Expression levels of H-type alpha(1,2)-fucosyltransferase gene and histo-blood group ABO gene corresponding to hematopoietic cell differentiation.

Abstract

The expression of ABO antigens on the surface of RBCs is regulated by ABO gene-encoded ABO transferase activity after the formation of the H antigen. The molecular mechanisms that control the expression of the ABO blood group antigens along with erythroid differentiation are one of the most important subjects of study in transfusion science. FUT1(H), ABO, and beta 2-microglobulin mRNA were determined by semiquantitative RT-PCR from 27 hematopoietic cultured cell lines showing various differentiation stages and cell lineages and normal PBMNCs. The expression level of each cell was analyzed with computer software (Image, NIH) and was shown as the ratio of ABO mRNA or H mRNA to beta 2-microglobulin mRNA. The H antigen was also determined by immunocytochemical methods with flow cytometry in some cell lines. The highest expression of H mRNA was found in KOPM-28 and HEL cell lines and a lower expression was found in the mature cells. In contrast, it was observed that H antigen expression began at the level of HEL and PL-21 cells and increased with cell maturation. The highest expression of ABO mRNA was found in K-562 and KOPM-28 cell lines and it decreased along with cell maturation. Based on these results, it is concluded that the transcription of both H and ABO genes starts early in immature peripheral blood progenitor cells but gradually decreases during cellular maturation and also that the H antigen maintains a high level of expression thereafter. These results may reflect the active synthesis of H and ABO antigens in normal hematopoietic peripheral blood progenitor cells.