REJECTION OF PRIMARILY VASCULARIZED HEART GRAFTS .3. DEPRESSION OF THE INTERLEUKIN-2 MECHANISM EARLY AFTER GRAFTING

The immunologic status of BIO.A recipients of primarily vascularized B10.BR heart grafts, which undergo temporary rejection but then generally survive long term, was investigated. Generation of cytotoxicity in mixed lymphocyte culture was moderately increased soon after grafting, as compared with naive mice, while mixed lymphocyte cultures did not reveal greater lymphocyte activation after grafting. Unexpectedly, the interleukin 2 mechanism was nonspecifically depressed 1 week after placement of the heart graft. This depressed interleukin 2 activity was restored essentially to normal in splenocytes, but it remained in effect in mesenteric lymph nodes, of long-term recipients with active heart allografts. © 1990 by Williams and Wilkins.