Search

Background: The homeostatic chemokines CCL19 and CCL21 are involved in carotid plaque vulnerability and post-ischemic neuroinflammatory responses. This study aimed to examine the prognostic values of CCL19 and CCL21 in ischemic stroke., Methods: Plasma CCL19 and CCL21 were measured in 4483 ischemic stroke patients from two independent cohorts of CATIS (China Antihypertensive Trial in Acute Ischemic Stroke) and IIPAIS (Infectious Factors, Inflammatory Markers, and Prognosis of Acute Ischemic Stroke), and participants were followed up at 3 months after stroke. The primary outcome was the composite outcome of death or major disability. The associations of CCL19 and CCL21 levels with the primary outcome were examined., Results: In CATIS, multivariable-adjusted odds ratios of the primary outcome in the highest quartiles of CCL19 and CCL21 compared with the lowest quartiles were 2.06 and 2.62, respectively. In IIPAIS, odds ratios of the primary outcome in the highest quartiles of CCL19 and CCL21 were 2.81 and 2.78 compared with the lowest quartiles, respectively. In the pooled analysis of the two cohorts, odds ratios of the primary outcome associated with the highest quartiles of CCL19 and CCL21 were 2.24 and 2.66, respectively. Similar findings were observed in the analysis with major disability, death, and the composite outcome of death or cardiovascular events as the secondary study outcomes. Adding CCL19 and CCL21 to conventional risk factors significantly improved risk reclassification and discrimination for adverse outcomes., Conclusions: Both CCL19 and CCL21 levels were independently associated with adverse outcomes within 3 months after ischemic stroke and should be further investigated for risk stratification and potential therapeutic targets of ischemic stroke., (© 2023 European Academy of Neurology.)

Objective: Response to immunosuppression is highly variable in systemic sclerosis (SSc)-related interstitial lung disease (ILD). This study was undertaken to determine whether a composite serum interferon (IFN)-inducible protein score exhibits predictive significance for the response to immunosuppression in SSc-ILD., Methods: Serum samples collected in the Scleroderma Lung Study II, a randomized controlled trial of mycophenolate mofetil (MMF) versus cyclophosphamide (CYC), were examined. Results were validated in an independent observational cohort receiving active treatment. A composite score of 6 IFN-inducible proteins IFNγ-inducible 10-kd protein, monokine induced by IFNγ, monocyte chemotactic protein 2, β 2 -microglobulin, tumor necrosis factor receptor type II, and macrophage inflammatory protein 3β) was calculated, and its predictive significance for longitudinal forced vital capacity percent predicted measurements was evaluated., Results: Higher baseline IFN-inducible protein score predicted better response over 3 to 12 months in the MMF arm (point estimate = 0.41, P = 0.001) and CYC arm (point estimate = 0.91, P = 0.009). In contrast, higher baseline C-reactive protein (CRP) levels were predictive of a worse ILD course in both treatment arms. The predictive significance of the IFN-inducible protein score and CRP levels remained after adjustment for baseline demographic and clinical predictors. During the second year of treatment, in which patients in the CYC arm were switched to placebo, a higher IFN-inducible protein score at 12 months showed a trend toward predicting a worse ILD course (point estimate = -0.61, P = 0.068), while it remained predictive of better response to active immunosuppression in the MMF arm (point estimate = 0.28, P = 0.029). The predictive significance of baseline IFN-inducible protein score was replicated in the independent cohort (r s = 0.43, P = 0.028)., Conclusion: A higher IFN-inducible protein score in SSc-ILD is predictive of better response to immunosuppression and could potentially be used to identify patients who may derive the most benefit from MMF or CYC., (© 2020, American College of Rheumatology.)

