Chemokine Monocyte Research Articles

Monocyte transcriptome signatures of inflammation and enhanced neutrophil recruitment characterize immunopathology in the blood of TB patients

Tuberculosis (TB) is characterized by immunopathology in the blood and monocytes have been shown to be highly sensitive to plasma environment changes in TB patients. Here, we investigated TB plasma effects on ‘reference monocytes’ using RNA sequencing to characterize a potential immunomodulatory role of monocytes in TB. Candidate pathways induced by plasma samples from TB patients (n=99) compared to healthy controls (n=62) were analyzed for changes in signal transduction, phenotype and secreted cytokines by flow cytometry. Finally, potential implications were characterized in blood samples from corresponding patients and controls.Reference monocytes treated with TB plasma showed an enrichment of pathways involved in inflammation and chemotaxis. Inflammatory cytokines were accompanied by enhanced phosphorylation of STAT molecules (i.e., STAT1/3/5) and strong positive correlations were detected for Interleukin (IL)-6 only in TB plasma-treated monocytes. Moreover, monocyte chemokine receptors (i.e., CCR-1, CCR-5) and pro-inflammatory chemokines (i.e., CXCL-1, CXCL-2, CXCL-8, G-CSF, CCL-2) that attract granulocytes and monocytes were significantly higher in TB plasma-treated monocytes. Notably, corresponding clinical samples also showed higher plasma levels for a subset of inflammatory cytokines/chemokines and, in particular, high IL-6 levels correlated positively with accumulation of neutrophil granulocytes in the blood of TB patients. Finally, monocytes from TB patients were characterized by increased chemokine receptor expression, higher proportions of a CCR-2+ subpopulation and aberrant high SOCS3 expression.These results suggest that monocytes may play a significant role in amplifying plasma immunopathology, leading to sustained mobilization and accumulation of neutrophil granulocytes and chronic inflammation in the blood of TB patients.

The MicroRNA miR-223 Constrains Colitis-associated Tumorigenesis by Limiting Myeloid Cell Infiltration and Chemokine Expression.

Aberrant intestinal inflammation plays a critical role in the development of colitis-associated colorectal cancer (CAC), yet the mechanisms controlling tumor development by the myeloid immune compartment are not fully understood. Although altered microRNA expression is observed in CAC, it is also unclear how myeloid-specific microRNAs impact the inflammatory process that underpins the continuum from ulcerative colitis to tumorigenesis. In this study, we report that miR-223 acts to limit myeloid-driven inflammation in the azoxymethane (AOM)-dextran sodium sulfate (DSS) model of CAC in mice. In this model, miR-223-/y mice present with significantly larger tumors with an enhanced proliferative signature. Immunoprofiling showed that miR-223-/y mice have significantly increased colonic myeloid immune infiltrate (neutrophils, monocytes, and macrophages) following AOM-DSS. This was accompanied by an increased inflammatory chemokine and cytokine signature for monocytes and neutrophils. Bone marrow chimera studies demonstrate that myeloid-expressed miR-223 is responsible for the enhanced tumor proliferation and inflammatory response. RNA sequencing identified several pathways that could be contributing to the development of CAC in miR-223-/y mice, including the IL-6/IL-17a cytokine family and STAT3 signaling. Lastly, neutrophil depletion with an anti-GR1 Ab (Ly6G/Ly6C) during the initial phase of the AOM-DSS model reduced the tumor burden in miR-223-/y mice. Collectively, our data indicate that miR-223 is an important regulator of mucosal inflammation and acts to constrain the progression from ulcerative colitis to CAC by limiting myeloid-associated inflammation.

Ethanol-activated microglial exosomes induce MCP1 signaling mediated death of stress-regulatory proopiomelanocortin neurons in the developing hypothalamus

