Anti–HLA-E mAbs to the recombinant polypeptides of major HLA-E alleles (HLA-ER and HLA-EG). Anti–HLA-E mAbs did not react to HLA-F or HLA-G but did react to HLA class-Ia alleles anti–HLA-E mAbs. HLA-A* allelic reactivity of the anti–HLA-E mAbs (A); HLA-B* allelic reactivity of the anti–HLA-E mAbs (B); HLA-Cw* allelic reactivity of the anti–HLA-E mAbs (C). Anti–HLA-E mAbs reacting to HLA-F and HLA-G and also to all of the HLA class-Ia alleles (HLA-A, HLA-B, and HLA-Cw), mimicking the HLA-Ia and HLA-Ib reactivity of IVIg (D). These anti–HLA-E mAbs (D) are considered to be IVIg-mimetics because of the parallel HLA reactivity.