Machine Learning Identifies Key Proteins in Primary Sclerosing Cholangitis Progression and Links High CCL24 to Cirrhosis.

Primary sclerosing cholangitis (PSC) is a rare, progressive disease, characterized by inflammation and fibrosis of the bile ducts, lacking reliable prognostic biomarkers for disease activity. Machine learning applied to broad proteomic profiling of sera allowed for the discovery of markers of disease presence, severity, and cirrhosis and the exploration of the involvement of CCL24, a chemokine with fibro-inflammatory activity. Sera from 30 healthy controls and 45 PSC patients were profiled with proximity extension assay, quantifying the expression of 2870 proteins, and used to train an elastic net model. Proteins that contributed most to the model were tested for correlation to enhanced liver fibrosis (ELF) score and used to perform pathway analysis. Statistical modeling for the presence of cirrhosis was performed with principal component analysis (PCA), and receiver operating characteristics (ROC) curves were used to assess the useability of potential biomarkers. The model successfully predicted the presence of PSC, where the top-ranked proteins were associated with cell adhesion, immune response, and inflammation, and each had an area under receiver operator characteristic (AUROC) curve greater than 0.9 for disease presence and greater than 0.8 for ELF score. Pathway analysis showed enrichment for functions associated with PSC, overlapping with pathways enriched in patients with high levels of CCL24. Patients with cirrhosis showed higher levels of CCL24. This data-driven approach to characterize PSC and its severity highlights potential serum protein biomarkers and the importance of CCL24 in the disease, implying its therapeutic potential in PSC.

CCL24 Protects Renal Function by Controlling Inflammation in Podocytes.

Diabetic nephropathy (DN) is one of the most lethal complications of diabetes mellitus with chronic inflammation. We have examined the role of the inflammatory chemokine CCL24 in DN. We observed that serum levels of CCL24 were significantly elevated in patients with DN. Not only that, the expression of CCL24 was significantly increased in the kidneys of DN mice. The kidney of DN mice showed increased renal fibrosis and inflammation. We characterized an in vitro podocyte cell model with high glucose. Western blot analysis showed that expression of CCL24 was significantly increased under high-glucose conditions. Stimulation with high glucose (35 mmol/L) resulted in an increase in CCL24 expression in the first 48 hours but changed little after 72 hours. Moreover, with glucose stimulation, the level of podocyte fibrosis gradually increased, the expression of the proinflammatory cytokine IL-1ß was upregulated, and the expression of the glucose transporter GLUT4, involved in the insulin signal regulation pathway, also increased. It is suggested that CCL24 is involved in the pathogenesis of DN. In order to study the specific role of CCL24 in this process, we used the CRISPR-Cas9 technique to knock out CCL24 expression in podocytes. Compared with the control group, the podocyte inflammatory response induced by high glucose after CCL24 knockout was significantly increased. These results suggest that CCL24 plays a role in the development of early DN by exerting an anti-inflammatory effect, at least, in podocytes.

HbF Levels in Sickle Cell Disease Are Associated with Proportion of Circulating Hematopoietic Stem and Progenitor Cells and CC-Chemokines.

The concentration of circulating hematopoietic stem and progenitor cells has not been studied longitudinally. Here, we report that the proportions of Lin-CD34+38- hematopoietic multipotent cells (HMCs) and of Lin-CD34+CD38+ hematopoietic progenitors cells (HPCs) are highly variable between individuals but stable over long periods of time, in both healthy individuals and sickle cell disease (SCD) patients. This suggests that these proportions are regulated by genetic polymorphisms or by epigenetic mechanisms. We also report that in SCD patients treated with hydroxyurea, the proportions of circulating HMCs and HPCs show a strong positive and negative correlation with fetal hemoglobin (HbF) levels, respectively. Titration of 65 cytokines revealed that the plasma concentration of chemokines CCL2, CCL11, CCL17, CCL24, CCL27, and PDGF-BB were highly correlated with the proportion of HMCs and HPCs and that a subset of these cytokines were also correlated with HbF levels. A linear model based on four of these chemokines could explain 80% of the variability in the proportion of circulating HMCs between individuals. The proportion of circulating HMCs and HPCs and the concentration of these chemokines might therefore become useful biomarkers for HbF response to HU in SCD patients. Such markers might become increasingly clinically relevant, as alternative treatment modalities for SCD are becoming available.

