ISSN:
1365-3083
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Tlymphocytes express multiple forms of the leukocyte-common antigen CD45, transcribed by alternative usage of leukocyte-common antigen exon 4 6. The various isoforms of CD45R expressed differentially on T cells are involved in different stages of development and activation. The monoclonal antibody (MoAb) RA3-6B2 is established as a B cell-type isoform (B220)-specific marker. However, it reacts with certain activated T cells although the relationship between 6B2 expression and T-cell activation is unclear. We have examined the 6B2 expression on activated T cells and found that concanavalin A, anti-CD3 antibody and staphylococcal enterotoxin B (SEB) induced 6B2 expression on T cells. The expression was found on both CD4+ and CD8+ T cells and also was induced by SEB in vivo predominantly on CD8+ T cells. The 6B2+ T cells are IL-2R+ and blasted cells according to flow cytometry analysis. Therefore, the 6B2+ T cells are supposed to be in an activated stage. Enzymatic analysis demonstrated that trypsin treatment decreased the 6B2 expression, whereas neuraminidase increased the intensity on activated T cells. Neither endo-D or endo-H have any effect on the expression and there are no differences, in the results of immunoprecipitation and RT-PCR analysis, between control T cells and activated T celts. Taken together, the 6B2 epitope is presumed to be the product of CD45R modification and is expressed on activated T cells. These results illustrate a novel classification of a T-cell subpopuiation bearing a 6B2 epitope.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3083.1994.tb03395.x
