Schawalder Alissa, Reid Marion E, Yazdanbakhsh Karina
Immunochemistry Laboratory, New York Blood Center, New York, NY 10021, USA.
Transfusion. 2004 Apr;44(4):567-74. doi: 10.1111/j.1537-2995.2003.03297.x.
The Gerbich blood group system antigens are carried on glycophorin C (GPC) and glycophorin D (GPD) and variants thereof. These glycoproteins have been expressed in a heterologous system to study the individual antigens and to determine whether Ana is antithetical to Ge2.
cDNAs encoding GPC, GPD, GPC.Yus, GPC.Ge, GPC.Lsa, and GPD.Lsa were transfected and stably expressed in a human embryonic kidney cell line (293T). Individual Gerbich antigens were analyzed with MoAbs and human polyclonal antibodies by flow cytometry and immunoblotting. Recombinant GPD and GPD.Ana were expressed transiently and analyzed for expression of Ge2 and Ana antigens.
All recombinant variants were detected with sialidase-resistant and -sensitive anti-Ge2, anti-Ge3, and anti-Ge4. Ge4 antigen expression was depressed in GPC.Ls(a) transfectants as well as on Ls(a+) RBCs. GPD.An(a) recombinant protein expressed Ana and Ge2 antigens.
Cell lines stably expressing glycosylated Gerbich proteins were developed in a heterologous system by transfecting individual variant forms of GPC and GPD. Unexpectedly, it was found that Ge4 antigen is reduced in both the GPC.Ls(a) recombinant and the Ls(a+) RBCs. It was also shown that Ana and Ge2 antigens were expressed on a single GPD.An(a) protein and, therefore, they cannot be antithetical.
杰尔比希血型系统抗原存在于血型糖蛋白C（GPC）和血型糖蛋白D（GPD）及其变体上。这些糖蛋白已在异源系统中表达，以研究单个抗原，并确定Ana是否与Ge2为对偶抗原。
编码GPC、GPD、GPC.Yus、GPC.Ge、GPC.Lsa和GPD.Lsa的cDNA被转染并稳定表达于人类胚胎肾细胞系（293T）中。通过流式细胞术和免疫印迹法，用单克隆抗体（MoAbs）和人多克隆抗体分析单个杰尔比希抗原。重组GPD和GPD.Ana被瞬时表达，并分析Ge2和Ana抗原的表达情况。
所有重组变体均能用对唾液酸酶耐受和敏感的抗Ge2、抗Ge3和抗Ge4抗体检测到。Ge4抗原在GPC.Ls(a)转染细胞以及Ls(a+)红细胞上的表达降低。GPD.An(a)重组蛋白表达Ana和Ge2抗原。
通过转染GPC和GPD的单个变体形式，在异源系统中建立了稳定表达糖基化杰尔比希蛋白的细胞系。出乎意料的是，发现Ge4抗原在GPC.Ls(a)重组体和Ls(a+)红细胞中均减少。还表明Ana和Ge2抗原在单一的GPD.An(a)蛋白上表达，因此它们不是对偶抗原。