The disease course of children with coronavirus disease 2019 (COVID-19) seems milder as compared with adults, however, actual reason of the pathogenesis still remains unclear. There is a growing interest on possible relationship between pathogenicity or disease severity and biomarkers including cytokines or chemokines. We wondered whether these biomarkers could be used for the prediction of the prognosis of COVID-19 and improving our understanding on the variations between pediatric and adult cases with COVID-19. The acute phase serum levels of 25 cytokines and chemokines in the serum samples from 60 COVID-19 pediatric (n = 30) and adult cases (n = 30) including 20 severe or critically ill, 25 moderate and 15 mild patients and 30 healthy pediatric (n = 15) and adult (n = 15) volunteers were measured using commercially available fluorescent bead immunoassay and analyzed in combination with clinical data. Interferon gamma-induced protein 10 (IP-10) and macrophage inflammatory protein (MIP)-3β levels were significantly higher in patient cohort including pediatric and adult cases with COVID-19 when compared with all healthy volunteers (p ≤ .001 in each) and whereas IP-10 levels were significantly higher in both pediatric and adult cases with severe disease course, MIP-3β were significantly lower in healthy controls. Additionally, IP-10 is an independent predictor for disease severity, particularly in children and interleukin-6 seems a relatively good predictor for disease severity in adults. IP-10 and MIP-3β seem good research candidates to understand severity of COVID-19 in both pediatric and adult population and to investigate possible pathophysiological mechanism of COVID-19., (© 2020 Wiley Periodicals LLC.)

Background: The chemokines CCL19 and CCL21 are up-regulated in atherosclerotic disease and heart failure, and increased circulating levels are found in unstable versus stable coronary artery disease., Objectives: The purpose of this study was to evaluate the prognostic value of CCL19 and CCL21 in acute coronary syndrome (ACS)., Methods: CCL19 and CCL21 levels were analyzed in serum obtained from ACS patients (n = 1,146) on the first morning after hospital admission. Adjustments were made for GRACE (Global Registry of Acute Coronary Events) score, left ventricular ejection fraction, pro-B-type natriuretic peptide, troponin I, and C-reactive protein levels., Results: The major findings were: 1) those having fourth quartile levels of CCL21 on admission of ACS had a significantly higher long-term (median 98 months) risk of major adverse cardiovascular events (MACE) and myocardial infarction in fully adjusted multivariable models; 2) high CCL21 levels at admission were also independently associated with MACE and cardiovascular mortality during short-time (3 months) follow-up; and 3) high CCL19 levels at admission were associated with the development of heart failure., Conclusions: CCL21 levels are independently associated with outcome after ACS and should be further investigated as a promising biomarker in these patients., (Copyright © 2019 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Introduction:: Clinical studies have unraveled a negative association between diabetes and abdominal aortic aneurysm (AAA), but the mechanisms involved are still poorly understood. The aim of this study was to determine whether diabetic patients with AAA had a distinct plasma inflammatory profile compared to nondiabetic patients., Methods:: Plasma samples were obtained from 10 diabetic patients with AAA and 10 nondiabetic patients with AAA. The relative protein expression of 92 inflammatory-related human protein biomarkers was assessed by proximity extension assay technology using Proseek Multiplex Inflammation I kit (Olink)., Results:: Clinical characteristics were similar in diabetic patients with AAA compared to nondiabetic patients with AAA, the median ages being 67 and 73 years, respectively ( P = .61). The AAA diameters were, respectively, 50 and 49 mm ( P = .72). Among the 92 markers screened, 67 (72.8%) were detected in all samples. Diabetic patients had significantly lower protein expression of C-C motif chemokine 19 (CCL19) and C-C motif chemokine 23 (CCL23; 542.3 vs 980.3, P = .01 and 1236 vs 1406, P = .04, respectively). They tended to have higher expression of tumor necrosis factor ligand superfamily member 14 (TNFSF14) compared to controls (14.6 vs 10.8, P = .05)., Conclusion:: Diabetic patients with AAA differentially expressed CCL19, CCL23 and TNFSF14 in plasma compared to nondiabetic patients with AAA. Further studies are required to determine whether the markers identified could play a role in the negative association between diabetes and AAA pathogenesis.

Objective Clinically useful serum biomarkers for the diagnosis and monitoring of eosinophilic gastrointestinal diseases are not available. This study was conducted to examine the possible value of eosinophil-related proteins as serum biomarkers. Methods The serum concentrations of 49 cytokines, chemokines, and other proteins were measured in 29 patients with eosinophilic gastrointestinal diseases and 80 controls. Results The levels of interleukin (IL)-5, IL-33, eotaxin-3, and thymic stromal lymphopoietin (TSLP), previously reported as possible biomarkers of eosinophilic esophagitis, were not significantly elevated in the serum. In contrast, the B cell-attracting chemokine (BCA)-1/chemokine (C-X-C motif) ligand (CXCL) 13 and hemofiltrate C-C chemokine (HCC)-1/CC chemokine ligand (CCL) 14α levels were significantly elevated, while the granulocyte chemotactic protein (GCP)-2/CXCL6 levels were suppressed in patients with eosinophilic esophagitis as well as in those with eosinophilic gastroenteritis. The cutaneus T cell-attracting chemokine (CTACK)/CCL27, stromal cell-derived factor (SDF)-1/CXCL12, macrophage inflammatory protein (MIP)-3β/CCL19, and squamous cell carcinoma antigen (SCCA) 2 levels were elevated only in patients with eosinophilic esophagitis. However, there were large overlaps of data obtained from the patient and control groups, indicating that these serum biomarkers are not adequately sensitive for clinical use with presently available assay systems. Conclusion Of the 49 investigated serum proteins, none were shown to be adequately sensitive for use as biomarkers for the diagnosis or monitoring of eosinophilic gastrointestinal diseases.

