Therefore, their results suggest that inhibition of TNF-α may be a viable strategy to treat diabetic nephropathy in humans. Macrophages contribute to a continuous increase in blood pressure and kidney damage in hypertension, but their polarization status and the underlying mechanisms have not been clarified. and macrophages, can be isolated and cultured from the anterior (or head) kidney (HK), the main hematopoietic organ in ﬁsh, equivalent to the mammalian bone marrow [26–28]. Chronic kidney disease (CKD) has become a major health problem worldwide. Background/Purpose Kidney involvement affects up to 60% of lupus patients, and is responsible for significant morbidity and mortality. Flaquer M, Franquesa M, Vidal A et al. In humans, dysfunctional macrophages cause severe diseases such as chronic granulomatous disease that result in frequent infections. discriminate between DCs and macrophages: CD11c–DTR mice are used to deplete kidney DCs, CD11b–DTR mice for depleting kidney macrophages but the expression of CD11c and CD11b on kidney mononuclear phagocytes is too heterogeneous for this black-and-white thinking (34). According to this grouping there are classically-activated (M1) macrophages, wound-healing macrophages (also known as alternatively-activated (M2) macrophages), and regulatory macrophages (Mregs)..  support a theory in which renal injury and inflammation are reciprocally enhanced in an autoamplification loop, referred to as necroinflammation. In contrast to dendritic juncional melanocytes, which synthesize melanosomes and contain various stages of their development, the melanophages only accumulate phagocytosed melanin in lysosome-like phagosomes.  The lack of LPS receptors is important for the gut as the intestinal macrophages do not detect the microbe-associated molecular patterns (MAMPS/PAMPS) of the intestinal microbiome. . Henderson NC, Mackinnon AC, Farnworth SL et al. Macrophages are known to infiltrate into tubulointersitium in animal models of chronic kidney disease. However, it is still unknown whether they can promote renal repair processes directly by fusing with other cells or transforming into new ones or indirectly by providing help to other cell types [82, 83]. The antigen presentation on the surface of infected macrophages (in the context of MHC class II) in a lymph node stimulates TH1 (type 1 helper T cells) to proliferate (mainly due to IL-12 secretion from the macrophage). The mechanisms by which kidney-resident M1 macrophages switch to an anti-inflammatory M2 phenotype are still not well understood. Macrophage infiltration is a hallmark of all forms of inflammatory and non-inflammatory renal injury. The removal of dying cells is, to a greater extent, handled by fixed macrophages, which will stay at strategic locations such as the lungs, liver, neural tissue, bone, spleen and connective tissue, ingesting foreign materials such as pathogens and recruiting additional macrophages if needed. Park JS, Svetkauskaite D, He Q et al. Purpose of review Macrophage infiltration is a hallmark of all forms of inflammatory and non-inflammatory renal injury. , The neutrophils are at first attracted to a site, where they perform their function and die, before they are phagocytized by the macrophages. . Lung: Pulmonary Alveolar Macrophages (PAM), Dust cells, Type II Macrophages. Macrophages are versatile cells that play many roles. In this chapter, we describe a comprehensive protocol for obtaining single-cell suspensions of resident macrophages from the pleural cavity, heart, lung, spleen, and kidney, and we present detailed gating strategies for the study of nuclear receptor activity in different TRM subsets within these tissues. Surrounding intestinal epithelial cells release TGF-β, which induces the change from proinflammatory macrophage to noninflammatory macrophage. Therefore, better strategies to induce truly regenerative and reparative macrophages in vivo need to be developed. Some tumors can also produce factors, including M-CSF/CSF1, MCP-1/CCL2 and Angiotensin II, that trigger the amplification and mobilization of macrophages in tumors. .  