Psoriasis is considered as a model for chronic immune-mediated disorders. Th17-cells are pivotal players in those diseases. Recently, we demonstrated that Th17-cells produce interleukin (IL)-29 and that IL-29 is highly present in psoriatic lesions. Whether IL-29, with its action on epithelial cells and melanocytes, contributes to psoriasis pathogenesis, was unknown so far. Analysis of IL-29-treated human keratinocytes revealed induction of the chemokines CXCL10, CXCL11, and, to a much lesser extent, CXCL9. Unlike these CXCR3A ligands, known to attract Th1-, CD8(+), NK-, and Th1/Th17 transient cells, no influence was found on chemokines attracting other immune cell populations or on molecules modulating the CXCR3A/CXCR3A ligand interaction. CXCR3A ligand expression was also induced by IL-29 in melanocytes and in epidermis models and explanted skin. Regarding other psoriasis-relevant cytokines, interferon-γ and, less potently, tumor necrosis factor-α and IL-1β shared and strengthened IL-29's capacity. Murine IL-29 counterpart injected into mouse skin provoked local CXCL10 and CXCL11 expression, T-cell infiltration, and, in consequence, skin swelling. The elevated IL-29 expression in psoriatic lesions was associated with upregulation of CXCR3A ligands compared to non-lesional skin of these patients and to the skin of healthy donors and atopic dermatitis patients, which lack IL-29 production. Importantly, neutralization of IL-29 reduced CXCR3A ligand levels in explant cultures of psoriatic lesions. Finally, elevated blood CXCL11 levels were found in psoriasis that might be useful for monitoring lesional activity of the IL-29 axis. In summary, the Th17-cytokine IL-29 induces specific chemokines and, in consequence, provokes skin infiltration of potentially pathogenic T-cells.

CONCLUSIONS

IL-29 selectively induces CXCR3A-binding chemokines (CXCL9, CXCL10, CXCL11) in skin cells. Murine IL-29 counterpart induces skin T-cell infiltration and inflammation in mice. CXCR3A ligands are IL-29-dependently increased in lesional skin of psoriasis patients. CXCR3A ligand levels in psoriatic skin correlate with epidermal T-cell numbers. Increased blood CXCL11 levels in psoriasis may be a biomarker for local IL-29 action.

OBJECTIVE

The chemokine receptor CXCR3 has been strongly related to inhibition of angiogenesis. The purpose of this study was to investigate the association between expression of CXCR3 on peripheral blood leukocytes and age-related wet macular degeneration. Furthermore, we measured the plasma concentration of chemokines CXCL9 to -11.

METHODS

The study group consisted of patients with age-related macular degeneration (AMD) attending our department. Patients referred for reasons other than AMD were enrolled as control subjects. The expression of CXCR3 on T cells and the plasma concentration of CXCL9 to -11 were measured using flow cytometry.

RESULTS

We looked at all CD8(+) T cells expressing CXCR3 and found a significantly lower percentage of these cells in the neovascular AMD group compared to the age-matched control group (P = 0.05). When dividing the CD8(+) cells into functional groups according to their expression of CXCR3, we found a significantly lower percentage of CD8(+) CXCR3(high) cells in the group with neovascular AMD compared to the control group (P = 0.038). We found a lower percentage of CD4(+)CD69(+)CXCR3(+) T cells in the group of patients with neovascular AMD when compared to the age-matched control group (P = 0.052).

CONCLUSIONS

Our results point toward a systemic dysregulation of CXCR3 in patients with neovascular AMD. Since there is evidence to suggest that CXCR3 is able to alter the response of VEGF, the primary driver of choroidal neovascularization (CNV) formation, low levels of CXCR3 could potentially drive some patients toward a more angiogenic profile leading to CNV formation and growth. CXCR3-enhancing molecules could therefore be a possible target for treatment of AMD.