Increased CCL24 and CXCL7 levels in the cerebrospinal fluid of patients with neurosyphilis.

BACKGROUND: Monocytes are recruited into the cerebrospinal fluid (CSF) of patients with neurosyphilis, suggesting abnormal chemokine expression. We aimed to investigate the aberrant expression of chemokines in the CSF of these patients. METHODS: CSF and serum samples were collected from patients with neurosyphilis between July 2017 and June 2019 in the Dermatology Department, Second Affiliated Hospital of Zhejiang University. Differences in the expression of 38 chemokines between patients with and without neurosyphilis were detected using RayBio® Human Chemokine Antibody Array C1. CCL24 and CXCL7 levels in the patients' CSF and serum were further measured using RayBio® CCL24 and CXCL7 ELISA kits. RESULTS: Ninety-three CSF and serum samples of patients with syphilis were collected. Antibody array analysis showed that the CSF levels of CCL24 (P = .0185), CXCL7 (P < .0001), CXCL13 (P < .0001), CXCL10 (P < .0001), and CXCL8 (P < .0001) were significantly higher in patients with than without neurosyphilis. ELISA confirmed significantly higher CCL24 and CXCL7 levels in the CSF of patients with than without neurosyphilis (CCL24: 6.082 ± 1.137 pg/mL vs 1.773 ± 0.4565 pg/mL, P = .0037; CXCL7: 664.3 ± 73.19 pg/mL vs 431.1 ± 90.54 pg/mL, P = .0118). Increased CCL24 and CXCL7 expression was seen throughout all neurosyphilis stages, had moderate diagnostic efficiency for neurosyphilis, and correlated poorly with CSF cell count and Venereal Disease Research Laboratory titer. CSF CCL24 levels also correlated poorly with CSF protein concentration. CONCLUSION: Abnormally high CSF chemokines levels may play a role in the pathogenesis of neurosyphilis.

Eotaxins and C-C chemokine receptor type 3 in Parkinson's disease.

Parkinson's disease (PD) is one of the most common neuroinflammatory disorders and inflammatory processes seem to play an important role in the pathogenesis of PD. Chemokines as inflammatory mediators, which are involved in the recruitment of leukocytes, can play a role in the pathogenesis of PD. The aim of this study was to examine the serum level of eotaxins (CCL11, CCL24, and CCL26) and the expression of C-C chemokine receptor type 3 (CCR3) in patients with PD compared with healthy subjects. In this study, we measured the serum levels of CCL11, CCL24, and CCL26 with ELISA. In addition, gene and protein expression of CCR3 were measured by RT-PCR and flow cytometry techniques in PD patients (n = 30) and age- and sex-matched healthy subjects (n = 30). All patients suffering from PD were assessed clinically through Unified Parkinson's Disease Rating Scale, Motor Examination (UPDRS ME). The results of this study showed that there was no significant alteration in the serum level of these chemokines and also their receptor among patients with PD and healthy subjects. No significant correlation was observed between the eotaxins serum levels and the clinical measures of PD severity. Based on the results, it can be concluded that eotaxins cannot be considered as appropriate targets for the diagnosis or treatment of PD.

IgG4 Related Autoimmune Pancreatitis: An Overview and the Emerging Role of Serum Eotaxin as a Potential Treatment Target.

