Submitted to: Cellular Immunology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2005
Publication Date: 9/29/2005
Citation: Saalmuller, A., Lunney, J.K., Daubenberger, C., Davis, W., Fischer, U., Gobel, T.W., Griebel, P., Hollemweguer, E., Lasco, T., Meister, R. 2005. Summary of the animal homologue section of hlda8. Cellular Immunology 236:51-58.
Interpretive Summary: Understanding disease and vaccine responses is essential for animal health. In humans a large number of monoclonal antibody (mAb) define the immune cell differentiation antigens, termed CD antigens, expressed on cell subsets. In many animal species there are very few of these reagents. Testing mAb generated against one species for cross-reactivity on less well characterised species represents an excellent approach. Thus, for the latest human leukocyte differentiation antigen workshop (HLDA8) included an Animal Homologues section, to test mAb against human CD molecules for reactivity with cells from different animals. Our goal was to define and characterize cross-reacting mAb in order to increase the mAb repertoire in as many animal species as possible. Participating laboratories analyzed 377 commercially available anti-human CD mAb on cells from 16 different species – including non-human primates, ruminants, swine, horse, carnivores, rabbit, guinea pig, chicken, mink, and fish. In a first round 182 mAb showed reactivity with at least one species (48%). In a second round these FCM-results were confirmed by further analyses, affirming that there was broad species-overlapping reactivity of mAb directed against 14 different CD antigens and indicating evolutionary conserved epitopes on some of these surface molecules. The mAbs finally approved will be of great help for the area of veterinary immunology. However, the studies have shown that most of the mAbs showed very limited, or no, proven cross reactions on non-primate cells. So in many ways these results were disappointing for the lack of broad cross-species reactivity. Thus, further efforts to develop specific anti-CD mAb in veterinary species are required. Our immune toolkit needs to be improved.
Technical Abstract: Development of reagents against leukocyte differentiation antigens in veterinary immunology is slower compared to human and mice. Cross-reactivity studies with monoclonal antibodies (mAb) generated against human molecules represent an excellent approach for the detection of new reagents for the minor characterized species. For the latest human leukocyte differentiation antigen workshop (HLDA8) an Animal Homologues section was included. For this section 377 commercially available mAb from 15 different companies were tested for their reactivity with cells from 16 species – including non-human primates, ruminants, swine, horse, carnivores, rabbit, guinea pig, chicken and fish. In a first round 182 mAb (48%) showed reactivity with at least one of the species. Most of the cross-reactivity was found against non-human primate leukocytes. For some evolutionarily more distant species cross-reactive mAb showed a clear staining pattern in flow cytometry (FCM) for some mAbs. In a second round these FCM-results were confirmed by molecular analyses, by immunoprecipitation studies and analyses on transfectants. Interestingly there was broad species-overlapping reactivity of mAb directed against CD9 (11 out of 16 species), CD11a (10/16), CD14 (13/16), CD18 (12/16), CD29 (12/16), and CD49d, indicating evolutionary highly conserved epitopes on these surface molecules. Our results suggest the suitability of crossreactive mAb for the animal models studied. These findings contribute to our understanding of the evolution of the immune system. Supported by the Veterinary Immunology Committee of IUIS.