Antibodies specific for the blood group ABO system antigens are of clinical significance and immunological interest. Routine clinical methods typically employ direct or indirect haemagglutination methods to measure IgM and IgG, respectively. We have developed a simple, single tube method to quantify IgM, IgG, and IgA specific for A and B antigens in order to improve accuracy and reproducibility, and to investigate the relationships between ABO group antibody type, and antibody level.

Plasma samples from 300 healthy blood donors were studied. Levels of IgM and IgG binding to reagent group A and B red cells were measure by agglutination (HA) and multi-colour flow cytometry (MC-FC). IgA was also measured by MC-FC.

Our FC method was found to be significantly more reproducible than HA for the measurement of blood group A and B specific antibodies. We found statistically significant correlations between antibodies measured by GC-HA and MC-FC, but sufficient differences to indicate that these methods are not equivalent. By MC-FC, IgM, IgG and IgA levels and isotope profiles were found to be dependent on both the donor ABO type and the specificity of the antibody.

This study demonstrated heterogeneity in the immunoglobulin class profiles of ABO-blood group specific antibodies within the healthy population. Differences in isotype profiles of ABO-blood group specific antibodies may indicate fundamental differences in the immune mechanisms that generate these antibodies. This is likely to be relevant to the clinical situations where management or diagnosis depend on ABO-specific antibody detection and measurement.

对血型 ABO 系统抗原具有特异性的抗体具有临床意义和免疫学意义。常规临床方法通常采用直接或间接血细胞凝集方法分别测量 IgM 和 IgG。我们开发了一种简单的单管方法来量化 A 和 B 抗原特异性 IgM、IgG 和 IgA，以提高准确性和重现性，并研究 ABO 组抗体类型与抗体水平之间的关系。

研究了来自 300 名健康献血者的血浆样本。通过凝集 (HA) 和多色流式细胞术 (MC-FC) 测量 IgM 和 IgG 与试剂组 A 和 B 红细胞的结合水平。IgA 也通过 MC-FC 测量。

发现我们的 FC 方法在测量血型 A 和 B 特异性抗体方面比 HA 具有更高的可重复性。我们发现 GC-HA 和 MC-FC 测量的抗体之间存在统计学上的显着相关性，但足够的差异表明这些方法并不等效。通过 MC-FC，发现 IgM、IgG 和 IgA 水平和同位素分布取决于供体 ABO 类型和抗体的特异性。

该研究证明了健康人群中 ABO 血型特异性抗体的免疫球蛋白类别谱的异质性。ABO 血型特异性抗体同种型谱的差异可能表明产生这些抗体的免疫机制存在根本差异。这可能与管理或诊断依赖于 ABO 特异性抗体检测和测量的临床情况有关。