Fazel S B, Howie S E, Krajewski A S, Lamb D
Department of Pathology, University of Edinburgh Medical School.
Thorax. 1992 Nov;47(11):964-7. doi: 10.1136/thx.47.11.964.
Although cell mediated immunity is primarily thought to mediate the pathogenesis of sarcoidosis, the presence of immunoglobulins, immune complexes and complement suggests that processes of humoral immunity may contribute to immunopathology in sarcoid lesions. To test this hypothesis, the distribution of B lymphocytes in paraffin embedded sarcoid lesions in mediastinal lymph nodes and open lung biopsy specimens was investigated.
Paraffin sections from eight open lung and 21 lymph node biopsies from sarcoid patients and five normal and five tuberculous lymph nodes from patients with tuberculosis were stained with a panel of monoclonal antibodies by means of avidin/biotin enhanced immunocytochemistry.
Immunohistochemical analysis of the 29 biopsy specimens from the sarcoid patients revealed large numbers of B cells in the intergranulomatous regions. Further investigations in the open lung biopsy specimens indicated that these B cells were often organised into discrete circular or oval shaped aggregates with no germinal centre morphology, in which a few CD45RO memory T lymphocytes were scattered. The B cells were polyclonal, and a few plasma cells (IgM+, IgA+, IgG+) were identified.
The finding of large numbers of B lymphocytes in sarcoid pulmonary lesions is in contrast to bronchoalveolar lavage studies, which have demonstrated proportions of 5% or less of B cells as a total of all immune cells, and therefore indicates that bronchoalveolar lavage may not correctly sample the immune cells of lung interstitial tissue in pulmonary sarcoidosis. The B cells at these sites are the possible origin of some of the humoral changes in the serum and lesions of sarcoid patients. They may also influence the pathogenesis of the disorder by presenting antigen(s) and forming immune complexes at sites of disease activity.
虽然细胞介导的免疫主要被认为介导结节病的发病机制，但免疫球蛋白、免疫复合物和补体的存在表明体液免疫过程可能参与结节病病变的免疫病理过程。为了验证这一假设，研究了石蜡包埋的纵隔淋巴结和开胸肺活检标本中结节病病变内B淋巴细胞的分布。
采用抗生物素蛋白/生物素增强免疫细胞化学方法，用一组单克隆抗体对8例结节病患者的开胸肺活检标本和21例淋巴结活检标本以及5例结核病患者的正常淋巴结和5例结核性淋巴结的石蜡切片进行染色。
对29例结节病患者的活检标本进行免疫组织化学分析发现，肉芽肿间区域有大量B细胞。对开胸肺活检标本的进一步研究表明，这些B细胞常组织成离散的圆形或椭圆形聚集物，无生发中心形态，其中散在少量CD45RO记忆性T淋巴细胞。B细胞为多克隆性，还鉴定出少量浆细胞（IgM+、IgA+、IgG+）。
结节病肺部病变中发现大量B淋巴细胞，这与支气管肺泡灌洗研究结果相反，后者显示B细胞占所有免疫细胞总数的比例为5%或更低，因此表明支气管肺泡灌洗可能无法正确采集肺结节病患者肺间质组织的免疫细胞样本。这些部位的B细胞可能是结节病患者血清和病变中一些体液变化的来源。它们还可能通过在疾病活动部位呈递抗原和形成免疫复合物来影响该疾病的发病机制。
