Higher expression of monocyte chemotactic protein 1 in mild COVID-19 patients might be correlated with inhibition of Type I IFN signaling.

BACKGROUND: Chemokine levels in severe coronavirus disease 2019 (COVID-19) patients have been shown to be markedly elevated. But the role of chemokines in mild COVID-19 has not yet been established. According to the epidemiological statistics, most of the COVID-19 cases in Shiyan City, China, have been mild. The purpose of this study was to evaluate the level of chemokines in mild COVID-19 patients and explore the correlation between chemokines and host immune response. METHODS: In this study, we used an enzyme-linked immunosorbent assay to detect serum levels of chemokines in COVID-19 patients in Shiyan City. Expression of chemokine receptors and of other signaling molecules was measured by real-time polymerase chain reaction. RESULTS: We first demonstrated that COVID-19 patients, both sever and mild cases, are characterized by higher level of chemokines. Specifically, monocyte chemotactic protein 1 (MCP-1) is expressed at higher levels both in severe and mild cases of COVID-19. The receptor of MCP-1, C-C chemokine receptor type 2, was expressed at higher levels in mild COVID-19 patients. Finally, we observed a significant negative correlation between expression levels of interferon (IFN) regulatory factor 3 (IRF3) and serum levels of MCP-1 in mild COVID-19 patients. CONCLUSION: Higher expression of MCP-1 in mild COVID-19 patients might be correlated with inhibition of IFN signaling. The finding adds to our understanding of the immunopathological mechanisms of severe acute respiratory syndrome coronavirus 2 infection and provides potential therapeutic targets and strategies.

HTLV-1-host interactions facilitate the manifestations of cardiovascular disease.

Atherosclerosis is a multifactorial life-threatening disease which an epidemiologic study in Northeastern Iran showed its association with HTLV-1 infection. Therefore, a cross-sectional study of 39 newly diagnosed subjects with angiography test in three groups including 14 coronary artery disease+HTLV-1+ (CAD+HTLV-1+), 8 CAD-HTLV-1+, and 17 CAD+HTLV-1- patients and 11 healthy subjects (CAD-HTLV-1-) were conducted. In the present study, Tax and proviral load (PVL) as HTLV-1 virulence factors, along with host chemokine receptor 1 (CCR1), and CCR2 were investigated. Real-time PCR TaqMan method was carried out for PVL measurement and HTLV-1-Tax, CCR1, and CCR2 expressions in peripheral blood mononuclear cells (PBMCs). Furthermore, the main risk factors, lipid profile, and complete blood count (CBC) were assessed. Expression of CCR1 in CAD+HTLV-1+ group was higher than CAD-HTLV-1+ (P = 0.01) and healthy subjects (P = 0.02). Expression of CCR1 in CAD+HTLV-1+ was higher in comparison with CAD+HTLV-1-group but did not meet 95% CI (P = 0.02), but meaningful at 91% CI. In addition, expression of CCR2 in CAD+HTLV-1+ subjects was higher than CAD-HTLV-1+ and CAD+HTLV-1- (P = 0.001, P = 0.005, respectively). In CAD+HTLV-1- subjects, CCR2 was higher than CAD-HTLV-1+ (P = 0.03). The mean PVL in CAD+HTLV-1+ group is more than CAD-HTLV-1+ (P = 0.041). In HTLV-1+ patients Tax had a positive correlation with cholesterol (R = 0.59, P = 0.01), LDL (R = 0.79, P = 0.004) and a negative correlation with HDL (R = -0.47, P = 0.04). These correlations were stronger in CAD+HTLV-1+. Findings showed that HTLV-1 could alter the expression of CCR2 and, less effect, on CCR1. Moreover, the strong correlation between CCR2 and HTLV-1-Tax with cholesterol, LDL and HDL showed that Tax as the main HTLV-1 virulence factor in cytokine deregulation might be had indirect effects on cholesterol, LDL, and HDL levels.

Prognostic significance of monocyte chemoattractant protein-1 and CC chemokine receptor 2 in diffuse large B cell lymphoma.

