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Frontiers in Immunology 2019We are living through an unprecedented accumulation of data on gene expression by macrophages, reflecting their origin, distribution, and localization within all organs... (Review)
Review
We are living through an unprecedented accumulation of data on gene expression by macrophages, reflecting their origin, distribution, and localization within all organs of the body. While the extensive heterogeneity of the cells of the mononuclear phagocyte system is evident, the functional significance of their diversity remains incomplete, nor is the mechanism of diversification understood. In this essay we review some of the implications of what we know, and draw attention to issues to be clarified in further research, taking advantage of the powerful genetic, cellular, and molecular tools now available. Our thesis is that macrophage specialization and functions go far beyond immunobiology, while remaining an essential contributor to innate as well as adaptive immunity.
Topics: Animals; Antigens; Cell Differentiation; Cell Proliferation; Gene Expression; Humans; Mononuclear Phagocyte System
PubMed: 31447860
DOI: 10.3389/fimmu.2019.01893 -
Brain Pathology (Zurich, Switzerland) Mar 2023Ischemic stroke (IS) is a major cause of disability and death in adults, and the immune response plays an indispensable role in its pathological process. After the onset... (Review)
Review
Ischemic stroke (IS) is a major cause of disability and death in adults, and the immune response plays an indispensable role in its pathological process. After the onset of IS, an inflammatory storm, with the infiltration and mobilization of the mononuclear phagocyte system (MPS), is triggered in the brain. Microglia are rapidly activated in situ, followed by waves of circulating monocytes into the ischemic area. Activated microglia and monocytes/macrophages are mainly distributed in the peri-infarct area. These cells have similar morphology and functions, such as secreting cytokines and phagocytosis. Previously, the presence of the MPS was considered a marker of an exacerbated inflammatory response that contributes to brain damage. However, recent studies have suggested a rather complicated role of the MPS in IS. Here, we reviewed articles focusing on various functions of the MPS among different phases of IS, including recruitment, polarization, phagocytosis, angiogenesis, and interaction with other types of cells. Moreover, due to the characteristics of the MPS, we also noted clinical research addressing alterations in the MPS as potential biomarkers for IS patients for the purposes of predicting prognosis and developing novel therapeutic strategies.
Topics: Humans; Ischemic Stroke; Mononuclear Phagocyte System; Macrophages; Microglia; Monocytes; Stroke
PubMed: 36755470
DOI: 10.1111/bpa.13151 -
Shock (Augusta, Ga.) Aug 2013Burn is one of the most common and devastating forms of trauma. Major burn injury disturbs the immune system, resulting in marked alterations in bone marrow... (Review)
Review
Burn is one of the most common and devastating forms of trauma. Major burn injury disturbs the immune system, resulting in marked alterations in bone marrow hematopoiesis and a progressive suppression of the immune response, which are thought to contribute to increased susceptibility to secondary infections and the development of sepsis. Immunosuppression in patients with severe burn and sepsis leads to high morbidity and mortality in these patients. mononuclear phagocytes system (MPS) is a critical component of the innate immune response and plays key roles in burn immunity. These phagocytes are the first cellular responders to severe burn injury after acute disruption of the skin barrier. They are not only able to internalize and digest bacteria and dead cells and scavenge toxic compounds produced by metabolism, but also able to initiate an adaptive immune response. Severe burn and sepsis profoundly inhibit the functions of dendritic cells, monocytes, and macrophages. Adoptive transfer of MPS or stem cells to patients with severe burn and sepsis that aim to restore MPS function is promising. A better understanding of the roles played by MPS in the pathophysiology of severe burn and sepsis will guarantee a more rational and effective immunotherapy of patients with severe burn and sepsis.
Topics: Animals; Burns; Humans; Mononuclear Phagocyte System; Sepsis
PubMed: 23860581
DOI: 10.1097/SHK.0b013e318299f774 -
Frontiers in Immunology 2018CD1d-restricted Natural Killer T (NKT) cells are regarded as sentinels of tissue integrity by sensing local cell stress and damage. This occurs via recognition of... (Review)
Review
CD1d-restricted Natural Killer T (NKT) cells are regarded as sentinels of tissue integrity by sensing local cell stress and damage. This occurs via recognition of CD1d-restricted lipid antigens, generated by stress-related metabolic changes, and stimulation by inflammatory cytokines, such as IL-12 and IL-18. Increasing evidence suggest that this occurs mainly upon NKT cell interaction with CD1d-expressing cells of the Mononuclear Phagocytic System, i.e., monocytes, macrophages and DCs, which patrol parenchymatous organs and mucosae to maintain tissue homeostasis and immune surveillance. In this review, we discuss critical examples of this crosstalk, presenting the known underlying mechanisms and their effects on both cell types and the environment, and suggest that the interaction with CD1d-expressing mononuclear phagocytes in tissues is the fundamental job of NKT cells.
