A reverse hemolytic plaque assay for the detection and the enumeration of immunoglobulin allotype-secreting cells

We describe a reverse hemolytic plaque assay to enumerate rabbit immunoglobulin allotype-secreting cells. This technique makes use of sheep red blood cells (SRBC) sensitized with goat anti-rabbit IgG and rabbit anti-allotypic sera as revealing antisera. We have used the assay to compare at the IgG molecule level and at the immunoglobulin allotype-secreting cell level, the preferential expression (pecking order), in heterozygous rabbits, of one of the two alleles either at the a or the b locus, respectively, governing the a series allotypic specificities carried by the variable region of the heavy chains and the b series allotypic specificities essentially carried by the constant region of the K light chains.