BackgroundMicroglia, a type of resident immune cells within the central nervous system, have been implicated in ethanol-activated neuronal death of the stress regulatory proopiomelanocortin (POMC) neuron-producing β-endorphin peptides in the hypothalamus in a postnatal rat model of fetal alcohol spectrum disorders. We determined if microglial extracellular vesicles (exosomes) are involved in the ethanol-induced neuronal death of the β-endorphin neuron via secreting elevated levels of the chemokine monocyte chemoattractant protein 1 (MCP1), a key regulator of neuroinflammation.MethodsWe employed an in vitro model, consisting of primary culture of hypothalamic microglia prepared from postnatal day 2 (PND2) rat hypothalami and treated with or without 50 mM ethanol for 24 h, and an in vivo animal model in which microglia were obtained from hypothalami of PND6 rats fed daily with 2.5 mg/kg ethanol or control milk formula for five days prior to use. Exosomes were extracted and characterized with nanosight tracking analysis (NTA), transmission electron microscopy and western blot. Chemokine multiplex immunoassay and ELISA were used for quantitative estimation of MCP1 level. Neurotoxic ability of exosome was tested using primary cultures of β-endorphin neurons and employing nucleosome assay and immunocytochemistry. Elevated plus maze, open field and restraint tests were used to assess anxiety-related behaviors.ResultsEthanol elevated MCP1 levels in microglial exosomes both in vitro and in vivo models. Ethanol-activated microglial exosomes when introduced into primary cultures of β-endorphin neurons, increased cellular levels of MCP1 and the chemokine receptor CCR2 related signaling molecules including inflammatory cytokines and apoptotic genes as well as apoptotic death of β-endorphin neurons. These effects of microglial exosomes on β-endorphin neurons were suppressed by a CCR2 antagonist RS504393. Furthermore, RS504393 when injected in postnatal rats prior to feeding with ethanol it reduced alcohol-induced β-endorphin neuronal death in the hypothalamus. RS504393 also suppressed corticosterone response to stress and anxiety-like behaviors in postnatally alcohol-fed rats during adult period.ConclusionThese data suggest that alcohol exposures during the developmental period elevates MCP1 levels in microglial exosomes that promote MCP1/CCR2 signaling to increase the apoptosis of β-endorphin neurons and resulting in hormonal and behavioral stress responses.

NIK Is a Mediator of Inflammation and Intimal Hyperplasia in Endothelial Denudation-Induced Vascular Injury.

Neointimal hyperplasia is the main cause of vascular graft failure in the medium term. NFκB is a key mediator of inflammation that is activated during neointimal hyperplasia following endothelial injury. However, the molecular mechanisms involved in NFκB activation are poorly understood. NFκB may be activated through canonical (transient) and non-canonical (persistent) pathways. NFκB-inducing kinase (NIK, MAP3K14) is the upstream kinase of the non-canonical pathway. We have now explored the impact of NIK deficiency on neointimal hyperplasia following guidewire-induced endothelial cell injury and on local inflammation by comparing NIK activity-deficient alymphoplasia mice (NIKaly/aly) with control wild-type (NIK+/+) mice. Guidewire-induced endothelial cell injury caused neointimal hyperplasia and luminal stenosis and upregulated the local expression of NIK and the NFκB target chemokines monocyte chemoattractant protein-1 (MCP-1/CCL2) and chemokine ligand 5 (RANTES/CCL5). Immunohistochemistry disclosed the infiltration of the media and intima by F4/80 positive macrophages. The intima/media ratio and percentage of stenosis were milder in the NIKaly/aly than in the NIK+/+ mice. Additionally, the gene expression for MCP-1 and RANTES was lower and F4/80+ cell infiltration was milder in the NIKaly/aly than in the NIK+/+ mice. Finally, circulating MCP-1 levels were lower in the NIKaly/aly than in the NIK+/+ mice, reflecting milder systemic inflammation. In conclusion, NIK is a driver of vascular wall inflammation and stenosis following guidewire-induced endothelial cell injury. NIK targeting may be a novel therapeutic approach to limit arterial stenosis following endothelial cell injury.

Profibrotic monocyte-derived alveolar macrophages are expanded in patients with persistent respiratory symptoms and radiographic abnormalities after COVID-19

Monocyte-derived alveolar macrophages drive lung injury and fibrosis in murine models and are associated with pulmonary fibrosis in humans. Monocyte-derived alveolar macrophages have been suggested to develop a phenotype that promotes lung repair as injury resolves. We compared single-cell and cytokine profiling of the alveolar space in a cohort of 35 patients with post-acute sequelae of COVID-19 who had persistent respiratory symptoms and abnormalities on a computed tomography scan of the chest that subsequently improved or progressed. The abundance of monocyte-derived alveolar macrophages, their gene expression programs, and the level of the monocyte chemokine CCL2 in bronchoalveolar lavage fluid positively associated with the severity of radiographic fibrosis. Monocyte-derived alveolar macrophages from patients with resolving or progressive fibrosis expressed the same set of profibrotic genes. Our findings argue against a distinct reparative phenotype in monocyte-derived alveolar macrophages, highlighting their utility as a biomarker of failed lung repair and a potential target for therapy.

STING coordinates resolution of inflammation during wound repair by modulating macrophage trafficking through STAT3.

