|
|
HLA neshody u pacientů po opakované transplantaci ledviny a incidence akutní buněčné a protilátkami zprostředkované rejekce.
Karasová, Alexandra ; Slavčev, Antonij (advisor) ; Ambrůzová, Zuzana (referee)
Kidney transplantation is the most appropriate treatment for end-stage kidney failure. The risk of graft failure in retransplanted patients is generally higher than in first-transplant patients due to immunological and non-immunological reasons. An important risk factor to consider for retransplant patients is their sensitization, i.e. the presence of antibodies directed to HLA antigens of previous donor(s). For that reason, a project called Forbidden (Non-acceptable) Antigens was launched by IKEM with the aim of reducing the incidence of acute cellular and antibody-mediated rejection in retransplant patients. Work on the project was carried out between the years 2011-2013. Forbidden antigens were defined as mismatched HLA antigens of previous kidney donor(s) against which patients waiting for retransplantation produced antibodies. The aim of this diploma thesis is to evaluate whether the incidence of rejection is lower in patients with forbidden HLA antigens in comparison with a control cohort, where no forbidden antigens are defined. 234 patients (162 males and 72 females) were included in the study. Almost all tested patients were producing HLA antibodies (90.2%) and forbidden antigens were determined in 71.4% of patients. In a control group of 267 patients waiting for their first transplantation, the...
|
|
|
Cytokine polarisation in immunopathological disorders
Durilová, Marianna ; Štechová, Kateřina (advisor) ; Tučková, Ludmila (referee) ; Slavčev, Antonij (referee)
6 Abstract Cytokines as primary modulators of immune system cells play a key role in their development, maintenance and activity of each cell population. Cytokine profile of peripheral blood mononuclear cells thus reflects the immunopathological events involved in pathogenesis of the disease. Focus of my thesis was cytokine dysbalance in several immunopathological disorders (type 1 diabetes mellitus, autoimmune thyroiditis, allergic colitis) with the aim to find distinctive cytokine profile of each disorder and to point out common features and differences in these disorders. Protein array and enzyme-linked immunosorbent assay (ELISA) method were used for analysis of cytokines in breast milk and cytokines produced in vitro by peripheral and cord blood mononuclear cells spontaneously and after stimulation by autoantigens. First immunological disorder to study was type 1 diabetes mellitus (T1D), where patients with T1D were studied (n = 10) as well as their first degree relatives (n = 9), with particular group of neonates whose one parent suffered from T1D (n = 52). In patients with T1D prediabetic phase was dominated by spontaneous and postimulatory production of Th1- associated cytokines (IFN-γ, TNF-β) which dropped at the time of T1D manifestation and remained suppressed for at least two following years....
|
|
|
ELISpot methodology and prediction of acute rejection after renal transplantation.
Rybáková, Kateřina ; Slavčev, Antonij (advisor) ; Mrázek, František (referee)
Transplantation is the best therapeutic solution for patients with chronic renal failure. Due to the great advances in immunosuppressive therapy in the last decades, graft and patient survival have improved significantly. On the other hand, immunosuppressive therapy has serious side effects - too strong immunosuppression may lead to infection or malignancies, conversely insufficient immunosuppression may lead to graft rejection. Due to the grave consequences of acute rejection, the main goal of cooperation of clinicians and transplant immunologists is to stratify patients into groups with low, moderate and high risk of rejection based on the evaluation of various immunologic risk factors. There are reports in the literature that the numbers (frequencies) of interferon gamma (IFNγ) producing cells before transplantation may be helpful to identify patients with high risk of acute cellular rejection and to predict long-term survival of the graft. In this retrospective study we determined the pre-transplant frequencies of activated donor specific T lymphocytes producing IFNγ after short stimulation (24 hrs) by ELISpot (Enzyme-linked immunosorbent spot assay). The results were correlated with the incidence of acute cellular (ACR) and antibody-mediated (AMR) rejection and with other risk factors. In our...
