Toyama Chiyoshi, Maeda Akira, Kogata Shuhei, Yamamoto Riho, Masahata Kazunori, Ueno Takehisa, Kamiyama Masafumi, Tazuke Yuko, Eguchi Hiroshi, Okuyama Hiroomi, Miyagawa Shuji
Department of Pediatric Surgery, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan.
International Institute for Bio-Resource Research, Meiji University, Kawasaki, Kanagawa 214-8571, Japan.
Exp Ther Med. 2022 Jul 26;24(3):590. doi: 10.3892/etm.2022.11527. eCollection 2022 Sep.
Macrophage-mediated xenogeneic rejection is a major immunological obstacle. We recently reported that membrane-type surfactant protein-D (SP-D) on swine endothelial cells (SECs) suppressed macrophage-mediated rejection. Similar to SP-D, the carbohydrate recognition domain of surfactant protein-A (SP-A) can induce inhibitory signals in effector cells. The present study aimed to examine the suppressive effect of SP-A on macrophage-mediated xenogeneic rejection. Naive SECs and SPA-transfected SECs (SEC/SP-A) were co-cultured with THP-1 cells and cytotoxicity was evaluated. To investigate the effect of SP-A on phagocytosis, human macrophages were co-cultured with SEC or SEC/SP-A, and the extent of phagocytosis and production of reactive oxygen species were assessed via flow cytometry. The mRNA expression levels of inflammatory cytokines in macrophages were determined using reverse transcription-PCR. Additionally, the effects of THP-1-Lucia NF-κB cells on transcription factors were evaluated. The cytotoxicity and phagocytosis of SEC/SP-A were significantly decreased compared with those of naive SEC. Furthermore, the co-culture of human macrophages with SEC/SP-A decreased reactive oxygen species production, and the mRNA expression levels of TNFα were decreased in macrophages, whereas those of IL-10 were increased. In addition, NF-κB transcription was decreased in SEC/SP-A compared with that in SEC. In conclusion, the ectopic expression of human SP-A in porcine cells represents an attractive method for suppressing macrophage-mediated cytotoxicity.
巨噬细胞介导的异种排斥是一个主要的免疫障碍。我们最近报道，猪内皮细胞（SECs）上的膜型表面活性蛋白-D（SP-D）可抑制巨噬细胞介导的排斥反应。与SP-D类似，表面活性蛋白-A（SP-A）的碳水化合物识别结构域可在效应细胞中诱导抑制性信号。本研究旨在检测SP-A对巨噬细胞介导的异种排斥反应的抑制作用。将未处理的SECs和转染了SP-A的SECs（SEC/SP-A）与THP-1细胞共培养，并评估细胞毒性。为了研究SP-A对吞噬作用的影响，将人巨噬细胞与SEC或SEC/SP-A共培养，并通过流式细胞术评估吞噬程度和活性氧的产生。使用逆转录聚合酶链反应测定巨噬细胞中炎性细胞因子的mRNA表达水平。此外，评估了THP-1-Lucia NF-κB细胞对转录因子的影响。与未处理的SEC相比，SEC/SP-A的细胞毒性和吞噬作用显著降低。此外，人巨噬细胞与SEC/SP-A共培养可降低活性氧的产生，巨噬细胞中TNFα的mRNA表达水平降低，而IL-10的表达水平升高。此外，与SEC相比，SEC/SP-A中的NF-κB转录降低。总之，人SP-A在猪细胞中的异位表达是一种抑制巨噬细胞介导的细胞毒性的有吸引力的方法。
