Tiam Mana Saffari

115 THE LOCAL MICROENVIRONMENT OF NERVE ALLOGRAFTS AFTER ANGIOGENESIS 6 RESULTS Peripheral T cells To understand systemic levels of inflammation, we examined classical T cell markers in blood samples. After one week, T helper population (CD4) was significantly increased in SIEF rats (59.7±1.0%), compared to baseline, untreated rats (47.4±4.3%, P=0.02). CD4 cells measured 58.6±3.0% in autografts and 54.8±3.5% in allografts at one week, respectively. At two weeks, CD4 decreased to 48.9±5.8% in autografts, 57.1±4.0% in allografts and 56.7±1.1% in SIEF rats, respectively (P=0.10). CD8 cells measured 23.2±1.2% and 21.7±3.0% in autografts, 22.2±1.0% and 22.8±1.2% in allografts and 22.7±0.2 and 23.7±0.9% in SIEF rats, at one and two weeks, respectively. No significant differences in proportions of T cytotoxic/suppressor populations (CD8) were seen, compared to baseline (26.2±1.9%, P>0.10), or between time points (P=0.20, Figure 1). These results indicate that CD4-positive T helper cells are selectively elevated in SIEF rats. Figure 1. Helper T cells (CD4) and cytotoxic T cells (CD8) in peripheral blood. Percentage of live cells in control (baseline) rats and rats in which the 10- mm sciatic nerve gap has been repaired with autograft, allograft and allograft wrapped around with a superficial inferior epigastric artery fascial (SIEF) flap to provide vascularization, at one week and two weeks post-surgery. Bars denote mean ± SEM. *Indicates significance at P < 0.05. SEM: Standard error of the mean.