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In this article the author examines the causes and effects of CC chemokine receptor 5 (CCR5). The author states that the null state of CCR5 is associated with early symptom development and more pronounced clinical manifestations after infection with West Nile virus (WNV), a mosquito-borne neutropic flavivirus. He adds that the null state is due to homozygosity for the European-specific 32 base pair (bp) coding deletion mutation.

The basis for the extensive variability seen in the reconstitution of CD4+ T cell counts in HIV-infected individuals receiving highly active antiretroviral therapy (HAART) is not fully known. Here, we show that variations in CCL3L1 gene dose and CCR5 genotype, but not major histocompatibility complex HLA alleles, influence immune reconstitution, especially when HAART is initiated at <350 CD4+ T cells/mm3. The CCL3L1-CCR5 genotypes favoring CD4+ T cell recovery are similar to those that blunted CD4+ T cell depletion during the time before HAART became available (pre-HAART era), suggesting that a common CCL3L1-CCR5 genetic pathway regulates the balance between pathogenic and reparative processes from early in the disease course. Hence, CCL3L1-CCR5 variations influence HIV pathogenesis even in the presence of HAART and, therefore, may prospectively identify subjects in whom earlier initiation of therapy is more likely to mitigate immunologic failure despite viral suppression by HAART. Furthermore, as reconstitution of CD4+ cells during HAART is more sensitive to CCL3L1 dose than to CCR5 genotypes, CCL3L1 analogs might be efficacious in supporting immunological reconstitution. [ABSTRACT FROM AUTHOR]

The prevailing paradigm is that in human rheumatoid arthritis (RA), the accumulation of monocytes and T cells in the joint, mediated in part by such CC chemokine receptors (CCRs) as CCR2 and CCR5, respectively, plays a central role in disease pathogenesis. To further validate this paradigm, we conducted proof-of-principle studies and tested the hypothesis that gene inactivation of Ccr2 or Ccr5 will ameliorate experimental RA. Contrary to our expectations, we found that in two well-established murine models of experimental RA, CCR2 expression in the hematopoietic cell compartment served as a negative regulator of autoantibody production as well as arthritic disease onset, severity, and resolution. In contrast, the RA phenotype in Ccr5-null mice was similar to that of WT mice. Remarkably, the collagen-induced arthritis phenotype of Ccr2-/- mice mimicked closely that of severe human RA, including production of rheumatoid factor, enhanced T cell production, and monocyte/macrophage accumulation in the joints. Our findings demonstrate an essential protective role of CCR2 expression in RA, indicate the existence of alternative receptors responsible for monocyte/macrophage accumulation to inflamed joints, and emphasize the need to clarify carefully the complex effects of the chemokine system in RA before they can be considered as therapeutic targets. [ABSTRACT FROM AUTHOR]

The prevailing paradigm is that in human rheumatoid arthritis (RA), the accumulation of monocytes and T cells in the joint, mediated in part by such CC chemokine receptors (CCRs) as CCR2 and CCR5, respectively, plays a central role in disease pathogenesis. To further validate this paradigm, we conducted proof-of-principle studies and tested the hypothesis that gene inactivation of Ccr2 or Ccr5 will ameliorate experimental RA. Contrary to our expectations, we found that in two well-established murine models of experimental RA, CCR2 expression in the hematopoietic cell compartment served as a negative regulator of autoantibody production as well as arthritic disease onset, severity, and resolution. In contrast, the RA phenotype in Ccr5-null mice was similar to that of WT mice. Remarkably, the collagen-induced arthritis phenotype of Ccr2-/- mice mimicked closely that of severe human RA, including production of rheumatoid factor, enhanced T cell production, and monocyte/macrophage accumulation in the joints. Our findings demonstrate an essential protective role of CCR2 expression in RA, indicate the existence of alternative receptors responsible for monocyte/macrophage accumulation to inflamed joints, and emphasize the need to clarify carefully the complex effects of the chemokine system in RA before they can be considered as therapeutic targets. [ABSTRACT FROM AUTHOR]

Introduction: Mortality rates in schizophrenia patients due to cardiovascular events are reported to be more than the general population. Dyslipidaemia, obesity, diabetes, and hypertension are some of the common illnesses these patients are vulnerable to develop. The drugs which are used to treat schizophrenia and other related disorders i.e. antipsychotics causes increase in weight, dyslipidaemia and insulin resistance in some patients. Some agent's i.e. Second Generation Antipsychotics (SGA) cause more of the above mentioned symptoms and than others agent's i.e. First Generation Antipsychotics (FGA). The novelty of the study includes the emergence of Metabolic syndrome (MetS) in drug naïve or drug free patients who were prescribed trifluoperazine and olanzapine and comparative study of them. Aim: To assess the emergence of MetS in drug naïve patients of schizophrenia after the administration of trifluoperazine-FGA and olanzapine-SGA. Materials and Methods: A cohort study was conducted from May 2019 to March 2021, in the Department of Psychiatry, Shyam Shah Medical College, and Rewa, Madhya Pradesh, India. Study was started after the clearance from institutional ethical committee. The study included 41 drug naïve indoor and outdoor patients, diagnosed as schizophrenia according to International Classification of Diseases 10 Diagnostic Criteria for Research (ICD 10 DCR). The patients were divided into two groups, one group was prescribed FGA trifluoperazine and other was prescribed SGA olanzapine. Twenty patients were prescribed olanzapine and 21 patient's trifluoperazine. Metabolic parameters were taken before onset of drug treatment therapy, after two and four months respectively. The patients were given medications for four months. The changes in metabolic parameters i.e., waist circumference, blood pressure, Fasting Blood Sugar (FBS), triglycerides, and Low HDL (High Density Lipoprotein) were compared using unpaired student's t-test and repeated measure Analysis of Variance (ANOVA) with p-value <0.05 considered as significant. Results: It was found that out of total 41 patient, 4 patients (19.4%) and 12 patients (60%) patients prescribed trifluoperazine and olanzapine respectively developed Mets after four months of antipsychotic medication. Also, there was a significant change in various parameters of MetS in both groups as seen in repeated measure ANOVA. Conclusion: SGA cause significantly more changes in the metabolic parameters and compared to the FGA, increasing the likelihood of developing MetS and associated disorders like cerebrovascular accidents and diabetes mellitus type-II. [ABSTRACT FROM AUTHOR]

