The structural heterogeneity among degraded gamma heavy chain disease proteins.

The amino terminal sequence of seven newly studied and three previously reported gamma Heavy Chain disease proteins show that they begin at several sites ranging from position 215--234 in the hinge region. The presence of more than one species of molecule in several of the sera and the susceptibility of this region to proteolytic cleavage, taken together with the finding of a blocked Heavy Chain disease protein in the serum of one and the cells of another patient support the concept that these molecules are the result of proteolytic cleavage of typical Heavy Chain disease proteins.