Differences in the binding, internalization and catabolism of low-density lipoprotein between normal human T and B lymphocytes.

Studies in human peripheral blood B and T lymphocytes show that high-affinity binding of low-density lipoprotein (LDL) to the cell surface receptor and the kinetics of binding are comparable between B and T lymphocytes, but the internalization of receptor-bound LDL in B cells appears deficient. Yet, the fraction of internalized LDL degraded by both B and T lymphocytes is of similar magnitude. Moreover, the lysosomal acid cholesterol ester hydrolase and acyl-CoA:cholesterol acyltransferase activities in B cell were about one-third of those in T lymphocytes. These data suggest deficient LDL catabolism in B lymphocytes relative to that in T lymphocytes.