Importance: Large-scale estimates of bronchopulmonary dysplasia (BPD) are warranted for adequate prevention and treatment. However, systematic approaches to ascertain rates of BPD are lacking. Objective: To conduct a systematic review and meta-analysis to assess the prevalence of BPD in very low birth weight (≤ 1,500 g) or very low gestational age (< 32 weeks) neonates. Data sources: A search of MEDLINE from January 1990 until September 2019 using search terms related to BPD and prevalence was performed. Study selection: Randomized controlled trials and observational studies evaluating rates of BPD in very low birth weight or very low gestational age infants were eligible. Included studies defined BPD as positive pressure ventilation or oxygen requirement at 28 days (BPD28) or at 36 weeks postmenstrual age (BPD36). Data extraction and synthesis: Two reviewers independently conducted all stages of the review. Random-effects meta-analysis was used to calculate the pooled prevalence. Subgroup analyses included gestational age group, birth weight group, setting, study period, continent, and gross domestic product. Sensitivity analyses were performed to reduce study heterogeneity. Main outcomes and measures: Prevalence of BPD defined as BPD28, BPD36, and by subgroups. Results: A total of 105 articles or databases and 780,936 patients were included in this review. The pooled prevalence was 35% (95% CI, 28-42%) for BPD28 (n = 26 datasets, 132,247 neonates), and 21% (95% CI, 19-24%) for BPD36 (n = 70 studies, 672,769 neonates). In subgroup meta-analyses, birth weight category, gestational age category, and continent were strong drivers of the pooled prevalence of BPD. Conclusions and relevance: This study provides a global estimation of BPD prevalence in very low birth weight/low gestation neonates. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented, which pleads for the release of six medical workers jailed in Libya for intentionally infecting 400 children, who were treated as out patients in the Al-Fateh Hospital, Benghazi, Libya.

Presents a commentary on the article in this issue which address the question of why some people do not contract HIV-1 despite repeated exposure to the virus. How growing evidence suggests that differences in genetic makeup may be the reason for such variability in susceptibility; Proposal that human leucocyte antigens (HLA) have a role; Reasons this may seem counter-intuitive; Finding of the study that the similarity or disparity of HLA-class-1 alleles between sexual partners may have an important role in the risk of acquiring HIV infection; Implications for use in clinical medicine; How the information may not be good news for researchers working on vaccines against HIV.

Bronchopulmonary dysplasia (BPD) is the most common lung disease of extreme prematurity, yet mechanisms that associate with or identify neonates with increased susceptibility for BPD are largely unknown. Combining artificial intelligence with gene expression data is a novel approach that may assist in better understanding mechanisms underpinning chronic lung disease and in stratifying patients at greater risk for BPD. The objective of this study is to develop an early peripheral blood transcriptomic signature that can predict preterm neonates at risk for developing BPD. Secondary analysis of whole blood microarray data from 97 very low birth weight neonates on day of life 5 was performed. BPD was defined as positive pressure ventilation or oxygen requirement at 28 days of age. Participants were randomly assigned to a training (70%) and testing cohort (30%). Four gene-centric machine learning models were built, and their discriminatory abilities were compared with gestational age or birth weight. This study adheres to the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) statement. Neonates with BPD (n = 62 subjects) exhibited a lower median gestational age (26.0 wk vs. 30.0 wk, P < 0.01) and birth weight (800 g vs. 1,280 g, P < 0.01) compared with non-BPD neonates. From an initial pool (33,252 genes/ patient), 4,523 genes exhibited a false discovery rate (FDR) <1%. The area under the receiver operating characteristic curve (AUC) for predicting BPD utilizing gestational age or birth weight was 87.8% and 87.2%, respectively. The machine learning models, using a combination of five genes, revealed AUCs ranging between 85.8% and 96.1%. Pathways integral to T cell development and differentiation were associated with BPD. A derived five-gene whole blood signature can accurately predict BPD in the first week of life. [ABSTRACT FROM AUTHOR]

Studies have investigated CCR5 haplotypes (HHA, HHB, HHC, HHD, HHE, HHF*1, HHF*2, HHG*1, HHG*2), defined by seven 5′UTR single nucleotide polymorphisms (SNPs), CCR2-V64I and CCR5Δ32, in HIV-1 disease. CCR5 cis-regulatory regions were sequenced, CCR2-V64I and CCR5Δ32 genotyped, and compared in HIV-1-infected black South Africans: 71 HIV-1 controllers (23 elite controllers, 37 viraemic controllers (VCs), 11 high viral load long-term non-progressors) and 74 progressors. The HHE haplotype and 3′UTR +2919 T > G SNP heterozygosity were underrepresented in total controllers and VCs vs. progressors (p =.004; p =.007 and p =.002, p bonferroni = 0.032; p =.004, respectively). Possession of the +2919 T > G SNP (dominant mode) was associated with HIV-1 progression (controllers vs. progressors: p =.001, p bonferroni = 0.016). The +2919 T > G SNP is in linkage disequilibrium (LD; r2 = 0.73) with two 5′UTR SNPs (−2459G > A and -2135 T > C; r2 = 1: 5′UTR-2SNP-hap). The 5′UTR-2SNP-hap was lower in total controllers and VCs vs. progressors (p =.003, p bonferroni = 0.048; p =.01, respectively). Results suggest -2459G > A, −2135 T > C, and + 2919 T > G as key CCR5 variants in HIV-1 control. [ABSTRACT FROM AUTHOR]

Objective: The role of CC chemokine receptor 5 (CCR5) and its ligand CCL5 on the pathogenesis of HIV infection has been well studied but not for HCV infection. Here, we investigated whether CCL5 haplotypes influence HIV and HCV seropositivity among 373 Caucasian people who inject drugs (PWID) from Estonia. Methods: Study included 373 PWID; 56% were HIV seropositive, 44% HCV seropositive and 47% co-infected. Four CCL5 haplotypes (A-D) were derived from three CCL5 polymorphisms (rs2107538/rs2280788/rs2280789) typed by Taqman allelic discrimination assays. The data of CCR5 haplotypes were used from our previous study. The association between CCL5 haplotypes with HIV and/or HCV seropositivity was determined using logistic regression analysis. Results: Possessing CCL5 haplotype D (defined by rs2107538A/rs2280788G/rs2280789C) decreased the odds of HCV seropositivity compared to those not possessing it (OR = 0.19; 95% CI 0.09–0.40), which remained significant after adjustment to co-variates (OR = 0.08; 95% CI 0.02–0.29). An association of this haplotype with HIV seropositivity was not found. In step-wise logistic regression with backward elimination CCL5 haplotype D and CCR5 HHG*1 had reduced odds for HCV seropositivity (OR = 0.28 95% CI 0.09–0.92; OR = 0.23 95% CI 0.08–0.68, respectively) compared to those who did not possess these haplotypes, respectively. Conclusions: Our results suggest that among PWID CCL5 haplotype D and CCR5 HHG*1 independently protects against HCV. Our findings highlight the importance of CCL5 genetic variability and CCL5-CCR5 axis on the susceptibility to HCV. [ABSTRACT FROM AUTHOR]

