The recognition of virus-infected cells by class I MHC-restricted cytotoxic T cells requires endogenous processing of antigen for presentation. It is still unclear whether endogenous processing of antigen can be utilized by class II MHC molecules for presentation. To test this possibility, a human B cell line expressing HLA-A2 and HLA-DR1 was infected with a recombinant vaccinia virus expressin...

MHC class II molecules have a crucial role in thymic selection and in generating Ag-specific T cell responses. There is extensive evidence for second messenger generation via MHC class II molecules, which can lead to apoptosis of B lymphocytes. We have examined HLA class II-mediated apoptosis in both normal and tumoral human B lymphocytes. Phosphatidylserine exposure and DNA fragmentation were ...

The underlying etiological cause of non-hereditary colorectal cancer has yet to be determined. The adenoma-carcinoma sequence is widely accepted, however, a sole trigger has not been specified. Therefore, we sought to further define genotypic and phenotypic parameters that could be involved in promoting a possible infection, inflammation and hyper-proliferation, followed by the adenoma-carcinom...

Meiotic recombination does not appear to occur randomly across chromosomes, but rather seems to be restricted to specific regions. A striking example of this phenomenon is illustrated by the HLA class II region. No recombination within the 100 kb encompassing the DRB1-DQA1-DQB1 loci has been reported, whereas the random association of TAP1 with TAP2 alleles suggests the presence of a hotspot fo...

Background: The HLA class I molecules serve as ligands for both T cell receptors and killer cell immunoglobulin-like receptors (KIRs). Objective: We investigated the HLAC and HLA-Bw4 alleles as well as KIRs expression on CD56 positive lymphocytes to evaluate whether these genes and molecules could influence Ankylosing spondylitis (AS) susceptibility, alone or in combination. Methods: We typed 4...

We studied the presence of HLA class I antigens in 115 samples of bronchogenic carcinomas (66 frozen and 49 formalin-fixed and paraffinembedded specimens) by the immunophosphatase alkaline and immunoperoxidase methods with antibodies against major histocompatibility complex antigens. We also studied HLA class II antigens on the 66 frozen tumor samples. Nonneoplastic lung tissue was also analyze...

We studied the presence of HLA class I antigens in 115 samples of bronchogenic carcinomas (66 frozen and 49 formalin-fixed and paraffin-embedded specimens) by the immunophosphatase alkaline and immunoperoxidase methods with antibodies against major histocompatibility complex antigens. We also studied HLA class II antigens on the 66 frozen tumor samples. Nonneoplastic lung tissue was also analyz...

The precise role of human epidermal Langerhans cells (LCs) in immune response is highly controversial. While studying the gene expression profile of these cells, we were intrigued to identify the HLA-DQB2 gene as potentially expressed in LCs. Despite a strong evolutionary conservation of their sequences, the concomitant expression of the poorly polymorphic HLA-DQA2/HLA-DQB2 genes, paralogous to...

Following an acute hepatitis B virus (HBV) infection, clearance or persistence is determined in part by the vigor and breadth of the host immune response. Since the human leukocyte antigen system (HLA) is an integral component of the immune response, we hypothesized that the highly polymorphic HLA genes are key determinants of viral clearance. HLA class I and II genes were molecularly typed in ...

Polyclonal intravenous immunoglobulin (IVIg) treatment reduces crossmatch positivity and increases rates of transplantation in highly sensitised patients (HS). We quantified the panel reactive antibody (PRA) by microlymphocytotoxicity (MLCC), and we analysed anti-HLA class I and class II IgG specific antibody repertoire by Luminex before and after IVIg infusion alone in HS patients awaiting kid...