Division of Transfusion Medicine, Department of Pathology & Laboratory Medicine, Ronald Reagan UCLA Medical Center, Los Angeles, California, USA.
Transfusion. 2010 May;50(5):1139-43. doi: 10.1111/j.1537-2995.2009.02545.x. Epub 2009 Dec 29.
Rabbit erythrocyte stroma (RESt, Immucor) adsorption is often used to remove cold autoantibodies from patient samples to facilitate detection of underlying alloantibodies. However, reports in the literature show that adsorption of clinically significant alloantibodies can occur. A 2006 study by Storry and colleagues suggested that immunoglobulin (Ig)M antibodies are adsorbed by RESt regardless of antigen specificity. In our study, we further investigated the adsorption of IgM red blood cell alloantibodies by RESt.
A total of 12 sera containing monoclonal IgM antibodies of various specificities (anti- D, -C, -c, -E, -e, -K, -Jk(b), and -S) and titers, which were all shown to exhibit only IgM reactivity after dithiothreitol treatment, and two sera with polyclonal IgG (anti-Fy(a) and -K) were all adsorbed by RESt. Titers of unadsorbed, once-adsorbed, and twice-adsorbed IgM and IgG antibodies were determined in parallel.
Ten of the 12 monoclonal IgM samples showed significant (more than fourfold) reduction in titer after RESt adsorptions. Both of the polyclonal IgG samples tested showed insignificant (fourfold or less) reduction in titer.
RESt is known to effectively remove IgM cold autoantibodies. Our results show that monoclonal IgM alloantibodies are also frequently adsorbed by RESt with significant reduction in titer. Adsorption is variable and some IgM alloantibodies are not adsorbed. Further studies may elucidate the effect of RESt adsorption on IgG alloantibodies. Caution is needed when RESt is employed to remove interferences by cold autoantibodies in pretransfusion testing, and the risk of missed IgM alloantibodies must be considered.
兔红细胞基质（RESt，Immucor）吸附常用于从患者样本中去除冷自身抗体，以促进对潜在同种异体抗体的检测。然而，文献中的报道表明，临床意义上的同种异体抗体也可能被吸附。2006 年，Storry 及其同事的一项研究表明，无论抗原特异性如何，IgM 抗体都会被 RESt 吸附。在我们的研究中，我们进一步研究了 RESt 对 IgM 红细胞同种异体抗体的吸附。
共有 12 份血清，其中含有各种特异性（抗-D、-C、-c、-E、-e、-K、-Jk(b)和-S）和滴度的单克隆 IgM 抗体，这些抗体在二硫苏糖醇处理后均显示仅为 IgM 反应性，还有两份含多克隆 IgG（抗-Fy(a)和-K）的血清也被 RESt 吸附。平行测定未吸附、一次吸附和两次吸附的 IgM 和 IgG 抗体的滴度。
12 份单克隆 IgM 样本中的 10 份在 RESt 吸附后显示出明显（四倍以上）的滴度降低。测试的两份多克隆 IgG 样本的滴度降低不明显（四倍或以下）。
RESt 已知能有效去除 IgM 冷自身抗体。我们的结果表明，同种异体 IgM 抗体也经常被 RESt 吸附，导致滴度显著降低。吸附是可变的，有些 IgM 同种异体抗体不会被吸附。进一步的研究可能阐明 RESt 吸附对 IgG 同种异体抗体的影响。在输血前检测中使用 RESt 去除冷自身抗体的干扰时需要谨慎，必须考虑到可能会漏检 IgM 同种异体抗体的风险。