The influence of the diversity of CCR5 on HIV susceptibility and disease progression has been clearly demonstrated but how the variability of this gene influences the HIV tropism is poorly understood. We investigated whether CCR5 haplotypes are associated with HIV tropism in a Caucasian population.We evaluated 161 HIV-positive subjects in a cross-sectional study. CCR5 haplotypes were derived after genotyping 9 CCR2-CCR5 polymorphisms. The HIV subtype was determined by phylogenetic analysis using the maximum likelihood method and viral tropism by the genotypic tropism assay (geno2pheno). Associations between CCR5 haplotypes and viral tropism were determined using logistic regression analyses. Samples from 500 blood donors were used to evaluate the representativeness of HIV-positives in terms of CCR5 haplotype distribution.The distribution of CCR5 haplotypes was similar in HIV-positive subjects and blood donors. The majority of viruses (93.8%) belonged to HIV-1 CRF06_cpx; 7.5% were X4, and the remaining were R5 tropic. X4 tropic viruses were over represented among people with CCR5 human haplotype E (HHE) compared with those without this haplotype (13.0% vs 1.4%; P = 0.006). People possessing CCR5 HHE had 11 times increased odds (odds ratio = 11.00; 95% confidence interval: 1.38 to 87.38) of having X4 tropic viruses than those with non-HHE. After adjusting for antiretroviral (ARV) therapy, neither the presence of HHE nor the use of ARV was associated with X4 tropic viruses.Our results suggest that CCR5 HHE and ARV treatment might be associated with the presence of HIV-1 X4 tropic viruses. [ABSTRACT FROM AUTHOR]

Background: Up to 90% HIV-1 positive intravenous drug users (IDUs) are co-infected with HCV. Although best recognized for its function as a major co-receptor for cell entry of HIV, CC chemokine receptor 5 (CCR5) has also been implicated in the pathogenesis of HCV infection. Here, we investigated whether CCR5 haplotypes influence HIV-1 and HCV seropositivity among 373 Caucasian IDUs from Estonia. Methods: Of these IDUs, 56% and 44% were HIV and HCV seropositive, respectively, and 47% were coinfected. 500 blood donors seronegative for HIV and HCV were also evaluated. CCR5 haplotypes (HHA to HHG*2) were derived after genotyping nine CCR2–CCR5 polymorphisms. The association between CCR5 haplotypes with HIV and/or HCV seropositivity was determined using logistic regression analysis. Co-variates included in the models were length of intravenous drug use, HBV serostatus and copy number of CCL3L1, the gene encoding the most potent HIV-suppressive chemokine and ligand for CCR5. Results: Compared to IDUs seronegative for both HCV and HIV (HCV−/HIV-), IDUs who were HCV+/HIV- and HCV+/HIV+were 92% and 82%, respectively, less likely to possess the CCR5-HHG*1 haplotype, after controlling for co-variates (Padjusted = 1.89×10−4 and 0.003, respectively). This association was mostly due to subjects bearing the CCR5 HHE and HHG*1 haplotype pairs. Approximately 25% and<10% of HCV−/HIV- IDUs and HCV−/HIV- blood donors, respectively, possessed the HHE/HHG*1 genotype. Conclusions: Our findings suggest that HHG*1-bearing CCR5 genotypes influence HCV seropositivity in a group of Caucasian IDUs. [ABSTRACT FROM AUTHOR]

Cytokines play an important role in ischemic injury and repair. However, little is known about their prognostic value in cardiovascular disease. The aim of this study was to investigate the prognostic importance of chemokines CCL3/MIP-1a, CCL5/RANTES and CCL18/PARC for the risk of future cardiovascular events in patients with acute coronary syndromes (ACS). Baseline levels of CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC were determined in ACS patients from the Bad Nauheim ACS II registry (n = 609). During the following 200 days, patients were monitored for the occurrence of fatal and non-fatal cardiovascular events. Patients with CCL3/MIP1α, CCL5/RANTES and CCL18/PARC concentrations in the highest tertile were associated with an increased risk of a fatal event during follow-up (HR: 2.19, 95%CI: 1.04-4.61 for CCL3/MIP1α, HR: 3.45, 95%CI: 1.54-7.72 for CCL5/RANTES and HR: 3.14, 95%CI: 1.33-7.46 for CCL18/PARC). This risk was highest for patients with all three biomarkers concentrations in the upper tertile (HR: 2.52, 95%CI: 1.11-5.65). Together with known risk predictors of cardiovascular events, CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC combined improved the c-statistics from 0.74 to 0.81 (p = 0.007). In conclusion, CCL3/MIP-1α, CCL5/RANTES and CCL18/PARC are independently associated with the risk of short-term mortality in ACS patients. Combining all three biomarkers further increased their prognostic value. [ABSTRACT FROM AUTHOR]

Background: Quality of life (QoL) in patients with chronic disease is impaired and cannot be solely explained by disease severity. We explored whether genetic variability and activity contributes to QoL in patients with Marfan syndrome (MFS), a genetic connective tissue disorder. Methodology/Principal Findings: In 121 MFS patients, patient characteristics (i.e. demographics and MFS-related symptoms) were assessed. Patients completed the SF-36 to measure QoL. In addition, transcriptome wide gene expression and 484 Single Nucleotide Polymorphysms (SNPs) in cytokine genes were available. QoL was first analyzed and associated with patient characteristics. Patients' physical QoL was impaired and weakly related with age and scoliosis, whereas mental quality of life (MCS) was normal. To explain a largely lacking correlation between disease severity and QoL, we related genome wide gene expression to QoL. Patients with lower MCS scores had high expression levels of CXCL9 and CXCL11 cytokine-related genes (p = 0.001; p = 0.002); similarly, patients with low vitality scores had high expression levels of CXCL9, CXCL11 and IFNA6 cytokine-related genes (p = 0.02; p = 0.02; p = 0.04), independent of patient characteristics. Subsequently, we associated cytokine related SNPs to mental QoL (MCS and vitality). SNP-cluster in the IL4R gene showed a weak association with MCS and vitality (strongest association p = 0.0017). Although overall mental QoL was normal, .10% of patients had low scores for MCS and vitality. Post-hoc analysis of systemic inflammatory mediators showed that patients with lowest MCS and vitality scores had high levels of CCL11 cytokine (p = 0.03; p = 0.04). Conclusions/Significance: Variation in the cytokine genetic pathway and its activation is related to mental QoL. These findings might allow us to identify and, ultimately, treat patients susceptible to poor QoL. [ABSTRACT FROM AUTHOR]

Background: IFN-γ is presently the only soluble immunological marker used to help diagnose latent Mycobacterium tuberculosis (M.tb) infection. However, IFN-γ is not available to distinguish latent from active TB infection. Moreover, extrapulmonary tuberculosis, such as tuberculous pleurisy, cannot be properly diagnosed by IFN-γ release assay. As a result, other disease- or infection-related immunological biomarkers that would be more effective need to be screened and identified. Methodology: A panel of 41 soluble immunological molecules (17 cytokines and 24 chemokines) was tested using Luminex liquid array-based multiplexed immunoassays. Samples, including plasma and pleural effusions, from healthy donors (HD, n = 12) or patients with latent tuberculosis infection (LTBI, n = 20), pulmonary tuberculosis (TB, n = 12), tuberculous pleurisy (TP, n = 15) or lung cancer (LC, n = 15) were collected and screened for soluble markers. Peripheral blood mononuclear cells (PBMCs) and pleural fluid mononuclear cells (PFMCs) were also isolated to investigate antigen-specific immune factors. Principal Findings: For the 41 examined factors, our results indicated that three patterns were closely associated with infection and disease. (1) Significantly elevated plasma levels of IL-2, IP-10, CXCL11 and CXCL12 were present in both patients with tuberculosis and in a sub-group participant with latent tuberculosis infection who showed a higher level of IFN-c producing cells by ELISPOT assay compared with other latently infected individuals. (2) IL-6 and IL-9 were only significantly increased in plasma from active TB patients, and the two factors were consistently highly secreted after M.tb antigen stimulation. (3) When patients developed tuberculous pleurisy, CCL1, CCL21 and IL-6 were specifically increased in the pleural effusions. In particular, these three factors were consistently highly secreted by pleural fluid mononuclear cells following M.tb-specific antigen stimulation. In conclusion, our data imply that the specific secretion of soluble immunological factors, in addition to IFN-c, may be used to evaluate M.tb infection and tuberculosis disease. [ABSTRACT FROM AUTHOR]