Topics: Cell Communication; Dendritic Cells; Disease Susceptibility; Humans; Lymphoid Tissue; Mononuclear Phagocyte System; Myeloid Cells; Natural Killer T-Cells; Neoplasms; Organ Specificity; Phagocytes; Tumor Microenvironment
PubMed: 30369933
DOI: 10.3389/fimmu.2018.02375 -
Seminars in Immunopathology Mar 2016The Leishmania granuloma shares some, though not all, properties with that formed following mycobacterial infection. As a simplified, noncaseating granuloma composed of... (Review)
Review
The Leishmania granuloma shares some, though not all, properties with that formed following mycobacterial infection. As a simplified, noncaseating granuloma composed of relatively few and largely mononuclear cell populations, it provides a tractable model system to investigate intra-granuloma cellular dynamics, immune regulation, and antimicrobial resistance. Here, the occurrence of granulomatous pathology across the spectrum of leishmaniasis, in humans and animal reservoir hosts, is first described. However, this review focuses on the process of hepatic granuloma formation as studied in rodent models of visceral leishmaniasis, starting from the initial infection of Kupffer cells to the involution of the granuloma after pathogen clearance. It describes how the application of intravital imaging and the use of computational modeling have changed some of our thoughts on granuloma function, and illustrates how host-directed therapies have been used to manipulate granuloma form and function for therapeutic benefit. Where appropriate, lessons that may be equally applicable across the spectrum of granulomatous diseases are highlighted.
Topics: Animals; Antiprotozoal Agents; Chemokines; Cytokines; Granuloma; Humans; Immune System; Leishmania; Leishmaniasis; Liver; Lymphoid Tissue; Mice; Mononuclear Phagocyte System
PubMed: 26678994
DOI: 10.1007/s00281-015-0548-7 -
Acta Cirurgica Brasileira 2023To study the uptake capacity of cells from the reticuloendothelial system after irradiation with high-energy X-rays.
PURPOSE
To study the uptake capacity of cells from the reticuloendothelial system after irradiation with high-energy X-rays.
METHODS
Eighteen male Wistar rats were distributed in three groups: group A (n = 6): control, unirradiated animals studied alongside animals from group B; group B (n = 6) and group C (n = 6): animals irradiated and studied after 24 and 48 hours, respectively. The rats were anesthetized and placed on a 10 MV linear accelerator. Next, they were irradiated in the abdominal region, with 8 Gy. Twenty-four (groups A and B) and 48 hours later (group C), a colloidal carbon solution (1 mL/kg) was intravenously injected in the tail vein. Fifty minutes later, the spleens and livers were withdrawn and prepared to be studied. Kupffer cells and splenic macrophages containing carbon pigments were counted in an optical microscope. Arithmetic means were calculated for each group and compared among them.
RESULTS
X-rays were associated with a reduced number of Kupffer cells containing colloidal carbon, proliferation and enlargement of biliary ducts, hypoplasia, and hepatocyte necrosis. In the irradiated spleen, the colloidal carbon uptake was concentrated in the marginal zone around the white pulp, with an inexpressive uptake of pigments by macrophages from white and red pulps.
CONCLUSIONS
The X-rays in the rat abdomen are associated with a reduction in the Kupffer cells uptake of colloidal carbon, hepatocyte disorders, bile duct proliferation, and splenic uptake of colloidal carbon concentrated in the marginal zone.
Topics: Rats; Male; Animals; Rats, Wistar; Mononuclear Phagocyte System; Macrophages; Kupffer Cells; Liver; Carbon
PubMed: 37878983
DOI: 10.1590/acb384123 -
Nephron. Clinical Practice 2014Acute kidney injury (AKI) is an increasing medical burden and is independently associated with mortality. AKI is a common comorbidity in the intensive care unit (ICU),... (Review)
Review
Acute kidney injury (AKI) is an increasing medical burden and is independently associated with mortality. AKI is a common comorbidity in the intensive care unit (ICU), with sepsis-associated AKI seen in almost a quarter of all ICU patients. Due to the high mortality seen in these patients, improved therapeutic options are needed. Data from experimental studies in animals support observations in humans that the host immune response to sepsis and trauma contributes to multiorgan failure and the high morbidity and mortality seen in critically ill patients. The spleen, a major component of the reticuloendothelial system, appears to be a key player in the 'cytokine storm' that develops after infection and trauma, and the resultant systemic inflammation is regulated by the autonomic nervous system. Over the past decade, evidence has suggested that controlling the splenic cytokine response improves tissue function and mortality in sepsis and other inflammatory-mediated diseases. One pathway that controls the response of the spleen to sepsis and trauma is the cholinergic anti-inflammatory pathway, and it may provide a key target for therapeutic intervention. Here, we review this concept and highlight the potential use of ultrasound to stimulate the cholinergic anti-inflammatory pathway and reduce systemic inflammation and disease severity.
