Effect of tumor necrosis factor-alpha and interleukin-2 on spleen lymphocyte migration in mouse skin

Tumor necrosis factor-alpha (TNF-alpha) and interleukin-2 (IL-2) are report ed to enhance lymphocyte binding to endothelial cells in vitro. We examined these two agents on lymphocyte migration in vivo. Spleen lymphocytes were radiolabeled,with tritiated uridine (3H-UR) and then injected IV into mice. Each cytokine (TNF-alpha or IL-2) or both cytokines were then injected int radermally on the back of mice. The results demonstrated that TNF-alpha sti mulates lymphocyte migration in vivo in dose-dependent fashion. Kinetic ana lysis demonstrated that migration with TNF-alpha started at 3h, peaked at 6 h, followed by a gradual decline back to baseline at 24h. IL-2, on the othe r hand, was nearly inactive, and did not augment lymphocyte migration over and above that induced by TNF-alpha when both cytokines were injected toget her.