Rheumatology Unit, University Hospital, SE-581 85 Linköping, Sweden.
J Rheumatol. 2011 Feb;38(2):215-20. doi: 10.3899/jrheum.100690. Epub 2010 Nov 1.
To evaluate (1) to what extent sera from healthy subjects and patients with rheumatoid arthritis (RA) contain antibodies to bovine serum albumin (BSA); and (2) if anti-BSA antibodies interfere with results of enzyme-linked immunoassays (ELISA) containing BSA.
The ELISA used was a previously developed in-house assay of autoantibodies to tumor necrosis factor (TNF). Anti-TNF and anti-BSA antibodies were analyzed by ELISA in 189 patients with early RA and 186 healthy blood donors. TNF preparations containing either BSA or human serum albumin (HSA) as carrier proteins were used as antigens in the anti-TNF assay. The presence and levels of antibodies were analyzed in relation to disease course and to the presence/absence of rheumatoid factor (RF).
In patients with RA, anti-TNF/BSA levels strongly correlated with anti-BSA levels (r = 0.81, p < 0.001), whereas anti-TNF/HSA did not (r = -0.09). Neither the presence nor the levels of anti-BSA in RA patients were associated with disease progression, and antibody levels were not significantly altered compared to controls (p = 0.11). IgG reactivity with TNF/HSA was neglible. In paired sera, preincubation with BSA abolished the anti-TNF/BSA reactivity. There were no indications of RF interference with anti-BSA or anti-TNF reactivity.
Antibodies to BSA are common in patients with RA as well as in healthy individuals. Their presence does not seem to be associated with RA disease activity or disease course, but may severely interfere with ELISA containing BSA. The use of BSA as a "blocking agent" or carrier protein in immunoassays should therefore be avoided.
评估（1）健康受试者和类风湿关节炎（RA）患者血清中含有针对牛血清白蛋白（BSA）的抗体的程度；以及（2）抗 BSA 抗体是否会干扰含有 BSA 的酶联免疫吸附测定（ELISA）的结果。
使用的 ELISA 是之前开发的用于检测肿瘤坏死因子（TNF）自身抗体的内部检测方法。在 189 例早期 RA 患者和 186 名健康献血者中，通过 ELISA 分析抗 TNF 和抗 BSA 抗体。将含有 BSA 或人血清白蛋白（HSA）作为载体蛋白的 TNF 制剂用作抗 TNF 检测中的抗原。分析了抗体的存在和水平与疾病进程以及类风湿因子（RF）的存在/缺失的关系。
在 RA 患者中，抗 TNF/BSA 水平与抗 BSA 水平强烈相关（r = 0.81，p <0.001），而抗 TNF/HSA 则不相关（r = -0.09）。RA 患者中抗 BSA 的存在或水平与疾病进展无关，与对照组相比，抗体水平没有明显变化（p = 0.11）。IgG 对 TNF/HSA 的反应性可以忽略不计。在配对血清中，用 BSA 预孵育可消除抗 TNF/BSA 反应性。没有迹象表明 RF 会干扰抗 BSA 或抗 TNF 反应性。
BSA 抗体在 RA 患者和健康个体中都很常见。它们的存在似乎与 RA 疾病活动或疾病进程无关，但可能会严重干扰含有 BSA 的 ELISA。因此，在免疫测定中应避免将 BSA 用作“阻断剂”或载体蛋白。
