Macrophages are heterogeneous and their phenotype and functions are regulated by the surrounding micro-environment. Macrophages commonly exist in two distinct subsets: 1) Classically activated or M1 macrophages, which are pro-inflammatory and polarized by lipopolysaccharide (LPS) either alone or in association with Th1 cytokines such as IFN-γ, GM-CSF, and produce pro-inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, IL-12, IL-23, and TNF-α; and 2) Alternatively activated or M2 macrophages, which are anti-inflammatory and immunoregulatory and polarized by Th2 cytokines such as IL-4 and IL-13 and produce anti-inflammatory cytokines such as IL-10 and TGF-β. M1 and M2 macrophages have different functions and transcriptional profiles. They have unique abilities by destroying pathogens or repair the inflammation-associated injury. It is known that M1/M2 macrophage balance polarization governs the fate of an organ in inflammation or injury. When the infection or inflammation is severe enough to affect an organ, macrophages first exhibit the M1 phenotype to release TNF-α, IL-1β, IL-12, and IL-23 against the stimulus. But, if M1 phase continues, it can cause tissue damage. Therefore, M2 macrophages secrete high amounts of IL-10 and TGF-β to suppress the inflammation, contribute to tissue repair, remodeling, vasculogenesis, and retain homeostasis. In this review, we first discuss the basic biology of macrophages including origin, differentiation and activation, tissue distribution, plasticity and polarization, migration, antigen presentation capacity, cytokine and chemokine production, metabolism, and involvement of microRNAs in macrophage polarization and function. Secondly, we discuss the protective and pathogenic role of the macrophage subsets in normal and pathological pregnancy, anti-microbial defense, anti-tumor immunity, metabolic disease and obesity, asthma and allergy, atherosclerosis, fibrosis, wound healing, and autoimmunity.
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Background: Studies suggest that cytokines are involved in the development of both inflammatory disorders and vascular diseases. Objective: The changes in transforming growth factor β (TGFβ), interleukin 6 (IL6), tumor necrosis factor α (TNFα), and interferon γ (IFNγ) with the progression of the thromboangiitis obliterans (TAO) symptomswereinvestigated in this research. Methods: This study included 80 patients with TAO, who were selected from the Vascular and Endovascular Research Center in Alavi Hospital between 2012 and 2016. They were then categorized into three groups: mild (migratory thrombophlebitis, cold sensitivity or Raynaud's phenomenon, and skin discoloration), moderate (chronic ulcers, claudication, and burning pain of the feet at night), and severe (pain at rest and spontaneous gangrene) symptoms. The serum levels of TGFβ, IL6, TNFα, and IFNγwere determinedby the ELISA method and compared among the groups. Results: The first three predominant symptoms were pulse disorder (n = 76, 95.00%), cold intolerance (n = 61, 76.25%), and claudication (n = 59, 73.75%). A comparison of the analysis of covariance (ANCOVA) revealed that both TGFβ and IL6 were dysregulatedas the severity of the symptoms increased from the moderate to the severe stages; however, such changes were not significant(p > 0.05). In the multiple logistic regression model, increased TNFαlevelswere seen in the presence of the moderatesymptoms as compared to the severe ones (p < 0.05). Conclusion: It could be concluded that TNFα, as part of the defining cytokine-production profile of Thelper cells, can be significantly involved in the progression of TAO from the moderate to the severe stages.
Background: Autoimmunity causes the loss of normal immune homeostasis and involves the presence of autoantibodies and inflammation. Thromboangiitis obliterans or Buerger's disease (BD) refers to a type of vascular obstructive syndrome, with tobacco exposure accounting for disease formation and progression. However, the current understanding of autoimmunity is unclear in the context of BD, and the scientific findings are not enough to support autoimmune mechanisms. This study was aimed at investigating autoimmunity factors in patients with BD. Methods: Clinical and experimental examinations were performed on 80 patients with BD. The diagnostic work-up for autoimmunity was composed of IgM rheumatoid factor (RF), anti-nuclear antibodies (ANA), The erythrocyte sedimentation rate (ESR), anti-cyclic citrullinated peptide (CCP) antibodies, Antiphospholipid antibodies (APA), Anti-cardiolipin antibodies (ACLA), anti-double-stranded DNA (ds-DNA), and extractable nuclear antigen (ENA) profile. Immunomarkers were detected using the quantitative enzyme-linked immunosorbent assay (ELISA). Results: Raynaud's phenomenon (84.93%), cold sensitivity (76.25%), and claudication (73.75%) were the most common symptoms in the BD patients. Also, 64.29% represented with high ANA levels and positive RF, while 42.11% were found with increased ANA and ESR levels. The ANA/RF positive BD patients had ESR> 15 mm/hr and a high prevalence of cold sensitivity, claudication, and Raynaud's phenomenon (p> 0.05). Conclusions: There is a possibility of a non-specific autoimmune disposition among BD patients. RF and ANA could be considered for predicting disease progression.
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