Chevrier D, Giral M, Braud V, Bourbigot B, Muller J Y, Bignon J D, Soulillou J P
Centre Regional de Transfusion Sanguine BP349, Nantes, France.
Transplantation. 1995 Aug 15;60(3):292-6. doi: 10.1097/00007890-199508000-00015.
The products of TAP1 and TAP2 genes, recently mapped within the MHC class II region, are involved in antigen presentation by MHC class I molecules, especially in the transport of endogenous peptides. As for most MHC genes, a polymorphism has been described and the possibility that it could influence the recipient immune response by modulating antigen presentation in kidney transplantation has been tested. The aim of our study was to compare TAP1 and TAP2 gene polymorphism and matching in 53 couples of kidney donors and recipients without any rejection episodes and in 55 other couples who had experienced at least 2 acute cellular rejection episodes; 70 healthy individuals served as controls. Our results showed that allelic variant frequencies of TAP1 alleles (1A to 1C) and TAP2 alleles (2A to 2E), as assessed by amplification refractory mutation system-polymerase chain reaction, were similar among "rejection" and "no rejection" populations. Furthermore, there were no differences of TAP1 and/or TAP2 matching between donors and recipients in the 2 groups. In contrast, we showed that the recipients of the no rejection group were better matched with their corresponding donors for the HLA-DR genes than those of the rejection group. These results suggest that the currently described polymorphism in the limited coding region of TAP1 and TAP2 genes does not influence the incidence of kidney allograft rejection episodes and seems not to be a strong link to the adjacent DR/DQ subregion. Moreover, the observed increase frequency of TAP1B allele in the whole recipient's group as compared with controls (16.2% vs. 7.1% in the healthy individuals; P < 0.02) was not linked to the rejection occurrence but to the presence of glomerulonephritis as initial disease. Our study suggests that, in the clinical conditions tested, neither TAP polymorphism nor TAP matching influences the renal graft outcome.
TAP1和TAP2基因的产物最近被定位在MHC II类区域内，它们参与MHC I类分子的抗原呈递，特别是在内源性肽的转运过程中。与大多数MHC基因一样，已经描述了其多态性，并且已经测试了其通过调节肾移植中的抗原呈递来影响受体免疫反应的可能性。我们研究的目的是比较53对没有任何排斥反应的肾供体和受体以及55对经历过至少2次急性细胞排斥反应的其他供受体对中TAP1和TAP2基因的多态性及匹配情况；70名健康个体作为对照。我们的结果表明，通过扩增阻滞突变系统-聚合酶链反应评估，“排斥”和“无排斥”人群中TAP1等位基因（1A至1C）和TAP2等位基因（2A至2E）的等位基因变体频率相似。此外，两组供体和受体之间TAP1和/或TAP2的匹配没有差异。相比之下，我们发现无排斥组的受体与相应供体在HLA-DR基因上的匹配比排斥组更好。这些结果表明，目前所描述的TAP1和TAP2基因有限编码区域的多态性不会影响肾移植排斥反应的发生率，似乎也与相邻的DR/DQ亚区域没有紧密联系。此外，与对照组相比，整个受体组中观察到的TAP1B等位基因频率增加（健康个体中为7.1%，而受体组中为16.2%；P<0.02）与排斥反应的发生无关，而是与初始疾病为肾小球肾炎有关。我们的研究表明，在所测试的临床条件下，TAP多态性和TAP匹配均不影响肾移植结果。
