, electrochemical immunosensors, immunoglobulin, amperometry

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387 Prevention of Biocompounds and Amino Acid Losses in Vernonia amygdalina duringPost Harvest Treatment Using Hot Oil-Aqueous Mixture

Authors: Nneka Nkechi Uchegbu, Temitope Omolayo Fasuan

Abstract:

This study investigated how to reduce bio-compounds and amino acids in V. amygdalina leaf during processing as a functional food ingredient. Fresh V. amygdalina leaf was processed using thermal oil-aqueous mixtures (soybean oil: aqueous and palm oil: aqueous) at 1:40 and 130 (v/v), respectively. Results indicated that the hot soybean oil-aqueous mixture was the most effective in preserving the bio-compounds and amino acids with retention potentials of 80.95% of the bio-compounds at the rate of 90-100%. Hot palm oil-aqueous mixture retained 61.90% of the bio-compounds at the rate of 90-100% and hot aqueous retained 9.52% of the bio-compounds at the same rate. During the debittering process, seven new bio-compounds were formed in the leaves treated with hot soybean oil-aqueous mixture, six in palm oil-aqueous mixture, and only four in hot aqueous leaves. The bio-compounds in the treated leaves have potential functions as antitumor, antioxidants, antihistaminic, anti-ovarian cancer, anti-inflammatory, antiarthritic, hepatoprotective, antihistaminic, haemolytic 5-α reductase inhibitor, nt, immune-stimulant, diuretic, antiandrogenic, and anaemiagenic. Alkaloids and polyphenols were retained at the rate of 81.34-98.50% using oil: aqueous mixture while aqueous recorded the rate of 33.47-41.46%. Most of the essential amino acids were retained at a rate above 90% through the aid of oil. The process is scalable and could be employed for domestic and industrial applications.

Keywords: V. amygdalina leaf, bio-compounds, oil-aqueous mixture, amino acids

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386 The Pharmacology and Physiology of Steroid Oral Contraceptives

Authors: Ragy Raafat Gaber Attaalla

Abstract:

PIP: This review, based on 2 large-scale studies, discusses the pharmacology and physiology of oral steroid contraceptives (OCs). The pharmacological distinction between synthetic and naturally occurring steroids centers on changes in biological activity dependent on compound formulation and an individual's metabolism. OC mechanism of action is explained as the main prevention of ovulation by interference with gonadotropin-releasing hormone. Since some 52 metabolic alterations have been reported in OC users, these phenomena are dealt with in 3 categories: 1) effects on the primary target organs of the female reproductive tract (ovary, myometrium, endometrium, cervix, vagina, breasts, and hypothalamus), 2) general metabolic effects (serum proteins, carbohydrate metabolism, lipid metabolism, water and electrolyte metabolism, body weight, tryptophan metabolism, and vitamins and minerals), and 3) effects on other organ systems (liver, central nervous system, skin, genitourinary, gastrointestinal tract, eye, immune phenomena, and effect on subsequent fertility). The choice of the proper OC formulation and use of OCs by adolescents are discussed. Assessment of OC safety, contraindications, and patient monitoring are provided.

Keywords: steroid oral contraceptives, ovulation, female reproductive tract, metabolic effects

Procedia PDF Downloads 80
385 Fluorometric Aptasensor: Evaluation of Stability and Comparison to Standard Enzyme-Linked Immunosorbent Assay

Authors: J. Carlos Kuri, Varun Vij, Raymond J. Turner, Orly Yadid-Pecht

Abstract:

Celiac disease (CD) is an immune system disorder that is triggered by ingesting gluten. As a gluten-free (GF) diet has become a concern of many people for health reasons, a gold standard had to be nominated. Enzyme-linked immunosorbent assay (ELISA) has taken the seat of this role. However, multiple limitations were discovered, and with that, the desire for an alternative method now exists. Nucleic acid-based aptamers have become of great interest due to their selectivity, specificity, simplicity, and rapid-testing advantages. However, fluorescence-based aptasensors have been tagged as unstable, but lifespan details are rarely stated. In this work, the lifespan stability of a fluorescence-based aptasensor is shown over an 8-week-long study displaying the accuracy of the sensor and false negatives. This study follows 22 different samples, including GF and gluten-rich (GR) and soy sauce products, off-the-shelf products, and reference material from laboratories, giving a total of 836 tests. The analysis shows an accuracy of correctly classifying GF and GR products of 96.30% and 100%, respectively when the protocol is augmented with molecular sieves. The overall accuracy remains around 94% within the first four weeks and then decays to 63%.

