Autoreactive T cell clones from mice infected with Mycobacterium bovis, strain Bacillus Calmette-Guérin (BCG). I. Phenotype, specificity and in vitro function.

Mice were infected with the intracellular microorganism, Mycobacterium bovis BCG, and draining lymph node cells were collected. A T cell line was established which was cultured in the presence of syngeneic accessory cells (AC) and killed BCG. Stimulation of this line depended on syngeneic accessory cells and did not require BCG as a source of antigen, indicating that it was autoreactive. T cell clones derived from this line had the L3T4 helper/inducer phenotype and reacted with self-Ia on syngeneic macrophages or B cell blasts. Cloned T cells were also stimulated by syngeneic accessory cells pretreated with the lysosomotropic agent chloroquine and by H-2 compatible, background gene disparate, accessory cells, suggesting that they were specific for self-Ia. After in vitro stimulation, the T cell clones secreted interleukin 2 (IL 2) and interferon-gamma (IFN-gamma), helped B cells in antibody production and activated macrophages for secretion of reactive oxygen metabolites.