BACKGROUND: Autoimmune pancreatitis (AIP) is a rare disease that has been classified into two subtypes. Type 1 is believed to be mediated by immunoglobulin G4 (IgG4) and type 2 is related to granulocytic epithelial lesions, but the pathogenetic mechanisms in both are still unknown. The patho-mechanism of AIP type 1 is suggested to be secondary to autoimmunity or allergy due to the increased serum IgG4 and immunoglobulin E levels, abundant infiltration of IgG4, plasmacytes and lymphocytes in the pancreas, and fibrosis. Both types of AIP respond to steroid treatment. The relapse rate after remission is high and reaches 30-50% within 6-12 months in AIP type 1; however, in AIP type 2 relapse is rare. The maintenance therapy and therapeutic strategy for relapsing patients with type 1 is managed with low dose steroids, however there are no consensus guidelines. In this review we discuss the current understanding of AIP, highlighting the emerging potential role of eotaxin in pathogenesis, classification, and management of the disease.

Association of CCL11, CCL24 and CCL26 with primary biliary cholangitis.

BACKGROUND: CCL11, CCL24 and CCL26 are potent chemokines for eosinophils. Since there has been no study reporting the association serum CCL11, CCL24 and CCL26 with fibrotic progression of PBC, the aim of this study is to explore the association. METHODS: One hundred and eight PBC patients, 52 patients with chronic hepatitis B (CHB) and 50 healthy controls (HC) were recruited. The sera were detected for CCL11, CCL24 and CCL26 using multiplex immunoassay. Other laboratory indicators were routinely measured. PBC was divided into four stages according to Scheuer's classification. RESULTS: Serum CCL11, CCL24 and CCL26 levels were significantly higher in PBC patients than those with CHB and HC (P < 0.05). The ROC analyses showed that all of the three CCLs performed well for identification of PBC (all P< or =0.001). The multiple linear regression analysis showed an independent relationship of CCL26 with APRI and FIB-4 in PBC patients, but no relationship of CCL11 and CCL24 with fibrotic indicators. Additionally, serum CCL11 and CCL26 were negatively correlated with histological stage of PBC, while serum CCL24 showed no statistical correlation. CONCLUSION: Serum CCL11, CCL24 and CCL26 are upregulated in PBC. CCL11 and CCL26 are associated with fibrotic progression of PBC, but CCL24 is not.

Elevated Levels of Eotaxin-2 in Serum of Fibromyalgia Patients.

FMS patients demonstrate an altered profile of chemokines relative to healthy controls (HC). Eotaxin-2 is a potent chemoattractant distributed in a variety of tissues. The aim of the study was to compare serum levels of eotaxin-2 between FMS patients and HC and to examine a potential correlation between eotaxin-2 levels and clinical parameters of FMS. Methods. 50 patients with FMS and 15 HC were recruited. Data on the severity of FMS symptoms and depression were collected. Serum levels of eotaxin-2 (ELISA) were determined in all participants. High-sensitive CRP (hs-CRP) was measured in the FMS group. Results. The FMS cohort included predominantly females (84%), mean age of 49, and mean disease duration of 6 years. FMS patients exhibited significantly higher eotaxin-2 levels (pg/ml) versus HC: 833 (±384) versus 622 (±149), p=0.04. Mean hs-CRP level among FMS patients was 4.8 ± 6 mg/l, a value not indicative of acute inflammation. No correlation was found between eotaxin-2 and hs-CRP levels. No correlation was found between eotaxin-2 and severity measures of FMS or depression. Conclusion. Eotaxin-2 does not appear to be a candidate for a disease activity biomarker in FMS. Further research is warranted into the role of this chemokine in the pathophysiology of the FMS.

Decreased epithelial and sputum miR-221-3p associates with airway eosinophilic inflammation and CXCL17 expression in asthma.