Keywords: aptasensor, PEG, rGO, FAM, RM, ELISA

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384 The Overexpression of Horsegram MURLK Improves Regulation of Cell Death and Defense Responses to Microbial Pathogens

Authors: Shikha Masand, Sudesh Kumar Yadav

Abstract:

Certain protein kinases have been shown to be crucial for plant cell signaling pathways associated with plant immune responses. Here we identified a horsegram [Macrotyloma uniflorum (Lam.) Verdc.] malectin-like leucine rich receptor-like protein kinase (RLK) gene MuRLK. The functional MuRLK protein preferentially binds to mannose and N-acetyl glucosamine residues. MuRLK exists in the cytoplasm and also localizes to the plasma membrane of plant cells via its N-terminus. Over-expression of MuRLK in Arabidopsis enhances the basal resistance to infection with Pseudomonas syringae pv. tomato, Alternaria brassicicola and Hyaloperonospora arabidopsidis, are associated with elevated ROS bursts, MAPK activation, thus ultimately leading to hypersensitive cell death. Moreover, salicylic acid-dependent and jasmonic acid-dependent defense responses are also enhanced in the MuRLK-overexpressed plants that lead to HR-induced cell death. Together, these results suggest that MuRLK plays a key role in the regulation of plant cell death, early and late defense responses after the recognition of microbial pathogens.

Keywords: horsegram, Pseudomonas syringae pv. tomato, MuRLK, ROS burst, cell death, plant defense

Procedia PDF Downloads 229
383 Non-Mammalian Pattern Recognition Receptor from Rock Bream (Oplegnathus fasciatus): Genomic Characterization and Transcriptional Profile upon Bacterial and Viral Inductions

Authors: Thanthrige Thiunuwan Priyathilaka, Don Anushka Sandaruwan Elvitigala, Bong-Soo Lim, Hyung-Bok Jeong, Jehee Lee

Abstract:

Toll like receptors (TLRs) are a phylogeneticaly conserved family of pattern recognition receptors, which participates in the host immune responses against various pathogens and pathogen derived mitogen. TLR21, a non-mammalian type, is almost restricted to the fish species even though those can be identified rarely in avians and amphibians. Herein, this study was carried out to identify and characterize TLR21 from rock bream (Oplegnathus fasciatus) designated as RbTLR21, at transcriptional and genomic level. In this study, the full length cDNA and genomic sequence of RbTLR21 was identified using previously constructed cDNA sequence database and BAC library, respectively. Identified RbTLR21 sequence was characterized using several bioinformatics tools. The quantitative real time PCR (qPCR) experiment was conducted to determine tissue specific expressional distribution of RbTLR21. Further, transcriptional modulation of RbTLR21 upon the stimulation with Streptococcus iniae (S. iniae), rock bream iridovirus (RBIV) and Edwardsiella tarda (E. tarda) was analyzed in spleen tissues. The complete coding sequence of RbTLR21 was 2919 bp in length which can encode a protein consisting of 973 amino acid residues with molecular mass of 112 kDa and theoretical isoelectric point of 8.6. The anticipated protein sequence resembled a typical TLR domain architecture including C-terminal ectodomain with 16 leucine rich repeats, a transmembrane domain, cytoplasmic TIR domain and signal peptide with 23 amino acid residues. Moreover, protein folding pattern prediction of RbTLR21 exhibited well-structured and folded ectodomain, transmembrane domain and cytoplasmc TIR domain. According to the pair wise sequence analysis data, RbTLR21 showed closest homology with orange-spotted grouper (Epinephelus coioides) TLR21with 76.9% amino acid identity. Furthermore, our phylogenetic analysis revealed that RbTLR21 shows a close evolutionary relationship with its ortholog from Danio rerio. Genomic structure of RbTLR21 consisted of single exon similar to its ortholog of zebra fish. Sevaral putative transcription factor binding sites were also identified in 5ʹ flanking region of RbTLR21. The RBTLR 21 was ubiquitously expressed in all the tissues we tested. Relatively, high expression levels were found in spleen, liver and blood tissues. Upon induction with rock bream iridovirus, RbTLR21 expression was upregulated at the early phase of post induction period even though RbTLR21 expression level was fluctuated at the latter phase of post induction period. Post Edwardsiella tarda injection, RbTLR transcripts were upregulated throughout the experiment. Similarly, Streptococcus iniae induction exhibited significant upregulations of RbTLR21 mRNA expression in the spleen tissues. Collectively, our findings suggest that RbTLR21 is indeed a homolog of TLR21 family members and RbTLR21 may be involved in host immune responses against bacterial and DNA viral infections.

