Watt S M, Bühring H J, Rappold I, Chan J Y, Lee-Prudhoe J, Jones T, Zannettino A C, Simmons P J, Doyonnas R, Sheer D, Butler L H
MRC Molecular Haematology Unit, Institute of Molecular Medicine, The John Radcliffe Hospital, Oxford, UK.
Blood. 1998 Aug 1;92(3):849-66.
CD164 is a novel 80- to 90-kD mucin-like molecule expressed by human CD34(+) hematopoietic progenitor cells. Our previous results suggest that this receptor may play a key role in hematopoiesis by facilitating the adhesion of CD34(+) cells to bone marrow stroma and by negatively regulating CD34(+) hematopoietic progenitor cell growth. These functional effects are mediated by at least two spatially distinct epitopes, defined by the monoclonal antibodies (MoAbs), 103B2/9E10 and 105A5. In this report, we show that these MoAbs, together with two other CD164 MoAbs, N6B6 and 67D2, show distinct patterns of reactivity when analyzed on hematopoietic cells from normal human bone marrow, umbilical cord blood, and peripheral blood. Flow cytometric analyses revealed that, on average, 63% to 82% of human bone marrow and 55% to 93% of cord blood CD34(+) cells are CD164(+), with expression of the 105A5 epitope being more variable than that of the other identified epitopes. Extensive multiparameter flow cytometric analyses were performed on cells expressing the 103B2/9E10 functional epitope. These analyses showed that the majority (>90%) of CD34(+) human bone marrow and cord blood cells that were CD38(lo/-) or that coexpressed AC133, CD90(Thy-1), CD117(c-kit), or CD135(FLT-3) were CD164(103B2/9E10)+. This CD164 epitope was generally detected on a significant proportion of CD34(+)CD71(lo/-) or CD34(+)CD33(lo/-) cells. In accord with our previous in vitro progenitor assay data, these phenotypes suggest that the CD164(103B2/9E10) epitope is expressed by a very primitive hematopoietic progenitor cell subset. It is of particular interest to note that the CD34(+)CD164(103B2/9E10)lo/- cells in bone marrow are mainly CD19(+) B-cell precursors, with the CD164(103B2/9E10) epitope subsequently appearing on CD34(lo/-)CD19(+) and CD34(lo/-)CD20(+) B cells in bone marrow, but being virtually absent from B cells in the peripheral blood. Further analyses of the CD34(lo/-)CD164(103B2/9E10)+ subsets indicated that one of the most prominent populations consists of maturing erythroid cells. The expression of the CD164(103B2/9E10) epitope precedes the appearance of the glycophorin C, glycophorin A, and band III erythroid lineage markers but is lost on terminal differentiation of the erythroid cells. Expression of this CD164(103B2/9E10) epitope is also found on developing myelomonocytic cells in bone marrow, being downregulated on mature neutrophils but maintained on monocytes in the peripheral blood. We have extended these studies further by identifying Pl artificial chromosome (PAC) clones containing the CD164 gene and have used these to localize the CD164 gene specifically to human chromosome 6q21.
CD164是一种新型的80至90kD粘蛋白样分子，由人CD34(+)造血祖细胞表达。我们之前的结果表明，该受体可能通过促进CD34(+)细胞与骨髓基质的粘附以及负向调节CD34(+)造血祖细胞的生长，在造血过程中发挥关键作用。这些功能效应由至少两个空间上不同的表位介导，这两个表位由单克隆抗体（MoAbs）103B2/9E10和105A5定义。在本报告中，我们表明，当对来自正常人骨髓、脐带血和外周血的造血细胞进行分析时，这些MoAbs与另外两个CD164 MoAbs（N6B6和67D2）表现出不同的反应模式。流式细胞术分析显示，平均而言，63%至82%的人骨髓CD34(+)细胞和55%至93%的脐带血CD34(+)细胞是CD164(+)，105A5表位的表达比其他已鉴定的表位更具变异性。对表达103B2/9E10功能表位的细胞进行了广泛的多参数流式细胞术分析。这些分析表明，大多数（>90%）CD38(lo/-)或共表达AC133、CD90(Thy-1)、CD117(c-kit)或CD135(FLT-3)的人骨髓和脐带血CD34(+)细胞是CD164(103B2/9E10)+。这种CD164表位通常在相当比例的CD34(+)CD71(lo/-)或CD34(+)CD33(lo/-)细胞上被检测到。与我们之前的体外祖细胞检测数据一致，这些表型表明CD164(103B2/9E10)表位由一个非常原始的造血祖细胞亚群表达。特别值得注意的是，骨髓中的CD34(+)CD164(103B2/9E10)lo/-细胞主要是CD19(+)B细胞前体，CD164(103B2/9E10)表位随后出现在骨髓中的CD34(lo/-)CD19(+)和CD34(lo/-)CD20(+)B细胞上，但在外周血的B细胞中几乎不存在。对CD34(lo/-)CD164(103B2/9E10)+亚群的进一步分析表明，最突出群体之一由成熟的红系细胞组成。CD164(103B2/9E10)表位的表达先于血型糖蛋白C、血型糖蛋白A和带III红系谱系标志物的出现，但在红系细胞终末分化时消失。这种CD164(103B2/9E10)表位的表达也在骨髓中发育的髓单核细胞上被发现，在成熟中性粒细胞上被下调，但在外周血单核细胞上维持表达。我们通过鉴定包含CD164基因的P1人工染色体（PAC）克隆进一步扩展了这些研究，并使用这些克隆将CD164基因特异性定位到人类染色体6q21。