Airway eosinophilic inflammation is a key feature of type 2 high asthma. The role of epithelial microRNA (miR) in airway eosinophilic inflammation remains unclear. We examined the expression of miR-221-3p in bronchial brushings, induced sputum, and plasma from 77 symptomatic, recently diagnosed, steroid-naive subjects with asthma and 36 healthy controls by quantitative PCR and analyzed the correlation between miR-221-3p expression and airway eosinophilia. We found that epithelial, sputum, and plasma miR-221-3p expression was significantly decreased in subjects with asthma. Epithelial miR-221-3p correlated with eosinophil in induced sputum and bronchial biopsies, fraction of exhaled nitric oxide, blood eosinophil, epithelial gene signature of type 2 status, and methacholine provocative dosage required to cause a 20% decline in forced expiratory volume in the first second in subjects with asthma. Sputum miR-221-3p also correlated with airway eosinophilia and was partially restored after inhaled corticosteroid treatment. Inhibition of miR-221-3p expression suppressed chemokine (C-C motif) ligand (CCL) 24 (eotaxin-2), CCL26 (eotaxin-3), and periostin (POSTN) expression in BEAS-2B bronchial epithelial cells. We verified that chemokine (C-X-C motif) ligand (CXCL) 17, an anti-inflammatory chemokine, is a target of miR-221-3p, and epithelial CXCL17 expression significantly increased in asthma. CXCL17 inhibited CCL24, CCL26, and POSTN expression via the p38 MAPK pathway. Airway overexpression of miR-221-3p exacerbated airway eosinophilic inflammation, suppressed CXCL17 expression, and enhanced CCL24, CCL26, and POSTN expression in house dust mite-challenged mice. Taken together, epithelial and sputum miR-221-3p are novel biomarkers for airway eosinophilic inflammation in asthma. Decreased epithelial miR-221-3p may protect against airway eosinophilic inflammation by upregulating anti-inflammatory chemokine CXCL17.

Plasma levels of innate immune mediators are associated with liver fibrosis in low parasite burden Schistosoma mansoni-infected individuals.

In the murine model, it was demonstrated that pro-inflammatory cytokines and chemokines are essential to the formation and modulation of Schistosoma-induced granulomatous inflammation. However, the relationship of these immune mediators and disease severity is hard to be established in naturally infected individuals. The current study evaluates the association between plasma concentrations of MIF, sTNF-R1, CCL3, CCL7 and CCL24 and schistosomiasis morbidity in Schistosoma mansoni-infected patients with a low parasite burden. For this propose, 97 S. mansoni-infected individuals were subjected to abdominal ultrasound analysis and clinical examination. Among them, 88 had plasma concentration of immune mediators estimated by ELISA assay. Multivariate linear regression models were used to evaluate the relationship between the plasma concentration of immune mediators and the variables investigated. Although most individuals presented low parasite burden, over 30% of them showed signs of fibrosis defined by ultrasound measurements and 2 patients had a severe form of schistosomiasis. No association between parasite burden and the plasma levels of chemokine/cytokines or disease severity was observed. There was a positive association between plasma concentration of CCL4, sTNF-R1, CCL3 and MIF with gall bladder thickness and/or with portal vein thickness that are liver fibrosis markers. In contrast, no association was found between CCL7 plasma concentrations with any of the schistosomiasis morbidity parameters evaluated. The data showed that CCL24, sTNFR1, MIF and CCL3 can be detected in plasma of S. mansoni-infected individuals and their concentration would be used as prognostic makers of Schistosoma-induced liver fibrosis, even in individuals with low parasite burden.

An emerging role for eotaxins in neurodegenerative disease.

Eotaxins are C-C motif chemokines first identified as potent eosinophil chemoattractants. They facilitate eosinophil recruitment to sites of inflammation in response to parasitic infections as well as allergic and autoimmune diseases such as asthma, atopic dermatitis, and inflammatory bowel disease. The eotaxin family currently includes three members: eotaxin-1 (CCL11), eotaxin-2 (CCL24), and eotaxin-3 (CCL26). Despite having only ~30% sequence homology to one another, each was identified based on its ability to bind the chemokine receptor, CCR3. Beyond their role in innate immunity, recent studies have shown that CCL11 and related molecules may directly contribute to degenerative processes in the central nervous system (CNS). CCL11 levels increase in the plasma and cerebrospinal fluid of both mice and humans as part of normal aging. In mice, these increases are associated with declining neurogenesis and impaired cognition and memory. In humans, elevated plasma levels of CCL11 have been observed in Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, and secondary progressive multiple sclerosis when compared to age-matched, healthy controls. Since CCL11 is capable of crossing the blood-brain barrier of normal mice, it is plausible that eotaxins generated in the periphery may exert physiological and pathological actions in the CNS. Here, we briefly review known functions of eotaxin family members during innate immunity, and then focus on whether and how these molecules might participate in the progression of neurodegenerative diseases.