Efficient cutaneous wound healing requires a coordinated transition between inflammatory phases mediated by dynamic changes in leukocyte subset populations. Here, we identify STING as a key innate immune mediator governing timely resolution of inflammation by regulating macrophage dynamics during skin repair. Using a mouse model, we show STING deficiency caused delayed wound closure associated with abnormal persistence of TNF-α+ leukocytes. This resulted from the impaired macrophage recruitment. STING controlled the trafficking of bone marrow myeloid cells into blood and wounds, intrinsically enhancing macrophage migratory capacity through STAT3 activation. Specifically, STING modulated the production of monocyte chemokines and their receptors CCR2/CCR5 to enable efficient egress and wound infiltration. Consequently, disrupted systemic and local STING-STAT3-chemokine signaling combine to delay macrophage influx. This study elucidates STING as a critical rheostat tuning macrophage responses through STAT3 to orchestrate inflammatory resolution necessary for efficient wound healing. Our findings have broad implications for targeting STING therapeutically in both regenerative medicine and inflammatory disease contexts. STING regulates the macrophage trafficking through STAT3 in wound healing.

DaiTongXiao improves gout nephropathy by inhibiting inflammatory response through the TLR4/MyD88/NF-κB pathway.

Introduction: Gouty nephropathy (GN) arises from factors like excessive purine intake, metabolic disorders or abnormal synthesis, and uric acid hypersaturation in the blood, leading to urate crystal deposition in kidney tissue. DaiTongXiao (DTX) is a remedy used by the Dai people of China. It shows efficacy in lowering uric acid levels and exhibits anti-inflammatory and kidney-protective properties. Methods: A GN rat model was induced using adenine and potassium oxonate. Following DTX administration, various parameters were assessed in urine, serum, and kidney tissue. Western blot analysis evaluated TLR4/MyD88/NF-κB signaling proteins, while immunofluorescence examined NF-κB nuclear expression. Results: DTX treatment improved kidney morphology, increased body weight, and kidney index and enhanced urinary levels of blood urea nitrogen (Bun), 24-h urinary protein, uric acid (UA), and allantoin in GN rats, reducing UA, Bun, creatinine (Cre), cystatin C (CysC), serum amyloid A (SAA), α1-microglobulin (MG), and β2-MG in serum analysis. Renal tissue assessments showed decreased xanthine oxidase (XOD), hydroxyproline (Hyp), α-smooth muscle actin (α-SMA), and collage type Ⅳ (COL-Ⅳ). Kidney damage severity was notably reduced. DTX lowered serum inflammatory factors like interleukin (IL) -18, tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), transforming growth factor-β1 (TGF-β1), and IL-1β in the rat serum, reducing chemokine monocyte chemoattractant protein-1 (MCP-1) and adhesion factor vascular cell adhesion molecule-1(VCAM-1). Western blotting demonstrated the downregulation of TLR4/MyD88/NF-κB pathway proteins, and immunofluorescence revealed reduced NF-κB expression in renal tissue. Discussion: DTX exhibits significant anti-GN effects by modulating TLR4/MyD88/ NF-κB pathway protein expression, reducing inflammatory factor release, and inhibiting GN progression.

Nasal virus infection induces asthma exacerbation through B-cell-dependent recruitment of inflammatory monocytes.

Upper respiratory viral infections (URVIs) are responsible for 80% of asthma exacerbation episodes. However, the underlying mechanisms remain poorly understood. In this study, we used a mouse model of URVI and examined the impact of URVI on asthma phenotypes and the underlying mechanisms. Previously, we have reported that nasal-restricted infection with respiratory syncytial virus (RSV) only produces mild sino-nasal inflammation and mucus production, without causing direct lung infection. However, such nasal-restricted infection dramatically enhanced TH2 and TH17 inflammatory responses in the lungs and increased airway hyperresponsiveness (AHR) in mice with house dust mite (HDM)-induced asthma. Additionally, nasal-restricted infection with RSV recruited Ly6C+ inflammatory monocytes (IMs) into the lungs of mice with and without HDM-induced asthma. The expression of monocyte chemokines, including CCL2 and CCL7, also increased. Interestingly, nasal virus infection-induced AHR was abolished in mice depleted of IMs and in CCR2-/- mice, indicating that the recruited IMs play a key role in nasal virus infection-induced asthma exacerbations in mice. Lastly, we observed that recruitment of Ly6C+ IMs following URVI was abolished in mice lacking B cells and that nasal-restricted infection with RSV increased numbers of CCL2+CCL7+ B cells in the lungs of mice as compared to controls. Taken together, our data have shown that URVI enhances the allergic inflammatory response and AHR through a B cell‒monocyte regulatory axis.

