The effects of anticoagulants and other drugs on cellular and cutaneous reactions to antigen in guinea-pigs with delayed-type hypersensitivity.

Delayed-type hypersensitivity to tuberculin was induced in guinea-pigs by vaccination with BCG. The effects of several drugs on the responses of peritoneal exudate cells to tuberculin (PPD) and on delayed skin reactions to PPD were investigated. In untreated animals intraperitoneal injections of PPD were followed by the virtually complete loss of macrophages from the exudates (the macrophage disappearance reaction), the partial loss of lymphocytes and a marked increase in the number of polymorphs in the exudates. The macrophage disappearance reaction was markedly or completely inhibited in animals treated with the anticoagulant drugs heparin or sodium warfarin, very slightly inhibited in animals treated with cortisone acetate or promethazine and not inhibited in animals treated with reserpine. The other peritoneal cellular responses were variably but only slightly affected by these drugs. Delayed skin reactions to PPD were partly inhibited in animals treated with heparin, sodium warfarin or cortisone acetate and more strongly inhibited in animals treated with a combination of sodium warfarin and cortisone acetate. Histological examination of the skin test sites of untreated animals and of animals treated with sodium warfarin and/or cortisone acetate showed that the accumulation of macrophages was more markedly inhibited in animals treated with sodium warfarin than in animals treated with cortisone alone. No correlation could be established between the effect of treatment with sodium warfarin on the macrophage disappearance reaction, on blood coagulation and on serum complement levels.