[Monoclonal antibody typing of sub-populations of T lymphocytes in the blood and broncho-alveolar lavage (BAL) in sarcoidosis].

Cell typing of sub-populations of lymphocytes is facilitated by using monoclonal antibodies (OKT); with this technique we determined the relative proportions of "helper" T-lymphocytes (OKT4) and "Suppressor" T-lymphocytes (OKT8) in the blood and the LBA of 13 patients suffering from pulmonary sarcoidosis. In the control subjects the OKT4/OKT8 ratio was 1.9 +/- 0.3 in the blood (38 subjects) and of 2 +/- 0.2 in the LBA (6 subjects). Six patients suffering from inactive sarcoidosis (stabilised) had an OKT4/OKT8 ratio on average of 1.2 +/- 0.39 in the blood and of 1.86 +/- 0.46 in the LBA. By contrast in 7 patients suffering from "active" sarcoidosis, on average the ratio was 1.88 +/- 1.20 in the blood but 5.13 +/- 3.51 in the LBA; this ratio was notably raised in the LBA in 5 cases and was due as much to an increase in the T-"Helper" (OKT4) percentage as to a fall in the T-"Suppressor" (OKT8). It is probable that the T-"Helper" lymphocytes found in great numbers in the lung in active sarcoidosis cases participate in the formation of sarcoid granulomas and attract phagocytic mononuclear cells. This phenomenon seems to correspond to a local immune disturbance without producing a similar result in the peripheral blood of the patients.