ABO typing in experimental cynomolgus monkeys using non-invasive methods

ABH antigens are not expressed on the red blood cells of monkeys, making it difficult to accurately determine their blood type. In this study, we evaluated the feasibility, convenience, and stability of two non-invasive methods for ABO typing (a reverse gel system assay and a buccal mucosal cell immunofluorescent assay) in cynomolgus monkeys (n = 72). The renal tissue immunofluorescent assay was used to obtain an accurate blood type in the monkeys. Using the reverse gel system assay and preabsorbed serum, we achieved accurate detection of ABO blood groups in 65 of the 72 monkeys but obtained confusing results in the remaining 7. The original immunofluorescent staining of the buccal mucosal smears clearly and correctly identified the ABO blood groups in 50 of the 72 monkeys. After repeated smearing and staining, the ABO group type could be correctly identified in samples from the rest of the monkeys, which were either lacking sufficient buccal mucosal cells or contained impurities. Based on our findings, we recommend the reverse gel system assay as the first choice for primate blood type analysis, and the buccal mucosal cell immunofluorescent assay as a Supplementary Method whenever the reverse gel system assay fails to give a clear result.