Objective: To detect the levels of serum C-C chemokine ligand 19 (CCL19) in patients with systemic lupus erythematosus (SLE) and to evaluate the correlation between CCL19 expression and clinical features and laboratory parameters, trying to reveal the possible role of CCL19 in the pathogenesis of systemic lupus erythematosus., Methods: The levels of serum CCL19 were measured by enzyme linked immunosorbent assay (ELISA) in 90 patients with SLE and 30 healthy controls. These SLE patients included 75 patients who received treatment with glucocorticoids and disease-modifying anti-rheumatic drug (DMARD) and 15 patients without therapy. The frequencies of peripheral blood B cells and the B cell subsets were assessed in the patients with SLE by flow cytometry. The correlation between the clinical data, laboratory parameters, B cell subset frequencies and serum CCL19 levels were analyzed. Indepen-dent samples t test, paired t test, Pearson and Spearman correlation were used for statistical analyses., Results: The levels of CCL19 were markedly higher in the SLE patients without therapy and the patients with therapy than in the health controls[(596.25±409.19) ng/L and (422.90±395.84) ng/L vs. (157.79±125.23) ng/L, all P<0.001]. Serum CCL19 levels in the SLE patients without therapy were higher than the SLE patients who accepted glucocorticoids and DMARD treatment (P<0.05). The levels of serum CCL19 were positively correlated with anti-double stranded deoxyribonucleic acid (dsDNA), anti-nucleosome antibody (AnuA), IgA, IgG and IgM (r=0.38, P=0.007; r=0.332, P=0.029; r=0.519, P=0.007; r=0.461, P=0.018, respectively). Serum CCL19 levels in the SLE patients with photosensitivity, arthritis and secondary Sjögren's syndrome were higher than the SLE patients without photosensitivity, arthritis and secondary Sjögren's syndrome, respectively [(562.25±399.12) ng/L, (565.6±435.24) ng/L and (694.9±531.02) ng/L vs. (394.7±281.42) ng/L, (385.90±325.33) ng/L and (424.8±305.46) ng/L, all P<0.05]. The levels of serum CCL19 were positively correlated with the percentage of CD27-B cells and CD27-IgD-double-negative memory B cells (r=0.519, P=0.007; r=0.461, P=0.018, respectively). However, the levels of serum CCL19 were negatively correlated with the percentage of CD27 + memory B cells and CD27 + IgD - switched memory B cells (r=-0.433, P=0.027; r=-0.616, P=0.001, respectively)., Conclusion: The increased serum CCL19 levels in SLE patients were associated with the production of autoantibodies, and CCL19 might be involved in the pathogenesis of SLE by disturbing the homeostasis of B cell subsets.

Osteoclasts are responsible for the bone erosion associated with rheumatoid arthritis (RA). The upregulation of the chemokines CCL19 and CCL21 and their receptor CCR7 has been linked to RA pathogenesis. The purpose of this study was to evaluate the effects of CCL19 and CCL21 on osteoclasts and to reveal their underlying mechanisms. The expression of CCL19, CCL21 and CCR7 was higher in RA patients than in osteoarthritis patients. In differentiating osteoclasts, tumor necrosis factor-α, interleukin-1β and lipopolysaccharide stimulated CCR7 expression. CCL19 and CCL21 promoted osteoclast migration and resorption activity. These effects were dependent on the presence of CCR7 and abolished by the inhibition of the Rho signaling pathway. CCL19 and CCL21 promoted bone resorption by osteoclasts in an in vivo mice calvarial model. These findings demonstrate for the first time that CCL19, CCL21 and CCR7 play important roles in bone destruction by increasing osteoclast migration and resorption activity. This study also suggests that the interaction of CCL19 and CCL21 with CCR7 is an effective strategic focus in developing therapeutics for alleviating inflammatory bone destruction.

