Cellular reaction induced by “nonantigenic” substances

A previously designed isotopic in vivo method for measuring delayed hypersensitivity was used with nonantigenic (or weakly antigenic) phlogogenic substances. A strong reaction was observed in some circumstances, witnessing the fact that the method has a specific and a nonspecific component. The reaction is drastically augmented by a mild whole-body irradiation of the reacting animals. In the case of the studied substances (carbon, oil and bentonite) the reaction is bound by polymorphonuclear neutrophils (PMN), but it was found to be independent of the number of circulating PMN in the blood.