Shemyakin Institute of Bioorganic Chemistry RAS, Moscow, Russia.
Transfusion. 2012 Apr;52(4):860-9. doi: 10.1111/j.1537-2995.2011.03381.x. Epub 2011 Oct 7.
According to Landsteiner's law, alloantibodies are prevalent and autoantibodies are absent in the ABO blood group system. However, one study (Spalter et al., Blood 1999;93:4418-24) has suggested that low-affinity ABO autoantibodies, mitigated by anti-idiotypic immunoglobulins are also prevalent, while another publication (Rieben et al., Eur J Immunol 1992;22:2713-7) shows that humans do not have B-lymphocytes capable of producing immunoglobulin G ABO autoantibodies.
We used hapten-specific chromatography to isolate allo- and autoantibodies from pools of A or B serum and then characterized the resultant antibodies against a wide range of ABO and related glycoconjugates.
We found that the apparent autoantibodies are directed against blood group A or B disaccharides, without consideration for the presence of fucose, but requiring the absence of elongating sugar X in composition of Gal(NAc)α1-3(Fucα1-2)Galβ1-X-terminated carbohydrate chain. In contrast, ABO alloantibodies required a minimum trisaccharide Gal(NAc)α1-3(Fucα1-2)Gal epitope and recognize the elongated type-specific tetrasaccharides. Furthermore, alloantibodies appear to be a small set of specific yet crossreactive antibodies that detect all backbone types of A or B antigens, rather than being a collection of specific antibodies, each of which detects a different type of A or B antigen.
Apparent ABO autoantibodies appear to have no natural human target.
根据 Landsteiner 法则，ABO 血型系统中存在同种异体抗体而不存在自身抗体。然而，一项研究（Spalter 等人，Blood 1999；93:4418-24）表明，低亲和力 ABO 自身抗体也很常见，这些抗体受到抗独特型免疫球蛋白的抑制，而另一项出版物（Rieben 等人，Eur J Immunol 1992；22:2713-7）表明，人类没有能够产生 IgG ABO 自身抗体的 B 淋巴细胞。
我们使用半抗原特异性色谱法从 A 或 B 血清池中分离同种异体和自身抗体，然后用广泛的 ABO 和相关糖缀合物对所得抗体进行特征分析。
我们发现，表面自身抗体针对血型 A 或 B 二糖，不考虑是否存在岩藻糖，但需要 Gal(NAc)α1-3(Fucα1-2)Galβ1-X-末端碳水化合物链中不存在延伸糖 X。相比之下，ABO 同种异体抗体需要最小的三糖 Gal(NAc)α1-3(Fucα1-2)Gal 表位，并识别延伸的特定四糖。此外，同种异体抗体似乎是一组特异性但交叉反应的抗体，可检测 A 或 B 抗原的所有骨干类型，而不是一组特异性抗体，每种抗体检测不同类型的 A 或 B 抗原。
表面 ABO 自身抗体似乎没有天然的人类靶标。
