Galectin-9(Tim-3L)significantly attenuates allogeneic immune response in mice / 中华微生物学和免疫学杂志

ABSTRACT

Objective To explore the subcellular localization of Galectin-9 and its effect on allogeneic immune response.Methods The plasmid pEGFP-N1 was inserted with Galectin-9 fragment which was amplified from pBKCMV-Galectin-9 by PCR.The recombinant plagmid wag then transfected into CHO cells using JetPEI in vitro.The cells were cultured in G418 selecting mediam to obtain the stably-transfected cells.The transcription and expression of Galectin-9 gene were verified by immunohistochemical staining and RT-PCR.The solid-phase transgenic CHO cells or freshly-cultured supernatant wag added into the mixed lymphocyte response system to detect the inhibitory effect of Galectin-9.Galectin-9 protein wag administered intraperitoneally for 7d consecutively.Results The expression of Galectin-9 wag localized in the cytosol of CHO.The allogeneic mix lymphocyte proliferation was dose-dependently inhibited by the freshly-cultured supernatant from stably-transfected CHO cells.Furthermore,the supernatant from stably-transfected CHO cells dose-dependently inhibited the level of IL-2.The inhibitory effect could be reversed by Tim-3-Fc blocking.Administration of Galectin-9 significantly prolonged the survival of allogeneic cardiac transplants[(22.7±1.2)d vs(7.2±0.4)d)].Conclusion Galectin-9 may be secreted in physical situation to exert its immunomodulatory function on allogeneic immune response.Furthermore.Galectin-9 may be a novel therapeutic drug in transplant medicine.