Serum CCL7 Is a Novel Prognostic Biomarker of Metastatic Colorectal Cancer.

BACKGROUND/AIM: Colorectal cancer is the third most common cancer globally, and the poor prognosis of patients with metastatic colorectal cancer (mCRC) warrants urgent attention. We previously obtained 10 candidate serum biomarkers for mCRC. Our aim with this study was to determine the prognostic performance of the pre-treatment serum C-C motif chemokine ligand 7 (CCL7) concentration in patients with mCRC. PATIENTS AND METHODS: Protein concentrations of CCL7 were examined using ELISA and immunohistochemistry for serum (n=110) and surgical specimens (n=85), respectively, of patients with mCRC. The relationship between protein concentration and prognosis was examined using Cox regression analysis, receiver operator characteristic curve analysis and the Kaplan-Meier method. RESULTS: The overall survival (OS) of patients with high concentrations of serum CCL7 was significantly poorer than that of patients with low concentrations. Patients with a high CCL7 concentration in the stroma had significantly poorer outcomes than those with a low concentration. The concentrations of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 were significantly higher in the high-CCL7 group, compared to those in the low-CCL7 group. Univariate and multivariate analysis revealed that serum CCL7 concentration was a significant prognostic factor for mCRC. The combination of serum CCL and CEA concentrations was also useful in this regard (area under the curve=0.71). CONCLUSION: The combined pre-treatment serum levels of CCL7 and CEA are useful prognostic biomarkers for mCRC.

The increased intrathecal expression of the monocyte-attracting chemokines CCL7 and CXCL12 in tick-borne encephalitis.

Tick-borne encephalitis (TBE) is a relatively severe and clinically variable central nervous system (CNS) disease with a significant contribution of a secondary immunopathology. Monocytes/macrophages play an important role in the CNS inflammation, but their pathogenetic role and migration mechanisms in flavivirus encephalitis in humans are not well known. We have retrospectively analyzed blood and cerebrospinal fluid (CSF) monocyte counts in 240 patients with TBE presenting as meningitis (n = 110), meningoencephalitis (n = 114), or meningoencephalomyelitis (n = 16), searching for associations with other laboratory parameters, clinical presentation, and severity. We have measured concentrations of selected monocytes-attracting chemokines (CCL7, CXCL12, CCL20) in serum and CSF of the prospectively recruited patients with TBE (n = 15), with non-TBE aseptic meningitis (n = 6) and in non-infected controls (n = 8). The data were analyzed with non-parametric tests, p < 0.05 considered significant. Monocyte CSF count correlated with other CSF inflammatory parameters, but not with the peripheral monocytosis, consistent with an active recruitment into CNS. The monocyte count did not correlate with a clinical presentation. The median CSF concentration of CCL7 and CXCL12 was increased in TBE, and that of CCL7 was higher in TBE than in non-TBE meningitis. The comparison of serum and CSF concentrations pointed to the intrathecal synthesis of CCL7 and CXCL12, but with no evident concentration gradients toward CSF. In conclusion, the monocytes are recruited into the intrathecal compartment in concert with other leukocyte populations in TBE. CCL7 and CXCL12 have been found upregulated intrathecally but are not likely to be the main monocyte chemoattractants.

Associations of Adiposity, Circulating Protein Biomarkers, and Risk of Major Vascular Diseases.