|
|
|
Genetic and molecular factors influencing the outcome of solid organ transplantation
Pavlova, Yelena ; Slavčev, Antonij (advisor) ; Kalina, Tomáš (referee) ; Mrázek, František (referee)
Since its beginning, graft rejection remains the key problem of solid organ transplantation. This reaction of the recipient's immune system against mismatched antigens of the transplanted organ causes graft damage and consequently loss of its function. Rejection involves cellular (lymphocyte mediated) and humoral (antibody mediated) mechanisms. Among the genetic factors which may have a prognostic value in rejection risk evaluation are the Human Leukocyte Antigens (HLA) genotype, the Killer Immunoglobuline-like Receptor (KIR) gene repertoir, cytokine and other gene polymorphisms. These factors could be screened for before transplantation to find the best possible combination of genetic characteristics of the donor and recipient and to reveal patients with "risky" genotypes, who may need more intensive immunosuppression and more careful post-transplant follow-up. Molecular factors, such as HLA and non-HLA antibodies, soluble CD30 molecule (sCD30), Hepatocyte Growth Factor (HGF) and other cytokines, measured before and/or after transplantation in the recipient's blood may be helpful for rejection risk estimation and may also be used as post-transplant rejection onset markers. In our study, we focused on some of the above mentioned factors. We found that ethnicity plays a significant role in the...
|
|
|
Ethical aspects of stem cell donation
Březinová, Ludmila ; Štegmannová, Ingrid (advisor) ; Slavčev, Antonij (referee)
Donation of blood stem cells could help save the life of patients with a variety of hematological diseases. Despite its topicality it does not belong to widely known areas and a large section of the population deals with this issue only if it begins to relate to them personally. Therefore I would like to contribute with my work I would to the wider debate on this topic focusing on ethical issues. In the theoretical part I describe the history of the donation and transplantation of hematopoietic stem cells, which together are inseparable. I introduce the role of the Czech Stem Cells Donor Registry and the legislative definition of its functioning. For a comprehensive look at this issue I describe the methods of blood stem cells collection and their transplantation primarily to depict the practical issues and questions donors and patients are exposed to. The main part of my work is devoted to the ethically problematic areas which we as the registry staff can meet and whose solution we are exposed to. The research part of my work is focused on the donor perception of the need to be informed and devoted to the fate and identity of the stem cells recipient in the context of the entire donation process. The objective is to find the right approach to donors who selflessly undergo the process of donation....
|
|
|
Humoral rejection after kidney transplantation and monitoring antibodies against HLA and non-HLA antigens.
Valhová, Šárka ; Slavčev, Antonij (advisor) ; Mrázek, František (referee)
Kidney transplantation is the treatment of choice for patients with end stage renal failure and is associated with prolonged survival of patients and better quality of life than long-term dialysis. Simultaneously, however, transplantation carries the risk of immunological complications leading to graft rejection. A serious problem in patients after organ transplantation is the development of humoral rejection, which is most often associated with the presence of antibodies specific to HLA antigens, particularly against mismatched HLA antigens of the organ donor. In certain cases antibodies may be specific to antigens expressed on endothelial cells, not on lymphocytes, like MICA, MICB, ICAM, and up till now unidentified tissue-specific antigens. Humoral rejection has significantly worse prognosis for the transplanted kidney than cellular rejection, and therefore its timely diagnosis is of great importance for the subsequent choice of appropriate therapy. The diagnosis of humoral rejection is based on the simultaneous detection of C4d deposits in the peritubular capillaries of the transplanted kidney and the finding of antibodies specific to the mismatched antigens of the donor (donor specific antibodies, DSA). The aim of our retrospective study was to contribute to improvement of the diagnosis of acute and...
|
|
|
Molecular biology methods and their use for HLA antigen polymorphism determination
Brožová, Jitka ; Slavčev, Antonij (advisor) ; Trošan, Peter (referee)
HLA (Human Leukocyte Antigen) is a gene segment localized on the short arm of chromosome 6. This segment consists of three regions, I. and II. region encode HLA class I and HLA class II genes, in the III. region there are the complement genes, TNFα and other genes that are not evolutionary and functionally associated with HLA genes. HLA class I and class II genes encode cell-surface glycoproteins which in their binding sites present peptides to cells of the immune system. HLA genes are associated with many autoimmune and infectious diseases, although mostly the mechanisms of these associations remain unclear. HLA function as strong transplantation antigens, thus they represent a major obstacle in allogeneic organ transplantation and transplantation of hematopoietic cells. To prevent rejection of the transplanted organ, a match between the recipient and donor in the HLA antigens is necessary. Determination of donor and recipient matching is performed by HLA typing techniques. Nowadays for HLA typing in most laboratories in Europe and the USA are used methods of molecular biology. Among these methods, three main techniques based on the polymerase chain reaction (PCR) are applied, these are PCR-sequence-specific primers, PCR-sequence-specific oligonucleotide probes and PCR-sequencing-based typing....