Anserine/Carnosine Supplementation Suppresses the Expression of the Inflammatory Chemokine CCL24 in Peripheral Blood Mononuclear Cells from Elderly People.

Our goal was to determine whether anserine/carnosine supplementation (ACS) suppresses chemokine levels in elderly people. In a double-blind randomized controlled trial, volunteers were assigned to the ACS or placebo group (1:1). Sixty healthy elderly volunteers (active, n = 30; placebo, n = 30) completed the study. The ACS group was administered 1.0 g of anserine/carnosine (3:1) for 3 months. A microarray analysis and subsequent quantitative real-time polymerase chain reaction (qRT-PCR) analysis of peripheral blood mononuclear cells (PBMCs) showed decreased expression of CCL24, an inflammatory chemokine (p < 0.05). Verbal memory, assessed using the Wechsler memory scale-logical memory, was preserved in the ACS group. An age-restricted sub-analysis showed significant verbal memory preservation by ACS in participants who were in their 60s (active, n = 12; placebo, n = 9; p = 0.048) and 70s (active, n = 7; placebo, n = 11; p = 0.017). The suppression of CCL24 expression was greatest in people who were in their 70s (p < 0.01). There was a significant correlation between the preservation of verbal memory and suppression of CCL24 expression in the group that was in the 70s (Poisson correlation, r = 0.46, p < 0.05). These results suggest that ACS may preserve verbal episodic memory, probably owing to CCL24 suppression in the blood, especially in elderly participants.

Two C-C Family Chemokines, Eotaxin and RANTES, Are Novel Independent Plasma Biomarkers for Abdominal Aortic Aneurysm.

BACKGROUND: Inflammation of the aortic wall is recognised as a key pathogenesis of abdominal aortic aneurysm (AAA). This study was undertaken to determine whether inflammatory cytokines could be used as biomarkers for the presence of AAA. METHODS AND RESULTS: Tissue profiles of 27 inflammatory cytokine were examined in AAA (n=14) and nonaneurysmal (n=14) aortic tissues. Three cytokines, regulated upon activation normally T-cell expressed and secreted (RANTES), eotaxin, and macrophage inflammatory protein 1 beta (MIP-1b), had increased expression in AAA, particularly within the adventitial layer of the aortic wall. Basic fibroblast growth factor (bFGF) had reduced expression in all layers of the AAA wall. Examination of the circulating plasma profiles of AAA (n=442) and AAA-free controls (n=970) suggested a (risk factor adjusted) AAA-association with eotaxin, RANTES, and high sensitivity C-reactive protein (hsCRP). A plasma inflammatory cytokine score, calculated using these three markers, suggested a strong risk association with AAA (odds ratio, 4.8; 95% CI, 3.5-6.7; P<0.0001), independent of age, sex, history of ischemic heart disease, and smoking. CONCLUSIONS: Contrary to reports suggesting a distinct T helper 2-associated inflammatory profile in AAA, this current study suggests a more-generalized pattern of inflammation, albeit with some potentially distinct features, including elevated plasma eotaxin and decreased plasma RANTES. In combination with hsCRP, these markers may have potential utility as AAA biomarkers.

Physiologic concentrations of HMGB1 have no impact on cytokine-mediated eosinophil survival or chemotaxis in response to Eotaxin-2 (CCL24).

HMGB1 is an alarmin that can stimulate the innate immune system alone or in a complex with other inflammatory mediators. Given the recent interest in HMGB1 with respect to the pathogenesis of eosinophil-associated disorders, including asthmatic inflammation and chronic rhinosinusitis, we have explored the role of this mediator and in promoting eosinophil activation. HMGB1 receptors RAGE and TLR4 but not TLR2 were detected on freshly isolated human eosinophils from healthy donors. Physiologic and relevant pathophysiologic levels of biologically-active HMGB1 had no effect on survival of human eosinophils alone or in combination with pro-survival cytokines IL-5, IL-3, or GM-CSF, and increasing concentrations of HMGB1 had no impact on surface expression of RAGE, TLR2 or TLR4. Similarly, HMGB1 did not elicit chemotaxis of human eosinophils alone and had no effect in combination with the eosinophil chemotactic agent, eotaxin-2 (CCL24). However, surface expression of TLR2 and TLR4 increased in response to cell stress, notably on eosinophils that remain viable after 48 hours without IL-5. As such, HMGB1 signaling on eosinophils may be substantially more detailed, and may involve complex immunostimulatory pathways other than or in addition to those evaluated here.