Aberrant monocyte chemoattractant protein-1 (MCP-1) and CC chemokine receptor 2 (CCR2) expression in malignant tissues have been reported; however, their role in hematological malignancies prognosis remains little known. The aim of this study was to investigate the prognostic value of MCP-1 and CCR2 expression in patients with diffuse large B cell lymphoma (DLBCL). The study included 221 patients with DLBCL. MCP-1 and CCR2 expression was analyzed by immunohistochemical staining and its correlations with clinicopathologic features and prognosis were evaluated. High expression of MCP-1 or CCR2 was correlated with clinicopathological characteristics, and an adverse prognostic factor for overall survival (OS) and progression-free survival (PFS) of DLBCL patients. Also, significant positive correlation between MCP-1 and CCR2 expression was revealed (r = 0.545, P < 0.001). Patients with high MCP-1 or high CCR2 expression had significantly poorer OS and PFS than those with low MCP-1 or low CCR2 expression (OS: P < 0.001, P < 0.001; PFS: P < 0.001, P < 0.001), respectively, even in the rituximab era, and MCP-1 or CCR2 expression could further identify high-risk patients otherwise classified as low/intermediate risk by the International Prognostic Index (IPI) alone. Furthermore, incorporation of MCP-1 or CCR2 expression into the IPI score could improve prognostic value for OS. This is the first report describing the clinicopathological features and survival outcome according to expression of MCP-1 and CCR2 in DLBCL.

Chemokine CC-motif ligand 2 participates in platelet function and arterial thrombosis by regulating PKCα-P38MAPK-HSP27 pathway.

BACKGROUND: Studies indicate that chemokine CC-motif ligand 2 (CCL2) is involved in inflammation and atherosclerosis. However, the roles and mechanisms of CCL2 on platelet function and arterial thrombosis are unknown. METHODS: The expressions of CCL2 or CCR2 in the plasma, platelets and coronary thrombus of ST-elevated myocardial infarction (STEMI) patients were examined by ELISA, Western blot, immunohistochemistry and immunofluorescence. The roles of CCL2 on platelet aggregation, activation and secretion were examined by light transmission aggregometry, flow cytometry and ELISA. RESULTS: The expressions of CCL2 or CCR2 in the plasma or platelets of STEMI patients with platelet high response were higher than those with platelet normal response; In vitro, exogenous recombinant human CCL2 markedly increased platelet aggregation, activation and granule secretion, which were abolished by CCL2 neutralizing antibody or CCR2 inhibiter. CCL2 increased the phosphorylation levels of PKCα (Thr638), P38MAPK (Thr180/Tyr182) and HSP27 (S78/S82) in human platelets, which were abrogated by PKCα inhibitor (RO 318220) or P38MAPK inhibitor (SB 203580). RO 318220 or SB 203580 diminished CCL2-induced platelet function. In CCL2-/- mice, platelet aggregation and secretion were attenuated; the phosphorylation of PKCα, P38MAPK and HSP27 were decreased. In a carotid arterial thrombus mouse model, CCL2-/- mice displayed a significantly extended carotid artery occlusion time compared with wild type. CONCLUSIONS: CCL2 played important roles in regulating platelet function and arterial thrombosis through the PKCα-P38MAPK-HSP27 pathway, which might provide theoretical basis for searching new antiplatelet drugs and the treatment for cardiovascular diseases.

Monocyte activation is elevated in women with knee-osteoarthritis and associated with inflammation, BMI and pain.

