Macrophages and kidney transplantation / 器官移植

Kidney transplantation is the optimal treatment for patients with end-stage renal disease, whereas long-term survival of renal allografts remains a challenging issue. Renal ischemia-reperfusion injury (IRI) and rejection of renal allografts are considered as important influencing factors of long-term survival of renal allografts, which are regulated by innate and adaptive immune cells. Macrophages are one type of innate immune cells that could assist initiating adaptive immunity and are divided into M1, M2 and regulatory macrophages. Previous studies have revealed that M1 macrophages may aggravate renal IRI and acute T cell-mediated rejection (TCMR). However, M2 macrophages may mitigate renal IRI and acute TCMR, whereas it is positively correlated with antibody-mediated rejection (AMR). Regulatory macrophages are a special subgroup of macrophages, which may induce immune tolerance in organ transplantation and have promising clinical application prospects and basic scientific research value. In this article, the relationship among macrophage typing, macrophages and renal IRI, rejection of renal allografts, regulatory macrophages and immune tolerance was reviewed, and the potential mechanism was analyzed, aiming to induce changes in macrophage subtypes or eliminate specific subtypes of macrophages, thereby improving clinical prognosis of the recipients and long-term survival of renal allografts.

Recent progress on the roles of DAMP and NET in organ ischemia-reperfusion injury / 器官移植

Ischemia-reperfusion injury (IRI) is a common pathophysiological phenomenon, secondary to multiple pathological processes, such as organ transplantation, acute kidney injury and myocardial infarction. IRI may significantly aggravate the severity of diseases and increase the fatality of patients. Aseptic inflammation is one of the critical mechanisms of IRI. Damage-associated molecular pattern (DAMP) is a pivotal substance, which mediates aseptic inflammation. After released into extracellular space, it could effectively activate the immune system, and initiate and maintain the inflammatory responses by binding with pattern recognition receptor (PRR). Neutrophil extracellular trap (NET) is a DNA-based network structure released by neutrophils during the process of inflammatory responses, which contains histones and multiple granular proteins. Recent studies have demonstrated that DAMP and NET may aggravate IRI via aseptic inflammation. In this article, relevant studies of DAMP, NET and their relationship in IRI were reviewed, which was of great significance for understanding the pathophysiological mechanism of IRI and studying the corresponding prevention and treatment strategies.