Approximately 10% to 20% of patients optimally treated for early Lyme disease develop persistent symptoms of unknown pathophysiology termed posttreatment Lyme disease syndrome (PTLDS). The objective of this study was to investigate associations between PTLDS and immune mediator levels during acute illness and at several time points following treatment. Seventy-six participants with physician-documented erythema migrans and 26 healthy controls with no history of Lyme disease were enrolled. Sixty-four cytokines, chemokines, and inflammatory markers were measured at each visit for a total of 6 visits over 1 year. An operationalized definition of PTLDS incorporating symptoms and functional impact was applied at 6 months and 1 year following treatment completion, and clinical outcome groups were defined as the return-to-health, symptoms-only, and PTLDS groups. Significance analysis of microarrays identified 7 of the 64 immune mediators to be differentially regulated by group. Generalized logit regressions controlling for potential confounders identified posttreatment levels of the T-cell chemokine CCL19 to be independently associated with clinical outcome group. Receiver operating characteristic analysis identified a CCL19 cutoff of >111.67 pg/ml at 1 month following treatment completion to be 82% sensitive and 83% specific for later PTLDS. We speculate that persistently elevated CCL19 levels among participants with PTLDS may reflect ongoing, immune-driven reactions at sites distal to secondary lymphoid tissue. Our findings suggest the relevance of CCL19 both during acute infection and as an immunologic risk factor for PTLDS during the posttreatment phase. Identification of a potential biomarker predictor for PTLDS provides the opportunity to better understand its pathophysiology and to develop early interventions in the context of appropriate and specific clinical information., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

Objective: To investigate the serum level of C-C chemokine ligand 19 (CCL19) and its clinical significance in rheumatoid arthritis., Methods: The serum CCL19 levels in both rheumatoid arthritis (RA) patients and health controls were detected by ELISA. The proportion of peripheral blood B cells and memory B cell subsets were also detected in some patients. Then the clinical and laboratory data of the patients were collected. The CCL19 levels in patients with different clinical features were analyzed. And the correlation between the clinical data, laboratory parameters, B cell subsets proportion and serum CCL19 levels were also analyzed. Independent samples t test, paired t test, Pearson and Spearman correlation were used for statistical analysis., Results: The levels of CCL19 was higher in the RA patients than the health controls (P<0.05). The serum CCL19 levels were decreased in the RA patients who accepted disease-modifying anti-rheumatic drugs (DMARDs) treatment for 6 months (P<0.001). Serum CCL19 levels were correlated with the titers of both rheumatoid factor (RF) and anti-cyclic citrullinated peptide (CCP) antibody (r=0.42, P=0.002; r=0.33, P=0.013), but not with erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and disease activity score in 28 joints (DAS28) (P>0.05). The levels of CCL19 were higher in the serum positive (RF and anti-CCP antibody) patients, but there were no differences between low and high disease activity RA, as well as early and non-early RA. There was no correlation between the serum CCL19 levels and the proportion of B cells as well as memory B subsets. All the proportion of peripheral blood CD27+ memory B cell subsets in RA was lower than the healthy controls, including CD27+IgD+, CD27+IgD- and CD27+ B cells., Conclusion: The increased serum CCL19 levels in RA patients are associated with the activity of B cells, so CCL19 might predict whether the RA type is a B cell mediated RA, and specify the treatment directions for the rheumatologist.

Ethnicity is a key factor impacting on disease severity in SLE, but molecular mechanisms of these associations are unknown. Type I IFN and MIF have each been associated with SLE pathogenesis. We investigated whether increased SLE severity in Asian patients is associated with either MIF or Type I IFN. SLE patients (n = 151) had prospective recording of disease variables. Serum MIF, and a validated composite score of three Type I IFN-inducible chemokines (IFNCK:CCL2, CXCL10, CCL19) were measured. Associations of MIF and IFNCK score with disease activity were assessed, with persistent active disease (PAD) used as a marker of high disease activity over a median 2.6 years follow up. In univariable analysis, MIF, IFNCK score and Asian ethnicity were significantly associated with PAD. Asian ethnicity was associated with higher MIF but not IFNCK score. In multivariable logistic regression analysis, MIF (OR3.62 (95% CI 1.14,11.5), p = 0.03) and Asian ethnicity (OR3.00 (95% CI 1.39,6.46), p < 0.01) but not IFNCK were significantly associated with PAD. These results potentially support an effect of MIF, but not Type I IFN, in heightened SLE disease severity in Asian SLE. The associations of MIF and Asian ethnicity with PAD are at least partly independent.

