A macrophage chemotactic factor sharing common antigenicity with immunoglobulin G from DNP-ascaris extract-induced...

A macrophage chemotactic factor (factor a) was extracted from DNP-ascaris extract-induced skin lesions (showing a maximal macrophage reaction) in guinea-pigs and then purified by gel filtration on Sephadex G-100 and chromatography using DEAE-Sephadex and CM-Sephadex. This material was a thermolabile protein (free of nucleic acid) with a molecular weight of about 150,000. It shared commom antigenicity with serum IgG, and its chemotactic acitivity was completely absorbed by anti-IgG and anti-light chain antibodies, but not by anti-BSA antibody. In contrast to leucoegresin, this material seemed active for macrophages but not for neutrophils. Less active factors b and c were thermostable and not absorbed by the antibodies described above. The ratio of chemotactic activity of factors a, b and c in the skin extracts was roughly 60:25:15.