Keywords: rock bream, toll like receptor 21 (TLR21), pattern recognition receptor, genomic characterization

Procedia PDF Downloads 522
382 A CD40 Variant is Associated with Systemic Bone Loss Among Patients with Rheumatoid Arthritis

Authors: Rim Sghiri, Samia Al Shouli, Hana Benhassine, Nejla Elamri, Zahid Shakoor, Foued Slama, Adel Almogren, Hala Zeglaoui, Elyes Bouajina, Ramzi Zemni

Abstract:

Objectives: Little is known about genes predisposing to systemic bone loss (SBL) in rheumatoid arthritis (RA). Therefore, we examined the association between SBL and a variant of CD40 gene, which is known to play a critical role in both immune response and bone homeostasis among patients with RA. Methods: CD40 rs48104850 was genotyped in 176 adult RA patients. Bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry (DXA). Results: Low BMD was observed in 116 (65.9%) patients. Among them, 60 (34.1%) had low femoral neck (FN) Z score, 72 (40.9%) had low total femur (TF) Z score, and 105 (59.6%) had low lumbar spine (LS) Z score. CD40 rs4810485 was found to be associated with reduced TF Z score with the CD40 rs4810485 T allele protecting against reduced TF Z score (OR = 0.40, 95% CI = 0.23-0.68, p = 0.0005). This association was confirmed in the multivariate logistic regression analysis (OR=0.31, 95% CI= 0.16-0.59, p=3.84 x 10₋₄). Moreover, median FN BMD was reduced among RA patients with CD40 rs4810485 GG genotype compared to RA patients harbouring CD40 rs4810485 TT and GT genotypes (0.788± 0.136 versus 0.826± 0.146g/cm², p=0.001). Conclusion: This study, for the first time ever, demonstrated an association between a CD40 genetic variant and SBL among patients with RA.

Keywords: rheumatoid arthritis, CD40 gene, bone mineral density, systemic bone loss, rs48104850

Procedia PDF Downloads 432
381 Proteomic Analysis of Excretory Secretory Antigen (ESA) from Entamoeba histolytica HM1: IMSS

Authors: N. Othman, J. Ujang, M. N. Ismail, R. Noordin, B. H. Lim

Abstract:

Amoebiasis is caused by the Entamoeba histolytica and still endemic in many parts of the tropical region, worldwide. Currently, there is no available vaccine against amoebiasis. Hence, there is an urgent need to develop a vaccine. The excretory secretory antigen (ESA) of E. histolytica is a suitable biomarker for the vaccine candidate since it can modulate the host immune response. Hence, the objective of this study is to identify the proteome of the ESA towards finding suitable biomarker for the vaccine candidate. The non-gel based and gel-based proteomics analyses were performed to identify proteins. Two kinds of mass spectrometry with different ionization systems were utilized i.e. LC-MS/MS (ESI) and MALDI-TOF/TOF. Then, the functional proteins classification analysis was performed using PANTHER software. Combination of the LC -MS/MS for the non-gel based and MALDI-TOF/TOF for the gel-based approaches identified a total of 273 proteins from the ESA. Both systems identified 29 similar proteins whereby 239 and 5 more proteins were identified by LC-MS/MS and MALDI-TOF/TOF, respectively. Functional classification analysis showed the majority of proteins involved in the metabolic process (24%), primary metabolic process (19%) and protein metabolic process (10%). Thus, this study has revealed the proteome the E. histolytica ESA and the identified proteins merit further investigations as a vaccine candidate.