Proinflammatory Activation of Monocytes in Patients with Immunoinflammatory Rheumatic Diseases.

. The objective of this study was to evaluate the proinflammatory activation of circulating monocytes in patients with IRDs. . The study involved 149 participants (53 patients with rheumatoid arthritis (RA), 45patients with systemic lupus erythematosus (SLE), 34 patients with systemic scleroderma (SSc), and 17participants without IRDs) 30 to 65 years old. Basal and lipopolysaccharide (LPS)-stimulated secretion of monocytes was studied in a primary culture of monocytes obtained from blood by immunomagnetic separation. Quantitative assessment of the cytokines tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), as well as the chemokine monocyte chemoattractant protein-1 (MCP-1) was carried out in the culture fluid by ELISA. Proinflammatory activation of monocytes was calculated as the ratio of LPS-stimulated and basal secretions. . It was shown that the basal secretion of all studied cytokines was significantly increased in all groups of patients with IRDs, except for the secretion of IL-1β in the SLE group, compared to the control. LPS-stimulated secretion of TNF-α was increased and MCP-1 was decreased in patients with IRDs compared to the control group; LPS-stimulated IL-1β secretion only in the SSc group significantly differed from the control group. In the RA group, monocyte activation was reduced for all cytokines compared to the control; in the SLE group, for TNF-α and MCP-1; in the SSc group, for MCP-1. . The decrease in proinflammatory activation of monocytes in patients with IRDs is due to a high level of basal secretion of cytokines, which can lead to disruption of the adequate immune response in these diseases and is an important link in the pathogenesis of chronic inflammation.

Neurosteroid [3α,5α]3-hydroxypregnan-20-one inhibition of chemokine monocyte chemoattractant protein-1 in alcohol-preferring rat brain neurons, microglia, and astroglia.

Neuroimmune dysfunction in alcohol use disorder (AUD) is associated with activation of myeloid differentiation primary response 88 (MyD88)-dependent Toll-like receptors (TLR) resulting in overexpression of the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). MCP-1 overexpression in the brain is linked to anxiety, higher alcohol intake, neuronal death, and activation of microglia observed in AUD. The neurosteroid [3α,5α][3-hydroxypregnan-20-one (3α,5α-THP) has been reported as an inhibitor of MyD88-dependent TLR activation and MCP-1 overexpression in mouse and human macrophages and the brain of alcohol-preferring (P) rats. We investigated how 3α,5α-THP regulates MCP-1 expression at the cellular level in P rat nucleus accumbens (NAc) and central amygdala (CeA). We focused on neurons, microglia, and astrocytes, examining the individual voxel density of MCP-1, neuronal marker NeuN, microglial marker IBA1, astrocytic marker GFAP, and their shared voxel density, defined as intersection. Ethanol-naïve male and female P rats were perfused 1 h after IP injections of 15 mg/kg of 3α,5α-THP, or vehicle. The NAc and CeA were imaged using confocal microscopy following double-immunofluorescence staining for MCP-1 with NeuN, IBA1, and GFAP, respectively. MCP-1 intersected with NeuN predominantly and IBA1/GFAP negligibly. 3α,5α-THP reduced MCP-1 expression in NeuN-labeled cells by 38.27 ± 28.09% in male and 56.11 ± 21.46% in female NAc, also 37.99 ± 19.53% in male and 54.96 ± 30.58% in female CeA. In females, 3α,5α-THP reduced the MCP-1 within IBA1 and GFAP-labeled voxels in the NAc and CeA. Conversely, in males, 3α,5α-THP did not significantly alter the MCP-1 within IBA1 in NAc or with GFAP in the CeA. Furthermore, 3α,5α-THP decreased levels of IBA1 in both regions and sexes with no impact on GFAP or NeuN levels. Secondary analysis performed on data normalized to % control values indicated that no significant sex differences were present. These data suggest that 3α,5α-THP inhibits neuronal MCP-1 expression and decreases the proliferation of microglia in P rats. These results increase our understanding of potential mechanisms for 3α,5α-THP modulation of ethanol consumption.