Natural variation in DNA sequence contributes to individual differences in quantitative traits. While multiple studies have shown genetic control over gene expression variation, few additional cellular traits have been investigated. Here, we investigated the natural variation of NADPH oxidase-dependent hydrogen peroxide (H2O2 release), which is the joint effect of reactive oxygen species (ROS) production, superoxide metabolism and degradation, and is related to a number of human disorders. We assessed the normal variation of H2O2 release in lymphoblastoid cell lines (LCL) in a family-based 3-generation cohort (CEPH-HapMap), and in 3 population-based cohorts (KORA, GenCord, HapMap). Substantial individual variation was observed, 45% of which were associated with heritability in the CEPH-HapMap cohort. We identified 2 genome-wide significant loci of Hsa12 and Hsa15 in genome-wide linkage analysis. Next, we performed genome-wide association study (GWAS) for the combined KORA-GenCord cohorts (n = 279) using enhanced marker resolution by imputation (>1.4 million SNPs). We found 5 significant associations (p<5.00x10- 8) and 54 suggestive associations (p<1.00x10-5), one of which confirmed the linked region on Hsa15. To replicate our findings, we performed GWAS using 58 HapMap individuals and ~2.1 million SNPs. We identified 40 genome-wide significant and 302 suggestive SNPs, and confirmed genome signals on Hsa1, Hsa12, and Hsa15. Genetic loci within 900 kb from the known candidate gene p67phox on Hsa1 were identified in GWAS in both cohorts. We did not find replication of SNPs across all cohorts, but replication within the same genomic region. Finally, a highly significant decrease in H2O2 release was observed in Down Syndrome (DS) individuals (p<2.88x10-12). Taken together, our results show strong evidence of genetic control of H2O2 in LCL of healthy and DS cohorts and suggest that cellular phenotypes, which themselves are also complex, may be used as proxies for dissection of complex disorders. [ABSTRACT FROM AUTHOR]

Background: Chemokines and their receptors play a role in the innate immune response as well as in the disruption of the balance between pro-inflammatory Th17 cells and regulatory T cells (Treg), underlying the pathogenesis of coronary vasculitis in Kawasaki disease (KD). Results: Here we show that genetic inactivation of chemokine receptor (CCR)-2 is protective against the induction of aortic and coronary vasculitis following injection of Candida albicans water-soluble cell wall extracts (CAWS). Mechanistically, both T and B cells were required for the induction of vasculitis, a role that was directly modulated by CCR2. CAWS administration promoted mobilization of CCR2-dependent inflammatory monocytes (iMo) from the bone marrow (BM) to the periphery as well as production of IL-6. IL-6 was likely to contribute to the depletion of Treg and expansion of Th17 cells in CAWS-injected Ccr2+/+ mice, processes that were ameliorated following the genetic inactivation of CCR2. Conclusion: Collectively, our findings provide novel insights into the role of CCR2 in the pathogenesis of vasculitis as seen in KD and highlight novel therapeutic targets, specifically for individuals resistant to first-line treatments. [ABSTRACT FROM AUTHOR]

The relationship between CD4+ T-cell counts determined soon after seroconversion with HIV-1 (baseline CD4), nadir CD4, and CD4 levels attained during highly active antiretroviral therapy (HAART) is unknown.Longitudinal, including baseline (at or soon after HIV diagnosis), intermediate (nadir), and distal (post-HAART) CD4+ T-cell counts were assessed in 1085 seroconverting subjects who achieved viral load suppression from a large well-characterized cohort. The association of baseline with post-HAART CD4+ T-cell count was determined after adjustment for other relevant covariates.A higher baseline CD4+ T-cell count predicted a greater post-HAART CD4+ T-cell count, independent of the nadir and other explanatory variables. Together, baseline and nadir strongly predicted the post-HAART CD4+ count such that a high baseline and lower nadir were associated with a maximal immune recovery after HAART. Likelihood of recovery of the baseline count after HAART was significantly higher when the nadir/baseline count ratio was consistently ≥0.6.Among viral load suppressing seroconverters, the absolute CD4+ T-cell count attained post-HAART is highly dependent on both baseline and nadir CD4+ T-cell counts. These associations further support the early diagnosis and initiation of HAART among HIV-infected persons. [ABSTRACT FROM AUTHOR]

We investigated the association of polymorphisms in CCR5, the major human immunodeficiency virus (HIV)–1 coreceptor, and copy number of its potent ligand CCL3L1 with tuberculosis in 298 individuals from Colombia. The CCR5-HHD haplotype, a known genetic determinant of increased susceptibility to HIV-AIDS, and a high copy number of CCL3L1, a known genetic determinant of enhanced CCL3/CCL3L1 chemokine expression, each associated with presence of tuberculosis. Furthermore, CCR5-HHD was associated with higher CCR5 gene and surface expression. These results substantiate the strong link between the pro-inflammatory effects of CCR5 and its ligands with active tuberculosis and suggest that chemokine-chemokine receptor genetic determinants may influence tuberculosis in addition to HIV/AIDS. [ABSTRACT FROM PUBLISHER]