New biomarker for neovascular age-related macular degeneration: eotaxin-2.

Recently, eotaxin-CCR3 was reported to play an important role in choroidal neovascularization (CNV) development and was documented to be superior than vascular endothelial growth factor-A treatment when tested in CNV animals. As eotaxin studies are lacking in the human age-related macular degeneration (AMD) patients, we sought to determine whether eotaxin-2 (CCL24) has any association with inflammatory processes that occur in CNV. CCL24 levels were determined by enzyme linked immunosorbant assay (ELISA) after normalization to total serum protein and levels of ELISA were correlated to various risk factors in about 133 AMD patients and 80 healthy controls. The CCL24 levels were significantly higher in wet AMD patients as compared with dry AMD and normal controls. There was a significant difference when compared among wet AMD patients (i.e., minimally classic, predominantly classic, and occult). We also report significant difference in the CCL24 levels of Avastin-treated and untreated AMD patients. This study shows that CCL24 levels were found to be significantly increased in AMD patients despite Avastin treatment as compared with normal controls and those without Avastin, indicating that CCL24 may have an association with CNV and may be an important target to validate future therapeutic approaches in AMD in tandem with Avastin treatment.

Up-regulation of CCL11 and CCL26 is associated with activated eosinophils in bullous pemphigoid.

Eosinophils contribute to the pathogenesis of bullous pemphigoid (BP) by secretion of proinflammatory cytokines and proteases. Trafficking of eosinophils into tissue in animal models and asthma depends on interleukin-5 and a family of chemokines named eotaxins, comprising CCL11, CCL24 and CCL26. Up-regulation of CCL11 has been described in BP, but the expression of the other two members of the eotaxin-family, CCL24 and CCL26, has not been investigated. In addition to these chemokines, expression of adhesion molecules associated with eosinophil migration to the skin should be analysed. We demonstrate that similar to CCL11, the concentration of CCL26 was up-regulated in serum and blister fluid of BP patients. In contrast, the concentration of CCL24 was not elevated in sera and blister fluid of the same BP patients. In lesional skin, CCL11 and CCL26 were detected in epidermis and dermis by immunohistochemistry. In contrast to CCL11, CCL26 was expressed strongly by endothelial cells. In line with these findings, eosinophils represented the dominating cell population in BP lesional skin outnumbering other leucocytes. The percentage of eosinophils expressing very late antigen (VLA): VLA-4 (CD49d) and CD11c correlated with their quantity in tissue. Macrophage antigen (MAC)-1 (CD11b/CD18) was expressed constitutively by tissue eosinophils. In conclusion, these data link the up-regulation of the eosinophil chemotactic factor CCL26 in BP to the lesional accumulation of activated eosinophils in the skin. Thereby they broaden the understanding of BP pathogenesis and might indicate new options for therapeutic intervention.

Serum levels of chemokines in Parkinson's disease.

OBJECTIVE: Neuroinflammatory processes seem to contribute to the degeneration of dopaminergic neurons in Parkinson's disease (PD). Chemokines play a role in the pathogenesis of inflammatory diseases, acting mainly as mediators of leukocyte recruitment to inflammatory sites. The aim of the present study was to compare the serum levels of chemokines between healthy subjects and PD patients and to correlate these levels with the severity of PD. METHODS: We used ELISA to measure the levels of CCL3, CCL11, CCL24, CXCL8 and CXCL10 chemokines in the serum of PD patients (n = 47) and age- and gender-matched controls (n = 23). Patients were also clinically evaluated with the Unified Parkinson's Disease Rating Scale, the Modified Hoehn and Yahr Staging Scale and the Modified Schwab and England Activities of Daily Living Scale. RESULTS: There was no significant difference in serum levels of chemokines between controls and PD patients. There was no correlation between the serum levels of chemokines and the clinical measures of disease severity. CONCLUSIONS: These findings suggest that serum levels of chemokines may not be considered as potential biomarkers of PD.

