Appearance of T-cell subpopulations during the time course of beryllium-induced granulomas.

Employing monoclonal antibodies that identify T-helper/inducer or T-suppressor/cytotoxic cells, we investigated the T-lymphocyte subsets in hypersensitivity granulomas developed after beryllium salt injection. T-helper/inducer cells were detected at all stages of the lesions, including early nonspecific inflammatory lesions seen at 3 weeks after injection. They formed clusters intermingled with the mononuclear phagocytes in granulomatous lesions, but were not found among the epithelioid cells. In contrast, T-suppressor/cytotoxic cells were slow to appear in the lesions and constituted very small numbers in mature epithelioid cell granulomas of 9-11 weeks. These findings suggest that T-helper/inducer cells may be responsible for the evolution of the perivascular infiltrate of mononuclear cells. Furthermore, appearance of T-helper/inducer cells without T-suppressor/cytotoxic cells may contribute to the development and organization of epithelioid cells and their maturity in the granulomatous lesions.