Studies on delayed hypersensitivity pleural exudates in guinea-pigs. II. The interrelationship of monocytic and lymphocytic cells with respect to migration activity.

The in vitro migration activity of monocytic cells and the effect of lymphocytes in the delayed hypersensitivity (DH) reaction induced by intrapleural injection of PPD into FCA-sensitized guinea-pigs was investigated. The in vitro migration of exudate mononuclear cells was lower than that of comparable blood cells, and continued to decrease as the reaction progressed. An inverse relaationship was observed between the migration area and cell volume of mononuclear cells from both blood and exudate. Similar experiments were performed on the reversed passive Arthus (RPA) reaction in the pleural cavity of guinea-pigs. For 6-h exudate, the mononuclear cell migration exceeded that for blood mononuclear cells. However, the migration of mononuclear cells from 18-h exudates was markedly reduced. As with DH, an inverse relationship between the migration area and cell volume was observed with the mononuclear cells of RPA exudates. Following the addition of antigen, the migration of DH exudate mononuclear cells was inhibited whereas the exudate mononuclear cells of the RPA reaction remained unaffected. For DH, the inhibition of migration induced by antigen appeared to be related to the non-adherent cells of 6-h exudates, and both the adherent and non-adherent cells of 18-h exudates.