Studies on the interaction of concanavalin A with major density classes of human plasma lipoproteins. Evidence for the specific binding of lipoprotein B in its associated and free forms.

Normal human plasma lipoprotein system consists of four distinct lipoprotein families referred to as LP-A,* LP-B, LP-C, and LP-D [l-4]. In the density above 1.019 g/ml, the lipoprotein families occur mainly as separate physicochemical entities [3, 51. However, in the density below 1.019 gJrn1 the lipoprotein families B and C and, if present, lipoprotein families A and D form an association complex(es) [2, 51. In a continuing effort to develop simpler procedures for the isolation and separation of free and associated forms of lipoprotein families, we have