The Duffy-null trait and ethnic neutropenia are highly prevalent in Africa. The authors found that the trait of Duffy-null–associated low neutrophil counts associated with increased HIV-1 susceptibility. The possible contribution of this trait to the high prevalence of HIV-1 in Africa requires further investigationBackground. The Duffy-null trait and ethnic netropenia are both highly prevalent in Africa. The influence of pre-seroconversion levels of peripheral blood cell counts (PBCs) on the risk of acquiring human immunodeficiency virus (HIV)–1 infection among Africans is unknown.Methods. The triangular relationship among pre-seroconversion PBC counts, host genotypes, and risk of HIV acquisition was determined in a prospective cohort of black South African high-risk female sex workers. Twenty-seven women had seroconversion during follow-up, and 115 remained HIV negative for 2 years, despite engaging in high-risk activity.Results. Pre-seroconversion neutrophil counts in women who subsequently had seroconversion were significantly lower, whereas platelet counts were higher, compared with those who remained HIV negative. Comprising 27% of the cohort, subjects with pre-seroconversion neutrophil counts of <2500 cells/mm3 had a ∼3-fold greater risk of acquiring HIV infection. In a genome-wide association analyses, an African-specific polymorphism (rs2814778) in the promoter of Duffy Antigen Receptor for Chemokines (DARC −46T > C) was significantly associated with neutrophil counts (P = 7.9 × 10−11). DARC −46C/C results in loss of DARC expression on erthyrocytes (Duffy-null) and resistance to Plasmodium vivax malaria, and in our cohort, only subjects with this genotype had pre-seroconversion neutrophil counts of <2500 cells/mm3. The risk of acquiring HIV infection was ∼3-fold greater in those with the trait of Duffy-null–associated low neutrophil counts, compared with all other study participants.Conclusions. Pre-seroconversion neutrophil and platelet counts influence risk of HIV infection. The trait of Duffy-null–associated low neutrophil counts influences HIV susceptibility. Because of the high prevalence of this trait among persons of African ancestry, it may contribute to the dynamics of the HIV epidemic in Africa. [ABSTRACT FROM AUTHOR]

Background: The impact of viral load (VL) decay and cumulative VL on CD4 recovery and AIDS after highly-active antiretroviral therapy (HAART) is unknown. Methods and Findings: Three virologic kinetic parameters (first year and overall exponential VL decay constants, and first year VL slope) and cumulative VL during HAART were estimated for 2,278 patients who initiated HAART in the U.S. Military HIV Natural History Study. CD4 and VL trajectories were computed using linear and nonlinear Generalized Estimating Equations models. Multivariate Poisson and linear regression models were used to determine associations of VL parameters with CD4 recovery, adjusted for factors known to correlate with immune recovery. Cumulative VL higher than the sample median was independently associated with an increased risk of AIDS (relative risk 2.38, 95% confidence interval 1.56-3.62, p<0.001). Among patients with VL suppression, first year VL decay and slope were independent predictors of early CD4 recovery (p = 0.001) and overall gain (p<0.05). Despite VL suppression, those with slow decay during the first year of HAART as well as during the entire therapy period (overall), in general, gained less CD4 cells compared to the other subjects (133 vs. 195.4 cells/μL; p = 0.001) even after adjusting for potential confounders. Conclusions: In a cohort with free access to healthcare, independent of established predictors of AIDS and CD4 recovery during HAART, cumulative VL and virologic decay patterns were associated with AIDS and distinct aspects of CD4 reconstitution. [ABSTRACT FROM AUTHOR]

We used cutaneous delayed-type hypersensitivity responses, a powerful in vivo measure of cell-mediated immunity, to evaluate the relationships among cell-mediated immunity, AIDS, and polymorphisms in CCR5, the HIV-1 coreceptor. There was high concordance between CCR5 polymorphisms and haplotype pairs that influenced delayed-type hypersensitivity responses in healthy persons and HIV disease progression. In the cohorts examined, CCR5 genotypes containing -2459G/G (HHA/HHA, HHA/HHC, HHC/HHC) or -2459A/A (HHE/HHE) associated with salutary or detrimental delayed-type hypersensitivity and AIDS phenotypes, respectively. Accordingly, the CCR5-Δ32 allele, when paired with non-Δ32-bearing haplotypes that correlate with low (HHA, HHC) versus high (HHE) CCR5 transcriptional activity, associates with disease retardation or acceleration, respectively. Thus, the associations of CCR5-Δ32 heterozygosity partly reflect the effect of the non-Δ32 haplotype in a background of CCR5 haploinsufficiency. The correlations of increased delayed-type hypersensitivity with -2459G/G-containing CCR5 genotypes, reduced CCR5 expression, decreased viral replication, and disease retardation suggest that CCR5 may influence HIV infection and AIDS, at least in part, through effects on cell-mediated immunity. [ABSTRACT FROM AUTHOR]

Aneurysms of the vascular wall represent a final common pathway for a number of inflammatory processes, including atherosclerosis and idiopathic vasculitis syndromes. Kawasaki disease (KD) is an acute, self-limited vasculitis in children and the leading cause of acquired coronary artery aneurysms. We sought to identify shared molecular mechanisms of aneurysm formation by genotyping eight polymorphisms in matrix metalloproteinase (MMP)-1, 3, 7, 12 and 13 in the gene cluster on Chr.11q22, whose gene products have been implicated in aneurysm formation or are known to have elastase activity. We genotyped 482 US-UK KD patients (aneurysm+: n=111, aneurysm−: n=371) and tested our findings in an independent cohort of 200 Japanese KD patients (aneurysm+: n=58, aneurysm−: n=142). Analysis of the five MMP genes identified modest trends in allele and genotype frequencies for MMP-3 rs3025058 (−/T) and haplotypes containing MMP-3 rs3025058 (−/T) and MMP-12 rs2276109 (A/G) (nominal P=2 to 4 × 10−5) that conferred increased risk of aneurysm formation in US-UK subjects. This finding was validated in Japanese subjects and suggests the importance of this locus in aneurysm formation in children with KD. The region encompassing these risk haplotypes is a prime candidate for resequencing to look for rare genetic variation that may influence aneurysm formation. [ABSTRACT FROM AUTHOR]

Background: The etiology of Kawasaki Disease (KD) is enigmatic, although an infectious cause is suspected. Polymorphisms in CC chemokine receptor 5 (CCR5) and/or its potent ligand CCL3L1 influence KD susceptibility in US, European and Korean populations. However, the influence of these variations on KD susceptibility, coronary artery lesions (CAL) and response to intravenous immunoglobulin (IVIG) in Japanese children, who have the highest incidence of KD, is unknown. Methodology/Principal Findings: We used unconditional logistic regression analyses to determine the associations of the copy number of the CCL3L1 gene-containing duplication and CCR2-CCR5 haplotypes in 133 Japanese KD cases [33 with CAL and 25 with resistance to IVIG] and 312 Japanese controls without a history of KD. We observed that the deviation from the population average of four CCL3L1 copies (i.e.< , or > four copies) was associated with an increased risk of KD and IVIG resistance (adjusted odds ratio (OR) = 2.25, p = 0.004 and OR = 6.26, p = 0.089, respectively). Heterozygosity for the CCR5 HHF*2 haplotype was associated with a reduced risk of both IVIG resistance (OR = 0.21, p = 0.026) and CAL development (OR = 0.44, p = 0.071). Conclusions/Significance: The CCL3L1-CCR5 axis may play an important role in KD pathogenesis. In addition to clinical and laboratory parameters, genetic markers may also predict risk of CAL and resistance to IVIG. [ABSTRACT FROM AUTHOR]