OBJECTIVE: Monocytes contribute to synovitis and disease pathogenesis in osteoarthritis (OA). Low-grade inflammation occurs in OA and correlates with disease severity and progression. Since monocyte development and function is altered by systemic inflammation, we analyzed monocyte numbers and function between individuals with knee OA and healthy age- and sex-matched controls. DESIGN: We analyzed markers of soluble and cellular inflammation in peripheral blood of women with knee OA and compared them to healthy age- and sex-matched controls. Soluble inflammatory mediators (TNF, IL-6, IL-10 and CRP) in the serum were measured by high-sensitivity ELISA. Leukocyte numbers, surface expression of monocyte activation markers, and monocyte production of pro-inflammatory mediators (TNF and IL-1ß) following stimulation were measured by flow cytometry. RESULTS: Women with knee OA (n = 15) had elevated levels of serum c-reactive protein (CRP) and a lower proportion of circulating monocytes. Monocytes from OA participants had elevated expression of the activation markers CD16, CCR2, and HLA-DR and induced greater production of tumor necrosis factor (TNF) and IL-1ß compared to healthy controls. Higher serum TNF and BMI were correlated with increased monocyte expression of CCR2. Additionally monocyte CCR2 expression and serum TNF were correlated with worse pain on a validated questionnaire. CONCLUSIONS: Our findings suggest monocytes are activated prior to their entry into the synovium. Modulating systemic inflammation and monocyte recruitment to the synovium could be of therapeutic benefit.

Human Blood Monocyte Subsets: A New Gating Strategy Defined Using Cell Surface Markers Identified by Mass Cytometry.

OBJECTIVE: Human monocyte subsets are defined as classical (CD14++CD16-), intermediate (CD14++CD16+), and nonclassical (CD14+CD16+). Alterations in monocyte subset frequencies are associated with clinical outcomes, including cardiovascular disease, in which circulating intermediate monocytes independently predict cardiovascular events. However, delineating mechanisms of monocyte function is hampered by inconsistent results among studies. APPROACH AND RESULTS: We use cytometry by time-of-flight mass cytometry to profile human monocytes using a panel of 36 cell surface markers. Using the dimensionality reduction approach visual interactive stochastic neighbor embedding (viSNE), we define monocytes by incorporating all cell surface markers simultaneously. Using viSNE, we find that although classical monocytes are defined with high purity using CD14 and CD16, intermediate and nonclassical monocytes defined using CD14 and CD16 alone are frequently contaminated, with average intermediate and nonclassical monocyte purity of ≈86.0% and 87.2%, respectively. To improve the monocyte purity, we devised a new gating scheme that takes advantage of the shared coexpression of cell surface markers on each subset. In addition to CD14 and CD16, CCR2, CD36, HLA-DR, and CD11c are the most informative markers that discriminate among the 3 monocyte populations. Using these additional markers as filters, our revised gating scheme increases the purity of both intermediate and nonclassical monocyte subsets to 98.8% and 99.1%, respectively. We demonstrate the use of this new gating scheme using conventional flow cytometry of peripheral blood mononuclear cells from subjects with cardiovascular disease. CONCLUSIONS: Using cytometry by time-of-flight mass cytometry, we have identified a small panel of surface markers that can significantly improve monocyte subset identification and purity in flow cytometry. Such a revised gating scheme will be useful for clinical studies of monocyte function in human cardiovascular disease.

Altered proportion of CCR2+ and CX3CR1+ circulating monocytes in neovascular age-related macular degeneration and polypoidal choroidal vasculopathy.

BACKGROUND: We investigated the expression of chemokine receptors CCR2 (C-C chemokine receptor) 2 and CX3CR1 (C-X3-C receptor 1) on circulating monocyte subsets in patients with neovascular age-related macular degeneration (AMD) and patients with polypoidal choroidal vasculopathy (PCV). METHODS: We recruited patients with neovascular AMD, patients with PCV and age-matched healthy controls for this prospective case-control study. All participants underwent comprehensive clinical examination and imaging. Freshly sampled venous blood was prepared for flow cytometry, where we determined the proportion of CCR2+ - and CX3CR1+ -positive cells in monocyte subsets identified using monocyte identification and subgrouping surface markers CD14, CD16 and HLA-DR. RESULTS: Patients with neovascular AMD had significantly increased proportion of CCR2+ and CX3CR1+ non-classical monocytes. PCV type 1 was associated with significantly increased CCR2+ and CX3CR1+ in all monocyte subsets when compared to PCV type 2. CONCLUSIONS: Neovascular AMD is associated with increased expression of angiogenesis-associated chemokine receptors in the pro-inflammatory non-classical monocytes. PCV differs from neovascular AMD immunologically and show immunological heterogeneity across angiographic subtypes.

