Cross-reactivity of rat, mouse, and human IgD.
Highly purified sheep anti-rat lymphocyte membrane IgD (mIgD) was used to detect cross-reactivity with the putative murine-delta chain on mouse lymphocytes. Cross-reactivity is demonstrated by indirect immunofluorescent staining and by immunoprecipitation of 125I-labeled lymphocyte membrane extracts followed by electrophoresis on 10% polyacrylamide gels. In addition, cross-reactivity of anti-rat-delta with human IgD is shown by gel diffusion analysis. The anti-rat-delta reagent stained both Ig5a+ and Ig5b+ lymphocytes. Preincubation of Ig5b+ (but not Ig5a+) cells with monoclonal allotype-specific antibodies (anti-Ig5b) under capping conditions caused inhibition of staining by the sheep anti-rat-delta reagent, indicating that it is the delta-chain that is recognized on mouse lymphocytes and that the anti-rat-delta reagents does not distinguish between mouse-delta allotypes. Furthermore, absorption of the sheep anti-rat-delta serum with purified human IgD reduced subsequent staining of mouse lymphocytes by approximately 50%; staining was not affected by absorption with human IgM. This xenogeneic anti-delta antiserum appears to detect determinants on the delta-heavy chain, which are shared by at least three species of mammals, suggesting that these determinants represent important molecular features conserved during evolution.
D000818:Animals; D000918:Antibody Specificity; D011232:Chemical Precipitation; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D005455:Fluorescent Antibody Technique; D006041:Goats; D006801:Humans; D007072:Immunoglobulin D; D007143:Immunoglobulin Heavy Chains; D007138:Immunoglobulin delta-Chains; D007152:Immunologic Capping; D051379:Mice; D008970:Molecular Weight; D051381:Rats; D011947:Receptors, Antigen, B-Cell; D012756:Sheep
D007072:Immunoglobulin D; D007143:Immunoglobulin Heavy Chains; D007138:Immunoglobulin delta-Chains; D011947:Receptors, Antigen, B-Cell