The aim of this study was to identify inflammatory mediators of potential clinical relevance in synovial fluid (SF) samples of patients with knee osteoarthritis (OA). Therefore, radiographic OA severity, knee pain and function of 34 OA patients undergoing unicompartmental (UC) and bicompartmental (BC) knee arthroplasty were assessed prior to surgery and SF samples were analyzed for a broad variety of inflammatory mediators, including interleukins (ILs), interferons (IFNs), C-X-C motif ligand chemokines (CXCLs), and growth factors (nerve growth factor; NGF, vascular endothelial growth factor; VEGF, and stem cell growth factor β; SCGF-β) using multiplex assay. Significant differences were observed between the SF levels of different inflammatory markers. When compared to UC OA, significantly higher concentrations of IL-7, IL-8, IL-10, IL-12, IL-13, IFN-γ, VEGF and CXCL1 were detected in BC OA. Correlation analyses revealed significant associations between OA severity and IL-6, IL-8, IFN-γ, SCGF-β, VEGF, CXCL1. Interestingly, increases in both anti- (IL-10, IL-13) and pro-inflammatory (IL-7, IL-12, IFN-γ) cytokines, as well as growth factors (SCGF-β, VEGF), correlated significantly with the level of knee pain. Poorer knee function was associated with higher IL-6, IL-10, IL-12, IL-13, IL-18, βNGF, SCGF-β, VEGF and CXCL9 levels. In conclusion, this study provides an extensive profile of synovial inflammatory mediators in knee OA and identifies cytokines of potential clinical relevance. In fact, five of the mediators examined (IL-10, IL-12, IL-13, SCGF-β, VEGF) significantly correlate with both knee pain and function.

The aim of this study was to analyze the predictive value of CXCL9, CXCL10, and CXCL11 concentrations before and after 4 and 12 weeks of treatment with pegylated interferon-α2b and ribavirin in patients with chronic hepatitis C infected with the hepatitis C virus genotype 1. The study included 46 adult patients (29 women and 17 men). Chemokine quantification in the serum was performed at baseline and after 1, 3, and 6 months of treatment by enzyme immunoassay. Chemokine responses were compared in patients achieving a sustained virological response to treatment (SVR, n=26) and the non-SVR group (n=20). The differences in the CXCL9 and CXCL10 concentrations between the SVR and non-SVR groups were statistically significant. A multivariant analysis showed a significant association between treatment failure and higher concentrations of CXCL10. A higher predictive value of CXCL10 concentrations after 4 weeks of treatment compared to pretreatment values has been found (area under the curve 0.9288 and 0.7942, respectively, P=0.016). CXCL10 concentrations above 250 pg/mL 4 weeks after the start of treatment were independently associated with non-SVR. In conclusion, the results of this study have shown that CXCL10 concentrations at the time of a rapid viral response (4 weeks) are better predictors of achieving SVR compared to baseline levels. Additionally, this study suggests an important role of CXCL9 as a biomarker of SVR in patients with chronic hepatitis C.

OBJECTIVE

To describe the clinical manifestations of parainfluenza virus (PIV) infection and to characterize biochemical markers of PIV disease severity.

METHODS

We reviewed the medical records of 165 children who had a nasal wash culture positive for PIV at our institution between 1998 and 2008. Nasal wash samples were assayed for 26 inflammatory mediators using Luminex bead proteomics.

RESULTS

A total of 153 patients, ages 2 weeks to 12 years, with single virus infection were included in our final analysis. Fifty-two patients were infected with PIV1, 19 with PIV2, 74 with PIV3, and 8 with PIV4. Lower respiratory tract infection (LRTI) was diagnosed in 67 (44%) patients, 21 (14%) had laryngotracheobronchitis, and 49 (32%) had an upper respiratory infection other than laryngotracheobronchitis. LRTI was diagnosed in 54% of patients infected with PIV3, 35% of those infected with PIV1, 26% of those with PIV2, and 50% of those with PIV4. Compared with uninfected control patients, PIV-infected patients had higher nasal wash concentrations of interleukin-6, CX-chemokine ligand 8 (CXCL8 or interleukin-8), CCL3 (macrophage inflammatory protein-1alpha), CCL4 (macrophage inflammatory protein-1beta), CXCL9 (monokine induced by interferon gamma), and CCL5 (regulated upon activation, normal T cell expressed and secreted (RANTES). Patients with LRTI, moderate or severe illness, and PIV 1 or 3 (respirovirus) infection had higher nasal wash concentrations of CXCL8 when compared with patients with upper respiratory infection, mild illness, or PIV 2 and 4 (rubulavirus) infection (P < 0.05).

CONCLUSIONS

PIV infection causes a spectrum of illnesses associated with the expression and release of several proinflammatory mediators. Of note, elevated concentrations of CXCL8 in nasal wash samples are associated with more severe forms of PIV disease.

