Phenotypic properties and cytokine production of skin-infiltrating cells obtained from guinea pig delayed-type hypersensitivity reaction sites.

In this study, skin-infiltrating cells were prepared from guinea pig delayed-type hypersensitivity reaction sites, and their phenotypic properties and cytokine production were examined. Our cell preparations contained around 45% nonspecific esterase-positive cells and a few skin-derived cells. Skin-infiltrating cells produced TNF activity and macrophage chemotactic activity (MCA), whereas resident skin cells produced much lower activity. The highest TNF activity was produced by skin-infiltrating cells at 2 hr after antigen injection. In contrast, a larger amount of MCA was produced by skin-infiltrating cells at 24 and 48 hr than at 2 hr after antigen injection. These kinetics were in good agreement with our previous results regarding cytokine activity in skin extracts. Gel filtration analysis and neutralization assay with a monoclonal antibody against human macrophage chemotactic factor with a molecular weight of 1 kDa (MCF-1) indicated that a guinea pig homologue of human MCF-1 was partially responsible for the MCA.