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T H Eiermann

Publications and source records attributed to T H Eiermann.

46 records · Page 3Linked to original sources

Mapping of an HLA-DRw52-associated determinant on DR beta 1 molecules.

The molecular reaction patterns of the DRw52-specific mouse monoclonal antibodies UL-52 and 7.3.19.1 were investigated. Upon immunoprecipitation and two-dimensional IEF-SDS polyacrylamide gel electrophoresis analysis (2D-PAGE) mAb UL-52 selectively isolated DR beta 1 molecules from DRw52-positive cell lines, whereas mAb 7.3.19.1 predominantly precipitated DR beta 3 molecules. Reduced mAb UL-52 binding affinity was observed to DRw8- and DRw12-positive cells, potentially resulting from structural modifications within the antibody binding site. Comparison of mAb UL-52 reactivity with published DR beta chain amino acid sequences demonstrates that the amino acid residues -S- in positions 11 and 13 on DR beta 1 molecules essentially contribute to the formation of the antibody binding site. mAb 7.3.19.1 reactivity, on the other hand, correlates with the expression of DR beta 3 chain amino acid residues K, G and N, in positions 71, 73 and 77, respectively. In contrast to other DRw52 monoclonal antibodies described so far, mAb UL-52 demonstrates a similar reactivity to DRw52 allosera, suggesting that mAb UL-52 and DRw52 allosera possibly recognize the same or a similar determinant on DR beta 1 molecules.

Amino Acid Sequence↗

Interleukin 2 production by alloantigen-stimulated CD4+ and CD8+ human T cell subsets: frequency of HLA class I or class II-reactive precursor cells and clonal specificity of activated T cells.

A recently developed limiting dilution (LD) method was used to analyze the frequency and specificity of IL2-producing cells within alloantigen-stimulated human CD4+ and CD8+ T cell subsets. Cell sorter-separated CD4+ and CD8+ responder cells were cocultured under LD conditions with HLA class I and/or class II different Epstein Barr virus (EBV)-transformed lymphoblastoid cells line (LCL) stimulator cells in the absence of additional factors. After 3 days, IL2 in cell-free culture supernatants was measured by a colorimetric assay on IL2-dependent murine CTLL cells. Under these conditions, one out of 200-500 CD4+ and one out of 300 to 1000 C8+ T cells produced IL2 when stimulated by HLA class I and class II disparate LCL. By using selected responder and stimulator cells differing only in HLA class I (A, B, C) or class II (DR) antigens, it was found that CD4+ T cells produced IL2 in response to HLA class II antigens, while CD8+ T cells produced IL2 in response to HLA class I antigens. Surprisingly, high frequencies of IL2-secreting CD4+ T cells were noted in certain HLA-DR-identical responder-stimulator combinations. To investigate whether HLA class II antigens other than DR (i.e., DQ or DP) activate CD4+ cells to IL2 secretion, we analyzed a set of HLA-A,B,C and -DR,DQ-identical responder-stimulator cells which differed only in DP antigens. In several of these instances, we measured high frequencies (f = 1/1000 to 1/2000) of HLA-DP-reactive CD4+ IL2 producers, while the frequencies in LD cultures stimulated with autologous LCL were low (f = 1/10,000 to 1/30,000). The specificity of alloantigen-activated IL2-secreting T cells was assayed by restimulation with the original or HLA-mismatched third-party LCLs. CD4+ responder cells could be efficiently and specifically restimulated to IL2 production after a resting period of 3 to 4 days, while CD8+ cells were refractory to restimulation under these conditions. Together these data demonstrate that: 1) CD4+ and CD8+ cells are stimulated to IL2 production by HLA class II and class I antigens, respectively; 2) alloantigen-activated CD4+ IL2 producers are highly specific for stimulating HLA antigens as shown by a split culture and restimulation approach; and 3) significant numbers of CD4+ IL2-producing T cells can be activated by selected HLA-DR-identical, DP-different stimulator cells.

Antigens, Differentiation, T-Lymphocyte↗

Monoclonal antibody to a supertypic determinant associated with HLA-DRw52.

A cytotoxic mouse monoclonal antibody UL-52 (IgG2b) was obtained after immunization of a BALB/c mouse with the lymphoblastoid cell line STA homozygous for HLA-A3, B8, Cw7, DR3, DRw52, DQw2, DPw2. Fluorescence analysis on a panel of B lymphoblastoid cell lines from the 10th International Histocompatibility Workshop 1987 showed almost exact concordance of UL-52 reactivity with the presence of the HLA-DRw52 antigen. Cytotoxicity testing of UL-52 on mononuclear cells of HLA-typed individuals revealed a pattern of reactivity closely associated with the HLA-DRw52 specificity as defined by conventional alloantisera (R = 0.77). UL-52 precipitated appropriate 29,000- and 33,000-dalton bands on SDS- polyacrylamide gels under reducing conditions from an HLA-DRw52 positive B lymphoblastoid cell line. Thus, by serological and biochemical criteria UL-52 defines a supertypic determinant associated with HLA-DRw52. In contrast to most DRw52- like monoclonal antibodies, UL-52 binds to DRw8 positive cells.

Animals↗

Generation and characterization of three new monoclonal antibodies detecting the allospecificities HLA-A2,w69, HLA-A3 and HLA-B13.

Immunization of balb/c mice with peripheral blood mononuclear cells of a leukemic patient possessing the antigens HLA-A2,3; B7,35 resulted in the polymorphic monoclonal antibody (moab) UL-101/68 (IgM) defining HLA-A3. Immunization of a second group of balb/c mice with the lymphoblastoid cell line BER homozygous for HLA-A2; B13 revealed two polymorphic moabs UL-39/10 (IgG3) specific for HLA-B13 and UL-39/24 (IgG2b) defining HLA-A2,w69. Immunoprecipitation and polyacrylamide gel electrophoresis with the two moabs of the IgG isotype confirmed the class I structure of the recognized antigens.

Acute Disease↗

MHC class II restricted self-recognition after allostimulation: clonal analysis.

After allostimulation in vitro using a combination of HLA-A, B, C, DR, DQ, D identical but HLA-DP different homozygous typing cells, 34 T cell clones were derived. Thirty-one of them were alloreactive clones, but three clones were found to be autoreactive. One of these autoreactive clones was further expanded. In order to characterize in more detail the determinant restricting the autologous response, a panel of HLA-typed peripheral blood mononuclear cells (PBMC) or Epstein-Barr virus lymphoblastoid cell lines (EVB-LCL) was typed. A good correlation of typing responses with the self haplotype HLA-A1, B8, Cw7, DR3, DRw52, DQw2 was found. Typing responses also segregated together with this haplotype in informative families. Blocking studies using MHC class I and II specific monoclonal antibodies (MoAb) linked the restricting determinant to MHC class II molecules. The clone which was both autoproliferative and autocytotoxic bore the CD3(+), CD4(+), CD8(-), Ia(+) phenotype. Antibiotics or foreign plasma proteins were ruled out as restricted determinants.

Antibodies, Monoclonal↗