Chemokines are important mediators of the immune response that are responsible for the trafficking of immune cells between lymphoid organs and migration towards sites of inflammation.Using phage display selection and a functional screening approach, we have isolated a panel of single-chain fragment variable (scFv) capable of neutralizing the activity of the human chemokine CXCL10 (hCXCL10). One of the isolated scFv was weakly cross-reactive against another human chemokine CXCL9,but was unable to block its biological activity. We diversified the complementarity determining region 3 (CDR3) of the light chain variable domain (VL) of this scFv and combined phage display with high throughput antibody array screening to identify variants capable of neutralizing both chemokines. Using this approach it is therefore possible to engineer pan-specific antibodies that could prove very useful to antagonize redundant signaling pathways such as the chemokine signaling network.

Different immune effectors control distinct steps in tumor metastasis; T cells inhibit the growth of primary and metastatic tumors, while NK control tumor cells in transit. Vaccination with DNA encoding Her-2 which is expressed on primary and metastasized breast cancer cells induced both humoral and cellular immunity to inhibit tumor growth. Vaccination efficacy can be amplified by depleting CD4;+CD25;+Foxp3;+ regulatory T cells (Treg), but the risk of inducing autoimmunity warrants new strategies to selectively amplify anti-tumor immunity when modulating Treg. In the tumors, the major cyclooxygenase (COX)-2 product is prostaglandin E2(PGE2) which suppresses T and NK cells while amplifying Treg. These cellular responses to PGE2 are mediated through four E prostanoid (EP) receptors. Cox inhibitors and EP antagonists enhance NK activity to inhibit tumor metastasis; but they may down regulate MHC class I expression. Since T and NK cells have opposite requirements for MHC class I expression, their relative contribution to cancer control may vary with the stage of the disease. To enhance tumor infiltration by immune effectors, the role of CXCL9 is discussed. The complex nature of tumor metastasis necessitates a comprehensive approach to achieve successful immune intervention.

BACKGROUND

Ipilimumab is an antagonistic monoclonal antibody against cytotoxic T-lymphocyte antigen-4 (CTLA-4) that enhances antitumor immunity by inhibiting immunosuppressive activity of regulatory T cells (Treg). In this study, we investigated whether inhibiting Treg activity with ipilimumab during ex vivo T cell expansion could augment anti-CD3-driven T cell proliferation and enhance bispecific antibody (BiAb)-redirected antitumor cytotoxicity of activated T cells (ATC).

METHODS

PBMC from healthy individuals were stimulated with anti-CD3 monoclonal antibody with or without ipilimumab and expanded for 10-14 days. ATC were harvested and armed with anti-CD3 x anti-EGFR BiAb (EGFRBi) or anti-CD3 x anti-CD20 BiAb (CD20Bi) to test for redirected cytotoxicity against COLO356/FG pancreatic cancer cell line or Burkitt's lymphoma cell line (Daudi).

RESULTS

In PBMC from healthy individuals, the addition of ipilimumab at the initiation of culture significantly enhanced T cell proliferation (p = 0.0029). ATC grown in the presence of ipilimumab showed significantly increased mean tumor-specific cytotoxicity at effector:target (E:T) ratio of 25:1 directed at COLO356/FG and Daudi by 37.71% (p < 0.0004) and 27.5% (p < 0.0004), respectively, and increased the secretion of chemokines (CCL2, CCL3, CCL4,CCL5, CXCL9, and granulocyte-macrophage colony stimulating factor(GM-CSF)) and cytokines (IFN-γ, IL-2R, IL-12, and IL-13), while reducing IL-10 secretion.

CONCLUSIONS

Expansion of ATC in the presence of ipilimumab significantly improves not only the T cell proliferation but it also enhances cytokine secretion and the specific cytotoxicity of T cells armed with bispecific antibodies.

