CD3 polymorphism in cynomolgus monkeys (Macaca fascicularis)

Cynomolgus monkeys were divided into two groups in terms of the reactivity of their lymphocytes with the FN18 monoclonal antibody, which is directed t o the CD3 of rhesus monkeys. It was shown that 24 (12.2%) out of 196 monkey s did not have lymphocytes that reacted with the FN18, although T cells fro m those animals responded well to mitogenic stimulation. We have determined the nucleotide sequences of the CD3 delta, CD3 gamma, and CD3 epsilon chai ns and found that two amino acids of the CD3 epsilon, chain of the FN18 non -reactive monkeys were different when compared with the FN18 reactive monke ys. Our results indicated that the CD3 epsilon molecule of cynomolgus monke ys is polymorphic at the epitope level, which is recognized by the FN18 mon oclonal antibody.