Background: It is well-documented that both chemokine (C-C motif) ligand 19 (CCL19) and 21 (CCL21) mediate cell migration and angiogenesis in many diseases. However, these ligands' precise pathological role in ankylosing spondylitis (AS) has not been elucidated. The objective of this study was to examine the expression of CCL19 and CCL21 (CCL19/CCL21) in AS hip ligament tissue (LT) and determine their pathological functions., Methods: The expression levels of CCL19, CCL21 and their receptor CCR7 in AS (n = 31) and osteoarthritis (OA, n = 21) LT were analyzed via real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC). The expression of CCL19, CCL21 and CCR7 in AS ligament fibroblasts was also detected. The proliferation of ligament fibroblasts was measured via a cell counting kit-8 (CCK8) assay after exogenous CCL19/CCL21 treatment. Additionally, the role of CCL19/CCL21 in osteogenesis was evaluated via RT-PCR and enzyme-linked immunosorbent assay (ELISA) in individual AS fibroblast cultures. Furthermore, the expression of the bone markers alkaline phosphatase (ALP), osteocalcin (OCN), collagenase I (COL1), integrin-binding sialoprotein (IBSP) and the key regulators runt-related transcription factor-2 (Runx-2) and osterix were investigated. Moreover, the CCL19/CCL21 levels in serum and LT were measured via ELISA., Results: The mRNA levels of CCL19/CCL21 in AS hip LT were significantly higher than that in OA LT, and IHC analysis revealed a similar result. Exogenous CCL19/CCL21 treatment did not affect the proliferation of ligament fibroblasts but significantly up-regulated the expression of bone markers, including ALP and OCN, and the key regulators Runx-2 and osterix. In addition, the serum levels of CCL19/CCL21 were apparently elevated in AS patients compared to healthy controls (HC), and the expression of the two chemokines correlated significantly in AS patients., Conclusions: CCL19 and CCL21, two chemokines displaying significantly associated expression in serum, indicating a synergistic effect on AS pathogenesis, may function as promoters of ligament ossification in AS patients.

Background: Based on their essential role in concerting immunological and inflammatory responses we hypothesized that the homeostatic chemokines CCL19 and CCL21 may play a pathogenic role in rickettsiae infection., Methods: Serum levels of CCL19 and CCL21 in patients with R. africae and R. conorii infection were analyzed by enzyme immunoassays. Lungs from R. conorii infected mice were examined for CCL19, CCL21 and CCR7 expression by immunohistochemistry., Results: We found that patients with R. africae infection (n = 15) and in particular those with R. conorii infection (n = 16) had elevated serum levels of CCL19 on admission, with a decline during follow-up. While a similar pattern was seen for CCL21 in R. africae infection, patients with R. conorii infection showed persistently increased CCL21 levels during follow-up. In experimental R. conorii infection, we found strong immunostaining of CCL19 and CCL21 in the lungs, particularly in individuals that had received lethal doses. Immunofluorescence showed co-localization of CCR7 to endothelial cells, macrophages and fibroblasts within the lung tissue of R. conorii infected mice., Conclusions: Our findings suggest that the CCL19/CCL21/CCR7 axis is up-regulated during R. africae and in particular during R. conorii infection, which may potentially contribute to the pathogenesis of these disorders.

Background/aims: Genome-wide association (GWA) studies have reported susceptible regions in the human genome for many common diseases and traits; however, these loci only explain a minority of trait heritability. To boost the power of a GWA study, substantial research endeavors have been focused on integrating other available genomic information in the analysis. Advances in high through-put technologies have generated a wealth of genomic data and made combining SNP and gene expression data become feasible., Results: In this paper, we propose a novel procedure to incorporate gene expression information into GWA analysis. This procedure utilizes weights constructed by gene expression measurements to adjust p values from a GWA analysis. RESULTS from simulation analyses indicate that the proposed procedures may achieve substantial power gains, while controlling family-wise type I error rates at the nominal level. To demonstrate the implementation of our proposed approach, we apply the weight adjustment procedure to a GWA study on serum interferon-regulated chemokine levels in systemic lupus erythematosus patients. The study results can provide valuable insights for the functional interpretation of GWA signals., Availability: The R source code for implementing the proposed weighting procedure is available at http://www.biostat.umn.edu/∼yho/research.html.