Aquaporin-1 (AQP1) has been associated with tumor development. Here, we investigated how AQP1 may affect cell proliferation. The proliferative rate of adult carotid body (CB) cells, known to proliferate under chronic hypoxia, was analyzed in wild-type (AQP1(+/+) ) and knock out (AQP1(-/-) ) mice, maintained in normoxia or exposed to hypoxia while BrdU was administered. Fewer numbers of total BrdU(+) and TH-BrdU(+) cells were observed in AQP1(-/-) mice, indicating a role for AQP1 in CB proliferation. Then, by flow cytometry, cell cycle state and proliferation of cells overexpressing AQP1 were compared to those of wild-type cells. In the AQP1-overexpressing cells, we observed higher cell proliferation and percentages of cells in phases S and G2/M and fewer apoptotic cells after nocodazole treatment were detected by annexin V staining. Also in these cells, proteomic assays showed higher expression of cyclin D1 and E1 and microarray analysis revealed changes in many cell proliferation-related molecules, including, Zeb 2, Jun, NF-kβ, Cxcl9, Cxcl10, TNF, and the TNF receptor. Overall, our results indicate that the presence of AQP1 modifies the expression of key cell cycle proteins apparently related to increases in cell proliferation. This contributes to explaining the presence of AQP1 in many different tumors.

The cyclin D1 gene encodes the regulatory subunit of a holoenzyme that drives cell autonomous cell cycle progression and proliferation. Herein we show cyclin D1 abundance is increased >30-fold in the stromal fibroblasts of patients with invasive breast cancer, associated with poor outcome. Cyclin D1 transformed hTERT human fibroblast to a cancer-associated fibroblast phenotype. Stromal fibroblast expression of cyclin D1 (cyclin D1Stroma) in vivo, enhanced breast epithelial cancer tumor growth, restrained apoptosis, and increased autophagy. Cyclin D1Stroma had profound effects on the breast tumor microenvironment increasing the recruitment of F4/80+ and CD11b+ macrophages and increasing angiogenesis. Cyclin D1Stroma induced secretion of factors that promoted expansion of stem cells (breast stem-like cells, embryonic stem cells and bone marrow derived stem cells). Cyclin D1Stroma resulted in increased secretion of proinflammatory cytokines (CCL2, CCL7, CCL11, CXCL1, CXCL5, CXCL9, CXCL12), CSF (CSF1, GM-CSF1) and osteopontin (OPN) (30-fold). OPN was induced by cyclin D1 in fibroblasts, breast epithelial cells and in the murine transgenic mammary gland and OPN was sufficient to induce stem cell expansion. These results demonstrate that cyclin D1Stroma drives tumor microenvironment heterocellular signaling, promoting several key hallmarks of cancer.

The immunosuppressive properties of mesenchymal stromal/stem cells (MSC) rendered them an attractive therapeutic approach for immune disorders and an increasing body of evidence demonstrated their clinical value. However, the influence of MSC on the function of specific immune cell populations, namely, monocyte subpopulations, is not well elucidated. Here, we investigated the influence of human bone marrow MSC on the cytokine and chemokine expression by peripheral blood classical, intermediate and nonclassical monocytes, and myeloid dendritic cells (mDC), stimulated with lipopolysaccharide plus interferon (IFN)γ. We found that MSC effectively inhibit tumor necrosis factor- (TNF-) α and macrophage inflammatory protein- (MIP-) 1β protein expression in monocytes and mDC, without suppressing CCR7 and CD83 protein expression. Interestingly, mDC exhibited the highest degree of inhibition, for both TNF-α and MIP-1β, whereas the reduction of TNF-α expression was less marked for nonclassical monocytes. Similarly, MSC decreased mRNA levels of interleukin- (IL-) 1β and IL-6 in classical monocytes, CCL3, CCL5, CXCL9, and CXCL10 in classical and nonclassical monocytes, and IL-1β and CXCL10 in mDC. MSC do not impair the expression of maturation markers in monocytes and mDC under our experimental conditions; nevertheless, they hamper the proinflammatory function of monocytes and mDC, which may impede the development of inflammatory immune responses.

Chemokines recruit and activate leukocytes, assisting granuloma formation. Herein, we evaluated plasma chemokines in patients with active tuberculosis (ATB) and after completing treatment (TTB) and compared them to BCG-vaccinated healthy controls (HC). Levels of chemokines were measured by cytometric bead array. Levels of CXCL8, CXCL9 and CXCL10 were higher in ATB patients compared to HC, but they decreased in TTB. Levels of CCL2 and CCL5 in ATB patients were similar to those observed in HC. Thus, the high levels of CXC-chemokines detected during ATB, which can modulate the trafficking of immune cells from the periphery to the site of infection, were reversed by anti-mycobacterial treatment.

