Histamine release from human pulmonary mast cells induced by bacterial antigens.

Antigens of four bacteria (Staphylococcus aureus, Haemophilus influenzae, Streptococcus viridans, Branhamella catarrhalis) were tested for their ability to release histamine from human pulmonary mast cells recovered by means of bronchoalveolar lavages. For the sake of comparison the action of bacterial antigens on human mesenteric and adenoidal mast cells obtained by enzymatic dispersion of the tissues was studied. BAL mast cells released histamine in response to all studied bacterial antigens. Haemophilus influenzae antigens were the most effective histamine releasers. From among three populations of human mast cells pulmonary mast cells were the most sensitive to the challenge with bacterial antigens. Mesenteric mast cells were markedly more reactive than adenoidal cells. Adenoidal cells had low sensitivity to bacterial antigens.