Acute renal rejection repeatedly activates immunocompromised CD8 + T cells. Maintained activation of CD8 + T cells can induce a process of replicative senescence. In the present study, we will evaluate in CD8 lymphocytes from patients undergoing acute renal rejection characteristics of replicative senescence such as: a) low expression of CD28 molecule; b) telomere shortening and c) increase production of proinflammatory cytokines. The study was carried out in CD8 + T cells from 14 patients transplanted without clinical evidences of acute renal rejection, 14 patients kidney transplanted with clinical and anatomopathological evidences of acute renal rejection, 8 healthy controls. The results shown that in peripheral blood and renal biopsy of patients with acute renal rejection there is a significant increment of the population of T cells CD28-CD8+, with short telomere length, as compared with healthy controls and patients without acute renal rejection. The presence of senescent cells was associated with high levels of IL-10 and IFN-Y in plasma and urine. In conclusion our study suggest that the CD8 + T cells of patients with acute renal rejection suffer a process of replicative senescence.