Importance: Obesity is associated with a higher risk of cardiovascular disease (CVD), but little is known about the role that circulating protein biomarkers play in this association. Objective: To examine the observational and genetic associations of adiposity with circulating protein biomarkers and the observational associations of proteins with incident CVD. Design, Setting, and Participants: This subcohort study included 628 participants from the prospective China Kadoorie Biobank who did not have a history of cancer at baseline. The Olink platform measured 92 protein markers in baseline plasma samples. Data were collected from June 2004 to January 2016 and analyzed from January 2019 to June 2020. Exposures: Measured body mass index (BMI) obtained during the baseline survey and genetically instrumented BMI derived using 571 externally weighted single-nucleotide variants. Main Outcomes and Measures: Cross-sectional associations of adiposity with biomarkers were examined using linear regression. Associations of biomarkers with CVD risk were assessed using Cox regression among those without prior cancer or CVD at baseline. Mendelian randomization was conducted to derive genetically estimated associations of BMI with biomarkers. Findings: In observational analyses of 628 individuals (mean [SD] age, 52.2 [10.5] years; 385 women [61.3%]), BMI (mean [SD], 23.9 [3.6]) was positively associated with 27 proteins (per 1-SD higher BMI; eg, interleukin-6: 0.21 [95% CI, 0.12-0.29] SD; interleukin-18: 0.13 [95% CI, 0.05-0.21] SD; monocyte chemoattractant protein-1: 0.12 [95% CI, 0.04-0.20] SD; hepatocyte growth factor: 0.31 [95% CI, 0.24-0.39] SD), and inversely with 3 proteins (Fas ligand: -0.11 [95% CI, -0.19 to -0.03] SD; TNF-related weak inducer of apoptosis, -0.14 [95% CI, -0.23 to -0.06] SD; and carbonic anhydrase 9: (-0.14 [95% CI, -0.22 to -0.05] SD), with similar associations identified for other adiposity traits (eg, waist circumference [r = 0.96]). In mendelian randomization, the associations of genetically elevated BMI with specific proteins were directionally consistent with the observational associations. In meta-analyses of genetically elevated BMI with 8 proteins, combining present estimates with previous studies, the most robust associations were shown for interleukin-6 (per 1-SD higher BMI; 0.21 [95% CI, 0.13-0.29] SD), interleukin-18 (0.16 [95% CI, 0.06-0.26] SD), monocyte chemoattractant protein-1 (0.21 [95% CI, 0.11-0.30] SD), monocyte chemotactic protein-3 (0.12 [95% CI, 0.03-0.21] SD), TNF-related apoptosis-inducing ligand (0.23 [95% CI, 0.13-0.32] SD), and hepatocyte growth factor (0.14 [95% CI, 0.06-0.22] SD). Of the 30 BMI-associated biomarkers, 10 (including interleukin-6, interleukin-18, and hepatocyte growth factor) were nominally associated with incident CVD. Conclusions and Relevance: Mendelian randomization shows adiposity to be associated with a range of protein biomarkers, with some biomarkers also showing association with CVD risk. Future studies are warranted to validate these findings and assess whether proteins may be mediators between adiposity and CVD.

Increased Stromal Infiltrating Lymphocytes Are Associated with the Risk of Disease Progression in Mesenchymal Circulating Tumor Cell-Positive Primary Breast Cancer Patients.

Circulating tumor cells (CTCs) and the immune infiltration of tumors are closely related to clinical outcomes. This study aimed to verify the influence of stromal lymphocyte infiltration and the immune context of tumor microenvironment on the hematogenous spread and prognosis of 282 chemotherapy naïve primary BC patients. To detect the presence of mesenchymal CTCs, RNA extracted from CD45-depleted peripheral blood was interrogated for the expression of mesenchymal gene transcripts. Tumor-infiltrating lymphocytes (TILs) were detected in the stromal areas by immunohistochemistry, using CD3, CD8, and CD45RO antibodies. The concentrations of 51 plasma cytokines were measured by multiplex bead arrays. TILs infiltration in mesenchymal CTC-positive patients significantly decreased their progression-free survival (HR = 4.88, 95% CI 2.30-10.37, p < 0.001 for CD3high; HR = 6.17, 95% CI 2.75-13.80, p < 0.001 for CD8high; HR = 6.93, 95% CI 2.86-16.81, p < 0.001 for CD45ROhigh). Moreover, the combination of elevated plasma concentrations of transforming growth factor beta-3 (cut-off 662 pg/mL), decreased monocyte chemotactic protein-3 (cut-off 52.5 pg/mL) and interleukin-15 (cut-off 17.1 pg/mL) significantly increased the risk of disease recurrence (HR = 4.838, 95% CI 2.048-11.427, p < 0.001). Our results suggest a strong impact of the immune tumor microenvironment on BC progression, especially through influencing the dissemination and survival of more aggressive, mesenchymal CTC subtypes.

Plasma IP-10 and MCP-3 levels are highly associated with disease severity and predict the progression of COVID-19.