Exposure to polyhexamethyleneguanidine phosphate in early life dampens pulmonary damage compared to adult mice

Polyhexamethyleneguanidine phosphate (PHMG-P) is a biocide of guanidine family that can cause a fatal lung damage if exposed directly to the lungs. No reports exist regarding the toxicity of PHMG-P in neonatal animals. Therefore, this study aimed to determine PHMG-P toxicity in neonatal and 8-week-old mice after they were intranasally instilled with 1.5 mg/kg, 3 mg/kg, and 4.5 mg/kg PHMG-P. PHMG-P lung exposure resulted in more severe pulmonary toxicity in adult mice than in newborn mice. In the high-dose group of newborn mice, a minimal degree of inflammatory cell infiltration and fibrosis in the lung were detected, whereas more severe pathological lesions including granulomatous inflammation, fibrosis, and degeneration of the bronchiolar epithelium were observed in adult mice. At day 4, C–C motif chemokine ligand 2 (CCL2), a potent chemokine for monocytes, was upregulated but recovered to normal levels at day 15 in newborn mice. However, increased CCL2 and IL-6 levels were sustained at day 15 in adult mice. When comparing the differentially expressed genes of newborn and adult mice through RNA-seq analysis, there were expression changes in several genes associated with inflammation in neonates that were similar or different from those in adults. Although no significant lung damage occurred in newborns, growth inhibition was observed which was not reversed until the end of the experiment. Further research is needed to determine how growth inhibition from neonatal exposure to PHMG-P affects adolescent and young adult health.

The protective effects of alamandine on angiotensin II-induced cardiac dysfunction and remodeling in rats

Alamandine (Ala), a relatively recent addition to the renin-angiotensin system (RAS), is a heptapeptide sharing structural similarities with angiotensin-(1-7). This peptide has garnered significant attention due to its distinctive antihypertensive, vasodilatory, and antifibrotic effects. In this study, we sought to determine whether Ala acts as a counter-regulatory agent against angiotensin II-induced cardiac hypertrophy, fibrosis, and inflammation in rats. Male SD rats (n=6 in each group) received a two-week subcutaneous infusion of vehicle (saline), angiotensin II (ANG II, 150 ng/kg/min), or a combination of ANG II and Ala (50 ng/kg/min) via mini osmotic pumps. Left ventricular (LV) function was evaluated through echocardiography. Histological analysis of cardiac hypertrophy and fibrosis was conducted using Hematoxylin Eosin and Trichome-Mason staining, respectively. Compared to the vehicle group, treatment with Ala significantly (*p<0.05) attenuated ANG II-induced cardiac mass (659.27 ± 54.26* vs. 824.48 ± 40.38 mg) with reduced LV thickness and end-diastolic volume. Ala treatment also improved cardiac function, as indicated by reduced global longitudinal strain and myocardial performance index. Histological images revealed that Ala treatment markedly reduced cardiomyocyte area (383.63* ± 7.20 vs 490.59 ± 13.13 μm²) and fibrosis area (5.22* ± 0.93 vs. 9.64 ± 0.36%) in rats treated with ANG II, along with reduced mRNA expression of pro-hypertrophic markers such as brain natriuretic peptide (4.29 ± 0.50* vs 7.53 ± 0.68, fold change) and β-myosin heavy chain (6.11 ± 0.61* vs 10.29 ± 1.02), as well as pro-fibrosis markers collagen 1 (5.72 ± 0.59* vs 10.56 ± 1.69), fibronectin (2.18 ± 0.34* vs 4.69 ± 0.70), and α-smooth muscle actin (2.14 ± 0.42* vs 3.85 ± 0.06), when compared to the rats treated with ANG II alone. Flow cytometry analysis also showed that Ala treatment significantly reduced ANG II-induced immune responses in the heart by reducing immune cell populations including CD4, CD8 T cells, B cells and NK cells, and increasing presence of anti-inflammatory M2 monocytes. Additionally, the mRNA levels of interlukin-6, CD 68, and chemokine monocyte chemoattractant protein-1 were significantly decreased in Ala-treated rats. Furthermore, treatment with Ala reversed ANG II-induced alterations in the mRNA expression of angiotensin-converting enzyme (ACE, 2.05 ± 0.16* vs. 3.08 ± 0.25), angiotensin type 1 receptor (1.45 ± 0.22* vs. 2.56 ± 0.31), and ACE 2 (1.08 ± 0.10** vs. 0.38 ± 0.06) in the LV of the heart. Taken together, these findings demonstrate that alamandine exerts a protective effect against ANG II-induced cardiac dysfunction, hypertrophy, fibrosis, and inflammation, potentially acting as a protective component of the RAS to counteract the adverse effects of ANG II. Alamandine might be a potential therapeutic agent in the treatment of cardiovascular disorders. Supported by NIH grants R01 HL139521 & 155091. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Paricalcitol Has a Potent Anti-Inflammatory Effect in Rat Endothelial Denudation-Induced Intimal Hyperplasia.

