CD44 expression on normal renal tissue and RCC derived endothelial cells. Freshly isolated adherent cells of normal renal tissue (A and B) and RCC (C and D) were analyzed flow cytometrically and gated on EC FSC/SSC. Cells were stained with the NKI-P1 anti-CD44 (horizontal axis) antibody and counterstained with the EN4 EC-marker (vertical axis). Left panels represent conjugate controls. Mean fluorescence intensities of the endothelial cell subset is given in the upper right corner. The data of this patient are also given as RCC #7 in Table 1.