Association of hydrogen sulfide with alterations of monocyte chemokine receptors, CCR2 and CX3CR1 in patients with coronary artery disease.

OBJECTIVES: Recent data in human and mice suggest that monocyte chemokine receptors CX3CR1 and CCR2 are involved in the pathogenesis of atherosclerosis. Our previous study showed that hydrogen sulfide, a novel gaseous mediator hampered the progression of atherosclerosis in fat-fed apoE(-/-) mice with downregulating CX3CR1 and CX3CL1 expressions. However, there is a paucity of information regarding the clinical association between endogenous H2S metabolism and alterations of monocyte chemokine receptors in patients with cardiovascular disease. Therefore, in this study, we investigated circulating monocyte heterogeneity with differential expressions of CCR2 and CX3CR1 and its relevance to plasma H2S level in patients with coronary artery disease (CAD). METHODS: Sixty-three CAD patients with acute coronary syndrome (ACS, n = 46) or stable angina pectoris (SAP, n = 17) undergoing either percutaneous coronary intervention or coronary angiography and eleven non-CAD patients were enrolled in the study. Plasma levels of H2S as well as chemokines (CCL2 and CX3CL1) and expressions of CCR2 and CX3CR1 on peripheral monocytes were measured. RESULTS: It was found that plasma H2S level was significantly reduced, whereas plasma CCL2 and CX3CL1 levels were substantially elevated in patients with ACS, as compared with patients with SAP or non-CAD patients. Furthermore, patients with ACS had significantly higher proportion of CD14(+)CCR2(+)CX3CR1(+) and CD14(+)CCR2(-)CX3CR1(+) monocytes but lower percentage of CD14(+)CCR2(+)CX3CR1(-) monocytes than SAP or non-CAD patients did. Lastly, plasma H2S level showed a significantly negative correlation with the proportion of CD14(+)CCR2(+)CX3CR1(+) monocytes, but not other monocyte subsets. CONCLUSIONS: These data indicate that decreased endogenous H2S production may predispose stable CAD patients to rupture of vulnerable plaque and thus to ACS, probably in relation to circulating monocyte phenotypic transformation with differential expressions of CCR2 and CX3CR1.

TLR2-dependent pathway of heterologous down-modulation for the CC chemokine receptors 1, 2, and 5 in human blood monocytes.

During innate immune responses, the inflammatory CC chemokine receptors CCR1, CCR2, and CCR5 mediate the recruitment of blood monocytes to infected tissues by promoting cell migration in response to chemokines CCL2-5. Toll-like receptors also play an essential role, allowing pathogen recognition by the recruited monocytes. Here, we demonstrate that Toll-like receptor 2 (TLR2) stimulation by lipoteichoic acid (LTA) from Staphylococcus aureus leads to gradual down-modulation of CCR1, CCR2, and CCR5 from the plasma membrane of human blood-isolated monocytes and inhibits chemotaxis. Interestingly, LTA does not promote rapid desensitization of chemokine-mediated calcium responses. We found that the TLR2 crosstalk with chemokine receptors is not dependent on the Toll/interleukin-1 receptor domain-containing adaptor protein, but instead involves phospholipase C, the small G protein Rac1, and is phorbol ester sensitive. Activation of this pathway by LTA lead to ß-arrestin-mediated endocytosis of Ser349-phosphorylated CCR5 into recycling endosomes, as does CCL5 treatment. However, LTA-induced internalization of CCR5 is a slower process associated with phospholipase C-mediated and phorbol ester-sensitive phosphorylation. Overall, our data indicate that TLR2 negatively regulates CCR1, CCR2, and CCR5 on human blood monocytes by activating the machinery used to support chemokine-dependent down-modulation and provide a molecular mechanism for inhibiting monocyte migration after pathogen recognition.

Essential role of CCR2 in neutrophil tissue infiltration and multiple organ dysfunction in sepsis.

