32% dextran 70 (Hyskon) inhibits lymphocyte and macrophage function in vitro: a potential new mechanism for adhesion prevention

Thirty-two percent dextran 70 (Hyskon, Pharmacia Laboratories, Piscataway, NJ) is reported to be efficacious in the prevention of postoperative adhesions, however, the precise mechanism of action remains unclear. Activated macrophages and T-lymphocytes play an important role in postoperative wound healing and adhesion formation. The purpose of this study was to determine the effects of Hyskon on lymphocyte and macrophage activity in vitro. Peripheral blood mononuclear cells and peritoneal fluid leukocytes were isolated from infertile women and fertile controls. Lymphocyte proliferation was assessed by hemocytometer cell counts and 3H-thymidine incorporation. Macrophage function was determined by phagocytosis of fluorescent microspheres. Hyskon significantly inhibited lymphocyte proliferation and macrophage phagocytosis in all groups. Hyskon did not affect cell viability as determined by trypan blue exclusion. The results of this study indicate that Hyskon has immunosuppressive effects in vitro suggesting a new mechanism by which Hyskon may reduce postoperative adhesion formation.