Objectives: The aim of this study was to measure, in early rheumatoid arthritis (RA) patients, the concentration of CC-chemokine ligand 19 (CCL19) in plasma and the cell-surface expression of CC-chemokine receptor 7 (CCR7) on circulating monocytes and CD4+ T lymphocytes and to analyse correlations with disease activity and 5-year radiographic progression., Method: In disease-modifying anti-rheumatic drug (DMARD)-naïve RA patients (disease duration < 6 months), we measured plasma CCL19 by enzyme-linked immunosorbent assay (ELISA) (n = 160) and CCR7 cell-surface expression on monocytes and CD4+ T lymphocytes by flow cytometry (n = 40) at baseline and after 1 year of treatment with methotrexate (MTX) or methotrexate+cyclosporin A (MTX/CyA). Radiographic progression was scored by the van der Heijde-modified Total Sharp Score (TSS) from 0 to 5 years., Results: Increased baseline CCL19 (median 85 pg/mL, range 31-1008 pg/mL, p = 0.01) decreased after 1 year (median 31 pg/mL, range 31-1030 pg/mL, p < 0.001) and 5 years (median 31 pg/mL, range 31-247 pg/mL, p < 0.001) to a level below the controls (n = 45) (median 60 pg/mL, range 31-152 pg/mL). Baseline plasma CCL19 levels [p = 0.011, 95% confidence interval (CI) 0.0030-0.0176], anti-cyclic citrullinated peptide (anti-CCP) antibody status (p = 0.002, 95% CI 0.61-2.38), and TSS > 0 at baseline (p < 0.001, 95% CI 1.21-3.16) were independent predictors of 5-year radiographic progression evaluated by multiple logistic regression in contrast to never smoked, C-reactive protein (CRP), gender, age, number of tender (NTJ) and swollen joints (NSJ), and 28-joint Disease Activity Score (DAS28). Increased CCR7 expression on monocytes (p = 0.008) correlated to CRP (p = 0.006, r = 0.52) and normalized (n = 15) after 1 year (p = 0.02)., Conclusions: In DMARD-naïve RA patients, CCL19 plasma level and CCR7 surface expression on monocytes were upregulated and normalized after 1 year of treatment. Increased baseline plasma CCL19 level, anti-CCP antibody status, and TSS > 0 at baseline correlated independently with 5-year radiographic progression.

Objective: Migration of B cells from peripheral blood to the synovium in patients with rheumatoid arthritis (RA) may predict clinical response to rituximab (RTX). We undertook this study to investigate whether serum levels of chemokines involved in B cell trafficking are correlated with blood levels of memory B cells or serum levels of B cell activation biomarkers before B cell depletion and whether chemokine levels predict RTX responsiveness., Methods: Blood B cell subsets were analyzed by flow cytometry (CD27, IgD), and serum B cell activation biomarkers (rheumatoid factor, anti-cyclic citrullinated peptide, free light chains, IgG, IgA, IgM, and BAFF) were measured in 208 RA patients and 70 control subjects. Serum CCL19, CXCL12, and CXCL13 chemokine levels in patients and controls were determined by enzyme-linked immunosorbent assay. The first course of RTX was administered to RA patients, and the response was evaluated at week 24 according to European League Against Rheumatism (EULAR) criteria. Results were expressed as the odds ratio (OR) and 95% confidence interval (95% CI)., Results: Levels of all chemokines were increased in RA patients compared with controls, and levels were inversely correlated with CD27+ memory B cell frequency. CCL19 and CXCL13 levels correlated with levels of 6 serum B cell biomarkers and 4 serum B cell biomarkers, respectively. By univariate analysis, the CCL19 level was positively associated with EULAR response (OR 1.43 [95% CI 1.08-1.90], P = 0.01). By multivariate analysis, the CCL19 level was predictive of a response to RTX (OR 1.48 [95% CI 1.06-2.06], P = 0.02), but this did not persist after adjustment for autoantibody status., Conclusion: CXCL13 and CCL19 reflect blood B cell disturbances and their levels correlate with those of other serum B cell biomarkers. CXCL13 and CCL19 are, therefore, surrogate measures for serum B cell biomarkers in RA. Serum CCL19 measurement is a new hallmark of the B cell-mediated RA subtype and may predict clinical response to RTX., (Copyright © 2013 by the American College of Rheumatology.)

