Previous studies demonstrated that BALB/c mice with the IgA-secreting plasmacytomas MOPC-315 (αλ2), MOPC-167 (ακ), McPC-603 (ακ) and TEPC-15 (ακ) developed large numbers of T cells with surface membrane receptors for IgA (Tα cells). The lack of Tα cell expansion in mice with variant plasmacytomas that were nonsecretors or low secretors of IgA implied that elevated serum IgA contributed to the increase in Tα cells. The present studies show that normal BALB/c mice that were given daily injections of 30 mg of IgA (M315 protein) develop a marked increase in the number of Tα cells. These studies also show that the Tα cells induced by injection of IgA are LY(t)1-2+ T cells. In addition, the data presented demonstrate that nylon wool nonadherent T cells, treated with purified polymeric IgA (M315 protein) in vitro, develop a marked increase in the number of Tα cells. The in vitro induction of Tα cells by IgA requires DNA and protein synthesis. These findings indicate that the Tα cell expansion observed in mice with IgA myeloma is related to the high serum level of IgA and not to the myeloma tumor per se. In addition, these observations have a more general relevance to the issue of B cell regulation because they demonstrate that secreted immunoglobulin can directly induce expansion of immunoregulatory T cells.
|Number of pages||4|
|Journal||Journal of Immunology|
|State||Published - Jan 1 1981|