1998 Volume 9 Issue 4 Pages 113-118
To immunochemically determine molecular structural differences between three Tf subgroups (Tf-D · F1 · F2 · H2, Tf-O · R and Tf-X) and the relationships between equine Tf variants and donkey Tf, equine Tf types were subjected to binding assay with a panel of monoclonal antibodies (mAbs) specific to equine Tf-D, F, H2, O and R types and donkey Tf components. The results obtained were as follows: 1) Some mAbs produced against Tf-D and F type components showed group specific for only Tf-D · F1 · F2 · H2, and did not react with Tf-O, R, X types or donkey Tf component. As a result, Tf-D, F1, F2 and H2 could be immunochemically classified into the same group, but affinity for D variant differed within this subgroup. The F2 variant showed the strongest affinity for the D variant, followed by the F1 variant, then the H2 variant. 2) Group specificity for only Tf-O and R types was recognized in some mAbs produced against Tf-R type substance, Tf-O · R could thus be distinctly distinguished from Tf-D, F1, F2, H2 and X types. mAbs that react with Tf-O · R types, donkey Tf and Lf of horse and llama could also be developed. The Tf-R variant might be the most original Tf variant in equine Tf locus. 3) Antigen determinant of Tf-X variant differed from Tf-D · F1 · F2 · H2 subgroup and Tf-O · R subgroup, and X type formed an independent subgroup.