Mycobacterium bovis bacille Calmette-Guérin (BCG) is listed as an intralesional (IL) therapeutic option for inoperable stage III in-transit melanoma in the National Comprehensive Cancer Network Guidelines. Although the mechanism is unknown, others have reported up to 50% regression of injected lesions, and 17% regression of uninjected lesions in immunocompetent patients after direct injection of BCG into metastatic melanoma lesions in the skin. BCG and other mycobacteria express ligands capable of stimulating the γ9δ2 T cells. Therefore, we hypothesized that γ9δ2 T cells play a role in promoting BCG-mediated antitumor immunity in patients treated with IL-BCG for in-transit cutaneous melanoma metastases. Indeed, we found γ9δ2 T cell infiltration in melanoma skin lesions during the course of IL-BCG treatment. Gene expression analysis revealed that BCG injection elicits the expression of a vast array of chemokines in tumor lesions, including strong expression of CXCL9, 10, and 11, a set of chemokines that attract T cells expressing the CXCR3 chemokine receptor. In corroboration with our hypothesis, approximately 85% of γδ T cells express high levels of CXCR3 on their surface. Importantly, the injected tumor lesions also express genes whose protein products are the antigenic ligands for γδ T cells (BTN3A1 and MICB), and the cytokines that are the typical products of activated γδ T cells. Interestingly, we also found that γδ T cells infiltrate the regressed lesions that did not receive BCG injections. Our study suggests that γ9δ2 T cells may contribute to melanoma regression induced by IL-BCG treatment.

UNASSIGNED

Pregnancy malaria (PM) is associated with a proinflammatory immune response characterized by increased levels of cytokines and chemokines such as tumor necrosis factor-α, interferon-γ, interleukin 10 (IL-10), and CXCL9. These changes are associated with poor outcomes including low birthweight delivery and maternal anemia. However, it is unknown if inflammatory pathways during malaria are related to pregnancy loss and preterm delivery (PTD).

UNASSIGNED

Cytokine and chemokine levels were measured in maternal peripheral blood at enrollment, gestational week 30-32, and delivery, and in placental blood, of 638 women during a longitudinal cohort study in Ouelessebougou, Mali. Plasmodium falciparum infection was assessed by blood smear microscopy at all visits.

UNASSIGNED

PM was associated with increased levels of cytokines and chemokines including IL-10 and CXCL9. In a competing risks model adjusted for known covariates, high CXCL9 levels measured in the peripheral blood during pregnancy were associated with increased risk of pregnancy loss and PTD. At delivery, high IL-10 levels in maternal blood were associated with an increase in pregnancy loss, and increased IL-1β levels in placental blood were associated with pregnancy loss and PTD.

UNASSIGNED

PM is associated with increased proinflammatory cytokine and chemokine levels in placental and maternal peripheral blood. Systemic inflammatory responses to malaria during pregnancy predict increased risk of pregnancy loss and PTD.

UNASSIGNED

NCT01168271.

BACKGROUND

Debate about the potential effects that surgery might have on cancer cells dormancy and angiogenesis prompted us to investigate the impact of breast surgery on circulating angiogenesis modulating gene transcripts and proteins.

METHODS

Blood samples from 10 female patients diagnosed with breast cancer and 6 with fibroadenoma were collected before surgery and post-operatively on days 3 and 7 (breast cancer patients only). A set of 84 angiogenesis-associated transcripts were assessed using quantitative PCR arrays, and circulating protein levels (vascular endothelial growth factor A (VEGFA), IL8 and fibroblast growth factor 2 (FGF2) were measured using ELISA in the same samples. The results were investigated against clinicopathological data and patient outcome.

