Transferrin receptor (CD71) expression on circulating mononuclear cells during pregnancy.

Abstract

We studied transferrin receptor (CD71) expression in peripheral blood mononuclear cells from healthy pregnant women, to determine if a relationship existed between gestational age and circulating CD71+ mononuclear cells. Cell suspensions were prepared from venous blood from 139 pregnant women (7 to 26 weeks of gestation), incubated with monoclonal anti-CD71 antibody, and analyzed by flow cytometry. When only the first sample from each woman was analyzed, extensive biologic variation between women was shown. An apparent biphasic increase in the percentage of CD71+ cells with advancing gestation was suggested. A subgroup of 13 women studied on multiple occasions demonstrated linear increases in CD71+ cells as pregnancy progressed. Pregnant women, when compared with each other, may have differences in the baseline number of circulating CD71+ cells. The increases seen in individuals studied repeatedly are likely to reflect maternal hematopoiesis and current fetomaternal transfusion.