Neointimal hyperplasia is the main cause of vascular graft failure in the medium term. Vitamin D receptor activation modulates the biology of vascular smooth muscle cells and has been reported to protect from neointimal hyperplasia following endothelial injury. However, the molecular mechanisms are poorly understood. We have now explored the impact of the selective vitamin D receptor activator, paricalcitol, on neointimal hyperplasia, following guidewire-induced endothelial cell injury in rats, and we have assessed the impact of paricalcitol or vehicle on the expression of key cell stress factors. Guidewire-induced endothelial cell injury caused neointimal hyperplasia and luminal stenosis and upregulated the expression of the growth factor growth/differentiation factor-15 (GDF-15), the cytokine receptor CD74, NFκB-inducing kinase (NIK, an upstream regulator of the proinflammatory transcription factor NFκB) and the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). Immunohistochemistry confirmed the increased expression of the cellular proteins CD74 and NIK. Paricalcitol (administered in doses of 750 ng/kg of body weight, every other day) had a non-significant impact on neointimal hyperplasia and luminal stenosis. However, it significantly decreased GDF-15, CD74, NIK and MCP-1/CCL2 mRNA expression, which in paricalcitol-injured arteries remained within the levels found in control vehicle sham arteries. In conclusion, paricalcitol had a dramatic effect, suppressing the stress response to guidewire-induced endothelial cell injury, despite a limited impact on neointimal hyperplasia and luminal stenosis. This observation identifies novel molecular targets of paricalcitol in the vascular system, whose differential expression cannot be justified as a consequence of improved tissue injury.

Partial recovery of peripheral blood monocyte subsets in head and neck squamous cell carcinoma patients upon radio(chemo)therapy is associated with decreased plasma CXCL11

BackgroundHead and neck squamous cell carcinoma (HNSCC) represents a common and heterogeneous malignancy of the oral cavity, pharynx and larynx. Surgery and radio(chemo)therapy are the standard treatment options and also have great influence on the composition of the tumor microenvironment and immune cell functions. However, the impact of radio(chemo)therapy on the distribution and characteristics of circulating monocyte subsets in HNSCC are not fully understood.MethodsExpression patterns of adhesion molecules and chemokine receptors CD11a (integrin-α L; LFA-1), CD11b (integrin-α M; Mac-1), CD11c (integrin-α X), CX3CR1 (CX3CL1 receptor) and checkpoint molecule PD-L1 (programmed cell death ligand-1) were investigated upon radio(chemo)therapeutic treatment using flow cytometry. Furthermore, comprehensive analysis of plasma cytokines was performed before and after treatment using ELISA measurements.ResultsOur data reveal a partial recovery of circulating monocytes in HNSCC patients upon radio(chemo)therapeutic treatment, with differential effects of the individual therapy regimen. PD-L1 expression on non-classical monocytes significantly correlates with the individual plasma levels of chemokine CXCL11 (C-X-C motif chemokine 11).ConclusionsFurther comprehensive investigations on larger patient cohorts are required to elucidate the meaningfulness of peripheral blood monocyte subsets and chemokine CXCL11 as potential bioliquid indicators in HNSCC with regard to therapy response and the individual immunological situation.

Expression of monocyte chemokine receptors in diabetes after non-surgical periodontal treatment: A pilot study

The aim of this study was to evaluate the effect of non-surgical periodontal treatment in the expression of chemokine receptors, in individuals with Periodontitis, associated or not with Diabetes. Pilot study, which included patients (n = 45) with Periodontitis, associated (n = 25) or not (n = 20) with Diabetes, submitted to the non-surgical periodontal treatment for one month. The expression of chemokine receptors CCR2, CCR5, and CX3CR1 at the mRNA level was evaluated in the peripheral mononuclear cells, as well as the expression of these receptors at the protein level was verified in monocyte subtypes (classical, intermediate, and non-classical monocytes). There was higher expression of CCR2 and CCR5 receptors at the initial visit in the group with Diabetes, with no differences for CX3CR1 (p = 0.002; p = 0.018, and p = 0.896, respectively), without differences after treatment. There was higher expression of CCR2 and CCR5 proteins in the group with Diabetes at the initial visit for classical, intermediate, and nonclassical monocytes, with no differences for CX3CR1 (CCR2: p = 0.004; p = 0.026; p = 0.024; CCR5: 0.045; p = 0.045; p = 0.013; CX3CR1: p = 0.424; p = 0.944; p = 0.392, respectively), without differences after the end of treatment. Concerning each group separately, there were reductions in the expression of CCR2 as well as CCR5 in classical, intermediate, and nonclassical monocytes, and reduction of CX3CR1 in classical monocytes after treatment in the group with Diabetes (p = 0.003; p = 0.006; p = 0.039; p = 0.007; p = 0.006; p = 0.004; p = 0.019, respectively), without differences in the group without Diabetes. The expression of the chemokine receptors CCR2 and CCR5, in patients with Periodontitis associated with Diabetes, is favorably modified after the end of the non-surgical periodontal treatment.

