Lymphocyte chemotaxis in inflammation. III. Demonstration of lymphocyte chemotactic activity in extract from PPD-induced delayed hypersensitivity skin reaction site in the guinea-pig.

Various skin extracts from inflammatory lesions in guinea-pigs were assayed for chemotactic activity for guinea-pig lymphocytes; distinct chemotactic activity was shown in extract from PPD-induced delayed hypersensitivity reaction sites, and the time-course of chemotactic activity almost paralleled the intensity of lymphocyte reaction in skin sites. However, extracts obtained from various control sites or passive Arthus reaction sites exhibited little chemotactic activity for the cells. It is therefore suggested that lymphocyte chemotactic factor(s) was produced in the soluble form in the delayed hypersensitivity reaction.