Ewing Tumor Associated Antigen 1 (ETAA1)

Northern blot analysis detected ETAA1 transcripts of about 3.5 kb in all EFT cell lines and biopsies examined. RT-PCR analysis detected ETAA1 in normal brain, liver, and kidney, but not in other tissues examined. Immunofluorescence flow cytometry and immunohistochemical analysis showed expression on the cell surface of 8 of 12 EFT cell lines examined, with lower cell-surface expression in a few non-EFT cell lines. Immunohistochemical analysis showed intracellular localization in liver and kidney that was restricted to epithelia of proximal tubules in kidney, a subset of lymphocytes in the B-cell corona of the marginal sinus of spleen, and the zona glomerulosa of adrenal gland, with weak staining of astrocytes in brain. Western blot analysis detected ETAA1 at an apparent molecular mass of 95 kD.