CD28 and myelodysplastic syndrome: These results correspond to the observations in which increased hTERT expression and telomerase activity were detected in bone marrow in MDS patients [167], and the inducible (stimulated with CD3 and CD28) hTERT and telomerase activity in T cells of MDS were decreased compared to that of the control [168], which suggested that there are basal and inducible telomerase and hTERT splice-variant abnormalities in MDS patients.