GM-CSF RAPIDLY PRIMES MICE FOR ENHANCED CYTOKINE PRODUCTION IN RESPONSE TO LPS AND TNF

Subcutaneous administration of Granulocyte-macrophage - colony stimula ting factor (GM-CSF) to mice enhanced LPS-induced cytokine production in the circulation (TNF, IL-6) and peritoneal cavity (TL-1 beta, IL-6) , This effect was induced rapidly (within 1 h) and persisted for 4 h, Mice made leukopenic with cyclophosphamide retained the ability to res pond to GM-CSE In addition, TNF induced IL-6 production was also enhan ced, These results demonstrate that GM-CSF has a pronounced priming ef fect on cytokine producing cells in vivo and raises the possibility th at this cytokine may contribute to the pathogenesis of septic shock.