Keywords: E. histolytica, ESA, proteomics, biomarker

Procedia PDF Downloads 318
380 Epigenetic Mechanisms Involved in the Occurrence and Development of Infectious Diseases

Authors: Frank Boris Feutmba Keutchou, Saurelle Fabienne Bieghan Same, Verelle Elsa Fogang Pokam, Charles Ursula Metapi Meikeu, Angel Marilyne Messop Nzomo, Ousman Tamgue

Abstract:

Infectious diseases are one of the most important causes of morbidity and mortality worldwide. These diseases are caused by micro-pathogenic organisms, such as bacteria, viruses, parasites, and fungi. Heritable changes in gene expression that do not involve changes to the underlying DNA sequence are referred to as epigenetics. Emerging evidence suggests that epigenetic mechanisms are important in the emergence and progression of infectious diseases. Pathogens can manipulate host epigenetic machinery to promote their own replication and evade immune responses. The Human Genome Project has provided new opportunities for developing better tools for the diagnosis and identification of target genes. Several epigenetic modifications, such as DNA methylation, histone modifications, and non-coding RNA expression, have been shown to influence infectious disease outcomes. Understanding the epigenetic mechanisms underlying infectious diseases may result in the progression of new therapeutic approaches focusing on host-pathogen interactions. The goal of this study is to show how different infectious agents interact with host cells after infection.

Keywords: epigenetic, infectious disease, micro-pathogenic organism, phenotype

Procedia PDF Downloads 58
379 The Desire for Significance & Memorability in Popular Culture: A Cognitive Psychological Study of Contemporary Literature, Art, and Media

Authors: Israel B. Bitton

Abstract:

“Memory” is associated with various phenomena, from physical to mental, personal to collective and historical to cultural. As part of a broader exploration of memory studies in philosophy and science (slated for academic publication October 2021), this specific study employs analytical methods of cognitive psychology and philosophy of memory to theorize that A) the primary human will (drive) is to significance, in that every human action and expression can be rooted in a most primal desire to be cosmically significant (however that is individually perceived); and B) that the will to significance manifests as the will to memorability, an innate desire to be remembered by others after death. In support of these broad claims, a review of various popular culture “touchpoints”—historic and contemporary records spanning literature, film and television, traditional news media, and social media—is presented to demonstrate how this very theory is repeatedly and commonly expressed (and has been for a long time) by many popular public figures as well as “everyday people.” Though developed before COVID, the crisis only increased the theory’s relevance: so many people were forced to die alone, leaving them and their loved ones to face even greater existential angst than what ordinarily accompanies death since the usual expectations for one’s “final moments” were shattered. To underscore this issue of, and response to, what can be considered a sociocultural “memory gap,” this study concludes with a summary of several projects launched by journalists at the height of the pandemic to document the memorable human stories behind COVID’s tragic warped speed death toll that, when analyzed through the lens of Viktor E. Frankl’s psychoanalytical perspective on “existential meaning,” shows how countless individuals were robbed of the last wills and testaments to their self-significance and memorability typically afforded to the dying and the aggrieved. The resulting insight ought to inform how government and public health officials determine what is truly “non-essential” to human health, physical and mental, at times of crisis.

Keywords: cognitive psychology, covid, neuroscience, philosophy of memory

Procedia PDF Downloads 159
378 Carotenoids a Biologically Important Bioactive Compound

Authors: Aarti Singh, Anees Ahmad

Abstract:

Carotenoids comprise a group of isoprenoid pigments. Carotenes, xanthophylls and their derivatives have been found to play an important role in all living beings through foods, neutraceuticals and pharmaceuticals. α-carotene, β-carotene and β-cryptoxanthin play a vital role in humans to provide vitamin A source for the growth, development and proper functioning of immune system and vision. They are very crucial for plants and humans as they protect from photooxidative damage and are excellent antioxidants quenching singlet molecular oxygen and peroxyl radicals. Diet including more intake of carotenoids results in reduced threat of various chronic diseases such as cancer (lung, breast, prostrate, colorectal and ovarian cancers) and coronary heart diseases. The blue light filtering efficiency of the carotenoids in liposomes have been reported to be maximum in lutein followed by zeaxanthin, β-carotene and lycopene. Lycopene plays a vital role for the protection from CVD. Lycopene in serum is directly related to reduced risk of osteoporosis in postmenopausal women. Carotenoids have major role in the treatment of skin disorders. There is need to identify and isolate novel carotenoids from diverse natural sources for human health benefits.

