SERUM AND CELLULAR FACTORS IN MURINE OBSTRUCTIVE-JAUNDICE

Background. The present experiments were performed to determine whethe r serum or cellular factors are responsible for the immune suppression observed in biliary obstruction. Methods. Male Lewis strain rats unde rwent bile duct ligation and division (BDL) or sham celiotomy (SC). Sp leen cells (splenocytes) and lymph node cells (lymphocytes) were isola ted 3 to 14 days later. Levels of direct and total serum bilirubin and total conjugated bile acids and response of BDL and SC splenocytes an d lymphocytes to concanavalin A (Con A) and phytohemagglutinin were me asured. Splenocytes from normal Lewis rats were then added to medium c ontaining 20 mu l, 40 mu l, and 100 mu l BDL or SC serum and incubated with Con A. BDL or SC splenocytes were injected into normal Lewis rat s, and splenocytes from those rats were studied 24 hours later (adopti ve transfer). Splenocytes from BDL and SC rats were separated into nyl on wool adherent and nonadherent fractions and incubated with Con A an d phytohemagglutinin. Results. The mitogenic response to Con A and phy tohemagglutinin was depressed in BDL splenocytes but normal in BDL lym phocytes. BDL serum suppressed the proliferative response of normal sp lenocytes, and adaptive transfer of cells produced immunosuppression. Removal of a nylon wool adherent fraction of cells restored the lympho proliferative response in BDL splenocytes. Conclusions. The blastogeni c response to phytohemagglutinin and Con A was decreased in BDL spleno cytes. This effect was tranferrable by both serum and cells. Removal o f a subpopulation of splenocytes corrected the defect.