β1-Integrin–mediated adhesion to hr90K protects lymphoma cells from chemotherapy-induced apoptosis.

Jurkat T-lymphoma cells were seeded in the absence (▪) or in the presence (■) of precoated hr90K. Then increasing concentrations of doxorubicin (A) or cyclophosphamide (B) were added. Apoptosis was determined by propidium iodide–macridine orange or Giemsa staining. Each point represents the mean ± SEM of 3 independent experiments. (C) The effect of doxorubicin (10 μmol/L) on Jurkat T-cell apoptosis in the absence of coating protein (−) and the BSA or hr90K in the presence or absence of the function-blocking antibody 4B4. Each bar represents the mean ± SEM.