Effect of Lymphocytosis-Promoting Factor of Bordetella pertussis on the Immune Response

Abstract

Lymphocytosis-promoting factor (LPF) was obtained from culture filtrate of Bordetella pertussis and tested for its effect on the three well-defined cellular hypersensitivity reactions. The development of delayed-type skin reaction with tuberculin PPD and adjuvant disease in the rat was greatly suppressed by intracutaneous injections of a submicrogram dose of LPF. The rejection time of skin homograft in rats and mice was also prolonged by the treatment with LPF. The injection of LPF caused a striking lymphocytosis in the circulation and depletion of lymphocytes in the lymphatic tissues. It is suggested that LPF interacts directly with a selected population of lymphoid cells which participate in the development of cellular hypersensitivity.