Sundewall A C, Lefvert A K
Department of Medicine, Karolinska Hospital, Stockholm, Sweden.
Scand J Immunol. 1990 Apr;31(4):477-84. doi: 10.1111/j.1365-3083.1990.tb02795.x.
Auto-antibodies against the acetylcholine receptor of skeletal muscle are considered to be the cause of the neuromuscular dysfunction in myasthenia gravis. However, such auto-antibodies also occur in disease states not accompanied by neuromuscular symptoms. Patients with primary biliary cirrhosis have a high prevalence of different auto-antibodies, including antibodies against the acetylcholine receptor. In primary biliary cirrhosis, these anti-receptor antibodies are predominantly of IgM isotype. The IgM antibodies show a broader reactivity with receptors from other species than antibodies from myasthenic patients. Immunoglobulins from patients with primary biliary cirrhosis bear the same receptor antibody-associated idiotypes, but the repertoire is quantitatively different from that found in myasthenia gravis patients. The IgM receptor antibody activity in a serum from a patient with primary biliary cirrhosis could be inhibited by cardiolipin, poly[dT], poly[I], and ssDNA, whereas this antibody activity in serum from a patient with myasthenia gravis was slightly reduced only by cardiolipin. Generally, IgM antibodies from patients with primary biliary cirrhosis had a broader reactivity with polynucleotides and phospholipids than IgG antibodies and antibodies from patients with myasthenia gravis. These results indicate a difference in the fine specificity between acetylcholine receptor antibodies in primary biliary cirrhosis and in myasthenia gravis.
针对骨骼肌乙酰胆碱受体的自身抗体被认为是重症肌无力神经肌肉功能障碍的病因。然而，此类自身抗体也出现在未伴有神经肌肉症状的疾病状态中。原发性胆汁性肝硬化患者中存在多种自身抗体，包括针对乙酰胆碱受体的抗体，且患病率较高。在原发性胆汁性肝硬化中，这些抗受体抗体主要为IgM同种型。与重症肌无力患者的抗体相比，IgM抗体与其他物种的受体具有更广泛的反应性。原发性胆汁性肝硬化患者的免疫球蛋白具有相同的受体抗体相关独特型，但在数量上与重症肌无力患者不同。原发性胆汁性肝硬化患者血清中的IgM受体抗体活性可被心磷脂、聚[dT]、聚[I]和单链DNA抑制，而重症肌无力患者血清中的这种抗体活性仅被心磷脂轻微降低。一般来说，原发性胆汁性肝硬化患者的IgM抗体与多核苷酸和磷脂的反应性比IgG抗体以及重症肌无力患者的抗体更广泛。这些结果表明原发性胆汁性肝硬化和重症肌无力中乙酰胆碱受体抗体的精细特异性存在差异。