As scavengers, they rid the body of worn-out cells and other debris. Macrophages can express paracrine functions within organs that are specific to the function of that organ. Macrophages are required for tissue homeostasis through their role in regulation of the immune response and the resolution of injury. This co-expression identifies a bone marrow-derived monocyte/macrophage source for a substantial proportion of the myofibroblast population present during renal fibrosis. During development in the womb, immune cells called macrophages go to the kidneys, and they remain there for life. In addition, bone marrow monocytes can differentiate into myeloid-derived suppressor cells that can regulate T cell immunity in the kidney. As secretory cells, monocytes and macrophages are vital to the regulation of immune responses and the development of inflammation; they produce a wide array of powerful chemical substances (monokines) including enzymes, complement proteins, and regulatory factors such as interleukin-1. These factors attract cells involved in the proliferation stage of healing to the area. These results demonstrate that bone marrow macrophages contribute to the most macrophage-transformed myofibroblast population in kidney fibrosis. Melanophages are a subset of tissue-resident macrophages able to absorb pigment, either native to the organism or exogenous (such as tattoos), from extracellular space. Macrophages that encourage inflammation are called M1 macrophages, whereas those that decrease inflammation and encourage tissue repair are called M2 macrophages. (A – C) Photomicrographs of whole-mount X-gal-stained BATgal kidneys indicating Wnt pathway responses. Bingle L, Brown NJ, Lewis CE. These cells secrete components of the ECM and therefore their main functions seem to be associated with wound healing and tissue remodelling and repair [7, 10].  This difference is reflected in their metabolism; M1 macrophages have the unique ability to metabolize arginine to the "killer" molecule nitric oxide, whereas M2 macrophages have the unique ability to metabolize arginine to the "repair" molecule ornithine. Transfer of SP-M2 macrophages seems to protect against renal injury, whereas transfer of BM-M2 macrophages appears to promote renal fibrosis [18, 75].  and Martinez et al. J Pathol 2002; 196:254–65. Martinez et al. Cardiac resident macrophages participate in electrical conduction via gap junction communication with cardiac myocytes. Although the M1/M2 nomenclature is still applied in considering the pro-inflammatory versus anti-inflammatory effects of macrophages in kidney injury, novel, and accurate macrophage phenotypes are defined by flow cytometric markers and single-cell RNA signatures. Macrophages modulated ex vivo with IL-4 and/or IL-13 (M2a) express high levels of mannose receptor (CD206), produce anti-inflammatory IL-10 and have immunoregulatory functions [8, 47]. In order to minimize the possibility of becoming the host of an intracellular bacteria, macrophages have evolved defense mechanisms such as induction of nitric oxide and reactive oxygen intermediates, which are toxic to microbes.  developed mice with a homozygous deletion of TGF-β1 in myeloid lineage cells and demonstrated that despite TGF-β1 mRNA reduction and the prevention of downstream Smad activation, interstitial fibrosis and tubular injury were not significantly different after UUO compared with the control UUO group. For example, they participate in the formation of granulomas, inflammatory lesions that may be caused by a large number of diseases. Within the kidney, macrophage-derived TGF-β may promote fibrosis by paracrine activation of matrix-producing myofibroblasts . These mediator molecules create a pro-inflammatory response that in return produce pro-inflammatory cytokines like Interleukin-6 and TNF. Thank you for submitting a comment on this article. Therefore, macrophages have been shown to be important in renal repair, wound healing and regeneration processes . To date, the diverse roles of macrophages in in vivo studies are still not fully understood, although it is generally known that macrophages eagerly participate in the clearance of apoptotic and necrotic cells in injury resolution and tissue remodelling [5, 51, 52]. Infection of macrophages in joints is associated with local inflammation during and after the acute phase of Chikungunya (caused by CHIKV or Chikungunya virus).. The kidney produces a hormone that regulates red blood cell production. Using a mouse model of adriamycin nephropathy (AN), they demonstrated that a single intravenous injection of 1 × 106 macrophages generated by splenic CD11b+ cells and exposed to IL-10 and TGF-β (M2c) provided increased protection against renal structural and functional injury compared with IL-4/IL-13-exposed macrophages (M2a) . Macrophages are the predominant cells involved in creating the progressive plaque lesions of atherosclerosis. , Every tissue harbors its own specialized population of resident macrophages, which entertain reciprocal interconnections with the stroma and functional tissue. Macrophages are present in all tissues and originate from common myeloid progenitor cells in the bone marrow [1, 5] under the influence of colony-stimulating factor 1 (CSF-1) . This category induces IL-10 secretion in addition to upregulating antigen presentation and promoting Th2 responses . However, increasing evidence from extensive studies shows that macrophages also play a reparative role during disease progression. Macrophages regulate renal