B cells mediate lung ischemia/reperfusion injury by recruiting classical monocytes via synergistic B cell receptor/TLR4 signaling.

Ischemia/reperfusion injury-mediated (IRI-mediated) primary graft dysfunction (PGD) adversely affects both short- and long-term outcomes after lung transplantation, a procedure that remains the only treatment option for patients suffering from end-stage respiratory failure. While B cells are known to regulate adaptive immune responses, their role in lung IRI is not well understood. Here, we demonstrated by intravital imaging that B cells are rapidly recruited to injured lungs, where they extravasate into the parenchyma. Using hilar clamping and transplant models, we observed that lung-infiltrating B cells produce the monocyte chemokine CCL7 in a TLR4-TRIF-dependent fashion, a critical step contributing to classical monocyte (CM) recruitment and subsequent neutrophil extravasation, resulting in worse lung function. We found that synergistic BCR-TLR4 activation on B cells is required for the recruitment of CMs to the injured lung. Finally, we corroborated our findings in reperfused human lungs, in which we observed a correlation between B cell infiltration and CM recruitment after transplantation. This study describes a role for B cells as critical orchestrators of lung IRI. As B cells can be depleted with currently available agents, our study provides a rationale for clinical trials investigating B cell-targeting therapies.

Assessment of Monocyte Chemoattractant Protein -1 and Fertility Hormones in Iraqi Women with Polycystic Ovarian Syndrome

Polycystic ovarian syndrome (PCOS) is a well-known endocrinopathy and one of the most frequent endocrine-reproductive-metabolic syndromes in women, which can result in reduced fertility. While the actual cause is unknown, PCOS is regarded as a complicated genetic characteristic with a great degree of variability. Moreover, hormones and immune cells, including both innate and acquired immune cells, are thought to interact in PCOS. Chronic low-grade inflammation raises the risk of autoimmune disease. The study's purpose is to investigate the chemokine monocyte chemoattractant protein-1 (MCP-1) and fertility hormones in samples of women patients with polycystic ovary syndrome (PCOS) in the City of Medicine. Sixty PCOS women comprise 30 healthy control women; their average age was 20–40 years, and their weight ranged from 60 to 100 kg. The results showed an increase in the level of MCP1 in PCOS patients, but this increase was not significant (P<0.05), which was not influenced by BMI or fertility hormones. As well as elevated fertility hormones, this study, when compared to controls as well as patients with PCOS, showed a significant increase in the level of testosterone (14.63 ±2.30 nmol/L) while in control women (0.627 ±0.04), LH hormone in patients and control group (6.54 ±0.51 mIU/mL), and 2.93 ±0.18, respectively. Prolactin hormone was increased in PCOS patients (16.27 ±1.25 ng/mL) when compared to the control group \ (12.85 ±0.62). There was no significant difference in FSH hormone in women with PCOS (5.27 ±0.28 mIU/mL) compared with the control group (5.59 ±0.18).

Monocyte chemoattractant protein-1 and cyclooxygenase enzymes in rats treated with drugs of abuse

The CC chemokine monocyte chemoattractant protein (MCP)-1/CCL2 and cyclo-oxygenase-2 enzyme are potent mediators of neuroinflammation. We studied the effect of treatment with Cannabis sativaresin extract and/or tramadol, two common drugs of abuse on the level of MCP-1 in brain and serum of rats. In addition, serum levels of cyclo-oxygenase 1 (COX-1) and cyclo-oxygenase 2 (COX-2) enzymes in rats given cannabis werealso determined. Cannabis sativaresin at 5, 10 or 20 mg/kg (expressed as delta-9-tetrahydrocannabinol), tramadol at 5, 10 or 20 mg/kg or tramadol at 10 mg/kg combined with cannabis at 5-20 mg/kg were given once a day, subcutaneously, for six weeks. Resultsshowed that, as compared to corresponding controls, Cannabis sativa resin produced a significant increase in MCP-1 increased inbrain tissue (29.8-56.4%) and serum (14.8-31.0%). MCP-1 showed also significant increments in brain (34.6%) and serum (22.1%) by 20 mg/kg tramadol. After the concomitant treatment with both cannabis and tramadol, MCP-1 increased in brainby 88.5-145.7%and in serum by 32.6-64.8%. Moreover, cannabis given at 20 mg/kg significantly increasedserum COX-1 and COX-2 by 362% and 58.8% compared to corresponding control values. The histopathological study of the striatum of cannabis-treated animals revealed the presence of apoptotic cells and pyknotic nuclei and congestion of blood vessels. The striatum from animals given tramadol showed neuronal perinuclear cytoplasmic vacuolations and apoptotic cells. Moreover, the combined administration of both cannabis and tramadol resulted in neuronal necrosis, vacuolation, apoptosis and pyknosis. Collectively, these results indicate that treatment with cannabis resin and/or tramadol is associated with a proinflammatory response that involves MCP-1 and cyclooxygenases and which could result in the development of brain injury.