Background. Despite suppression of the human immunodeficiency virus type1 (HIV-1)load by highly active antiretroviral therapy (HAART), recovery of CD4+ Tcell counts can be impaired. We investigated whether this impairment may be associated with hyporesponsiveness of T cells to γ-chain (γc) cytokines known to influence T cell homeostasis. Methods. The responsiveness of T cells to interleukin (IL)-2, IL-7, and IL-15 was determined by assessing cytokine-induced phosphorylation of the signal transducer and activator of transcription 5 (STAT5) in peripheral T cells obtained from 118 HIV-positive subjects and 13 HIV-negative subjects. Results. The responsiveness of T cells to interleukin (IL)-7 but not to IL-2 or IL-15 was lower among HIV-positive subjects than among HIV-negative subjects. Among subjects with viral load suppression, the degree of IL-7 responsiveness (1) correlated with naive CD4+ T cell counts and was a better immune correlate of the prevailing CD4+ T cell count than were levels of human leukocyte antigen-DR1 or programmed death-1, which are predictors of T cell homeostasis during HIV infection; and (2) was greater in subjects with complete (i.e., attainment of ⩾500 CD4+ T cells/mm³ ⩾5 years after initiation of HAART) versus incomplete immunologic responses. The correlation between plasma levels of IL-7 and CD4+ T cell counts during HAART was maximal in subjects with increased IL-7 responsiveness. Conclusions. Responsiveness of T cells to IL-7 is associated with higher CD4+ T cell counts during HAART and thus may be a determinant of the extent of immune reconstitution. [ABSTRACT FROM AUTHOR]

In this article the author discusses the co-evolution of primate and viral genomes and its link to chemokine ligands 3 (CCL3). The author refers to the study of Degenhardt and colleagues which examined the association of copy number variations (CNV) and disease susceptibility in non-human primates. The author believes that the findings of Degenhardt and colleagues have practical implications in the development of effective HIV vaccine through the stratified rhesus on chemokine CNV.

Background: Polymorphisms in CCR5, the major coreceptor for HIV, and CCL3L1, a potent CCR5 ligand and HIV-suppressive chemokine, are determinants of HIV-AIDS susceptibility. Here, we mathematically modeled the potential impact of these genetic factors on the epidemic spread of HIV, as well as on its prevention. Methods and Results: Ro, the basic reproductive number, is a fundamental concept in explaining the emergence and persistence of epidemics. By modeling sexual transmission among HIV+/HIV2 partner pairs, we find that Ro estimates, and concordantly, the temporal and spatial patterns of HIV outgrowth are highly dependent on the infecting partners' CCL3L1- CCR5 genotype. Ro was least and highest when the infected partner possessed protective and detrimental CCL3L1-CCR5 genotypes, respectively. The modeling data indicate that in populations such as Pygmies with a high CCL3L1 gene dose and protective CCR5 genotypes, the spread of HIV might be minimal. Additionally, Pc, the critical vaccination proportion, an estimate of the fraction of the population that must be vaccinated successfully to eradicate an epidemic was <1 only when the infected partner had a protective CCL3L1-CCR5 genotype. Since in practice Pc cannot be >1, to prevent epidemic spread, population groups defined by specific CCL3L1-CCR5 genotypes might require repeated vaccination, or as our models suggest, a vaccine with an efficacy of .70%. Further, failure to account for CCL3L1-CCR5-based genetic risk might confound estimates of vaccine efficacy. For example, in a modeled trial of 500 subjects, misallocation of CCL3L1-CCR5 genotype of only 25 (5%) subjects between placebo and vaccine arms results in a relative error of ∼12% from the true vaccine efficacy. Conclusions: CCL3L1-CCR5 genotypes may impact on the dynamics of the HIV epidemic and, consequently, the observed heterogeneous global distribution of HIV infection. As Ro is lowest when the infecting partner has beneficial CCL3L1-CCR5 genotypes, we infer that therapeutic vaccines directed towards reducing the infectivity of the host may play a role in halting epidemic spread. Further, CCL3L1-CCR5 genotype may provide critical guidance for optimizing the design and evaluation of HIV-1 vaccine trials and prevention programs. [ABSTRACT FROM AUTHOR]

A recent genome-wide association study (GWAS) suggested that polymorphisms in or around the genes HCP5, HLA-C and ZNRD1 confer restriction against HIV-1 viral replication or disease progression. Here, we also find that these alleles are associated with different aspects of HIV disease, albeit mainly in European Americans. Additionally, we offer that because the GWAS cohort was a subset of HIV-positive individuals, selected based in part on having a low viral load, the observed associations for viral load are magnified compared with those we detect in a large well-characterized prospective natural history cohort of HIV-1-infected persons. We also find that because of linkage disequilibrium (LD) patterns, the dominant viral load- and disease-influencing associations for the ZNRD1 or HLA-C and HCP5 alleles are apparent mainly when these alleles are present in HLA-A10- or HLA-B*57-containing haplotypes, respectively. ZNRD1 alleles lacking HLA-A10 did not confer disease protection whereas ZNRD1-A10 haplotypes did. When examined in isolation, the HCP5-G allele associates with a slow disease course and lower viral loads. However, in multivariate models, after partitioning out the protective effects of B*57, the HCP5-G allele associates with disease-acceleration and enhanced viral replication; these associations for HCP5-G are otherwise obscured because of the very strong LD between this allele and a subset of protective B*57 alleles. Furthermore, HCP5 and HLA-C alleles stratify B*57-containing genotypes into those that associate with either striking disease retardation or progressive disease, providing one explanation for the long-standing conundrum of why some HLA-B*57-carrying individuals are long-term non-progressors, whereas others exhibit progressive disease. Collectively, these data generally underscore the strong dependence of genotype-phenotype relationships upon cohort design, phenotype selection, LD patterns and populations studied. They specifically demonstrate that the influence of ZNRD1 alleles on disease progression rates are attributable to HLA-A10, help clarify the relationship between the HCP5, HLA-C and HLA-B*57 alleles, and reaffirm a critical role of HLA-B*57 alleles in HIV disease. Furthermore, as the protective B*57-containing genotypes convey striking salutary effects independent of their strong impact on viral control, it is conceivable that T cell-based therapeutic vaccine strategies aimed at reducing viral loads may be inadequate for limiting AIDS progression, raising the potential need for complementary strategies that target viral load-independent determinants of pathogenesis. [ABSTRACT FROM AUTHOR]

Background: Whether vexing clinical decision-making dilemmas can be partly addressed by recent advances in genomics is unclear. For example, when to initiate highly active antiretroviral therapy (HAART) during HIV-1 infection remains a clinical dilemma. This decision relies heavily on assessing AIDS risk based on the CD4+ T cell count and plasma viral load. However, the trajectories of these two laboratory markers are influenced, in part, by polymorphisms in CCR5, the major HIV coreceptor, and the gene copy number of CCL3L1, a potent CCR5 ligand and HIV-suppressive chemokine. Therefore, we determined whether accounting for both genetic and laboratory markers provided an improved means of assessing AIDS risk. Methods and Findings: In a prospective, single-site, ethnically-mixed cohort of 1,132 HIV-positive subjects, we determined the AIDS risk conveyed by the laboratory and genetic markers separately and in combination. Subjects were assigned to a low, moderate or high genetic risk group (GRG) based on variations in CCL3L1 and CCR5. The predictive value of the CCL3L1- CCR5 GRGs, as estimated by likelihood ratios, was equivalent to that of the laboratory markers. GRG status also predicted AIDS development when the laboratory markers conveyed a contrary risk. Additionally, in two separate and large groups of HIV+ subjects from a natural history cohort, the results from additive risk-scoring systems and classification and regression tree (CART) analysis revealed that the laboratory and CCL3L1-CCR5 genetic markers together provided more prognostic information than either marker alone. Furthermore, GRGs independently predicted the time interval from seroconversion to CD4+ cell count thresholds used to guide HAART initiation. Conclusions: The combination of the laboratory and genetic markers captures a broader spectrum of AIDS risk than either marker alone. By tracking a unique aspect of AIDS risk distinct from that captured by the laboratory parameters, CCL3L1- CCR5 genotypes may have utility in HIV clinical management. These findings illustrate how genomic information might be applied to achieve practical benefits of personalized medicine. [ABSTRACT FROM AUTHOR]