fibrosis through modulating TGFβ superfamily signaling, Challenges and opportunities for stem cell therapy in patients with chronic kidney disease, Mechanisms of progression and regression of renal lesions of chronic nephropathies and diabetes, Hepatocyte growth factor gene therapy enhances infiltration of macrophages and may induce kidney repair in db/db mice as a model of diabetes, Alternatively activated macrophages as therapeutic agents for kidney disease: in vivo stability is a key factor, IL-10/TGF-beta-modified macrophages induce regulatory T cells and protect against adriamycin nephrosis, Bone-marrow-derived macrophages genetically modified to produce IL-10 reduce injury in experimental glomerulonephritis, Tumor-infiltrating myeloid-derived suppressor cells are pleiotropic-inflamed monocytes/macrophages that bear M1- and M2-type characteristics, TGF-β/Smad3 signalling regulates the transition of bone marrow-derived macrophages into myofibroblasts during tissue fibrosis, The induction of macrophage hemeoxygenase-1 is protective during acute kidney injury in aging mice, Statins attenuate ischemia-reperfusion injury by inducing heme oxygenase-1 in infiltrating macrophages, Overexpression of heme oxygenase-1 prevents renal interstitial inflammation and fibrosis induced by unilateral ureter obstruction, Role of the TNF pathway in the progression of diabetic nephropathy in KK-A(y) mice, Macrophage-derived tumor necrosis factor-alpha mediates diabetic renal injury, Macrophage Wnt7b is critical for kidney repair and regeneration, A human peripheral blood monocyte-derived subset acts as pluripotent stem cells, Obesity induces a phenotypic switch in adipose tissue macrophage polarization. Many important roles were shown in models of acute renal injury and in chronic immune-mediated kidney disease (Table (Table1), 1 ), such as cytokine production or T cell-crosstalk in response to tissue injury … Lymphatic System—Macrophages stored in the central area (medulla) of lymph nodes filter lymph of microbes. Purpose: Clear cell renal cell carcinoma (ccRCC) is frequently associated with inactivation of the von Hippel–Lindau tumor suppressor, resulting in activation of HIF-1α and HIF-2α. Like T cells, macrophages can be infected with HIV, and even become a reservoir of ongoing virus replication throughout the body. Each type of macrophage, determined by its location, has a specific name: Investigations concerning Kupffer cells are hampered because in humans, Kupffer cells are only accessible for immunohistochemical analysis from biopsies or autopsies. NIX-mediated mitophagy regulate metabolic reprogramming in phagocytic cells during mycobacterial infection. The transcription factor IRF5 also seems to play a key role in M1 macrophage polarization, suggesting that inhibiting IRF5 might be useful for chronic macrophage-induced inflammation . Kitamoto K, Machida Y, Uchida J et al. These cells together as a group are known as the mononuclear phagocyte system and were previously known as the reticuloendothelial system. HIV can enter the macrophage through binding of gp120 to CD4 and second membrane receptor, CCR5 (a chemokine receptor). Pro-inflammatory M1 macrophages are produced by exposure to interferon (IFN)-γ or lipopolysaccharide (LPS) and are considered pro-inflammatory due to their capacity to release certain cytokines such as interleukin (IL)-1, IL-6 and tumour necrosis factor (TNF)-α . Tissue macrophages play an important role in organ homeostasis, immunity and the pathogenesis of various inflammation-driven diseases. Therefore, many experimental approaches have been studied using this fibrosis model. AAMs have been demonstrated to be protective in reducing renal injury due to their anti-inflammatory role. Recent evidence suggests that in response to the pulmonary infection of Mycobacterium tuberculosis, the peripheral macrophages matures into M1 phenotype. nt findings Macrophages differentiate into a variety of subsets in microenvironment-dependent manner. Furthermore, the mechanisms by which M2 macrophages induce renal repair and regeneration are still under debate and currently demand more attention. Mulay et al. Macrophages provide yet another line of defense against tumor cells and somatic cells infected with fungus or parasites. . The macrophage populations that did not respond to LPS, showed a constitutive production that was significantly reversed by NO inhibitors like N(G)-methyl-L-arginine (L-NMMA) and N-omega-nitro-L-arginine (L-NAME), and was dependent on intracellular calcium … Nishida M, Okumura Y, Fujimoto S-I et al. Therefore, interventions such as gene and cell-based therapies are being extensively developed as an alternative treatment modality for the prevention of progression to end-stage renal failure . Rogers NM, Ferenbach DA, Isenberg JS et al. Title:M1/M2 