Van Kerckhove C W, Ceuppens J L, Vanderschueren-Lodeweyckx M, Eggermont E, Vertessen S, Stevens E A
Department of Pediatrics, Faculty of Medicine, University of Leuven, Belgium.
Am J Dis Child. 1988 Oct;142(10):1089-93. doi: 10.1001/archpedi.1988.02150100083032.
Immune function was studied in four patients (two girls and two boys, aged 30 months to 24 years) with documented Bloom's syndrome. Three patients had a decreased serum concentration of at least one subclass of immunoglobulins. All had normal or elevated proportions of circulating B cells but two of them had a decreased proportion of CD4-positive helper-inducer T cells. We consistently found a severely impaired in vitro proliferative lymphocyte response to the plant lectin pokeweed mitogen (PWM). This could not be overcome by using suboptimal or supraoptimal doses of PWM, or by adding recombinant interleukin 2. In vitro PWM-induced IgM production was absent or low in two of the three patients studied and this low production could not be increased by addition of hydrocortisone. T lymphocytes responded normally to the plant lectins phytohemagglutinin and concanavalin A. T cells preactivated with phytohemagglutinin also normally proliferated in response to interleukin 2. It has previously been shown that lymphocyte activation with PWM involves both B and T cells and proceeds via an alternative pathway. The data thus indicate that patients with Bloom's syndrome have a specific defect in this PWM-induced alternative pathway of lymphocyte activation.
对4例确诊为布卢姆综合征的患者（2名女孩和2名男孩，年龄30个月至24岁）的免疫功能进行了研究。3例患者至少有一种免疫球蛋白亚类的血清浓度降低。所有患者循环B细胞比例正常或升高，但其中2例CD4阳性辅助诱导性T细胞比例降低。我们始终发现，患者对植物凝集素商陆有丝分裂原（PWM）的体外增殖性淋巴细胞反应严重受损。使用次优或超优剂量的PWM，或添加重组白细胞介素2，均无法克服这一问题。在研究的3例患者中，有2例体外PWM诱导的IgM产生缺失或很低，添加氢化可的松也无法增加这种低产量。T淋巴细胞对植物凝集素植物血凝素和刀豆球蛋白A反应正常。用植物血凝素预激活的T细胞对白细胞介素2也能正常增殖。此前已有研究表明，PWM激活淋巴细胞涉及B细胞和T细胞，并通过替代途径进行。因此，数据表明，布卢姆综合征患者在这种PWM诱导的淋巴细胞激活替代途径中存在特定缺陷。
