Studies on histamine releasing factor (HRF) of human, murine and guinea-pig origin.

There has been the lack of small animal models for the studies of histamine releasing factor (HRF). We have found that HRF produced in vitro by lymphocytes of asthmatic patients can act independently from the animal species and induces histamine secretion from mouse peritoneal mast cells. We also found, that spleen cells derived from normal as well as from sensitized mice and guinea-pigs are able to generate HRF in vitro, when cultured in suitable conditions. HRF of mouse and guinea-pig origin released histamine from homologous mast cells in vitro and its activity was enhanced when spleen cell cultures were stimulated with specific antigens or non-specific mitogen.