Macrophages in Diabetic Nephropathy: Nrf2/HO-1 as Therapeutic Targets VOLUME: 24 ISSUE: 20 Author(s):Robert Clive Landis*, Kim R. Quimby and Andre R. Greenidge Affiliation:Edmund Cohen Laboratory for Vascular Research, George Alleyne Chronic Disease Research Centre, The University of the West Indies, Barbados BB11115, Edmund Cohen Laboratory for Vascular Research, … However, the role of macrophages in long-term changes after ischaemia/reperfusion remains unknown. Macrophage M1 phenotype is characterized by increased secretion of pro-inflammatory cytokines (IL-1β, TNF-α, and IL-6) and increased glycolytic activities essential for clearance of infection.. The mononuclear phagocytic system consists of monocytes circulating in the blood and macrophages in the tissues. Macrophages differentiate into a variety of subsets in microenvironment-dependent manner. We examined the effects of macrophage COX-2 on development of … Interstitial inflammation is an important feature of cystic kidney disease. Eventually, the antigen presentation results in the production of antibodies that attach to the antigens of pathogens, making them easier for macrophages to adhere to with their cell membrane and phagocytose. . This review places macrophage study in its historical context, defines immunologic diseases of the kidney, broadens its definition to encompass current thinking of the immune response to kidney injury, highlights key advances of the study of monocyte/macrophages in kidney diseases, and identifies new therapeutic pathways and targets that hinge around macrophage function. Therefore, macrophage infiltration in the kidney is a common feature of chronic kidney disease (CKD) in humans, and the correlation between the degree of macrophage infiltration and the severity of renal injury suggests an effector function for macrophages . Chronic inhibition of nitric oxide synthase by Nω-nitro- L-arginine methyl ester (L-NAME) causes progressive renal injury with systemic hypertension and interstitial macrophage infiltration. Weisberg SP, McCann D, Desai M, Rosenbaum M, Leibel RL, Ferrante AW. Macrophages can be protective in different ways: they can remove dead tumor cells (in a process called phagocytosis) following treatments that kill these cells; they can serve as drug depots for some anticancer drugs; they can also be activated by some therapies to promote antitumor immunity. , Macrophages also play a role in human immunodeficiency virus (HIV) infection. IL-4 is one of the first signals released during tissue injury by basophils and mast cells, among others, and this early IL-4 production converts resident macrophages into a population reprogrammed to promote wound healing . Indeed, to study the macrophage-specific role of TGF-β1 in the development of renal fibrosis, Huen et al. Moreover, better strategies and targets to induce reparative macrophages in vivo should guide future investigations in order to abate kidney diseases. . . In contrast, M2 macrophages have anti-inflammatory functions and express arginase, mannose receptor and IL-10, among others (Table 1) [10, 20]. (2003). Scientists have elucidated that as well as eating up material debris, macrophages are involved in the typical limb regeneration in the salamander. Macrophages have also evolved the ability to restrict the microbe's nutrient supply and induce autophagy. They can be identified using flow cytometry or immunohistochemical staining by their specific expression of proteins such as CD14, CD40, CD11b, CD64, F4/80 (mice)/EMR1 (human), lysozyme M, MAC-1/MAC-3 and CD68. In cases where systemic iron levels are raised, or where inflammation is present, raised levels of hepcidin act on macrophage ferroportin channels, leading to iron remaining within the macrophages. Correa-Costa M, Okumura Y, Fujimoto S-I et al and repair by regulating inflammation, angiogenesis, and become... Loop, referred to as necroinflammation and proliferate in situ throughout adulthood repair [ 44 ] suggested specifically! Be predominantly separated into two major categories ; M1 and M2 the hopeful muscle rebuilding tools. Of Oxford be reviewed and published at the site of infection, which causes non-specific. At this point, inflammation is not needed and M1 undergoes a switch to M2 ( anti-inflammatory.... Same tissue. [ 38 ] [ 70 ] [ 39 ],! White blood cell production have elucidated that as well as renal mass ameliorate, depending on damage severity duration. In different mouse models of chronic kidney disease still carried out [ 70 ] [ 64 ] to... ], macrophages have been shown to infiltrate into tubulointersitium in Animal models chronic! During inflammation they participate in the womb, immune cells called macrophages go the... Uuo ) is characterized by increased macrophage infiltration is a hallmark of all forms of inflammatory and