Inhibition of endothelial cell proliferation by ▵120-calreticulin. Fetal bovine heart endothelial cells (800 cells/well) were cultured for 5 days in medium alone or medium supplemented with bFGF (25 ng/mL). Recombinant purified MBP-calreticulin, MBP–▵120-calreticulin, or MBP were added to bFGF-supplemented cultures. Proliferation was measured by³H thymidine incorporation during the final 20 to 23 hours of culture. The results reflect the mean of triplicate cultures; SDs within 12% of the mean.