Search results for "Histocompatibility"
showing 10 items of 473 documents
Detection of Anti-MICA Antibodies in Patients Awaiting Kidney Transplantation, during the Post-transplant Course, and in Eluates from Rejected Kidney…
2005
Previously we have reported on the development of antibodies against MICA alleles in kidney transplant recipients. These alloantibodies have now been determined using a new assay using Luminex beads bound to soluble recombinant MICA antigens produced in insect cells. In the present study we have analyzed sera from 85 kidney transplant recipients on the waiting list and 66 patients transplanted within the last 4 years and 59 acid eluates obtained from allograft nephrectomy specimens. Many of the patients in those groups were sensitized and some had previous transplants (waiting list: 15%; post-tx: 7.6%; eluates 22%) and their sera were found to contain anti-human leukocyte antigen (HLA) and …
Hepatitis B surface antigen presentation and HLA-DRB1*– lessons from twins and peptide binding studies
2005
Summary The aim of this study was to investigate the underlying mechanisms of the genetic association between certain HLA-DRB1* alleles and the immune response to HBsAg vaccination. Therefore, HBsAg peptide binding to HLA-DR molecules was measured in vitro by peptide binding ELISAs. Additionally, HBsAg-specific T cell reaction and cytokine profile of immune response were analysed ex vivo in ELISPOT assays and DR-restriction of T-cell proliferative responses was investigated with HBsAg specific T cell clones. In addition, we compared HBsAg specific T cell responses of 24 monozygotic and 3 dizygotic twin pairs after HBsAg vaccination. Our results showed that the peptide binding assays did not…
The influence of major histocompatibility complex class II genes and T-cell Vbeta repertoire on response to immunization with HBsAg.
1998
Nonresponsiveness to HBsAg vaccination is observed in 5-10% of vaccine recipients and is possibly caused by a defect in the T helper cell compartment. The immune response to HBsAg is influenced by genes of the major histocompatibility complex. We have investigated MHC class I and class II antigens in 53 adult responders and 73 nonresponders. Results obtained in this first study were tested in a second study with 56 responders and 62 nonresponders from an infant vaccination trial. In addition, the peripheral Vbeta-chain T-cell receptor repertoire was investigated using monoclonal antibodies and flow-cytometry in 26 adult responders and 38 nonresponders. As previously reported, nonresponsiven…
HLA-DRB1*1301 AND *1302 protect against chronic hepatitis B
1997
Abstract Background/Aims: The outcome of acute hepatitis B infection may be influenced by host factors like the major histocompatibility complex (MHC). We have investigated MHC class I and class II antigens in patients with chronic hepatitis B compared to a healthy control population. To confirm the findings of this first study we performed a second study in a group of subjects who had spontaneously recovered from acute hepatitis B infection. Methods: Frequencies of MHC class I and class II antigens were analyzed in patients with chronic hepatitis B virus infection and in control subjects. MHC class I typing was done by standard microlymphocytotoxicity assays. DRB1 and DQA1 genotypes were d…
Update on autoimmune hepatitis
2009
Autoimmune hepatitis (AIH) is a necroinflammatory liver disease of unknown etiology that occurs in children and adults of all ages. Characteristics are its autoimmune features, hyperglobulinemia (IgG), and the presence of circulating autoantibodies, as well as a response to immunosuppressant drugs. Current treatment consists of prednisone and azathioprine and in most patients this disease has become very treatable. Over the past 2 years, a couple of new insights into the genetic aspects, clinical course and treatment of AIH have been reported, which will be the focus of this review. In particular, we concentrate on genome-wide microsatellite analysis, a novel mouse model of AIH, the evaluat…
Selective Depletion of Alloreactive T Lymphocytes Using Patient-Derived Nonhematopoietic Stimulator Cells in Allograft Engineering
2008
Background. Selective depletion of alloreactive T cells in vitro results in efficient graft-versus-host disease prophylaxis in allogeneic hematopoietic stem-cell transplantation, but it is accompanied by increased recurrence of leukemia. To spare donor T-cell-mediated graft-versus-leukemia immunity against hematopoiesis-restricted minor histocompatibility (minor-H) antigens, we explored the use of patient-derived nonhematopoietic antigen-presenting cells (APC) as allogeneic stimulators for selective allodepletion in leukemia-reactive donor T-cell lines. Methods. Primary keratinocytes, dermal fibroblasts, and bone marrow fibroblasts were generated from skin biopsies and diagnostic bone marro…
Establishment of standardised SLA/LP immunoassays: specificity for autoimmune hepatitis, worldwide occurrence, and clinical characteristics
2002
Background: Antibodies to soluble liver antigen/liver pancreas (SLA/LP) are specific markers of autoimmune hepatitis. Their target antigen has recently been cloned. Aims: To establish standardised immunoassays using the recombinant antigen, and to assess the frequency and significance of seropositivity in patients from different countries. Methods: An enzyme linked immunoassay was developed using purified recombinant antigen and validated by testing sera from 200 healthy blood donors and 1026 patients with various liver and non-liver diseases. The assay was then applied to 454 sera from 419 patients with autoimmune hepatitis from different countries. All sera were also tested by inhibition …
Increased age-associated mortality risk in HLA-mismatched hematopoietic stem cell transplantation.
2016
We investigated a possible interaction between age-associated risk and HLA-mismatch associated risk on prognosis in different age categories of recipients of unrelated hematopoietic stem cell transplants (HSCT) (n=3019). Patients over 55 years of age transplanted with 8/10 donors showed a mortality risk of 2.27 (CI 1.70–3.03, P<0.001) and 3.48 (CI 2.49–4.86, P<0.001) when compared to 10/10 matched patients in the same age group and to 10/10 matched patients aged 18–35 years, respectively. Compared to 10/10 matched transplantations within each age category, the Hazards Ratio for 8/10 matched transplantation was 1.14, 1.40 and 2.27 in patients aged 18–35 years, 36–55 and above 55 years. Model…
Disease-associated polymorphisms in ERAP1 do not alter endoplasmic reticulum stress in patients with ankylosing spondylitis
2014
The mechanism by which human leukocyte antigen B27 (HLA-B27) contributes to ankylosing spondylitis (AS) remains unclear. Genetic studies demonstrate that association with and interaction between polymorphisms of endoplasmic reticulum aminopeptidase 1 (ERAP1) and HLA-B27 influence the risk of AS. It has been hypothesised that ERAP1-mediated HLA-B27 misfolding increases endoplasmic reticulum (ER) stress, driving an interleukin (IL) 23-dependent, pro-inflammatory immune response. We tested the hypothesis that AS-risk ERAP1 variants increase ER-stress and concomitant pro-inflammatory cytokine production in HLA-B27(+) but not HLA-B27(-) AS patients or controls. Forty-nine AS cases and 22 healthy…
C4A deficiency and nonresponse to hepatitis B vaccination
2002
Hepatitis B vaccination failure has been linked to the presence of certain human leukocyte antigen class II alleles. However, the functional background of these associations has remained unclear. Complement component C 4 is encoded within the major histocompatibility complex and is essential for classical pathway activation.Healthy individuals (n=4269) were vaccinated in a prospective trial with Engerix B. Nonresponse was classified as anti-HBs10 U/l after the last vaccination. Seventy-three nonresponders (NR) (1.7%) were identified. For comparison 53 responders (R) (anti-HBs10 IU/l) were drawn randomly from the same cohort. C4 allotyping was carried out by high-voltage agarose gel electrop…