The effect of hydrocortisone and cyclosporin A on bacillus Calmette-Guérin epitheloid cell granulomas.

The injection of bacillus Calmette-Guérin (BCG) intradermally into the ear of guinea pigs leads to the formation in the draining lymph node of granulomas containing epithelioid cells with rough endoplasmic reticulum (RER) and an absence of phagocytosed material. BCG granulomas in hydrocortisone- or cyclosporin A (CsA)-treated animals contain mononuclear phagocytes with no RER. In CsA-treated animals, these cells contain fragments of phagocytosed organisms. CsA was given at two doses, 25 mg/kg orally and 50 mg/kg ip. The higher dose completely suppressed the delayed hypersensitivity (DH) response to purified protein derivative (PPD) but the lower dose did not affect the level of the DH response, but had a profound effect on epithelioid cell formation. The role of lymphokines in the maturation of the monocyte/macrophage to epithelioid cells is discussed.