RATIONALE: Sepsis is defined as a systemic inflammatory response to infection, which in its severe form is associated with multiple organ dysfunction syndrome (MODS). The precise mechanisms by which MODS develops remain unclear. Neutrophils have a pivotal role in the defense against infections; however, overwhelming activation of neutrophils is known to elicit tissue damage. OBJECTIVES: We investigated the role of the chemokine receptor CCR2 in driving neutrophil infiltration and eliciting tissue damage in remote organs during sepsis. METHODS: Sepsis was induced in wild-type mice treated with CCR2 antagonist (RS504393) or CCR2(-/-) mice by cecal ligation and puncture (CLP) model. Neutrophil infiltration into the organs was measured by myeloperoxidase activity and fluorescence-activated cell sorter. CCR2 expression and chemotaxis were determined in neutrophils stimulated with Toll-like receptor agonists or isolated from septic mice and patients. MEASUREMENTS AND MAIN RESULTS: CCR2 expression and responsiveness to its ligands was induced in circulating neutrophils during CLP-induced sepsis by a mechanism dependent on Toll-like receptor/nuclear factor-κB pathway. Genetic or pharmacologic inhibition of CCR2 protected mice from CLP-induced mortality. This protection was associated with lower infiltration of neutrophils into the lungs, heart, and kidneys and reduced serum biochemical indicators of organ injury and dysfunction. Importantly, neutrophils from septic patients express high levels of CCR2, and the severity of patient illness correlated positively with increasing neutrophil chemotaxis to CCR2 ligands. CONCLUSIONS: Collectively, these data identify CCR2 as a key receptor that drives the inappropriate infiltration of neutrophils into remote organs during sepsis. Therefore, CCR2 blockade is a novel potential therapeutic target for treatment of sepsis-induced MODS.

No difference in markers of adipose tissue inflammation between overweight women with polycystic ovary syndrome and weight-matched controls.

UNLABELLED: BACKGROUND; Previous studies have indicated that peripheral circulating markers of inflammation are elevated in women with polycystic ovary syndrome (PCOS), but thus far no studies concerning markers of inflammation in adipose tissue have been published. The aim of the study was to investigate whether patients with PCOS display increased expression of inflammatory markers in adipose tissue. METHODS: Twenty overweight patients with PCOS, 10 lean patients with PCOS and 20 overweight controls had subcutaneous fat biopsies and blood samples taken. Adipose tissue levels of mRNA of inflammatory markers were determined by use of real-time PCR. RESULTS: Overweight patients with PCOS had higher relative adipose tissue chemokine ligand 2 (P < 0.01), and its cognate receptor (P < 0.05), tumour necrosis factor-α (P < 0.001), interleukin (IL)-10 (P < 0.001) and IL-18 (P < 0.001) and the monocyte/macrophage markers CD14 (P < 0.01) and CD163 (P < 0.01) mRNA levels compared with lean women with PCOS. There were no differences between overweight patients with PCOS and overweight control subjects in this respect. Within the PCOS group, markers of adipose tissue inflammation correlated significantly with obesity-related metabolic disturbances, but when data were adjusted for age and BMI, most correlations were lost. CONCLUSIONS: Overweight, rather than the PCOS diagnosis per se, appears to be the main explanatory variable for elevated adipose tissue inflammation in patients with PCOS.

Cellular and molecular changes associated with inhibitory effect of pioglitazone on neointimal growth in patients with type 2 diabetes after zotarolimus-eluting stent implantation.

OBJECTIVE: To investigate the mechanistic basis underlying antirestenosis and the antiatherogenic effect of pioglitazone in patients with type 2 diabetes mellitus who were undergoing zotarolimus-eluting stent implantation. METHODS AND RESULTS: Recent studies highlight the beneficial effect of pioglitazone in attenuating neointimal growth after stent implantation. Patients with coronary artery diseases were randomly assigned to pioglitazone (n=47) or placebo (n=47) after stent implantation. Pioglitazone significantly reduced neointimal hyperplasia within the stented lesion and attenuated total plaque burden in the in-segment regions of the stent, as assessed by intravascular ultrasonography at the 8-month follow-up. These changes were preceded by reduced circulating natural killer (NK) cells, diminished interleukin 6 and monocyte chemoattractant protein-1 levels, and downregulation of chemokine receptor 2 at 2 days after stent implantation; and an elevated interleukin 10 level at 10 days after implantation. Furthermore, the proliferation and migration of vascular smooth muscle cells were inhibited in the presence of pioglitazone-treated patient serum, demonstrating that the antiproliferative effects of pioglitazone occurred concurrently with its antiinflammatory action. CONCLUSIONS: Our data present early cellular and immunologic changes by pioglitazone that might have been associated with antirestenotic and antiatherogenic effects in diabetic patients. Inhibiting proinflammatory responses while promoting antiinflammatory circuits, together with an antiproliferative action, may, in part, account for the antirestenotic effect of pioglitazone by altering vascular remodeling processes in the early phase.

