A ‘New’ Cromer‐Related High Frequency Antigen Probably Antithetical to WES

Abstract
An antibody to a high frequency antigen, made in a WES+ Black antenatal patient (Wash.), failed to react with the red cells of a presumed WES+ homozygote and is, therefore, probably antithetical to anti‐WES. Like anti‐WES, it reacted with papain, ficin, trypsin or neuraminidase treated cells but not with α‐chymotrypsin or pronase treated cells and was specifically inhibited by concentrated serum. It also reacted more strongly in titration with WES‐ cells than with WES+ cells. The antibody is Cromer‐related as it failed to react with Inab phenotype (IFC‐) cells and reacted only weakly with Dr(a‐) cells. Wash, cells and those of the other possible WES+ homozygote are Cr(a+) Tc(a+b‐c‐) Dr(a+) IFC+ but reacted only very weakly with anti‐Esa.