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 was first reported in Wuhan, December 2019, and continuously poses a serious threat to public health, highlighting the urgent need of identifying biomarkers for disease severity and progression. OBJECTIVE: We sought to identify biomarkers for disease severity and progression of COVID-19. METHODS: Forty-eight cytokines in the plasma samples from 50 COVID-19 cases including 11 critically ill, 25 severe, and 14 moderate patients were measured and analyzed in combination with clinical data. RESULTS: Levels of 14 cytokines were found to be significantly elevated in COVID-19 cases and showed different expression profiles in patients with different disease severity. Moreover, expression levels of IFN-γ-induced protein 10, monocyte chemotactic protein-3, hepatocyte growth factor, monokine-induced gamma IFN, and macrophage inflammatory protein 1 alpha, which were shown to be highly associated with disease severity during disease progression, were remarkably higher in critically ill patients, followed by severe and then the moderate patients. Serial detection of the 5 cytokines in 16 cases showed that continuously high levels were associated with deteriorated progression of disease and fatal outcome. Furthermore, IFN-γ-induced protein 10 and monocyte chemotactic protein-3 were excellent predictors for the progression of COVID-19, and the combination of the 2 cytokines showed the biggest area under the curve of the receiver-operating characteristics calculations with a value of 0.99. CONCLUSIONS: In this study, we report biomarkers that are highly associated with disease severity and progression of COVID-19. These findings add to our understanding of the immunopathologic mechanisms of severe acute respiratory syndrome coronavirus 2 infection, and provide potential therapeutic targets and strategies.

Differential responses of endothelial integrity upon the intake of microencapsulated garlic, tomato extract or a mixture: a single-intake, randomized, double-blind, placebo-controlled crossover trial.

This study investigated the effect of microencapsulated garlic and/or tomato on endothelial dysfunction induced by the PhenFlex test (PFT) in healthy male smokers. In a randomized, double-blind, placebo-controlled crossover trial, 41 healthy male smokers were randomly assigned to one of four groups to receive the test groups (in microencapsulated garlic powder, tomato extract and a mixture thereof) or the placebo group. Proteomic biomarkers related to endothelial integrity were measured in plasma. Microencapsulated garlic, tomato extract and the mixture affected endothelial integrity biomarkers differently. Garlic consumption increased prothrombin time and decreased SAA and IL-12. Tomato extract intake increased activated partial thrombin time and decreased d-dimer, SAA, sVCAM-1, IL-13 and MCP-3 levels. Consumption of the mixture increased sE-selectin and lowered D-dimer, SAA, IL-13 and IL-10 responses after PFT challenge for 6 h. The different responses became clearer under high compliance in the dietary restriction groups. This single-intake clinical trial addressed the different responses of biomarkers related to endothelial integrity.

Pre-diagnostic blood immune markers, incidence and progression of B-cell lymphoma and multiple myeloma: Univariate and functionally informed multivariate analyses.

Recent prospective studies have shown that dysregulation of the immune system may precede the development of B-cell lymphomas (BCL) in immunocompetent individuals. However, to date, the studies were restricted to a few immune markers, which were considered separately. Using a nested case-control study within two European prospective cohorts, we measured plasma levels of 28 immune markers in samples collected a median of 6 years before diagnosis (range 2.01-15.97) in 268 incident cases of BCL (including multiple myeloma [MM]) and matched controls. Linear mixed models and partial least square analyses were used to analyze the association between levels of immune marker and the incidence of BCL and its main histological subtypes and to investigate potential biomarkers predictive of the time to diagnosis. Linear mixed model analyses identified associations linking lower levels of fibroblast growth factor-2 (FGF-2 p = 7.2 × 10-4 ) and transforming growth factor alpha (TGF-α, p = 6.5 × 10-5 ) and BCL incidence. Analyses stratified by histological subtypes identified inverse associations for MM subtype including FGF-2 (p = 7.8 × 10-7 ), TGF-α (p = 4.08 × 10-5 ), fractalkine (p = 1.12 × 10-3 ), monocyte chemotactic protein-3 (p = 1.36 × 10-4 ), macrophage inflammatory protein 1-alpha (p = 4.6 × 10-4 ) and vascular endothelial growth factor (p = 4.23 × 10-5 ). Our results also provided marginal support for already reported associations between chemokines and diffuse large BCL (DLBCL) and cytokines and chronic lymphocytic leukemia (CLL). Case-only analyses showed that Granulocyte-macrophage colony stimulating factor levels were consistently higher closer to diagnosis, which provides further evidence of its role in tumor progression. In conclusion, our study suggests a role of growth-factors in the incidence of MM and of chemokine and cytokine regulation in DLBCL and CLL.

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.

Altered activation of innate immunity associates with white matter volume and diffusion in first-episode psychosis.