Increased expression of chemokine receptor CCR3 and its ligands in ulcerative colitis: the role of colonic epithelial cells in in vitro studies.

Human colonic epithelial cells express T helper type 1 (Th1)-associated chemoattractants, yet little is known about the production of Th2-associated chemoattractants. CCL11/eotaxin-1, CCL24/eotaxin-2 and CCL26/eotaxin-3 are known to attract CCR3-expressing, Th2-polarized lymphocytes. We studied constitutive and inflammation-induced expression and production of CCR3 together with its ligands in the colon and peripheral blood of patients with inflammatory bowel disease (IBD) by flow cytometry, reverse transcription­polymerase chain reaction (RT­PCR) and enzyme-linked immunosorbent assay (ELISA). We further defined the regulated expression of these chemokines by RT­PCR and ELISA using cultured human epithelial cell lines. A higher fraction of peripheral T lymphocytes were found to be positive for CCR3 in patients with ulcerative colitis (UC) compared to Crohn's disease (CD), while almost no CCR3(+) T cells were found in normal controls (NC). Similarly, higher and more frequent expression of CCR3 was observed in colonic biopsies from patients with UC, regardless of the disease activity, when compared to CD or NCs. Serum CCL11/eotaxin-1 was increased significantly in UC (306 ± 87 pg/ml) and less so in CD (257 ± 43 pg/ml), whereas CCL24/eotaxin-2, and CCL26/eotaxin-3 were increased only in UC. Colonic expression of the three chemokines was minimal in NCs but high in inflammatory bowel diseases (especially UC) and was independent of disease activity. Th2, and to a lesser extent Th1, cytokines were able to induce expression and production of all three eotaxins from colonic epithelial cells in culture. CCR3 and ligands over-expression would appear to be a characteristic of UC. The production of CCR3 ligands by human colonic epithelial cells suggests further that epithelium can play a role in modulating pathological T cell-mediated mucosal inflammation.

Decreased levels of CCR3 in CD4+ lymphocytes of rheumatoid arthritis patients.

OBJECTIVES: To evaluate the expression of CCR3 receptors as well as CCR3 agonists, including eotaxin-2 and RANTES, among patients suffering from rheumatoid arthritis and healthy controls, as a possible pathogenetic mechanism in inflammatory joint disease. METHODS: Twenty-two patients and 13 healthy controls were recruited and clinically evaluated. CCR3 expression on CD4+ lymphocytes and mononuclear cells was evaluated by FACS analysis after staining with human CD4 APC (bioscience) and human CCR3 (CD193)PE. Levels of eotaxin-2 and RANTES were analysed by ELISA. RESULTS: A significant decrease was observed in the level of CD4+ cells expressing the CCR3 receptor in serum of RA patients (0.96+/-0.5) as compared with healthy controls (1.48+/-0.6) (p<0.05). A significant decrease in serum eotaxin-2 levels was evident among RA patients suffering from active disease, defined by a DAS-28 score above 5.5, compared with RA patients with lower activity scores (2.1+/-1.6 vs. 7.0+/-5.1; p=0.01). A significant decrease was evident in the number of CCR3 expressing Monocytes among RA patients treated with steroids and anti TNF-a medications as compared with RA patients not receiving such treatment. CONCLUSIONS: CCR3 is differentially expressed on inflammatory cells in RA, while eotaxin-2, a potent CCR3 agonist, is differentially expressed in active disease. Anti-inflammatory medications may down-regulate CCR3 expression in RA. The CCR3-CCR3 agonist pathway may thus have a pathogenic role in RA and may be a future target for novel treatment modalities.