Based on the ability to recruit lymphocytes and dendritic cells to lymphoid tissue and to promote inflammation, we hypothesized a role for dysregulated CCL19 and CCL21 levels in human immunodeficiency virus (HIV)-infected patients with advanced immunodeficiency, and in particular in those with accompanying Mycobacterium avium complex (MAC) infection. The hypothesis was explored by studies in HIV-infected patients with and without MAC infection, as well as in vitro, examining the ability of proteins from MAC to promote CCL19 and CCL21 responses in peripheral blood mononuclear cells (PBMC) during highly active anti-retroviral therapy (HAART). Our main findings were: (i) raised serum levels of CCL19 in HIV-infected patients with CD4(+) T cell count <50 cells/µl compared with HIV-infected patients with CD4(+) T cell count >500 cells/µl and healthy controls, with particularly high levels in those with MAC infection; (ii) elevated plasma levels of CCL19 predicted a higher mortality in acquired immune deficiency syndrome (AIDS)-patients, independent of ongoing MAC infection; and (iii) marked production of CCL19 in MAC-stimulated peripheral blood mononuclear cells (PBMC) and pronounced disturbances in MAC-induced CCL19 production in PBMC from HIV patients that was partly reversed during HAART. Our findings suggest the involvement of CCL19 in AIDS patients with advanced immunodeficiency, potentially mediating both adaptive and maladaptive responses., (© 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.)

Background: CCL19 and CCL21, acting through CCR7, are termed homeostatic chemokines. Based on their role in concerting immunological responses and their proposed involvement in tissue remodeling, we hypothesized that these chemokines could play a pathogenic role in heart failure (HF)., Methodology/principal Findings: Our main findings were: (i) Serum levels of CCL19 and particularly CCL21 were markedly raised in patients with chronic HF (n = 150) as compared with healthy controls (n = 20). A CCL21 level above median was independently associated with all-cause mortality. (ii) In patients with HF following acute myocardial infarction (MI; n = 232), high versus low CCL21 levels 1 month post-MI were associated with cardiovascular mortality, even after adjustment for established risk factors. (iii). Explanted failing human LV tissue (n = 29) had markedly increased expression of CCL21 as compared with non-failing myocardium (n = 5). (iv) Our studies in CCR7(-/-) mice showed improved survival and attenuated increase in markers of myocardial dysfunction and wall stress in post-MI HF after 1 week, accompanied by increased myocardial expression of markers of regulatory T cells. (v) Six weeks post-MI, there was an increase in markers of myocardial dysfunction and wall stress in CCR7 deficient mice., Conclusions/significance: High serum levels of CCL21 are independently associated with mortality in chronic and acute post-MI HF. Our findings in CCR7 deficient mice may suggest that CCL21 is not only a marker, but also a mediator of myocardial failure. However, while short term inhibition of CCR7 may be beneficial following MI, a total lack of CCR7 during long-term follow-up could be harmful.

Dendritic cells (DCs) are important mediators of the immune response against HIV and yet blood DC numbers fall substantially during HIV infection. Here we report that blood levels of the DC-tissue tropic chemokines monocyte chemotactic protein (MCP-1/CCL2), macrophage inflammatory proteins (MIP-3α/CCL20), and MIP-3β/CCL19 remained elevated throughout the course of HIV infection suggesting that the relatively low levels of blood circulating DCs may be due to active recruitment of these cells to peripheral sites to fight disease progression.

Our previous in vitro studies led to proposals that the atypical chemokine receptor CCX-CKR is a scavenger of CCR7 ligand homeostatic chemokines. In the present study, we generated CCX-CKR(-/-) mice and confirm this scavenger function in vivo. Compared with wild-type mice, CCX-CKR(-/-) have a 5-fold increase in the level of CCL21 protein in blood, and 2- to 3-fold increases in CCL19 and CCL21 in peripheral lymph nodes. The effect of these protein increases on immunity was investigated after immunization with MOG(35-55) peptide emulsified in complete Freund adjuvant (CFA). The subsequent characteristic paralysis develops with enhanced kinetics and severity in CCX-CKR(-/-) versus wild-type mice. Despite this effect, antigen-specific immune responses in the draining lymph nodes are diminished in CCX-CKR(-/-) mice. Instead, the earlier onset of disease is associated with enhanced T-cell priming in the CCX-CKR(-/-) spleen and a skewing of CD4(+) T-cell responses toward Th17 rather than Th1. This observation correlates with increased expression of IL-23 in the CCX-CKR(-/-) spleen and increased CCL21 levels in the central nervous system postimmunization. The early onset of disease in CCX-CKR(-/-) mice is reversed by systemic administration of neutralizing anti-CCL21 antibodies. Thus, by regulating homeostatic chemokine bioavailability, CCX-CKR influences the localization, kinetics, and nature of adaptive immune responses in vivo.