Keywords: antioxidants, carotenoids, neutraceuticals, osteoporosis, pharmaceuticals

Procedia PDF Downloads 360
377 Assessing Immunization across Life Stages of the Cuban Treefrog (Osteopilus septentrionalis) to the Pathogenic Chytrid Fungus (Batrachochytrium dendrobatidis)

Authors: Kerri L. Surbaugh, Lakmini Y. Mallikarachchi, Jason R. Rohr

Abstract:

Emerging diseases are key factors in the disconcerting rate of contemporary amphibian declines. The chytrid fungus, Batrachochytrium dendrobatidis (Bd), ranks among the chief pathogenic challenges to vulnerable amphibian populations. Although live Bd can immunosuppress amphibian hosts, amphibian exposure to dead Bd can induce an adaptive immune response, leading to acquired resistance to the pathogen. In this experiment, dose and duration of flash-frozen Bd were manipulated over a variety of life-stages of the Cuban treefrog (Osteopilus septentrionalis) and the magnitude of acquired resistance to the pathogen was quantified via qPCR analyses of spore abundance post subsequent live Bd challenges. It was found that Cuban treefrogs can develop resistance to Bd and that life stage, dose and duration thresholds exist for acquired resistance. This experiment will aid in facilitating the development of a vaccine against Bd which could be used on location and could help curb worldwide amphibian declines associated with this pathogen.

Keywords: acquired resistance, ecoimmunology, emerging infectious disease, fungal host response, fungal pathogen, immunization

Procedia PDF Downloads 110
376 Vitamin D Deficiency is Associated with Increases IgE Receptors in Children with Asthma

Authors: A. Vijayendra Chary, R. Hemalatha

Abstract:

Background: Vitamin D is a potent modulator of the immune system and is involved in regulating cell proliferation and differentiation. Vitamin D deficiency has been linked to increased severity of asthma in children. Asthma has dramatically increased in past decades, particular in developing countries and affects up to 20% of the population. IgE and its receptors, CD23 (FcεRII) and CD 21, play an essential role in all allergic conditions. Methods: A case control study was conducted on asthma and age and sex matched control children. 25 hydroxyvitamin D3 was quantified by HPLC; CD23; and CD21 expression on B cells were performed by flow cytometry. Total Histamine, total IGE and IL-5 and IFN-γ cytokines were determined by ELISA in blood samples of bronchial asthma (n=45) and control children (n=45). Results: The mean ± SE of vitamin D was significantly (p<0.05) low in asthma children (13.6±0.54 ng/mL) than in controls (17.4 ± 0.37 ng/mL). The mean (%) ± SE of CD23 and CD21 expression on B cells were significantly (p<0.01) high in asthma (1.02±0.09; 1.67± 0.13), when compared to controls (0.24±0.01; 0.94±0.03) respectively. The mean± SE of Serum IgE and blood histamine levels in asthma children (354.52 ± 17.33 IU/mL; 53.27 ± 2.54 nM/mL) were increased (P<0.05) when compared to controls (183.12±17.62 IU/mL 39.34±4.16 nM/mL) respectively and IFN-γ (Th1 cytokine) was lower (P<0.01) (16.37±1.27 pg/mL) than in controls (43.34±6.21 pg/mL). Conclusion: Our study provides evidence that low vitamin D levels are associated with increased IgE receptors CD23 and CD21 on B cells. In addition, there was preferential activation of Th2 (IL-5) and suppression of Th1 (IFN-γ) cytokines in children with asthma.

Keywords: bronchial asthma, CD23, IgE, vitamin D

Procedia PDF Downloads 454
375 Coping Heat Stress By Crushed Fennel (Foeniculum Vulgare) Seeds in Broilers: Growth, Redox Balance, and Humoral Immune Response

Authors: Adia Fatima, Naila Chand, Rifat Ullah Khan

Abstract:

The goal of this study was to determine how fennel seed supplementation affected broiler growth, carcass quality, antioxidant status, and antibody titer in heat-stressed broilers. A total of 720 one-day-old broiler chickens were weighed and assigned to 28-floor pens (25 broiler chickens per pen). The broiler chickens were housed in a thermoneutral (TN) environment and were exposed to heat stress (HS). For 23 hours, the broiler chickens were kept under fluorescent lighting. For 35d, HS broiler chickens were fed a control diet and three levels of fennel seeds powder at rates of 15g/kg (Fen-15), 20 g/kg (Fen-20), and 25 g/kg (Fen-25). Overall feed intake, weight gain, and dressing % were considerably greater (P < 0.05) in Fen-25 and TN, but FCR was significantly reduced (P<0.01) in the same groups. When TN, Fen-20, and Fen-25 were compared to the control, malondialdehyde (MDA), paraoxonase (PON1), and antibody titer against New Castle disease (ND) were considerably (P < 0.05) greater. Further, the linear and quadratic response was for feed intake, weight gain, FCR, MDA, PON1, and ND titer. It was concluded that Fen-20 and Fen-25 increased broiler growth, carcass quality, antioxidant status, and immunological response under HS conditions.

