KTPAF50, which was shown to be specifically expressed in the placenta, kidney (adult and fetal), pancreas and testis, while in the hematopoietic tissue this protein was detected in resting and activated CD8+ cells, resting and activated mononuclear cells, as well as in resting and activated CD19+ cells. The expression of KTPAF50 protein may be correlated with specific disease states, particularly in cancer and immune system disorders.