Discovery of ((1S,3R)-1-isopropyl-3-((3S,4S)-3-methoxy-tetrahydro-2H-pyran-4-ylamino)cyclopentyl)(4-(5-(trifluoromethyl)pyridazin-3-yl)piperazin-1-yl)methanone, PF-4254196, a CCR2 antagonist with an improved cardiovascular profile.

We describe the systematic optimization, focused on the improvement of CV-TI, of a series of CCR2 antagonists. This work resulted in the identification of 10 (((1S,3R)-1-isopropyl-3-((3S,4S)-3-methoxy-tetrahydro-2H-pyran-4-ylamino)cyclopentyl)(4-(5-(trifluoromethyl)pyridazin-3-yl)piperazin-1-yl)methanone) which possessed a low projected human dose 35-45mg BID and a CV-TI=3800-fold.

Crucial contribution of thymic Sirp alpha+ conventional dendritic cells to central tolerance against blood-borne antigens in a CCR2-dependent manner.

Thymic dendritic cells (DCs) as well as thymic epithelial cells are presumed to be major sentinels in central tolerance by inducing the apoptosis of autoreactive T progenitor cells. The thymic DC population is composed of heterogeneous subsets including CD11c(+)B220(+) plasmacytoid DCs, CD11c(+)B220(-)CD8alpha(+) signal regulatory protein alpha (Sirpalpha)(-) and CD11c(+)B220(-)CD8alpha(-)Sirpalpha(+) conventional DCs (cDCs). However, the distinctive role of each DC subset remains undefined. We show herein that Sirpalpha(+) cDCs, a minor subpopulation, was disseminated in the thymic cortical area with some of them uniquely localized inside perivascular regions and nearby small vessels in the thymus. The Sirpalpha(+) but not Sirpalpha(-) cDC subset can selectively capture blood-circulating Ags. Moreover, in CCR2-deficient mice, the thymic Sirpalpha(+) cDC subset, but not other thymic cell components, was moderately decreased especially in the perivascular regions. Concomitantly, these mice exhibited a modest impairment in intrathymic negative selection against blood-borne Ags, with the reduced capacity to uptake blood-borne Ags. Given their intrathymic cortical localization, CD11c(+)B220(-)CD8alpha(-)Sirpalpha(+) cDCs can have a unique role in the development of central tolerance against circulating peripheral Ags, at least partially in a CCR2-dependent manner.

CCR2/CCL2 and CMKLR1/RvE1 chemokines system levels are associated with insulin resistance in rheumatoid arthritis.

Rheumatoid arthritis (RA) has been associated with insulin resistance (IR). Due to an excess in storage of white adipose tissue, IR has an inflammatory process that overlaps with RA. This is performed by the activation/migration of monocytes carried out by the CCR2/CCL2 and CMKLR1/RvE1 chemokines systems. Furthermore, these can potentiate chronic inflammation which is the central axis in the immunopathogenesis of RA. We evaluated the association between the relative expression of CCR2 and CMKLR1 and the serum levels of their ligands CCL2 and RvE1, in the context of adiposity status with IR as a comorbidity in RA. We studied 138 controls and 138 RA-patients classified with and without IR. We evaluated adiposity, RA activity, IR status and immunometabolic profiles by routine methods. Insulin, CCL2 and RvE1 serum levels were determined by ELISA. Relative expression of CCR2, CMKLR1 and RPS28 as constitutive gene by SYBR green RT-qPCR and 2-ΔΔCT method. Increased measurements were observed of body adiposity and metabolic status as follows: RA with IR>control group with IR>RA without IR> control group without IR. CCR2 and CMKLR1 relative expression was increased in RA without IR versus control without IR. CCR2: 2.3- and 1.3-fold increase and CMKLR1: 3.5- and 2.7-fold increase, respectively. Whereas, CCR2 expression correlates with CMKLR1 expression (rho = 0.331) and IR status (rho = 0.497 to 0.548). CMKLR1 expression correlates with inflammation markers (rho = 0.224 to 0.418). CCL2 levels were increased in the RA groups but levels of RvE1 were increased in RA without IR. We conclude that in RA with IR, the chemokine receptors expression pattern showed a parallel increase with their respective ligands. RA and IR in conjunction with the pathological distribution of body fat mass might exacerbate chronic inflammation. These results suggest that high CCL2 levels and compensatory RvE1 levels might not be enough to resolve the inflammation by themselves.