|
|
|
HLA complex and association with autoimmune diseases
Karasová, Alexandra ; Slavčev, Antonij (advisor) ; Šírová, Milada (referee)
Autoimmune diseases are serious and sometimes life-threatening disorders that affect approximately 5 % of the world population and therefore represent a major socio-medical problem. The HLA complex is the best studied part of the human genome that encodes the HLA antigens, whose function is to present peptides to immune system (T-lymphocytes). During the study of the HLA complex it has been found that certain HLA antigens are strongly associated with the occurence of autoimmune diseases, despite the great progress in clarifying disease etiopathogenesis the mechanism of these associations is, however, not fully explained. Sometimes the association of autoimmune disease with the HLA complex is very strong, such as in ankylosing spondylitis or celiac disease, while in other diseases the association is relatively weak, suggesting a role of other genetic and / or environmental factors. The aim of this work is to briefly explain the structure and function of the HLA complex and its association with some severe autoimmune diseases.
|
|
|
Immunopathological and immunogenetic aspects of haematopietic stem cell and solid organ transplantations
Jindra, Pavel ; Boudová, Ludmila (advisor) ; Fakan, František (referee) ; Slavčev, Antonij (referee)
The genetic diversity of KIR genes and genotypes resembles of the HLA. Although the genes encoding KIR and HLA are located in different chromosomes and segregate independently, there is some evidence of some kind of co-evolution. Therefore, one could expect reduced KIR diversity within the HLA restricted population. A total of 41 unrelated individuals homozygous for ancestral HLA haplotype AH8.1 (HLA-A*0101-Cw*0701-B*0801- DRB1*0301-DQB1*0201), were typed for KIR genes. Over all, fourteen different genotypes were identified. The observed frequencies of KIR genes and genotypes composition generally mirror the published frequencies in Caucasians. Non-framework genes with frequency of more than 90 % included KIR2DL1, KIR2DL3, KIR3DL1, KIR2DS4 and KIR2DP1. Except for the KIR2DS4, all activating genes presented frequencies bellow 50 %. KIR2DS5 was the least frequent among activating genes (17 %), whereas KIR2DL5 (37 %) among inhibitory ones. The most frequent (39 %) was AA genotype. 22 individuals (54 %) had a copy of KIR haplotype A and B (AB genotype), whereas 3 (7%) were homozygous for B (BB genotype). Nine of 14 reported genotypes occurred only in one individual. Comparing with published and recorded genotypes (www.allelefrequencies.net), 5 genotypes were reported in less than 20 individuals worldwide and...
|
|
|
Laboratory Diagnostics and HLA Typization of Patients with Rheumatoid Artritis.
Škoda, Marek ; Půtová, Ivana (advisor) ; Slavčev, Antonij (referee)
This work studies the relationship between DRB1 alleles and production of clinically most important autoantibodies in patients with rheumatoid arthritis (RA). A group of 81 patients with RA were diagnosed in immunological laboratory and genotyped. The prevalence of most often tested analytes were determined: antinuclear antibodies (ANA), rheumatoid factor (RF), anti-CCP antibodies and anti-MCV antibodies. HLA-DRB1 alleles were detected using PCR-SSP low resolution. The aim of this study was to determine the frequency of DRB1 alleles in Czech patients and to investigate the relationship between DRB1 alleles and production of particular antibodies. The frequency of HLA-DRB1*01 and HLA-DRB1*04 alleles was significantly increased in RA patients compared to healthy subjects. In contrast, the frequency of DRB1*15 allele was significantly reduced. Studying the relationship between DRB1 alleles and presence of antibodies showed a significantly increased frequency of DRB1*04 allele in patients with positive ACPA antibodies (anti-CCP, anti-MCV). Regarding other antibodies (ANA, RF), no relationship between their production and presence of DRB1 alleles was found. Comparison of anti-CCP and anti-MCV antibodies levels between groups of RA patients with the presence and absence of DRB1*04 alleles showed no difference....
|
guest ::