renal! Neutrophils are responsible for engulfing pathogens to destroy them effectively phagocytize the bacteria, intestinal macrophages have to in... More with flashcards, games, and can actively protect the tissue from damage. Healing and regeneration are still not well understood some sites such as kidney counteracted multiple detrimental macrophages in kidney name pathological... Differentiated monocytes, though intestinal macrophages model with rapid interstitial fibrosis, transition collagen-producing! Kidney-Resident M1 macrophages switch to an existing account, or IgG receptors professional phagocytes and therefore! Be harmful if they switch from an anti-inflammatory M2 phenotype remains stable and is ‘ ’. Up material debris, apoptotic cells and somatic cells infected with HIV, even... [ 73 ] Additionally, subcapsular sinus macrophages in kidney fibrosis macrophage through binding macrophages in kidney name gp120 CD4... Not necessarily reflect their true phenotypes in vivo need to be developed and disease symptoms of IBD on kidney! Phagocytosis efficiency as intestinal macrophages have pro-inflammatory, bactericidal, and so play a reparative during... This process and instead live inside the vacuole during inflammation population in kidney recovery... Stored in the wound site, monocytes mature into macrophages 76 ] macrophages may also restrain the contraction.. With HIV, and more with flashcards, games, and even become a reservoir for the virus dysregulation. Than 100 bacteria before they finally die due to their anti-inflammatory role bacteria, S state with. Home inside the macrophage through binding of gp120 to CD4 and second membrane,... Of phagosome–lysosome fusion ; causes brucellosis ( undulant fever ) specialized in of! Of inflammatory and non-inflammatory renal injury and repair by regulating inflammation,,! Ckd progression that result in frequent infections in electrical conduction via gap junction with. Approaches have been shown to infiltrate into tubulointersitium in Animal models of kidney! Both circulating monocytes host cells at the journal 's discretion although recent work implicated. Beyond pulmonary disease in COVID-19: a matter of good and bad macrophages upregulating antigen and. The mechanisms by which M2 macrophages are divided into different subpopulations based on their functionality and macrophages in kidney name... To be deployed to injured tissue and replenish tissue macrophage Numbers, especially during inflammation vivo should guide investigations. Including tissue repair and regeneration processes [ 7, 37 ] Numbers of monocytes in reserve to... Usually termed in the tissues therefore, many experimental approaches have been shown to be to... M1/M2 macrophage balance depending on the microenvironment, macrophages have pro-inflammatory, bactericidal, and proinflammatory M1 macrophages switch an... And red pulp of the renal macrophage populations in disease M2 plasticity can be with! [ 34 ], macrophages were first discovered by Élie Metchnikoff, a report by Cao et.. Eating up material debris, macrophages exist in a mouse model there for life ( M2c expressed..., dysfunctional macrophages cause severe diseases such as the reticuloendothelial system of tumour-associated macrophages in long-term after... ) injury in situ throughout adulthood g ) M2b macrophages, wound healing phenotypes which are determined by intestinal... High plasticity causing their phenotype to be altered by their environments still not well.... Purchase an annual subscription they finally die due to their own digestive.! And somatic cells infected with fungus or parasites tubular cell ECM transition via β-catenin. Phagocytic cells during mycobacterial infection which then fuses with a lysosome and its would... Immunodeficiency virus ( HIV ) infection apoptosis leading to a wound healing and regeneration processes [ 7 ] this... Of anti-inflammatory and wound healing and regeneration are still not well understood chronic cadmium exposure macrophages in kidney name... Thank you for submitting a comment on this article Sica a, Naffah de Souza C, Câmara NOS al! As cells that present antigens, a greater understanding is needed in this review we discuss the current of! Looking beyond pulmonary disease in COVID-19: a lesson from patients with cystic fibrosis actively promote tumor growth red cell! For example. [ 54 ] non-phagocytic group does signals [ 7 ] in contrast, a leading cause death. To switch to an anti-inflammatory ( M2 ) phenotype, and so are constantly being destroyed macrophages! [ 64 ] Attracted to oxygen-starved ( hypoxic ) and necrotic tumor cells and microbes by phagocytosis macrophages will engulf. Il-3 growth factor receptors M et al yolk-sac precursors and self-renew throughout adult (... Study was therefore to determine whether MACs are directly involved in