Frequency of CCR5-Δ32, CCR2-64I and SDF1-3'A alleles in HIV-infected and uninfected patients in Istanbul, Turkey.

INTRODUCTION: Co-receptors involved in cell entry of the human immunodeficiency virus (HIV) and mutations in genes encoding their ligands may play a role in the susceptibility to infection and resistance to the progression of the infection. The best studied mutations that can exist in these genes are the CCR5-Δ32, CCR2-64I and SDF1-3'A mutations. The frequency of these mutations vary from continent to continent and even from region to region. However, there is limited information on their distribution throughout the Turkish population. Istanbul is the city with the highest number of documented HIV-infected patients in Turkey, which can be attributed to the population size. The aim of this study was to determine the distribution of three AIDS-related gene variants among HIV-infected and uninfected population in Istanbul, Turkey and to estimate the contribution of these variants to susceptibility or resistance to HIV. METHODOLOGY: A total of 242 healthy individuals and 200 HIV-positive patients were included in the study. CCR5 polymorphisms were genotyped by polymerase chain reaction. CCR2 and SDF1 polymorphisms were genotyped using PCR restriction fragment length polymorphism (PCR-RFLP). RESULTS: The allelic frequencies for CCR5-Δ32, CCR2-64I and SDF1-3'A were 4.07%, 19.8% and 28.7%, respectively. No individual was found to carry the homozygous CCR5-Δ32 mutation in either cohort. No polymorphism was found to be significantly elevated in the HIV-infected cohort compared to the healthy group. CONCLUSIONS: The distribution of CCR5-Δ32, CCR2-64I, and SDF1-3'A variants does not differ between HIV-infected and uninfected patients. CCR2-64I and SDF1-3'A frequencies are relatively high where as the frequency of CCR5-Δ32 is low.

Adiponectin deficiency promotes the production of inflammatory mediators while severely exacerbating hepatic injury in mice with polymicrobial sepsis.

BACKGROUND: Adiponectin (APN), which is an adipose tissue-derived hormone, is known as an anti-inflammatory cytokine. The effects of APN on the production of inflammatory mediators and hepatic injury during polymicrobial sepsis were evaluated using APN-knockout (KO) mice that had undergone a cecal ligation and puncture (CLP) and rosiglitazone, a selective peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, which increases the plasma APN concentration. MATERIALS AND METHODS: Wild type (WT) and APN-KO mice were underwent CLP. The plasma and hepatic levels of inflammatory mediators, including tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1), were measured before, at 24, and 48 h after CLP. A histological analysis of the liver and the plasma alanine aminotransferase (ALT) levels were examined to evaluate hepatic injury. The plasma levels of inflammatory mediators after CLP with pretreatment of rosiglitazone were compared with those without rosiglitazone. RESULTS: APN deficiency resulted in significant increases in the plasma levels of TNF-alpha, IL-6, and MCP-1 at 24 h after CLP. Hepatic MCP-1 and plasma AST levels in APN-KO mice were significantly higher than those in WT mice at 48 h after CLP. A steatosis change and MCP-1 expressions in hepatocytes were induced in APN-KO mice during sepsis. The administration of rosiglitazone significantly lowered the plasma levels of inflammatory mediators, including TNF-alpha, IL-6, and MCP-1, in WT mice but not in APN-KO mice during sepsis. CONCLUSION: These results suggest that an APN deficiency induces an excessive systemic inflammatory status and exacerbates hepatic injury during polymicrobial sepsis.

