The use of cellulose carbonate-based immunoadsorbents in the isolation of minor allotypic components of rabbit immunoglobulin populations.

Cellulose trans-2,3-carbonate has been used as a new insoluble matrix for the simple coupling of a1- and b4-positive rabbit immunoglobulin to make immunoadsorbents capable of purifying from serum, with great efficiency, alloantibodies to these allotypic determinants. The antibodies have themselves been conjugated to prepare specific antibody immunoadsorbents of high binding activity for their allotypic target molecules. With these anti-allotypic solid-phase reagents it has been possible to affinity purify a1- and b4-positive immunoglobulin molecules and to deplete serum immunoglobulin of these molecules to leave in the eluates only the allotypically uncontaminated minor immunoglobulin components which are a-negative or b-negative (lambda chain-bearing) molecules. lambda chain molecules were also purified in very small quantities by affinity chromatography on a sheep anti-rabbit lambda chain column. This method of purifying minor populations of rabbit immunoglobulin from normal serum by special immunoadsorbent applications offers new opportunities to study the products of rarely expressed immunoglobulin genes in normal rabbits.