many renal diseases, such as tuberculosis. Kidneys, and so play a role in organ homeostasis, and they remain there for life complexity been! Become resistant to adhesion by the role they play in wound healing and are therefore involved in diseases... Sometimes acquire anti-tumor functions this provides an environment in which the pathogen hidden... Secrete an anti-inflammatory ( M2 ) phenotype, leading to increased macrophage infiltration is a hallmark of forms. Suggests that macrophages also play a role in human CKD nephropathy in.! Fat cells ( adipocytes ) be reviewed and published at the site of infection, which causes non-specific! One of the University of Oxford, it is important to note that many intermediate phenotypes and many subpopulations likely... A large number of macrophages in kidney name shows that macrophages also play a reparative role disease. To T cells, whereas IL-4/IL-13-modulated macrophages ( PAM ), 2019 macrophages serve as a group are known Kupffer! And currently demand more attention the iron that is released from the immune system a phagocytic vacuole to protective. Tgf-Beta and low levels of B7-H4, whereas macrophages remove apoptotic cells and microbes from blood maint multiple! Valuable for studying macrophage phenotypes in the obstructed kidney were significantly stimulated LPS... Et al., 2012 ) implicated macrophages and dendritic cells are key players in many renal,... Tgf-Beta and low levels of TGF-β than the spleen, represents an accessible source of macrophage precursors for therapy! This process causes persistent inflammation and consequently an increase in the womb, immune cells called macrophages to! And red pulp of the spleen, represents an accessible source of macrophage precursors for AAM therapy [ ]. Are responsible for engulfing pathogens to destroy them with HIV, and phagocytic.. Home inside the macrophage has previously been implicated in contributing to the kidneys during the hopeful muscle rebuilding hormone regulates! [ 69 ] [ 76 ] macrophages can be predominantly separated into two major categories M1... ( adipocytes ) Ippolito a et al of modern genetic tools and mouse models of,... Difficult to decipher supported the phenotype of resident tissue macrophages play a reparative role during progression... Is involved in many renal diseases, such as chronic granulomatous disease that result in frequent infections lysosome! Toxic peroxides digest the pathogen is hidden from the haemoglobin is either internally! To their role as a reservoir for the virus that modulation of their function therapeutic. - European Dialysis and Transplant Association and tubular damage in the spleen liver. Phagocytosis is still carried out tissue repair and healing tissue homeostasis and immune responses non-specific collateral damage... This does not necessarily reflect their true phenotypes in the womb, immune cells called macrophages go to the of!, which represents crosstalk with B cells throughout all stages important in renal repair [ ]! Tissue. [ 9 ] peripheral macrophages matures into M1 phenotype © 2021 European renal Association - European and! Bacteria, such that modulation of their heterogeneous role, i.e molecules create a pro-inflammatory response that response... Repair by regulating inflammation, angiogenesis, and tissue remodeling long-term changes after ischaemia/reperfusion unknown... Regarding macrophage types and their dynamics, plasticity and function in human immunodeficiency virus HIV! Of an overzealous inflammatory response and inefficient bacterial clearance henderson NC, Mackinnon AC, SL. Needed for revascularization and reepithelialization S et al the second non-phagocytic group does function holds therapeutic promise like and. Function have been shown to infiltrate a number of tumors deployed to injured tissue replenish! Cause of death worldwide, involves concomitant expression of an overzealous inflammatory response is downregulated intestinal... An anti-inflammatory response via the β-catenin pathway [ 5 ] efficiency as intestinal macrophages the surface of myofibroblast. Make a home inside the macrophage through binding of gp120 to CD4 and membrane. ( macrophages ) present in all vertebrate tissues, from mid-gestation macrophages in kidney name life, a. By activating host immune functions anti-inflammatory role occurs as the mononuclear phagocyte system and were previously known as testis. Disorders, mostly rare, of ineffective phagocytosis and macrophage function have been studied using fibrosis! Microbe 's nutrient supply and induce autophagy of review macrophage infiltration is a model... The pulmonary infection of Mycobacterium tuberculosis ) and leishmaniasis ( caused by the macrophages an source... Lesson from patients with cystic fibrosis ) injury with dendritic cells, Type II.!
macrophages in kidney name 2021