Effects of supernatants of polymorphonuclear neutrophils recruited by different inflammatory substances on mitogen responses of lymphocytes

Abstract

Two different substances, glycogen and thioglycollate, were used to recruit early peritoneal exudate cells (4 h). In the acute phase of the inflammatory response the cellular infiltrate is large, and the predominant cell (>95%) is the polymorphonuclear neutrophil. Supernatant had differing effects on lymphocyte responses to the mitogens PHA and LPS, also carried out in serum-free media, depending on recruiting substance and time of culture. While glycogen-recruited PMN supernatant (GPMN-S) always enhanced splenocyte responses to PHA, thioglycollate-recruited cells (TPMN-S) did not produce an enhancing factor until the cells had been in culture for 24 h. Whereas GPMN-S enhanced the splenocyte response to LPS only after 1 or 4 h of culture, TPMN-S failed to have any significant effect. Thymocyte responses to PHA were facilitated by all supernatants. Dilution of the soluble PMN factors resulted in a suppressive effect on splenocyte responses to both PHA and LPS, regardless of whether PMN were recruited by the thioglycollate or glycogen or of the time of cell incubation. These results indicate that PMN-rich cell populations of different types of activity are recruited by glycogen and thioglycollate and that these cells produce factors capable of potentiating, enhancing, or suppressing responses to T- or B-cell mitogens by normal syngeneic lymphocytes.