RESULTS

Plasma levels of VEGFA and IL8 after surgery were significantly elevated in the breast cancer group compared to the control group (P = 0.038 and P = 0.021, respectively). In the cohort of breast cancer patients, VEGFA increased on day 3 (P = 0.038) and declined on day 7 (P= 0.017), while IL8 did not change on day 3 but showed a significant decline on day 7 (P = 0.02). FGF2 levels did not change significantly over time. Regarding gene transcripts, we detected upregulation of a significant number of angiogenesis-specific genes in patients with breast cancer versus controls: sphingosine kinase 1(SPHK1), epidermal growth factor (EGF), vascular endothelial growth factor C (VEGFC), neuropilin 1 (NRP1), fibroblast growth factor (FGF1), laminin alpha 5 (LAMA5), collagen type IV alpha 3 (COL4A3), IL8, ephrin B2 (EFNB2), ephrin A3 (EFNA3), tyrosine endothelial kinase (TEK), integrin beta 3 (ITGB3), AKT1, thrombospondin 1 (THBS1), chemokine (C-C motif) ligand 11 (CCL11) and TIMP metallopeptidase inhibitor 3 (TIMP3). Surgery induced an altered expression in several keygenes in breast cancer patients. We identified an upregulation of COL4A3 and downregulation of chemokine (C-X-C motif) ligand 9 (CXCL9), EGF, FGF1, Kinase insert domain receptor (KDR), Placental growth factor (PGF), TIMP3 and VEGFC.

CONCLUSIONS

Breast cancer patients have a different expression profile of circulating angiogenesis biomarkers compared to patients with fibroadenoma. Moreover, mastectomy promotes a transient increase of VEGFA and a shift in the expression patterns of a broad panel of angiogenesis-related circulating gene transcripts.

OBJECTIVE

Chemokines, such as CXCR3-ligands, have been identified to play an important role during hepatic injury, inflammation and fibrosis. While CXCL9 is associated with survival in patients receiving transjugular intrahepatic portosystemic shunt (TIPS), the role of CXCL11 in severe portal hypertension remains unknown.

METHODS

CXCL11-levels were measured in 136 patients with liver diseases, and 63 healthy controls. In further 47 cirrhotic patients receiving TIPS, CXCL11 levels were measured in portal and hepatic veins at TIPS insertion by cytometric bead array. CXCL11-levels were measured in 23 patients in cubital vein and right atrium, whereas in 24 patients in portal and hepatic blood at an invasive reevaluation.

RESULTS

CXCL11-levels were increased with the severity of liver fibrosis. CXCL11-levels from portal, hepatic and cubital veins and right atrium showed a highly significant correlation among each other in these patients. Furthermore, levels of CXCL11 from the right atrium were significantly higher than those from cubital vein. Interestingly, patients with alcoholic cirrhosis had significantly lower CXCL11-levels, than other aetiologies of cirrhosis. After TIPS, CXCL11 levels correlated with the degree of portal pressure and patients with higher CXCL11-levels in portal and hepatic veins showed higher mortality. Multivariate analysis revealed hepatic CXCL11-levels before TIPS, creatinine and age as independent predictors for survival in TIPS patients, whereas MELD score and low portal CXCL11-levels after TIPS predicted long-term survival.

CONCLUSIONS

CXCL11 levels are mainly increased in patients with non-alcoholic cirrhosis and high portal pressure. Moreover, levels of CXCL11 might predict long-time survival of cirrhotic patients bearing TIPS.

OBJECTIVE

Inflammation, collagen deposition and tissue remodelling are involved in the pathogenesis and complications of cirrhosis with portal hypertension. CXCL9 and other chemokines play an important role in these processes and have been associated with liver injury and complications of liver disease in humans. However, their predictive value in patients with cirrhosis and portal hypertension remains to be established.

METHODS

103 patients with liver cirrhosis who had received TIPS (transjugular intrahepatic portosystemic shunt) were included into this study. The TIPS indication was either refractory ascites or recurrent bleeding. Before and after the TIPS procedure portal and hepatic venous blood samples were obtained in 78 patients. In 25 patients blood samples were obtained from the portal vein, hepatic vein, right atrium and cubital vein at TIPS insertion. Serum levels of CXCL9 were measured by cytometric bead array and correlated with clinical parameters and overall outcome.

RESULTS

Portal venous levels of CXCL9 decreased after TIPS. Child-Pugh score, refractory ascites, renal dysfunction and alcoholic aetiology of cirrhosis were associated with increased CXCL9 levels. Importantly, low levels of CXCL9 in portal and hepatic vein samples were prognostic factors for the survival of patients receiving TIPS during long-time follow-up.

CONCLUSIONS

The CXCR3 ligand CXCL9 affects the liver and/or is released by the liver and thereby might contribute to hepatic and extrahepatic organ dysfunction. Elevated levels of CXCL9 are associated with shorter survival in cirrhotic patients with severe portal hypertension receiving TIPS. This chemokine should be further evaluated as a novel biomarker for the outcome in patients with cirrhosis and portal hypertension and its modulation as a new therapeutic strategy.