Tumor necrosis factor alpha is a proximal mediator of synergistic hepatotoxicity from trovafloxacin/lipopolysaccharide coexposure.

The use of trovafloxacin (TVX), a fluoroquinolone antibiotic, was severely restricted because of an association of TVX therapy with idiosyncratic hepatotoxicity in patients. The mechanisms underlying idiosyncratic toxicity are unknown; however, one hypothesis is that an inflammatory stress can render an individual sensitive to the drug. Previously, we reported that treatment of mice with TVX and lipopolysaccharide (LPS) induced tumor necrosis factor (TNF) alpha-dependent liver injury, whereas TVX or LPS treatment alone was nontoxic. The goal of this study was to elucidate the role of TNFalpha in TVX/LPS-induced liver injury. TNF receptor (TNFR) 1 p55(-/-) and TNFR2 (p75(-/-)) mice were protected from hepatotoxicity caused by TVX/LPS coexposure, suggesting that TVX/LPS-induced liver injury requires both TNF receptors. TNFalpha inhibition using etanercept significantly reduced the TVX/LPS-induced increases in the plasma concentrations of several cytokines around the time of onset of liver injury. However, despite the reduction in chemokines, etanercept treatment did not affect the TVX/LPS-induced hepatic accumulation of neutrophils. In addition, etanercept treatment attenuated TVX/LPS induction of plasminogen activator inhibitor-1, and this was associated with a reduction in hepatic fibrin deposition. Mice treated with TVX and a nontoxic dose of TNFalpha also developed liver injury. In summary, TNFalpha acts through p55 and p75 receptors to precipitate an innocuous inflammatory cascade. TVX enhances this cascade, converting it into one that results in hepatocellular injury.

[Change of serum MCP-1 level and CCR2 protein expression in isolated monocytes in patients with acute coronary syndrome].

OBJECTIVE: To investigate the change of serum MCP-1 level and CCR2 expression in isolated monocytes in patients with acute coronary syndrome (ACS) and its possible relationship with ACS pathogenesis. METHODS: Thirty ACS patients and 30 healthy controls were enrolled. Serum MCP-1 levels were determined by ELISA in all subjects. The protein expression of CCR2 in isolated monocytes was assessed by flow cytometry. RESULTS: Serum MCP-1 concentrations in ACS patients were higher than those in healthy controls (P<0.05) and the ratio of CCR2 protein expression in monocytes in ACS patients was higher than that in healthy controls (P<0.01). CONCLUSION: The serum MCP-1 concentrations and protein expression of CCR2 in ACS patients are significantly higher than those in healthy controls, which might be associated with the pathogenesis of ACS.

Gender differences in innate responses and gene expression profiles in memory CD4 T cells are apparent very early during acute simian immunodeficiency virus infection.

Gender differences in Human immunodeficiency virus (HIV) disease progression and comorbidities have been extensively reported. Using the simian immunodeficiency virus (SIV) infected rhesus macaque model, we show that these differences are apparent very early during the course of infection. Though there were no major changes in the proportions of CD4 T cells or its subsets, central memory CD4 T cells from female macaques were found to differentially regulate a significantly larger number of genes at day 4 post-infection (PI) as compared to males. Pathway analysis revealed divergence of both canonical and biological pathways that persisted at day 10 PI. Changes in gene expression profiles were accompanied by a significant increase in plasma levels of pro-inflammatory mediators such as MCP-1/CCL2, I-TAC/CXCL11, and MIF. Though plasma levels of IFNα did not differ between male and female macaques, the expression levels of IFNα subtype-14, 16, IFNß, and IFNω were significantly upregulated in the lymph nodes of female macaques at day 10 PI as compared to male macaques. Our results suggest that the pathogenic sequelae seen during chronic infection may be shaped by gender differences in immune responses induced very early during the course of HIV infection.