First-episode psychosis (FEP) is associated with inflammatory and brain structural changes, but few studies have investigated whether systemic inflammation associates with brain structural changes in FEP. Thirty-seven FEP patients (median 27 days on antipsychotic medication), and 19 matched controls were recruited. Serum levels of 38 chemokines and cytokines, and cardiovascular risk markers were measured at baseline and 2 months later. We collected T1- and diffusion-weighted MRIs with a 3 T scanner from the patients at baseline. We analyzed the association of psychosis-related inflammatory markers with gray and white matter (WM) volume using voxel-based morphometry and WM diffusion using tract-based spatial statistics with whole-brain and region-of-interest (ROI) analyses. FEP patients had higher CCL22 and lower TGFα, CXCL1, CCL7, IFN-α2 and ApoA-I than controls. CCL22 decreased significantly between baseline and 2 months in patients but was still higher than in controls. The association between inflammatory markers and FEP remained significant after adjusting for age, sex, smoking and BMI. We did not observe a correlation of inflammatory markers with any symptoms or duration of antipsychotic treatment. Baseline CCL22 levels correlated negatively with WM volume and positively with mean diffusivity and radial diffusivity bilaterally in the frontal lobes in ROI analyses. Decreased serum level of ApoA-I was associated with smaller volume of the medial temporal WM. In whole-brain analyses, CCL22 correlated positively with mean diffusivity and radial diffusivity, and CXCL1 associated negatively with fractional anisotropy and positively with mean diffusivity and radial diffusivity in several brain regions. This is the first report to demonstrate an association between circulating chemokine levels and WM in FEP patients. Interestingly, CCL22 has been previously implicated in autoimmune diseases associated with WM pathology. The results suggest that an altered activation of innate immunity may contribute to WM damage in psychotic disorders.

Counteract of bone marrow of blotchy mice against the increases of plasma copper levels induced by high-fat diets in LDLR-/- mice.

BACKGROUND: Bone marrow of blotchy mouse (blotchy marrow) reflects the function of transmembrane domain and relevant intramembrane sites of ATP7A in myeloid cells. By chronic infusion of angiotensin II, we previously found that blotchy marrow plays a minor role in regulating plasma copper. Moreover, the recipients of blotchy marrow presented a moderate reduction of plasma lipids and inflammatory mediator production. Little is known about whether these changes are a specific response to angiotensin II or reveal a more general role of ATP7A. OBJECTIVE AND DESIGN: We investigated if blotchy marrow reduces plasma lipids and inflammatory mediators induced by high-fat diets. To test this hypothesis, blotchy and control marrows were reconstituted to the recipient mice (irradiated male LDLR-/- mice), followed by high-fat-diet feeding for 4 months. At the end points, plasma metals (copper, zinc and iron), lipid profiling (cholesterol, triglyceride, phospholipids and lipoprotein) and six inflammatory mediators (lymphotacin, MCP3, MCP5, TIMP1, VEGF-A and IP-10) were measured. Parallel experiments were performed using male LDLR-/- mice fed either high-fat diets or chow diets for 4 months. RESULTS: In addition to hyperlipidemia and low-grade inflammation, high-fat diets selectively increased plasma copper concentration compared to chow diets in LDLR-/- mice. After high-fat-diet feeding, the recipients with blotchy marrow showed a decrease in plasma copper (p < 0.01) and an increase in plasma iron (p < 0.05). The recipients with blotchy marrow also presented decreases in cholesterol (p < 0.01) and phospholipids (p < 0.05) in plasma. Surprisingly, plasma levels of MCP3 (p < 0.05), MCP5 (p < 0.05), TIMP1 (p < 0.01), VEGF-A (p < 0.01) and IP-10 (p < 0.01) were significantly increased in the recipients with blotchy marrow compared to controls; the increased levels of MCP3, MCP5 and TIMP1 were more than 50%. CONCLUSION: Our studies showed that blotchy marrow counteracts the increased copper levels induced by high-fat diets, indicating that circulating myeloid cells can regulate blood copper levels via ATP7A. Moreover, transplantation of blotchy marrow followed by high-fat diets leads to a decrease in lipid profile and an increase in inflammatory mediator production. Overall, blotchy marrow mediates divergent responses to angiotensin II and high-fat diets in vivo.

Up-regulation of the monocyte chemotactic protein-3 in sera from bone marrow transplanted children with torquetenovirus infection.

