Histamine release from mast cells of various species induced by histamine releasing factor from human lymphocytes

The aim of our work was to investigate the effect of histamine releasing factor (HRF), produced in vitro by lymphocytes obtained from atopic and non-atopic asthmatics, on mast cells of various species (mouse - peritoneal mast cells, hamster and rat - peritoneal and pleural mast cells, guinea-pig - mesenteric and pulmonary mast cells). We found that human HRF is able to release histamine from the examined mast cell populations in a dose-dependent fashion. Mast cells from various species differed in their susceptibility to the action of HRF; rat pleural and guinea-pig mesenteric and pulmonary mast cells were the most susceptible, while mouse and hamster peritoneal mast cells - the least susceptible. The presence of 50% D2O in the medium significantly increased HRF-induced histamine release from rat mast cells, while the addition of phosphatidylserine did not change it. HRF-induced histamine release from guinea-pig mesenteric mast cells was not related to sensitization of these cells. We also compared histamine release from guinea-pig pulmonary and mesenteric mast cells induced by human HRF produced in vitro by lymphocytes obtained from atopic and non-atopic asthmatics. We have found that supernatant from atopic asthmatics lymphocyte cultures released significantly more histamine than supernatant from non-atopic asthmatics lymphocyte cultures. Our studies give evidence that human HRF acts across the species barrier and induces histamine release from mast cells of various species. The mechanism of HRF action on mast cells seems to be different from that of allergen.