Hasegawa T, Iacono A, Yousem S A
Department of Pathology, University of Pittsburgh Medical Center-Presbyterian University Hospital, Pennsylvania 15213, USA.
Transplantation. 1999 Feb 15;67(3):381-5. doi: 10.1097/00007890-199902150-00007.
In animal models of acute rejection in lung allografts, bronchus-associated lymphoid tissue (BALT) plays a major role in the induction and persistence of the alloreactive response. We undertook a study of the clinical and histologic associations with BALT identified on transbronchial biopsy in human lung allograft recipients.
Transbronchial biopsies of patients receiving single lung, double lung, and combined heart-lung transplantation from 1984 to 1997 at the University of Pittsburgh Medical Center were reviewed. Seventy-seven patients had transbronchial biopsies demonstrating BALT. We examined all pathologic reports and slides, and graded rejection utilizing the Revised Working Formulation for the Classification of Pulmonary Allograft Rejection. Twenty-nine of 77 patients were selected at random to evaluate the distribution of BALT lymphocyte subsets immunohistochemically.
There was no relationship between native disease or the transplant procedure and the identification of BALT. BALT was found from 9 days to 2431 days after transplant (average: 440 days; median: 157 days) in association with clinically insignificant acute cellular rejection (A0, A1) in 75% of cases. Bronchiolitis obliterans developed in 29% of patients with a BALT-positive biopsy, a percentage not different from that of our overall lung transplant population. Immunohistochemical examination of BALT showed helper T cells predominated over cytotoxic T cells in zones surrounding B cell-rich follicular center cells.
The association of BALT with high-grade acute cellular rejection and with the development of bronchiolitis obliterans could not be confirmed in human lung allografts. BALT most often accompanied A0 or A1 rejection. This raises the possibility that the presence of BALT on transbronchial biopsy may be part of the evolution of immunologic tolerance in human pulmonary allografts.
在肺同种异体移植急性排斥反应的动物模型中，支气管相关淋巴组织（BALT）在同种异体反应的诱导和持续中起主要作用。我们对人类肺同种异体移植受者经支气管活检中识别出的BALT进行了临床和组织学相关性研究。
回顾了1984年至1997年在匹兹堡大学医学中心接受单肺、双肺及心肺联合移植患者的经支气管活检情况。77例患者经支气管活检显示有BALT。我们检查了所有病理报告和切片，并根据肺同种异体移植排斥反应分类的修订工作方案对排斥反应进行分级。从77例患者中随机选取29例，通过免疫组织化学方法评估BALT淋巴细胞亚群的分布。
原发疾病或移植手术与BALT的识别之间无相关性。移植后9天至2431天（平均：440天；中位数：157天）发现BALT，75%的病例与临床意义不显著的急性细胞排斥反应（A0、A1）相关。29%的BALT活检阳性患者发生了闭塞性细支气管炎，这一比例与我们整个肺移植人群的比例无差异。对BALT的免疫组织化学检查显示，在富含B细胞的滤泡中心细胞周围区域，辅助性T细胞多于细胞毒性T细胞。
在人类肺同种异体移植中，无法证实BALT与重度急性细胞排斥反应及闭塞性细支气管炎的发生有关。BALT最常伴随A0或A1排斥反应。这增加了经支气管活检中BALT的存在可能是人类肺同种异体移植免疫耐受演变一部分的可能性。
