Specificity: The antibody JSB-1 reacts with a conserved cytoplasmic epitope of the plasma membrane-associated 170-180 kD glycoprotein, the expression of which is strongly correlated with the degree of multi-drug-resistance (MDR) derived MDR cell lines and human MDR cell lines, including cell lines derived from lung, ovaries and B cell lymphomas. Cross-reacts with Chinese hamster. No cross-reactivity with mouse or rat.