Biochemical comparison of HLA‐DR molecules derived from autologous human T and B lymphoblasts

Abstract

Earlier findings that human activated T blasts display HLA-DR determinants have been confirmed. After phytohemagglutinin activation, Percoll gradient-purified blast cells were cultured for two weeks in mitogen-derived supernatants from human lymphocyte cultures. Using purified T blasts and internal labeling procedures, it was established that T blasts actively produced HLA-DR-like chains, as assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Further, HLA-DR chains obtained from Epstein-Barr virus-transformed B cells and from T blasts of the same donor were compared. Two-dimensional gel electrophoretic comparisons indicated a striking homology between 29 kD and 35kD chains, obtained from the two different cell types. Peptide map analysis and preliminary amino acid sequence comparisons further supported this similarity. A more complete analysis would, however, be required to prove actual identity. The fact that human T blasts produce and display HLA-DR molecules very similar, if not identical, to those present on B cells must then be incorporated into models discussing major histocompatibility complex-restricted collaborations involving HLA-DR molecules.

Two allelic forms of mouse beta 2-microglobulin.

“…Two forms could be distinguished by virtue of their different mobilities and, for convenience, the faster and slower migrating forms were provisionally named ",32mf" and "832ms," respectively. To determine the strain distribution of 832m alleles, 10 .82m Phenotypes of Heterozygotes. To determine whether mice heterozygous for f2m express both forms of the protein, P2m were isolated from labeled extracts of C57BL/10 (p2mf) X A/J (12ms) spleen cells.…”

“…Tryptic digestion was performed in 0.2 M N-ethylmorpholine buffer (pH 8.1) for 3 hr at 370C at a trypsin/protein ratio of 1:20 (DPC-trypsin, Sigma). Peptides were separated on a Ci8 column (Bondapak) with a 5-60% ethanol gradient containing 5 mM ammonium trifluoracetate (10 …”

Replication of Herpes Simplex Virus in Human T Lymphocytes

“…Nevertheless, the EBV-transformed B-cell line B95-8 actively replicates HSV upon infection, as assessed by multiple experiments (data not shown). This point might be of further interest, since EBVtransformed B cells display HLA-DR deter minants of striking homology to HLA-DR antigens expressed by a subset of activated T cells [28]. It might be that expression of these la determinants is somehow related to the ability of lymphocytes to replicate HSV.…”

HLA‐DR Antigens: Structure, Separation of Subpopulations, Gene Cloning and Function

“…The DR antigens and the analogous murine Ia antigens are found primarily on B lymphocytes and monocytes, but have also been detected on a variety of other somatic and tumor cells. Normal resting T cells express little or no DR but upon activation they synthesize a DR antigen which is serologically and structurally identical to that found on B cells (Albrechtsen et al 1977, Evans et al 1978, Fu et al 1978, Altevogt et al 1980. The murine I region is known to encode at least two la-like antigens.…”