The mediation of tissue eosinophilia in hypersensitivity reaction. I. Isolation of two different chemotactic factors from DNP-Ascaris extract-induced skin lesion in guinea-pig.

In an active cutaneous anaphylaxis induced by DNP-ascaris extract in guinea-pig, tissue eosinophilia manifested two phases; the early and mild phase became maximal in about 6 h, while the delayed and intense phase in 18-24 h. Skin extracts from the lesions exhibited chemotactic activities for eosinophils, respectively comparable to the intensity of tissue eosinophilia in each phase; and two different chemotactic factors for eosinophils of skin extracts were separated by gel filtration on Sephadex G-100. The mediation of the early phase seemed to be associated with a thermostable factor with amolefular weight of less than 1400; this factor seemed to be related to mast cell degranulation. The mediation of the delayed phase appeared to be associated with a thermolabile factor with a molecular weight of about 70,000, probably independent of mast cell degranulation; the factor was considered to be more significant than the thermostable factor, because the delayed tissue eosinophilia was more intense than the early tissue eosinophilia.