OBJECTIVE: Intimal hyperplasia (IH) remains one of the major obstacles to long term vein graft patency. IL-1B has been demonstrated to be one of the first inflammatory cytokines expressed in the rat vein graft model of IH and may be an important initiator of the sequence of events leading to the development of IH. This study was designed to establish the role of IL-1B by demonstrating the outcome of inhibiting its effects by the use of neutralizing antibodies on the development of IH in this model.

METHODS: Rat epigastric vein to femoral artery interposition grafts were treated with neutralizing antibody to IL-1B suspended in pluronic gel and harvested at the end of one week and two weeks. The amount of intimal hyperplasia was measured at the anastomotic and midgraft regions.

RESULTS: The amount of IH was less at the anastomotic and midgraft regions of the treated grafts at the end of one week (p<0.05), but did not differ significantly with the untreated group at the end of two weeks.

CONCLUSION: Neutralizing antibody to IL-1B delivered locally retarded but did not prevent the occurrence of IH in vein grafts. The initiation of the cascade of events in the development of IH is affected in a major way , but not singularly by IL-1B