Kondo T, Watarai Y, Novick A C, Toma H, Fairchild R L
Department of Urology, Cleveland Clinic Foundation, Ohio 44195, USA.
Transplantation. 1997 Mar 15;63(5):732-42. doi: 10.1097/00007890-199703150-00021.
Chemoattractant cytokines, chemokines, are likely to play a critical role in directing leukocytes to graft sites and in amplifying intragraft inflammation during rejection. Since second-set graft rejection occurs at an accelerated rate, we hypothesized that chemokine genes would be expressed earlier during secondary allograft rejection than during rejection of primary allografts. We have tested this hypothesis by using Northern blot analysis to compare intragraft expression levels of genes encoding interleukin (IL) 1beta and six chemokines during rejection of C57BL/6 skin grafts on naive and C57BL/6-sensitized BALB/c recipients. Expression levels of IL-1beta, interferon-gamma inducible protein, macrophage inflammatory protein-1 (MIP-1) alpha, and MIP-1beta genes were 10- to 17-fold higher on day 5 after transplantation in C57BL/6 grafts on C57BL/6-presensitized recipients than in C57BL/6 grafts on unprimed recipients. Intragraft expression of the chemokines regulated upon activation, normal T cell expressed and secreted (RANTES), during primary C57BL/6 graft rejection was virtually undetectable at day 7 after primary transplantation, but was expressed at high levels by day 5 after secondary transplantation. In third-party CBA/Ca allografts on unsensitized and C57BL/6-presensitized BALB/c mice, similar levels of IL-1beta, MIP-1alpha, and MIP-1beta expression were observed. High levels of RANTES and interferon-gamma inducible protein expression, however, were observed at day 5 after transplantation in CBA/Ca grafts on C57BL/6-presensitized recipients and correlated with accelerated rejection of the third-party grafts. Although T cells from C57BL/6-presensitized recipients did not express increased reactivity to CBA/Ca stimulator cells in vitro, serum antibodies from these recipients demonstrated reactivity to cells from CBA/Ca and A/J mice. When compared with transfer of unprimed cells, transfer of C57BL/6-primed lymphoid cells to sublethally irradiated BALB/c mice engrafted with C57BL/6 grafts resulted in increased intragraft proinflammatory cytokine gene expression. Deletion of T cells before transfer abrogated the increased intragraft expression of proinflammatory cytokine genes. Collectively, these results indicate that the accelerated expression of chemokine genes during second-set rejection of allogeneic skin grafts is mediated by immune T cells.
趋化性细胞因子，即趋化因子，可能在引导白细胞至移植部位以及在排斥反应期间放大移植内炎症方面发挥关键作用。由于二次移植排斥反应以加速的速率发生，我们推测趋化因子基因在二次同种异体移植排斥反应期间的表达会比在初次同种异体移植排斥反应期间更早出现。我们通过使用Northern印迹分析来比较编码白细胞介素（IL）-1β和六种趋化因子的基因在未致敏的和C57BL/6致敏的BALB/c受体接受C57BL/6皮肤移植排斥反应期间的移植内表达水平，对这一假设进行了验证。在移植后第5天，在C57BL/6预致敏受体接受的C57BL/6移植中，IL-1β、干扰素-γ诱导蛋白、巨噬细胞炎性蛋白-1（MIP-1）α和MIP-1β基因的表达水平比未致敏受体接受的C57BL/6移植中的表达水平高10至17倍。在初次C57BL/6移植排斥反应期间，在初次移植后第7天几乎检测不到趋化因子“活化调节的正常T细胞表达和分泌因子”（RANTES）的移植内表达，但在二次移植后第5天其表达水平很高。在未致敏的和C57BL/6预致敏的BALB/c小鼠接受的第三方CBA/Ca同种异体移植中，观察到IL-1β、MIP-1α和MIP-1β的表达水平相似。然而，在C57BL/6预致敏受体接受的CBA/Ca移植中，在移植后第5天观察到RANTES和干扰素-γ诱导蛋白的高水平表达，且与第三方移植的加速排斥相关。尽管来自C57BL/6预致敏受体的T细胞在体外对CBA/Ca刺激细胞没有表现出增加的反应性，但这些受体的血清抗体对来自CBA/Ca和A/J小鼠的细胞表现出反应性。与未致敏细胞的转移相比，将C57BL/6致敏的淋巴细胞转移至接受C57BL/6移植的经亚致死剂量照射的BALB/c小鼠，导致移植内促炎细胞因子基因表达增加。在转移前删除T细胞消除了移植内促炎细胞因子基因表达的增加。总体而言，这些结果表明同种异体皮肤移植二次排斥反应期间趋化因子基因的加速表达是由免疫T细胞介导的。