Bone marrow-derived myeloid cells can form a premetastatic niche and provide a tumor-promoting microenvironment. However, subsets of myeloid cells have also been reported to have anti-tumor properties. It is not clear whether there is a transition between anti- and pro- tumor function of these myeloid cells, and if so, what are the underlying molecular mechanisms. Here we report platelet factor 4 (PF4), or CXCL4, but not the other family members CXCL9, 10, and 11, was produced at higher levels in the normal lung and early stage premetastatic lungs but decreased in later stage lungs. PF4 was mostly produced by Ly6G+CD11b+ myeloid cell subset. Although the number of Ly6G+CD11b+ cells was increased in the premetastatic lungs, the expression level of PF4 in these cells was decreased during the metastatic progression. Deletion of PF4 (PF4 knockout or KO mice) led an increased metastasis suggesting an inhibitory function of PF4. There were two underlying mechanisms: decreased blood vessel integrity in the premetastatic lungs and increased production of hematopoietic stem/progenitor cells (HSCs) and myeloid derived suppressor cells (MDSCs) in tumor-bearing PF4 KO mice. In cancer patients, PF4 expression levels were negatively correlated with tumor stage and positively correlated with patient survival. Our studies suggest that PF4 is a critical anti-tumor factor in the premetastatic site. Our finding of PF4 function in the tumor host provides new insight to the mechanistic understanding of tumor metastasis.

The peripheral blood (PB) monocyte pool contains osteoclast progenitors (OCPs), which contribute to osteoresorption in inflammatory arthritides and are influenced by the cytokine and chemokine milieu. We aimed to define the importance of chemokine signals for migration and activation of OCPs in rheumatoid arthritis (RA) and psoriatic arthritis (PsA).

PB and, when applicable, synovial fluid (SF) samples were collected from 129 patients with RA, 53 patients with PsA, and 110 control patients in parallel to clinical parameters of disease activity, autoantibody levels, and applied therapy. Receptors for osteoclastogenic factors (CD115 and receptor activator of nuclear factor-κB [RANK]) and selected chemokines (CC chemokine receptor 1 [CCR1], CCR2, CCR4, CXC chemokine receptor 3 [CXCR3], CXCR4) were determined in an OCP-rich subpopulation (CD3-CD19-CD56-CD11b+CD14+) by flow cytometry. In parallel, levels of CC chemokine ligand 2 (CCL2), CCL3, CCL4, CCL5, CXC chemokine ligand 9 (CXCL9), CXCL10, and CXCL12 were measured using cytometric bead array or enzyme-linked immunosorbent assay. Sorted OCPs were stimulated in culture by macrophage colony-stimulating factor and receptor activator of nuclear factor-κB ligand, and they were differentiated into mature osteoclasts that resorb bone. Selected chemokines (CCL2, CCL5, CXCL10, and CXCL12) were tested for their osteoclastogenic and chemotactic effects on circulatory OCPs in vitro.

The OCP population was moderately enlarged among PB cells in RA and correlated with levels of tumor necrosis factor-α (TNF-α), rheumatoid factor, CCL2, and CCL5. Compared with PB, the RANK+ subpopulation was expanded in SF and correlated with the number of tender joints. Patients with PsA could be distinguished by increased RANK expression rather than total OCP population. OCPs from patients with arthritis had higher expression of CCR1, CCR2, CCR4, CXCR3, and CXCR4. In parallel, patients with RA had increased levels of CCL2, CCL3, CCL4, CCL5, CXCL9, and CXCL10, with significant elevation in SF vs PB for CXCL10. The subset expressing CXCR4 positively correlated with TNF-α, bone resorption marker, and rheumatoid factor, and it was reduced in patients treated with disease-modifying antirheumatic drugs. The CCR4+ subset showed a significant negative trend during anti-TNF treatment. CCL2, CCL5, and CXCL10 had similar osteoclastogenic effects, with CCL5 showing the greatest chemotactic action on OCPs.

In our study, we identified distinct effects of selected chemokines on stimulation of OCP mobilization, tissue homing, and maturation. Novel insights into migratory behaviors and functional properties of circulatory OCPs in response to chemotactic signals could open ways to new therapeutic targets in RA.

