Specificity of recombination of H and L chains from human gamma-G-myeloma proteins

Dissociated H and L chains of human gammaG-myeloma proteins were recombined by removal of conditions interrupting non-covalent interactions. In the process of recombination 7S molecules were formed. It was demonstrated that the H chains from individual gammaG-myeloma proteins recombine with their own L chains but also with L chains derived from other myeloma proteins. In some instances, however, the L chains from other myeloma proteins did not recombine as avidly with the H chains as the autologous L chains. The specificity of the non-covalent interactions of H and L chains was particularly well brought out by competitive recombination experiments where an individual H chain had a choice of recombining with its own L chain or with the L chain obtained from another myeloma protein. In this manner a spectrum of affinities between individual H chains and several L chains was demonstrated. In the vast majority of recombinations there was a clearcut preference for recombination to take place between the H and L chains derived from the same protein. It is postulated that this specificity is related to differences in the primary structure, which cause differences in configuration of these homogeneous H and L chains and that these configurations then dictate on thermodynamic grounds the pairing of H chains with particular L chains.

Phylogeny of the Immune Response

The immune response of turtles to giant keyhole limpet hemocyanin was studied by means of the precipitation of I*-hemocyanin by antiserum. The pertinent findings were: The 18 S protein constitutes 13 to 26% of the total normal serum protein in the turtle.In an antibody response rapidly sedimenting antibody predominates for the first month and is gradually replaced by slowly sedimenting antibody.The slowly sedimenting antibody activity as well as that of the rapidly sedimenting antibody activity is almost entirely destroyed by 2-mercaptoethanol treatment.No anamnestic response occurred.The precipitin reaction between turtle antibody and antigen remains, throughout the course of immunization, similar to a mammalian primary response in that it is greatly effected by dilution of the test system.

Studies on the Heterogeneity of the Rate of Combination of Antibody with Antigen

By means of separating antisera into fractions with different rates of association, it has been demonstrated that rabbit anti-BSA is heterogeneous with respect to its rate of combination with antigen. This separation was accomplished by: a) fractionation according to total molecular charge; b) rapid, partial absorption with a particulate BSA preparation; c) partial in vivo clearance of anti-BSA with antigen. It was possible to select antibody molecules on the basis of their combination rate without a significant alteration in the dissociation rate, thereby indicating that these two processes are, at least in part, independent of each other.