de Laurentiis G, Vitiello L, Racioppi L, Perna F, Galgani M, Merola G, Carratù P, Maniscalco M, Marsico S, Sofia M
Dept of Respiratory Medicine, AO Monaldi, Second University of Naples, Naples, Italy.
Eur Respir J. 2007 Jul;30(1):165-71. doi: 10.1183/09031936.00145406.
Pulmonary alveolar microlithiasis (PAM) is a rare diffuse lung disease characterised by the accumulation of calcium phosphate microliths within the alveoli. The causative mechanism of PAM has only recently been discovered, and involves a gene mutation of sodium phosphate co-transporter, which is expressed by alveolar epithelial cells. This mutation may have variable consequences on the clinical phenotype. However, pulmonary cell immune phenotyping in familial PAM has not previously been assessed. In the present article, the analysis of bronchoalveolar lavage fluid of two siblings with PAM diagnosis revealed a pattern of lymphocytic alveolitis with accumulation of CD8+ T-cells. The clonal complexity of this lymphocyte's population was assayed by spectratyping, which showed an oligoclonal accumulation of T-cells with a restricted variable beta T-cell receptor (TCR) gene usage. TCR analysis in peripheral blood lymphocytes revealed no abnormal patterns of T-lymphocytes. In the pulmonary alveolar microlithiasis familial cases reported, CD8-mediated maladaptive immune response may have taken place in the bronchoalveolar compartment. The relationship between this immune dysregulation and genetic background in pulmonary alveolar microlithiasis warrants further investigation.
肺泡微石症（PAM）是一种罕见的弥漫性肺部疾病，其特征是肺泡内磷酸钙微结石的积聚。PAM的致病机制直到最近才被发现，涉及由肺泡上皮细胞表达的磷酸钠共转运蛋白的基因突变。这种突变可能对临床表型产生不同的影响。然而，此前尚未对家族性PAM中的肺细胞免疫表型进行评估。在本文中，对两名被诊断为PAM的兄弟姐妹的支气管肺泡灌洗液进行分析，发现了一种伴有CD8 + T细胞积聚的淋巴细胞性肺泡炎模式。通过光谱分型法检测了该淋巴细胞群体的克隆复杂性，结果显示T细胞呈寡克隆积聚，其可变β T细胞受体（TCR）基因使用受限。外周血淋巴细胞的TCR分析未发现T淋巴细胞有异常模式。在已报道的肺泡微石症家族病例中，CD8介导的适应性免疫反应可能在支气管肺泡腔中发生。这种免疫失调与肺泡微石症遗传背景之间的关系值得进一步研究。