Background. The in vivo impact of mannose-binding lectin (MBL), a molecule involved in innate immunity, on the pathogenesis of human immunodeficiency virus (HIV)-1 infection and AIDS is unknown. Methods. A total of 1102 HIV-positive and 2213 HIV-negative adult subjects were screened for polymorphisms in the coding and promoter regions of MBL2, the gene that encodes MBL. Results. Variations in MBL2 did not influence the risk of acquiring HIV-1. Heterozygosity for coding mutations (O allele) and homozygosity for the -221 promoter polymorphism (X allele) in MBL2 were associated with a delay in and an accelerated rate of disease progression, respectively. MBL2 variations influenced the rate of progression to AIDS-defining illnesses. In a multivariate model, the effects of MBL2 variations were independent of several parameters known to influence disease progression, including steady-state viral load, baseline CD4+ T cell counts, and delayed-type hypersensitivity skin test responses, an in vivo marker of cell-mediated immunity. The effects of MBL2 variations were most evident in those who possessed protective genotypes of CCR5 and a high copy number of CCL3L1, the most potent HIV-suppressive CCR5 ligand. Conclusions. MBL2 genotypes are independent determinants of HIV disease progression and heterozygosity for MBL2 coding mutations confer disease-retarding effects. MBL-dependent immune responses may play a role in the pathogenesis of HIV infection. [ABSTRACT FROM AUTHOR]

Originally recognized for their role in lipoprotein metabolism and cardiovascular disease, apolipoprotein (apo) E isoforms (apoE2, apoE3, and apoE4) have also been implicated to play a key role in several biological processes not directly related to their lipid transport function. For example, apoE4 contributes significantly to neurodegeneration in Alzheimer's disease. However, the role of apoE in infectious diseases is less well defined. Here, by examining a large cohort of HIV+ European and African American subjects, we found that the APOE ϵ4/ϵ4 genotype is associated with an accelerated disease course and especially progression to death compared with the APOE ϵ3/ϵ3 genotype. However, an association between the ϵ4/ϵ4 genotype and HIV-associated dementia (HAD), a neurological condition with clinicopathological features similar to Alzheimer's disease, was not detected. Consistent with the genotype-phenotype relationships observed, compared with recombinant apoE3, apoE4 enhanced HIV fusion/cell entry of both R5 and X4 HIV strains in vitro. These findings establish apoE as a determinant of HIV-AIDS pathogenesis and raise the possibility that current efforts to convert apoE4 to an "apoE3-like" molecule to treat Alzheimer's disease might also have clinical applicability in HIV disease. [ABSTRACT FROM AUTHOR]

Abstract: Chemotactic factors known as chemokines play an important role in the pathogenesis of multiple sclerosis (MS). Transgenic expression of TNFα in the central nervous system (CNS) leads to the development of a demyelinating phenotype (TNFα-induced demyelination; TID) that is highly reminiscent of MS. Little is known about the role of chemokines in TID but insights derived from studying this model might extend our current understanding of MS pathogenesis and complement data derived from the classic autoimmune encephalomyelitis (EAE) model system. Here we show that in TID, chemokines and their receptors were significantly increased during the acute phases of disease. Notably, the CCL2 (MCP-1)–CCR2 axis and the closely related ligand–receptor pair CCR1–CCL3 (MIP-1α) were among the most up-regulated during disease. On the other hand, receptors like CCR3 and CCR4 were not elevated. This significant increase in the levels of chemokines/receptors correlated with robust immune infiltration of the CNS by inflammatory cells, i.e., macrophages, and immune cells particularly T and B cells. Immunostaining and confocal microscopy, along with in vitro studies revealed that astrocytes were a major source of locally produced chemokines and expressed functional chemokine receptors such as CCR2. Using an in vitro system we demonstrate that expression of CCR2 was functional in astrocytes and that signaling via this receptor lead to activation of NF-kB and Akt and was associated with increased astrocyte survival. Collectively, our data suggests that transgenic murine models of MS are useful to dissect mechanisms of disease and that in these models, up-regulation of chemokines and their receptors may be key determinants in TID. [Copyright &y& Elsevier]

Abstract: Several CCR5 ligands, including small molecules and monoclonal antibodies (MAbs), are being developed as therapies for infection with strains of human immunodeficiency virus type 1 (HIV-1) that use CCR5 for entry (R5 viruses). The efficacy of such therapies could be influenced by inter-individual differences in host factors, such as CCR5 expression levels. To study this, we used peripheral blood mononuclear cells (PBMCs) from humans and rhesus macaques. The half-maximal inhibitory concentrations (IC50) of the small-molecule CCR5 ligands CMPD167, UK427,857 and SCH-D, and of the PRO 140 MAb, differ by >2 logs in a donor-dependent manner. We studied this variation by using flow cytometry to measure CCR5 expression on PBMCs from six of the human donors: the IC50 values of both SCH-D and PRO 140 correlated with CCR5 expression (R 2 =0.64 and 0.99, respectively). We also determined the efficacy of the CCR5 ligands against HIV-1 infection of HeLa-derived cell lines that express CD4 at the same level but vary 2-fold in CCR5 expression (JC.48 and JC.53 cells). The moderately greater CCR5 expression on the JC.53 than the JC.48 cells was associated with proportionately higher median IC50 values for all four CCR5 ligands but not for a soluble CD4-based inhibitor or a non-nucleoside reverse transcriptase inhibitor. We conclude that differences in CCR5 expression on human PBMCs, which can be affected by CCL3L1 gene dose, may influence the antiviral potency of CCR5 ligands in vitro, but other host factors are also likely to be involved. These host factors may affect the clinical activity of CCR5 inhibitors, including their use as topical microbicides to prevent HIV-1 transmission. [Copyright &y& Elsevier]

