Maternal microchimerism in biliary atresia.

本研究的目的是确定母体微嵌合在胆道闭锁（BA）患者肝脏中的存在和程度。根据受试者的性别进行了两个系列的调查。系列1的受试者为男性。6人有BA。用X和Y染色体探针和荧光原位杂交（FISH）分析肝脏。第二组的受试者为女性。9例BA患者及其母亲均为HLA型（I型）。对女儿的肝脏也进行了母体和其他HLA抗体的检测。以新生儿肝炎2例、Alagille综合征2例、Byler综合征1例为对照。所有男性BA肝脏都含有含有一条和两条X染色体（即XY或XX）的细胞混合物。所有男性对照组的肝脏都只有一条X染色体（即XY）。所有BA女性受试者的胆管上皮和肝细胞中均存在不同强度的抗母体hla - I （HLA-A）抗体（5例强，3例弱，1例弱）。女性对照组的肝脏未显示任何抗母体hla - I类抗体（HLA-Ab）。我们的初步数据似乎表明母体微嵌合存在于进行性产后型BA患者的肝脏中。我们认为，BA实际上可能是一种移植物抗宿主病，伪装成母体微嵌合引发的自身免疫反应，我们将进一步研究这一假设，以澄清BA的病因。

The aim of this study was to determine the existence and extent of maternal microchimerism in the livers of biliary atresia (BA) patients.Two series of investigations were performed based on the sex of our subjects.Subjects for series I were male. Six had BA. Livers were analyzed using X and Y chromosome probes and fluorescent in situ hybridization (FISH).Subjects for series II were female. Nine BA cases and their mothers were HLA typed (class I). Daughter livers were also tested for antibodies to maternal and other HLA.Two cases of neonatal hepatitis, 2 cases of Alagille syndrome, and 1 case of Byler's syndrome acted as controls.All male BA livers were found to contain a mixture of cells with one and two X chromosomes (i.e., XY or XX). All livers from male controls had only one X chromosome (i.e., XY). All female BA subjects had varying intensities of anti-maternal HLA-class I (HLA-A) antibodies in their bile duct epithelium and hepatocytes (strong in 5, mild in 3 and weak in 1). The liver from the female control did not display any anti-maternal HLA-class I antibodies (HLA-Ab).Our preliminary data appear to show that maternal microchimerism is present within the livers of patients with progressive postnatal type BA. We suggest that BA could in fact be a graft versus host disease masquerading as an autoimmune reaction triggered by maternal microchimerism and we will pursue this hypothesis further to clarify the etiology of BA.