The ability of Fab'-anti-L3T4 A chain-containing immunotoxins to inhibit the helper function of keyhole limpet hemocyanin-specific T helper lymphocytes was evaluated. Keyhole limpet hemocyanin-specific T helper cells were prepared from the lymph nodes of primed mice and were enriched for T cells. Enriched populations of trinitrophenyl-specific B cells were prepared from spleens of normal mice. In the presence of antigen, the keyhole limpet hemocyanin-specific T helper cells were able to induce proliferation and differentiation of the trinitrophenyl-specific B cells. However, when the T helper cells were first treated with an immunotoxin composed of Fab' fragments of anti-L3T4 antibody coupled to ricin A chain (Fab'-anti-L3T4-A), they failed to induce proliferation and differentiation of the antigen-specific B cells. The concentrations of Fab'-anti-L3T4-A required to inhibit T cell help for the proliferation and differentiation of trinitrophenyl-specific B cells by 50% were 1 x 10-9 M and 4 x 10-10 M, respectively. Fab'-anti-L3T4 antibody alone did not inhibit T cell-induced B cell proliferation and differentiation by 50% at >100-fold higher concentrations.
|Original language||English (US)|
|Number of pages||5|
|Journal||Journal of Immunology|
|State||Published - 1987|
ASJC Scopus subject areas
- Immunology and Allergy