Keywords: heat stress, growth, antioxidant, immunity

Procedia PDF Downloads 75
374 A Review: Carotenoids a Biologically Important Bioactive Compound

Authors: Aarti Singh, Anees Ahmad

Abstract:

Carotenoids comprise a group of isoprenoid pigments. Carotenes, xanthophylls and their derivatives have been found to play an important role in all living beings through foods, neutraceuticals and pharmaceuticals. α-carotene, β-carotene and β-cryptoxanthin play a vital role in humans to provide vitamin A source for the growth, development and proper functioning of immune system and vision. They are very crucial for plants and humans as they protect from photooxidative damage and are excellent antioxidants quenching singlet molecular oxygen and peroxyl radicals. Diet including more intake of carotenoids results in reduced threat of various chronic diseases such as cancer (lung, breast, prostate, colorectal and ovarian cancers) and coronary heart diseases. The blue light filtering efficiency of the carotenoids in liposomes have been reported to be maximum in lutein followed by zeaxanthin, β-carotene and lycopene. Lycopene play a vital role for the protection from CVD. Lycopene in serum is directly related to reduced risk of osteoporosis in postmenopausal women. Carotenoids have the major role in the treatment of skin disorders. There is a need to identify and isolate novel carotenoids from diverse natural sources for human health benefits.

Keywords: antioxidants, carotenoids, neutraceuticals, osteoporosis, pharmaceuticals

Procedia PDF Downloads 342
373 Effect of Chromium Yeast on Hematological Parameters in Camel Calves (Camelus dromedaries) Reared under Hot Summer Conditions

Authors: Khalid Ahmed Abdoun, Mohamed Abdulwahid Alsoufi, Ibrahim Abdullah Alhidary

Abstract:

The intention of this study was to evaluate the effect of dietary Cr supplementation on haematological parameters in camel calves reared under hot summer conditions. Fifteen male camel calves (5 – 6 months old) were randomly allotted to three dietary treatments (n = 5) for a period of 84 days. Camel calves were fed ad libitum on basal diet without Cr supplementation (control), basal diet supplemented with 0.5 mg Cr/kg DM (Cr 0.5) or basal diet supplemented with 1.0 mg Cr/kg DM (Cr 1.0). During this, blood samples were collected every four weeks for hematological examination. The obtained results revealed that dietary Cr supplementation to camel calves reared under hot summer did not show significant effects (P> 0.05) on hematological variables. However, the neutrophil to lymphocytes ratio (N: L ratio) was significantly (P < 0.05) reduced in camel calves fed on diets supplemented with chromium. In conclusion, Chromium supplementation to the diet of camel calves did not show any significant effects on hematological variables. Whereas, the neutrophil to lymphocytes ratio (N: L ratio) was reduced in camel calves fed diets supplemented with chromium.

Keywords: camel calves, chromium, haematological, immune response

Procedia PDF Downloads 256
372 Inhibition of Variant Surface Glycoproteins Translation to Define the Essential Features of the Variant Surface Glycoprotein in Trypanosoma brucei

Authors: Isobel Hambleton, Mark Carrington

Abstract:

Trypanosoma brucei, the causal agent of a range of diseases in humans and livestock, evades the mammalian immune system through a population survival strategy based on the expression of a series of antigenically distinct variant surface glycoproteins (VSGs). RNAi mediated knockdown of the active VSG gene triggers a precytokinesis cell cycle arrest. To determine whether this phenotype is the result of reduced VSG transcript or depleted VSG protein, we used morpholino antisense oligonucleotides to block translation of VSG mRNA. The same precytokinesis cell cycle arrest was observed, suggesting that VSG protein abundance is monitored closely throughout the cell cycle. An inducible expression system has been developed to test various GPI-anchored proteins for their ability to rescue this cell cycle arrest. This system has been used to demonstrate that wild-type VSG expressed from a T7 promoter rescues this phenotype. This indicates that VSG expression from one of the specialised bloodstream expression sites (BES) is not essential for cell division. The same approach has been used to define the minimum essential features of a VSG necessary for function.

Keywords: bloodstream expression site, morpholino, precytokinesis cell cycle arrest, variant surface glycoprotein

Procedia PDF Downloads 123