CD4⁺CD25⁻Nrp1⁺ T cells induce hyporesponsiveness of the T effector cells.

<p>CD4⁺CD25⁻ T cells were isolated from spleens of recipient mice treated by Rapamycin combined with CD4⁺CD25⁻Nrp1⁺ T cells and from syngeneic transplant recipients on day 70 after transplantation, then primed with irradiated BALB/c (donor) splenocytes in the presence or absence of exogenous IL-2 (100 U/ml). (<b>A</b>) Cell proliferation was determined by ³H thymidine incorporation. (<b>B</b>) Cytokine content of the mixed lymphocyte reaction supernatants with no exogenous IL-2 treatment was evaluated by enzyme-linked immunosorbent assay. Results are presented as mean ± SD values of triplicate wells, and are representative of 3 independent experiments. *P<0.05, **P<0.01, ***P<0.001. SC = syngeneic controls, ³H-TdR = metabolic incorporation of tritiated thymidine, cpm = cells per million, Nrp-1 = neuropilin-1, rapa = Rapamycin, CTR = control, NS = not significant.