CCR2 antagonist attenuates calcium oxalate-induced kidney oxidative stress and inflammation by regulating macrophage activation.

C-C chemokine receptor type 2 (CCR2) is a monocyte chemokine associated with oxidative stress and inflammation. Kidney stones (KS) are composed of calcium oxalate (CaOx), which trigger renal oxidative stress and inflammatory. This study aims to evaluate the effects of CCR2 on KS in vivo and in vitro. Eight-week-old male C57BL/6J mice were intraperitoneally injected with glyoxylate (GOX) daily to establish a KS model, and along with CCR2 antagonist (INCB3344) treatment on days 2, 4, and 6. The results showed that CCR2 antagonist reduced renal injury markers (blood urea nitrogen and serum creatinine), alleviated renal tubular injury and CaOx crystal deposition. CCR2 antagonist also decreased CCR2 expression induced by GOX treatment and increased Nrf2 expression. GOX treatment promoted malondialdehyde (MDA) production, decreased glutathione (GSH) content, and inhibited catalase (CAT) and superoxide dismutase (SOD) activity, however, CCR2 antagonist attenuated the above effects of GOX. CCR2 antagonist had inhibitory effects on GOX-induced inflammatory cytokine expression (IL1B, IL6 and MCP1), and inhibited apoptosis by increasing Bcl-2 expression and decreasing Bax and cleaved-caspase 3 expression. In vitro experiments were performed by co-culture model of CaOx-induced damaged HK-2 cells and macrophage-like THP-1 cells. CCR2 antagonist inhibited CaOx-induced THP-1 cell M1 polarization by decreasing the TNF-α, IL6 and iNOS levels, and further alleviated CaOx-induced oxidative stress damage, inflammatory response and apoptosis of HK-2 cells. The study suggests that CCR2 antagonist may be resistant to CaOx crystals-induced oxidative stress and inflammation by inhibiting macrophage M1 polarization.

Roles of macrophages in lupus nephritis.

LN is a serious complication of systemic lupus erythematosus (SLE), affecting up to 60% of patients with SLE and may lead to end-stage renal disease (ESRD). Macrophages play multifaceted roles in the pathogenesis of LN, including clearance of immune complexes, antigen presentation, regulation of inflammation, and tissue repair. Macrophages are abundant in the glomeruli and tubulointerstitium of LN patients and are positively correlated with serum creatinine levels and the severity of renal pathology. It has been shown that the infiltration of macrophages is closely associated with several clinical indicators, such as serum creatinine and complement C3 levels, anti-dsDNA antibody titers, Austin score, interstitial fibrosis and renal tubular atrophy. Moreover, cytokines expressed by macrophages were upregulated at LN onset and downregulated after remission, suggesting that macrophages may serve as markers of LN pathogenesis and remission. Therapies targeting macrophages have been shown to alleviate LN. There are two main types of macrophages in the kidney: kidney-resident macrophages (KRMs) and monocyte-derived macrophages (MDMs). KRMs and MDMs play different pathological roles in LN, with KRMs promoting leukocyte recruitment at sites of inflammation by expressing monocyte chemokines, while MDMs may exacerbate autoimmune responses by presenting immune complex antigens. Macrophages exhibit high plasticity and can differentiate into various phenotypes in response to distinct environmental stimuli. M1 (proinflammatory) macrophages are linked to the progression of active SLE, whereas the M2 (anti-inflammatory) phenotype is observed during the remission phase of LN. The polarization of macrophages in LN can be manipulated through multiple pathways, such as the modulation of signaling cascades including TLR 2/1, S1P, ERS, metabolic reprogramming, and HMGB1. This paper provides a comprehensive overview of the role of macrophages in the progression of lupus nephritis (LN), and elucidates how these cells and their secretory products function as indicators and therapeutic targets for the disease in the context of diagnosis and treatment of LN.