AUTHOR=Hang Zhou , Wei Jintao , Zheng Ming , Gui Zeping , Chen Hao , Sun Li , Fei Shuang , Han Zhijian , Tao Jun , Wang Zijie , Tan Ruoyun , Gu Min 

TITLE=Iguratimod Attenuates Macrophage Polarization and Antibody-Mediated Rejection After Renal Transplant by Regulating KLF4

JOURNAL=Frontiers in Pharmacology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2022.865363

DOI=10.3389/fphar.2022.865363

ISSN=1663-9812

ABSTRACT=Background: This study was to explore the effect and mechanism of Iguratimod (IGT) on M1 macrophage polarization and ABMR after renal transplant.
Methods: Bioinformatics analysis was performed using three public databases derived from GEO database. Sprague Dawley (SD) rats was pre-sensitized with donors of Wistar rats in skin transplantation and rat renal transplant ABMR model was established from donors to skin pre-sensitized recipients. Subsequently, IGT was treated on the ABMR model. Routine staining and immunofluorescence (IF) staining were used to observe the pathological changes in each group; flow cytometry was used to detect the changes of DSA titers in peripheral blood. In addition, Bone Marrow Derived Macrophage (BMDM) was extracted and interfered with IGT to explore the effect of IGT in vivo. PCR, IF staining and western blot was used to detect the expression of related genes and proteins.
Results: Bioinformatics analysis revealed several immune cells were significantly infiltrated in the ABMR allograft, while M1 macrophage was noticed with the most significance. Results of IF staining and PCR proved the findings in bioinformatics analysis. Based on this, IGT was observed to significantly attenuate the degree of peritubular capillary vasculitis and arteriolitis in rat renal transplant ABMR model, while decrease the expression of C4d and reduce the titer of DSA. Results in vitro suggested that M1 macrophage-related transcripts and proteins were significantly reduced by the treatment of IGT in a dose- and time-dependent manner. Furthermore, IGT intervention could remarkably decrease the expression of KLF4.
Conclusion: Polarization of M1 macrophages may aggravate ABMR after renal transplant by promoting DSA-mediated endothelial cell injury and IGT may attenuate the pathogenesis of ABMR by targeting KLF4.