Adverse local tissue reactions (ALTR) associated with tribocorrosion following total hip arthroplasty (THA) have become a significant clinical concern in recent years. In particular, implants featuring metal-on-metal bearing surfaces and modular femoral stems have been reported to result in elevated rates of ALTR. These tribocorrosion-related tissue reactions are characterized by marked necrosis and lymphocytic infiltration, which contrasts sharply with the macrophagic and foreign body giant cell inflammation associated with polyethylene wear particle induced peri-implant osteolysis. In this study, we characterize tribocorrosion-associated ALTR at a molecular level. Gene expression profiling of peri-implant tissue around failing implants identifies upregulation of numerous inflammatory mediators in ALTR, including several interferon gamma inducible factors, most notably the chemokines MIG/CXCL9 and IP-10/CXCL10. This expression profile is distinct from that associated with polyethylene wear induced osteolysis, which is characterized by induction of markers of alternative macrophage activation, such as chitotriosidase (CHIT-1). Importantly, MIG/CXCL9 and IP-10/CXCL10 are also elevated at the protein level in the synovial fluid and, albeit more moderately, the serum, of ALTR patients, raising the possibility that these factors may serve as circulating biomarkers for the early detection of ALTR in at-risk patients.

Biomarkers are increasingly used for diagnosis and treatment of transplant-related complications including the first biomarker-driven interventional trials of acute graft-versus-host disease (GvHD). In contrast, the development of biomarkers of chronic GvHD (cGvHD) has lagged behind due to a broader variety of manifestations, overlap with acute GvHD, a greater variation in time to onset and maximum severity, and lack of sufficient patient numbers within prospective trials. An international workshop organized by a North-American and European consortium was held in Marseille in March 2017 with the goal to discuss strategies for future biomarker development to guide cGvHD therapy. As a result of this meeting, two areas were prioritized: the development of prognostic biomarkers for subsequent onset of moderate/severe cGvHD, and in parallel, the development of qualified clinical-grade assays for biomarker quantification. The most promising prognostic serum biomarkers are CXCL9, ST2, matrix metalloproteinase-3, osteopontin, CXCL10, CXCL11, and CD163. Urine-proteomics and cellular subsets (CD4+ T-cell subsets, NK cell subsets, and CD19+CD21low B cells) represent additional potential prognostic biomarkers of cGvHD. A joint effort is required to verify the results of numerous exploratory trials before any of the potential candidates is ready for validation and subsequent clinical application.

The compound 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an environmental contaminant, is a potent ligand for aryl hydrocarbon receptor (AhR). In the current study, we made an exciting observation that naive C57BL/6 mice that were exposed i.p. to TCDD showed massive mobilization of myeloid-derived suppressor cells (MDSCs) in the peritoneal cavity. These MDSCs were highly immunosuppressive and attenuated Con A-induced hepatitis upon adoptive transfer. TCDD administration in naive mice also led to induction of several chemokines and cytokines in the peritoneal cavity and serum (CCL2, CCL3, CCL4, CCL11, CXCL1, CXCL2, CXCL5, CXCL9, G-CSF, GM-CSF, VEGF, and M-CSF) and chemokine receptors on MDSCs (CCR1, CCR5, and CXCR2). Treatment with CXCR2 or AhR antagonist in mice led to marked reduction in TCDD-induced MDSCs. TCDD-induced MDSCs had high mitochondrial respiration and glycolytic rate and exhibited differential microRNA (miRNA) expression profile. Specifically, there was significant downregulation of miR-150-5p and miR-543-3p. These two miRNAs targeted and enhanced anti-inflammatory and MDSC-regulatory genes, including IL-10, PIM1, ARG2, STAT3, CCL11 and its receptors CCR3 and CCR5 as well as CXCR2. The role of miRs in MDSC activation was confirmed by transfection studies. Together, the current study demonstrates that activation of AhR in naive mice triggers robust mobilization of MDSCs through induction of chemokines and their receptors and MDSC activation through regulation of miRNA expression. AhR ligands include diverse compounds from environmental toxicants, such as TCDD, that are carcinogenic to dietary indoles that are anti-inflammatory. Our studies provide new insights on how such ligands may regulate health and disease through induction of MDSCs.