Characterization of guinea pig lymphocyte-derived chemotactic factor for fibroblasts

An assay that measures guinea pig fibroblast chemotaxis in vitro is described. Application of this assay has revealed that stimulation of guinea pig blood or lymph node lymphocytes in vitro by T cell antigen (horseradish peroxidase) or mitogen (phytohemagglutinin) is associated with production of a chemoattractant for guinea pig fibroblasts. This lymphocyte-derived chemotactic factor for fibroblasts (LDCF-F) has a m.w. or 80,000 and is distinct from guinea pig lymphocyte-derived chemotactic factor for monocytes (LDCF-M). LDCF-F is heat labile and trypsin sensitive. The production of LDCF-F in vitro correlates with lymphocyte transformation to antigen or mitogen and with the presence of in vivo-delayed hypersensitivity to antigen. LDCF-F might function in vivo to attract connective tissue fibroblasts to sites of cell-mediated immune reactions.