CD4+ and CD8+ T cell subset distribution in the blood of small-bowel-grafted rats: modification during graft-versus-host disease.

We studied the modifications of blood T cell distribution following small-bowel allografting in rats under different experimental conditions. Group 1: ACI (RT1a) rats were used as small-bowel donors for ACI x Wistar (RT1y) F1 hybrid rats (WAF1) in which graft-versus-host disease (GVHD) developed. Group 2: WAF1 rats were used as small-bowel donors to ACI rats which developed rejection.

The anti-ischemic drugs defibrotide and oligotide analogously inhibit leukocyte-endothelial cell adhesion in vitro.

Defibrotide (a polydeoxyribonucleotide) and oligotide (an oligodeoxyribonucleotide) obtained from mammalian single-stranded DNA, have been demonstrated to have anti-ischemic activity in some experimental models of ischemia/reperfusion of kidney in rats. We hypothesized that their anti-ischemic activity could be related to an inhibition of leukocyte-endothelial cell adhesion and also the consequent generation of oxygen free radicals by leukocytes. We studied the in vitro adhesion of neutrophils to human umbilical vein endothelial cells under basal conditions and following neutrophil or endothelial cell activation (using 10(-7) fMLP and 500 U/ml TNF-alpha, respectively).