Background: The chemokine CXCL13 is known to dictate homing and motility of B cells in lymphoid tissue and has been implicated in the formation of ectopic lymphoid tissue in chronic inflammation. Whether it influences B cell trafficking during acute infection, is largely unclear. In previous studies, we showed that (I) CXCL13 levels are markedly increased in the B cell-rich cerebrospinal fluid (CSF) of patients with acute Lyme neuroborreliosis (LNB), and (II) CXCL13 is released by monocytes upon recognition of borrelial outer surface proteins by Toll-like receptor 2. Here, we assessed the role of CXCL13--in comparison to other chemokines--in the recruitment of B cells to the CSF of patients with acute LNB., Methods: Measurement of chemokines was done by ELISA. B cells were isolated from whole blood using magnetic cell separation (MACS). For migration experiments, a modified Boyden chamber assay was used and the migrated B cells were further analysed by FACS. The migration was inhibited either by preincubation of the CSF samples with neutralizing antibodies, heating to 60 degrees C, removal of proteins >3 kDa, or by pre-treatment of the B cells with pertussis toxin. The principal statistical tests used were one-way analysis of variance and Bonferroni test (chemokine measurements) as well as paired Student's t-test (migration experiments)., Results: Measurements of chemokine levels revealed an increase in three of the four known major B cell chemoattractants CXCL13, CCL19 and CXCL12 in LNB CSF. The CXCL13 CSF:serum ratio, as a measure of the chemotactic gradient, was substantially higher than that of CCL19 and CXCL12. Moreover, the chemotactic activity of LNB CSF was reduced up to 56% after preincubation with a neutralizing CXCL13 antibody, while combined preincubation with antibodies against CXCL13, CCL19, and CXCL12 did not lead to further reduction. Since treatment with pertussis toxin, heating to 60 degrees C, and removal of proteins >3 kDa abrogated the chemotactic activity, further not yet identified chemokines seem to be involved in B cell recruitment to LNB CSF., Conclusion: Combined, our study suggests a key role of CXCL13 in B cell migration to sites of infection as shown here for the CSF of LNB patients.

Objective: Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by unpredictable flares of disease activity and irreversible damage to multiple organ systems. An earlier study showed that SLE patients carrying an interferon (IFN) gene expression signature in blood have elevated serum levels of IFN-regulated chemokines. These chemokines were associated with more-severe and active disease and showed promise as SLE disease activity biomarkers. This study was designed to validate IFN-regulated chemokines as biomarkers of SLE disease activity in 267 SLE patients followed up longitudinally., Methods: To validate the potential utility of serum chemokine levels as biomarkers of disease activity, we measured serum levels of CXCL10 (IFNgamma-inducible 10-kd protein), CCL2 (monocyte chemotactic protein 1), and CCL19 (macrophage inflammatory protein 3beta) in an independent cohort of 267 SLE patients followed up longitudinally over 1 year (1,166 total clinic visits)., Results: Serum chemokine levels correlated with lupus activity at the current visit (P = 2 x 10(-10)), rising at the time of SLE flare (P = 2 x 10(-3)) and decreasing as disease remitted (P = 1 x 10(-3)); they also performed better than the currently available laboratory tests. Chemokine levels measured at a single baseline visit in patients with a Systemic Lupus Erythematosus Disease Activity Index of < or =4 were predictive of lupus flare over the ensuing year (P = 1 x 10(-4))., Conclusion: Monitoring serum chemokine levels in SLE may improve the assessment of current disease activity, the prediction of future disease flares, and the overall clinical decision-making.

The CCR7 ligands, CCL19 and CCL21, coordinate lymph node homing of naive and central memory T cells. In untreated HIV-infected patients, serum levels of CCL19 and CCL21 showed a biphasic pattern during progression; a marked increase was followed by a decline in patients with advanced immunodeficiency. During highly active antiretroviral therapy, a decrease in CCL19/CCL21 levels was restricted to virologic responders. We suggest that dysregulation of CCR7 ligands may play an important role in progression of HIV infection.