Influence of an Acute Non-immunological Inflammation on Resistance to Infection and Neoplasia

Acute non-immunological inflammation was induced by injection of dextran or calcium pyrophosphate into the pleural cavity. Protection against Klebsiella pneumoniae and Trypanosoma cruzi infection in mice was observed. The increased resistance to K. pneumoniae was also obtained by intravenous injection of inflammatory serum to normal mice. Primary tumor growth and metastasis development could be either inhibited or enhanced according to the type of the tumor (the Lewis lung carcinoma in mice and a radio-induced hemangiosarcoma in rats) and the time of application of the phlogistic stimulus with respect to tumor grafting. Moreover, both inflammation and injection of inflammatory serum rendered peritoneal macrophage cytostatic for tumor cells and enhanced antibody-dependent cellular cytotoxicity of spleen cells. It appears from these results that : (1) a short lived inflammatory reaction may influence host defense mechanisms several days after its ending and (2) these effects are mediated by humoral factors released very shortly (2 hours) after the induction of the inflammatory process and to which we give the general name of phlogokines.