Lung-specific, cellular hypersensitivity was studied in patients with chronic pulmonary diseases. To do this, a leucocyte migration inhibition assay was performed using patient and control leucocytes incubated in the presence and absence of a soluble lung extract. Control antigens consisted of liver and kidney extracts. The immunological reactivity of these control antigens was tested by measuring migration, subsequent to incubation of leucocytes from patients with hepatic or renal disease with the liver and kidney extracts, respectively. As a second in vitro test of cell-mediated immunity, a lymphocyte cytotoxicity assay was performed, using as target cells normal chromium-labelled human lung cells.
Leucocyte migration inhibition was produced by the lung extract in four out of six patients with chronic bronchitis, five out of seven patients with tuberculosis, one out of five patients with sarcoidosis and in the single patient studied with rheumatoid lung disease. Inhibition did not occur with the leucocytes from control subjects. Neither was migration inhibited when leucocytes from the patients with lung disease were incubated with the control antigens. The reactivity of these control antigens was confirmed by the fact that leucocyte inhibition occurred in two out of three patients with hepatic disease, studied using the liver extract, and in two out of three patients with renal disease, studied with the kidney extract. The cytotoxic potential of anti-lung lymphocytes was demonstrated by the fact that significant target cell cytotoxicity occurred using lymphocytes from two out of four patients with chronic bronchitis, four out of five patients with tuberculosis and in two out of four patients with sarcoidosis.