Lewis S L, Kutvirt S G, Seamer L C, Holmes C J
Department of Pathology, School of Medicine, University of New Mexico, Albuquerque 87131, USA.
Perit Dial Int. 1997 May-Jun;17(3):287-94.
Cellular immune function in peritoneal dialysis patients has been shown to be depressed, but the mechanism of this immunosuppression has not been ascertained. Because calcium is an important mediator of lymphocyte activation, this study was designed to investigate if there was an alteration of calcium metabolism in the lymphocytes of continuous ambulatory peritoneal dialysis (CAPD) patients.
Sixteen CAPD patients were studied at the initiation of CAPD and after two months of treatment. Twenty-three normal controls were also enrolled in the study. Cytoplasmic calcium changes were investigated in response to the mitogen phytohemagglutinin (PHA) in peripheral blood and peritoneal lymphocytes, using the intracellular calcium probe indo-1 and flow cytometry. Baseline cytoplasmic calcium levels and changes in cytoplasmic calcium in response to PHA were assessed at the initiation of CAPD and after two months of therapy.
Peripheral lymphocytes of patients and controls had similar calcium baseline levels, but the peritoneal lymphocytes had baseline cytoplasmic calcium levels averaging 81% higher than the corresponding calcium levels of the patients' peripheral blood lymphocytes. As compared to peripheral lymphocytes, the response to PHA stimulation was significantly less in the peritoneal lymphocytes, increasing an average of only 46.8% above baseline. Peripheral blood lymphocytes of the patients responded by an average increase of 78.9% over baseline. Control cells increased an average of 66.3% over baseline. Follow-up studies done two months after the initiation of CAPD indicated there were no significant changes (as compared to month 0) that occurred in baseline or stimulated intracellular calcium concentrations.
While the peripheral lymphocytes of CAPD patients respond adequately to PHA, the high baseline calcium levels of the peritoneal lymphocytes suggest that these cells may be in a state of chronic activation and may respond minimally to an antigenic challenge.
已有研究表明腹膜透析患者的细胞免疫功能受到抑制，但其免疫抑制机制尚未明确。由于钙是淋巴细胞激活的重要介质，本研究旨在调查持续性非卧床腹膜透析（CAPD）患者淋巴细胞中的钙代谢是否存在改变。
对16例CAPD患者在开始CAPD治疗时及治疗两个月后进行研究。还纳入了23名正常对照者参与该研究。使用细胞内钙探针indo-1和流式细胞术，研究外周血和腹膜淋巴细胞对丝裂原植物血凝素（PHA）刺激的细胞质钙变化。在开始CAPD治疗时及治疗两个月后，评估细胞质钙基线水平以及对PHA刺激的细胞质钙变化。
患者和对照者的外周淋巴细胞具有相似的钙基线水平，但腹膜淋巴细胞的细胞质钙基线水平平均比患者外周血淋巴细胞的相应钙水平高81%。与外周淋巴细胞相比，腹膜淋巴细胞对PHA刺激的反应明显较弱，平均仅比基线水平增加46.8%。患者的外周血淋巴细胞平均比基线水平增加78.9%。对照细胞平均比基线水平增加66.3%。CAPD治疗开始两个月后的随访研究表明，基线或刺激后的细胞内钙浓度没有显著变化（与第0个月相比）。
虽然CAPD患者的外周淋巴细胞对PHA有充分反应，但腹膜淋巴细胞的高基线钙水平表明这些细胞可能处于慢性激活状态，对抗原刺激的反应可能最小。
