Córsico B, Croce M V, Mukherjee R, Segal-Eiras A
Centro de Investigaciones Immunológicas Básicas y Aplicadas (CINIBA), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, Argentina.
Clin Immunol Immunopathol. 1994 Apr;71(1):38-43. doi: 10.1006/clin.1994.1049.
Circulating immune complexes (CIC) were first measured in lepromatous patients (LL) by the 125I-C1q binding assay and the polyethylene glycol (PEG) precipitation test. High levels were found by both methods (95 and 90% of positives, respectively). LL-CIC were investigated for the presence of neural antigens. CIC were precipitated in 3.5% PEG, filtered through protein A-Sepharose affinity chromatography, eluted with glycine-HCl, pH 2.8, and washed with PBS; fractions after CIC dissociation were studied by SDS-PAGE and Western blotting. The LL-CIC PEG precipitates and the glycine-HCl eluates were positive in 76 and 71% respectively against anti-myelin basic proteins (MBP) monoclonal antibody, showing a single band at 15-25 kDa similar to the one obtained incubating MBP with anti-MBP. No reaction was detected with CIC-PBS fractions; strips were incubated with other anti-neural antibodies such as anti-glial fibrillary acidic proteins, anti-S-100, and anti-neurofilaments, without any reactivity. Our results demonstrate that LL-CIC contain MBP as an antigen; its significance could be related to the pathogenesis of leprosy since the liberation of MBP after Mycobacterium leprae nerve damage may elicit anti-MBP autoantibodies to myelin breakdown, which reacts with peripheral nerve MBP inducing CIC formation. This mechanism may be important in demyelination and destruction of nerve in leprosy.
循环免疫复合物（CIC）最初是通过125I-C1q结合试验和聚乙二醇（PEG）沉淀试验在瘤型麻风患者（LL）中检测到的。两种方法均检测到高水平的CIC（分别为95%和90%呈阳性）。对LL-CIC进行了神经抗原检测。将CIC在3.5%PEG中沉淀，通过蛋白A-琼脂糖亲和层析过滤，用pH 2.8的甘氨酸-HCl洗脱，并用磷酸盐缓冲盐水（PBS）洗涤；CIC解离后的组分通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和蛋白质印迹法进行研究。LL-CIC PEG沉淀物和甘氨酸-HCl洗脱物分别有76%和71%对抗髓磷脂碱性蛋白（MBP）单克隆抗体呈阳性，在15 - 25 kDa处显示出一条与MBP与抗MBP孵育所得条带相似的单条带。未检测到CIC-PBS组分有反应；将条带与其他抗神经抗体如抗胶质纤维酸性蛋白、抗S-100和抗神经丝蛋白一起孵育，未发现任何反应性。我们的结果表明LL-CIC含有MBP作为一种抗原；其意义可能与麻风病的发病机制有关，因为麻风杆菌神经损伤后MBP的释放可能引发针对髓磷脂分解的抗MBP自身抗体，该抗体与周围神经MBP反应诱导CIC形成。这种机制可能在麻风病的脱髓鞘和神经破坏中起重要作用。
