背景:先前已经描述了次级淋巴器官中的正常胸腺细胞前体。重要的是通过流式细胞术识别正常胸腺细胞前体,以区分它们与T细胞淋巴细胞白血病。
方法:一名3岁男孩在同种异体心脏移植2年后接受了腺样体切除术以排除移植后淋巴增生性疾病。微观,免疫组织化学,进行腺样体的流式细胞术分析。
结果:通过流式细胞术,在1.0%的淋巴细胞中观察到CD45(dim)/CD7(bright)/CD3-细胞群。这些细胞表达CD10,部分CD34,并显示获得CD4,然后获得CD8。在更亮的CD45+淋巴细胞中,鉴定了CD3-/CD4+/CD8+胸腺细胞群和类似大小的CD4+/CD8+细胞群,其表现出获得低密度CD3.通过免疫染色,在卵泡间区域发现了TdT+/CD1a+/CD4+/CD8+T细胞簇.与正常胸腺相比,腺样体组织中的胸腺细胞缺乏经典的CD4xCD8翼状分化曲线,但显示出正常的早期前体模式。
结论:腺样体胸腺细胞与胸腺和胸腺瘤有相似的分化模式。然而,在胸腺外分化的胸腺细胞中,常见的胸腺细胞分化的典型翼状模式可能并不明显。早期胸腺细胞前体抗原获取谱的识别对于正确解释可能是至关重要的。©2017国际临床细胞计数学会。
BACKGROUND: Normal thymocyte precursors in secondary lymphoid organs have previously been described. It is important to recognize normal thymocyte precursors by flow cytometry to differentiate them from T-cell lymphoblastic leukemia.
METHODS: A 3-year-old boy status 2 years post-allogenic cardiac transplant underwent adenoidectomy to exclude post-transplant lymphoproliferative disorder. Microscopic, immunohistochemical, and flow cytometry analyses of the
adenoid were performed.
RESULTS: By flow cytometry, a population of CD45+(dim)/CD7+(bright)/CD3- cells were observed at 1.0% of lymphocytes. These cells expressed CD10, partial CD34, and exhibited acquisition of CD4 followed by CD8. Within the brighter CD45+ lymphocytes, a population of CD3-/CD4+/CD8+ thymocytes and a similarly sized population of CD4+/CD8+ cells exhibiting acquisition of low-density CD3 were identified. By immunostaining, clusters of TdT+/CD1a+/CD4+/CD8+ T-cells were identified in the interfollicular areas. Compared to normal thymus, thymocytes in the
adenoid tissue lacked the classic CD4xCD8 winged differentiation profile but showed a normal early precursor pattern.
CONCLUSIONS: Thymocytes in
adenoid show a similar differentiation pattern to thymus and thymoma. However, the classic winged pattern of common thymocyte differentiation may not be readily apparent in thymocytes differentiating outside of the thymus. Recognition of the early thymocyte precursor antigen acquisition profile can be crucial to correct interpretation. © 2017 International Clinical Cytometry Society.