Topics: Acute Kidney Injury; Adoptive Transfer; Animals; Autonomic Nervous System; CD4-Positive T-Lymphocytes; Cholinergic Fibers; Critical Care; Critical Illness; Cytokines; Humans; Inflammation; Mononuclear Phagocyte System; Neuroimmunomodulation; Norepinephrine; Phagocytes; Receptors, Adrenergic; Sepsis; Spleen; Splenectomy; Systemic Inflammatory Response Syndrome; Tumor Necrosis Factor-alpha; Ultrasonic Therapy; Ultrasonography
PubMed: 25343841
DOI: 10.1159/000363255 -
The Tohoku Journal of Experimental... Feb 1964
Topics: Animals; Antibodies; Bacteriophages; Breast Neoplasms; Carcinoma, Ehrlich Tumor; Colonic Neoplasms; Lung Neoplasms; Mice; Mononuclear Phagocyte System; Neoplasms; Neoplasms, Experimental; Pancreatic Neoplasms; Properdin; Rectal Neoplasms; Research; Skin Transplantation; Stomach Neoplasms; Tetanus Toxoid; Tuberculin Test; Zymosan
PubMed: 14136091
DOI: 10.1620/tjem.82.42 -
Immunological Reviews Nov 2014Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB), is an intracellular pathogen of mononuclear phagocytes. Although M. tuberculosis has... (Review)
Review
Mycobacterium tuberculosis, the bacterium that causes tuberculosis (TB), is an intracellular pathogen of mononuclear phagocytes. Although M. tuberculosis has traditionally been thought to survive and replicate in macrophages, recent work in our laboratory and others has revealed that M. tuberculosis infects multiple subsets of mononuclear phagocytes in vivo and in vitro. In experimental animals, M. tuberculosis infects no fewer than five distinct cell subsets in the lungs, including resident alveolar macrophages and 4 types of cells that recruited to the lungs in response to inflammatory signals: neutrophils, monocytes, interstitial macrophages, and dendritic cells. A characteristic of the adaptive immune response in TB is that it is delayed for several weeks following infection, and we have determined that this delay is due to prolonged residence of the bacteria in lung phagocytes prior to acquisition of the bacteria by dendritic cells. Among the mechanisms used by M. tuberculosis to delay acquisition by dendritic cells is to inhibit apoptosis of alveolar macrophages and neutrophils, which sequester the bacteria and prevent their acquisition by dendritic cells in the early stages of infection. We hypothesize that each infected cell subset makes a distinct contribution to the overall biology of M. tuberculosis and allows the bacteria to evade elimination by T-cell responses and to avoid rapid killing by antimycobacterial drugs.
Topics: Adaptive Immunity; Animals; Cell Differentiation; Cell Movement; Dendritic Cells; Humans; Immunity, Innate; Macrophages; Macrophages, Alveolar; Mononuclear Phagocyte System; Neutrophils; Phenotype; Tuberculosis
PubMed: 25319335
DOI: 10.1111/imr.12217 -
Mucosal Immunology Nov 2008Cells of the mononuclear phagocyte system (MPS) are found in large numbers in every organ of the body, where they contribute to innate and acquired immunity and... (Review)
Review
Cells of the mononuclear phagocyte system (MPS) are found in large numbers in every organ of the body, where they contribute to innate and acquired immunity and homeostasis. This review considers the locations of MPS cells, surface markers that distinguish subsets of monocytes and macrophages, the pathways of MPS differentiation, and the growth factors and transcription factors that guide them. Although the number of MPS sub-populations that can be defined is infinite, the features that unite the MPS remain compelling. Those features clearly include antigen-presenting dendritic cells within the MPS and argue against any basis for separating them from macrophages.
Topics: Animals; Antigens, Differentiation; Biomarkers; Cell Differentiation; Humans; Mononuclear Phagocyte System
PubMed: 19079210
DOI: 10.1038/mi.2008.36