Abstract: Recent studies have invoked inflammation as a major contributor to the pathogenesis of Parkinson’s disease (PD). We determined the role of members of the chemokine system, key inflammatory mediators, in PD pathogenesis. In the MPTP model of murine PD, several chemokines, including CC chemokine ligand 2 (CCL2, Monocyte Chemoattractant Protein-1) and CCL3 (Macrophage Inflammatory Protein-1α), were upregulated in the striatum and the ventral midbrain. Astrocytes were the predominant source of CCL2 and CCL3 in the striatum and the substantia nigra, and dopaminergic neurons in the substantia nigra constitutively expressed these two chemokines. MPTP treatment resulted in decreased CCL2 expression and increased CCL3 expression in the surviving dopaminergic neurons. Because we found that CCL2 induced production of TNF-α in microglial cells, a cytokine known to play a detrimental role in PD, we anticipated that deletion of the genes encoding CCL2 and CCR2, its major receptor, would confer a protective phenotype. However, MPTP-induced striatal dopamine depletion was comparable in double knockout and wild-type mice. Our results demonstrate that chemokines such as CCL2 are induced following MPTP treatment, but that at least within the context of this PD model, the absence of CCL2 and CCR2 does not protect against striatal dopamine loss. [Copyright &y& Elsevier]

The host factors that influence autoimmune arthritides such as rheumatoid arthritis have not been fully elucidated. We previously found that genetic inactivation of CC chemokine receptor 2 (CCR2) in the arthritis-prone DBA/1j mouse strain significantly increases the susceptibility of this strain to autoimmune arthritis induced by immunization with collagen type II (CII) and complete Freund’s adjuvant (CFA). Here, we show that following intradermal infection with Mycobacterium avium, a similar arthritis phenotype was detected in Ccr2-null mice in the DBA/1j, but not in the BALB/c background. The failure to develop arthritis in Ccr2-null BALB/c mice occurred in the face of high bacterial burdens and low interferon gamma (IFNγ) production. By contrast, Ccr2-null DBA/1j mice had low bacterial burdens, produced normal amounts of IFNγ, and had high titers of autoantibodies against CII. Thus, the Ccr2-null state in an arthritic-prone genetic background leads to increased arthritis susceptibility following infectious ( M. avium) and noninfectious (CII/CFA) challenges. Because CCR2 serves as a negative regulator of murine arthritis, caution might need to be exercised while testing CCR2 blockers in human arthritis or other diseases. These findings also indicate that Ccr2-null DBA/1j mice might serve as a valuable model system to uncover the immunological determinants of arthritis and to test novel antiarthritic agents. [ABSTRACT FROM AUTHOR]

CCR2 has been widely considered as a potential therapeutic target for autoimmune disease, particularly rheumatoid arthritis, and various CCR2 blocking agents have been developed, some of which have entered clinical trials. In this review, we examine the relevant information regarding the role of CCR2, and to a lesser extent of the closely related chemokine receptor CCR5, in the immunopathogenesis of collagen-induced arthritis, an animal model of rheumatoid arthritis. Experimental evidence showing that CIA is accelerated and exacerbated when CCR2 is genetically inactivated (knockout mice) or blocked with specific antibodies warrant additional investigations before the relevance of the findings in rodent models can be applied to human patients with RA. [ABSTRACT FROM AUTHOR]

Kawasaki disease (KD) is an enigmatic, self-limited vasculitis of childhood that is complicated by development of coronary-artery aneurysms. The high incidence of KD in Asian versus European populations prompted a search for genetic polymorphisms that are differentially distributed among these populations and that influence KD susceptibility. Here, we demonstrate a striking, inverse relationship between the worldwide distribution of CCR5- Delta 32 allele and the incidence of KD. In 164 KD patient-parent trios, 4 CCR5 haplotypes including the CCR5- Delta 32 allele were differentially transmitted from heterozygous parents to affected children. However, the magnitude of the reduced risk of KD associated with the CCR5- Delta 32 allele and certain CCR5 haplotypes was significantly greater in individuals who also possessed a high copy number of the gene encoding CCL3L1, the most potent CCR5 ligand. These findings, derived from the largest genetic study of any systemic vasculitis, suggest a central role of CCR5-CCL3L1 gene-gene interactions in KD susceptibility and the importance of gene modifiers in infectious diseases. [ABSTRACT FROM AUTHOR]

Analyzes the influence of genetic variation in monocyte chemoattractant protein-1 (MCP-1), a potent chemoattractant and activator of mononuclear phagocytes on the pathogenesis of HIV-associated dementia. Ability of MCP-1 to up-regulate HIV-1 replication; Increased risk of dementia by MCP-1 genotype; Transcriptional activity of MCP-1-2578G allele.

Examines the role of balancing selection in shaping the variation patterns of CC chemokine receptor 5 (CCR5). Association of varied HIV-1 susceptibility with polymorphisms in CCR5; Genealogy of CCR5 haplotypes; Consequences of adaptive changes in older pathogens.

Presents information on a study which investigated the role of CC chemokine receptor 5 genetic variation in the context of children exposed to perinatally to HIV-1 infection. Methodology; Results of the study; Discussion.

Examines the relevance of the variation in the expression of the CC chemokine gene receptor on the epidemiology of HIV infections. Impact on the distribution of variation in the genes; Details of the heterogenous nature of the epidemiology of HIV infections.

The article outlines the result of the research regarding the efficacy trial of an adenovirus serotype 5 (Ad5) vector-based HIV-2 vaccine in the U.S. It was undertaken in November 2008 and result reveals that not only was the vaccine ineffective at lowering plasma viremia postinfection but it may increase the risk of acquiring HIV-1 infection. Eventhough researchers cannot draw conclusions on the small number of infections that occurred in the trial group, it has been suggested that vaccine-induced generalized immune activation which can promote HIV-1 replication might have increased the infection risk.

Abstract: Members of the chemokine system, play a central role in inflammatory processes that underlie the pathogenesis of atherosclerosis and possibly, aortic valve sclerosis. Here we show that genetic inactivation of CC chemokine receptor 5 (CCR5) in the atherosclerosis-prone Apoe −/− mice (Apoe −/− Ccr5 −/−) fed a normal chow or a high-fat diet (HFD) are protected against advanced atherosclerosis as well as age-associated aortic valve thickening (AAAVT)—a murine correlate of aortic valve sclerosis. Notably, human sclerotic valves contained CCR5+ cells. We confirm that Apoe −/− Ccr5 −/− mice does not influence early-atherosclerotic stage. Adoptive transfer studies showed that the atheroprotective effect of CCR5 inactivation resided in the bone marrow compartment, but was not dependent on T-cells. The CCR5-null state was associated with phenotypes postulated to be atheroprotective such as reduced macrophage accumulation in the plaque, and lower circulating levels of IL-6 and MCP-5. The lack of CCR5 expression in Apoe −/− mice was also associated with higher numbers of endothelial progenitor cells (EPCs)—another postulated athero-protective factor. Compared with controls, carriers of a polymorphism in the Ccr5 gene that leads to the lack of CCR5 in the cell surface had an increased mean percentage of EPCs, but this difference did not reach statistical significance. Collectively, these findings underscore a critical role of CCR5 in age-associated cardiovascular diseases, and highlight that the effects of the chemokine system can be temporally constrained to distinct stages of these disease processes. [Copyright &y& Elsevier]