Davies Christopher J, Eldridge Jennifer A, Fisher Patricia J, Schlafer Donald H
Department of Veterinary Microbiology and Pathology & Center for Reproductive Biology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA.
Am J Reprod Immunol. 2006 Mar;55(3):188-200. doi: 10.1111/j.1600-0897.2005.00364.x.
During the third trimester of pregnancy bovine trophoblast cells in the interplacentomal and arcade regions of the placenta express major histocompatibility complex class I (MHC-I) antigens. At parturition immunological recognition of MHC-I antigens appears to contribute to normal placental release. Therefore, we hypothesized that during late pregnancy bovine trophoblast cells express polymorphic, classical MHC-I antigens.
Cloning, microarray screening and sequencing of cDNA were used to study transcription of MHC-I genes in peripheral blood mononuclear cells (PBMC) and interplacentomal, trophoblast cells. Real-time reverse transcription, polymerase chain reaction (RT-PCR) was used to compare the abundance of MHC-I transcripts in PBMC and trophoblast cells.
Screening of cloned MHC-I cDNA on MHC-I microarrays indicated that in PBMC 90-98% of MHC-I transcripts were encoded by classical MHC-I genes with the remainder encoded by non-classical MHC-I genes. In contrast, 21-66% of MHC-I transcripts from interplacentomal trophoblast cells were from classical genes and 34-79% were from non-classical genes. Transcripts from four non-classical MHC-I loci were identified by sequence analysis. Real-time RT-PCR indicated that the overall levels of MHC-I gene expression in PBMC and trophoblast were similar.
Bovine interplacentomal trophoblast cells express both classical and non-classical MHC-I genes, but the relative level of expression varies considerably.
在妊娠晚期，胎盘中间隔区和绒毛叶区的牛滋养层细胞表达主要组织相容性复合体I类（MHC-I）抗原。分娩时，对MHC-I抗原的免疫识别似乎有助于胎盘正常娩出。因此，我们推测在妊娠后期牛滋养层细胞表达多态性的经典MHC-I抗原。
采用克隆、微阵列筛选和cDNA测序来研究外周血单个核细胞（PBMC）以及胎盘中间隔区滋养层细胞中MHC-I基因的转录情况。运用实时逆转录聚合酶链反应（RT-PCR）比较PBMC和滋养层细胞中MHC-I转录本的丰度。
在MHC-I微阵列上对克隆的MHC-I cDNA进行筛选表明，在PBMC中，90%-98%的MHC-I转录本由经典MHC-I基因编码，其余由非经典MHC-I基因编码。相比之下，胎盘中间隔区滋养层细胞中21%-66%的MHC-I转录本来自经典基因，34%-79%来自非经典基因。通过序列分析鉴定出了来自四个非经典MHC-I基因座的转录本。实时RT-PCR表明，PBMC和滋养层细胞中MHC-I基因的总体表达水平相似。
牛胎盘中间隔区滋养层细胞同时表达经典和非经典MHC-I基因，但表达的相对水平差异很大。
