Bird P, Calvert J E, Mitchison H, Ling N R, Bassendine M, James O F
Department of Pathology, University of Newcastle-upon-Tyne, UK.
Clin Exp Immunol. 1988 Mar;71(3):475-80.
The origin of the raised serum IgG3 in primary biliary cirrhosis has been examined. Blood lymphocytes from patients with PBC and from age- and sex-matched controls were cultured, and the culture supernatants were assayed for IgG and IgG3. Lymphocytes from PBC patients spontaneously synthesized a higher percentage IgG3/total IgG than did control lymphocytes, as determined by ELISA. The increased synthesis of IgG3 in culture correlated with serum IgG3 in the patients. This strongly suggests that the raised serum IgG3 in these patients is due to increased synthesis of this isotype. Following PWM stimulation, the proportion of IgG3/IgG synthesized by normal (and most PBC) lymphocytes increased and the difference in IgG3 synthesized by PBC and control lymphocytes became less marked. The kappa/lambda light chain ratio of the IgG3 was assayed by ELISA but no evidence was found for clonally restricted synthesis of IgG3 by PBC blood lymphocytes.
对原发性胆汁性肝硬化患者血清IgG3升高的原因进行了研究。对原发性胆汁性肝硬化患者以及年龄和性别匹配的对照者的血液淋巴细胞进行培养，并对培养上清液中的IgG和IgG3进行检测。通过酶联免疫吸附测定法（ELISA）测定，原发性胆汁性肝硬化患者的淋巴细胞自发合成的IgG3占总IgG的百分比高于对照淋巴细胞。培养物中IgG3合成的增加与患者血清IgG3相关。这有力地表明，这些患者血清IgG3升高是由于该同种型合成增加所致。在经美洲商陆有丝分裂原（PWM）刺激后，正常（以及大多数原发性胆汁性肝硬化患者）淋巴细胞合成的IgG3/IgG比例增加，原发性胆汁性肝硬化患者和对照淋巴细胞合成的IgG3差异变得不那么明显。通过ELISA检测IgG3的κ/λ轻链比例，但未发现原发性胆汁性肝硬化患者血液淋巴细胞克隆性受限合成IgG3的证据。