BACKGROUND: Torquetenovirus (TTV) represents a commensal human virus producing life-long viremia in approximately 80% of healthy individuals of all ages. A potential pathogenic role for TTV has been suggested in immunocompromised patients with hepatitis of unknown etiology sustained by strong proinflammatory cytokines. OBJECTIVES: The aim of this study was to investigate the sera immunological profile linked to TTV infection in bone marrow transplant (BMT) children with liver injury. STUDY DESIGN: TTV infection was assessed in sera from 27 BMT patients with altered hepatic parameters and histological features, by the use of quantitative real-time PCR, along with TTV genogroups and coinfection with HEV. The qualitative and quantitative nature of soluble inflammatory factors was evaluated studying a large set of cytokines using the Bioplex platform. As controls, sera from 22 healthy children negative for serological and molecular hepatitis markers including TTV and HEV, and for autoimmune diseases, were selected. RESULTS AND CONCLUSIONS: TTV was detected in 81.4% of BMT patients with a viral load ranging from 10(5) to 10(9) copies/mL. All samples were HEV-RNA negative. A pattern of cytokines, IFN-γ, TNF-α, FGF-basic (p<0.01) and MCP-3 (p<0.001) was found significantly highly expressed in TTV-positive patients compared to TTV-negative and controls. Of note, MCP-3 chemokine showed the highest sera concentration independently of the amount of TTV load and the status of immune system deregulation (p<0.001). In this pilot study for the first time, a positive association was found between TTV and increased level of MCP-3 suggesting a indirect role of TTV in liver injury.

A bioplex analysis of cytokines and chemokines in first trimester maternal plasma to screen for predictors of miscarriage.

BACKGROUND: We have previously shown in two independent cohorts that circulating first trimester Macrophage Inhibitory Cytokine-1 (MIC-1) levels are lower in women in early pregnancy who are destined to miscarriage. While promising, the diagnostic performance of measuring MIC-1 alone was not sufficient for it to be a useful predictive test for miscarriage. Besides MIC-1, there are other cytokines, as well as chemokines, involved in facilitating early pregnancy. We reasoned that screening these factors in maternal plasma could uncover other predictive markers of miscarriage. METHODS: This was a nested case control study, of 78 women from a prospective study of 462 attending the Early Pregnancy Assessment Unit in the first trimester (EPAU) with a threatened miscarriage; 34 of these subsequently miscarried (cases) and 44 went on to have a normal delivery (controls) Cytokines IL-1ß, IL-6 and IL-10, and the chemokines, CXCL8, CCL2, CCL5, CCL7 and CX3CL1 were measured in plasma from our cohort. RESULTS: The cytokines IL-1ß, IL-6, IL-10 and the chemokine CXCL8 were not detectable in first trimester plasma. The chemokines CCL2, CCL5, CCL7 and CX3CL1 were detectable in all samples but levels did not vary across 5-12 weeks of gestation among controls. Plasma levels of these chemokines were no different in the miscarriage cohort compared to controls. CONCLUSION: The chemokines CCL2, CCL5, CCL7 and CX3CL1 were detectable in plasma during the first trimester while IL-1ß, IL-6, IL-10 and CXCL8 were not. However, none of the cytokines and chemokines screened were different in maternal plasma in cases or controls. These therefore do not appear to have potential for application as predictive biomarkers of miscarriage.

Stem cell homing factor, CCL7, expression in mouse models of stress urinary incontinence.

OBJECTIVES: Animal models of vaginal distention (VD) have demonstrated increased expression of chemokine (C-C motif) ligand 7 (CCL7) In this study, we investigated the expression of CCL7 in mice models of simulated birth trauma-induced urinary incontinence using VD and pudendal nerve transection (PNT). METHODS: Forty-nine mice were divided into 6 groups: VD, sham VD, PNT, sham PNT, anesthesia, and age-matched controls. The urethra, vagina, and rectum were harvested for the expression of CCL7 immediately or 24 hours after assigned procedure. Venous sampling for quantification of serum CCL7 was also performed. An analysis of variance model was used to compare the relative expression of CCL7 in each group. RESULTS: Urethral CCL7 expression in the VD group was significantly higher than control group after 24 hours (P < 0.01). There was no difference in the urethral CCL7 expression in PNT, sham PNT, sham VD, or anesthesia groups compared with the controls. No statistically significant difference was noted in the vaginal and rectal expression of CCL7 between any of the groups except for sham PNT. Statistically significant differences were noted in the serum CCL7 expression in the VD, PNT, and sham PNT (P < 0.01 in all) groups after 24 hours compared with the control group. CONCLUSIONS: This study demonstrates overexpression of urethral CCL7 after VD but not PNT. This suggests that nerve injury does not contribute to the CCL7 overexpression. The overexpression of CCL7 in the serum of mice after VD suggests a translational potential where CCL7 measurement could be used as a surrogate for injury after delivery.

B lymphocytes trigger monocyte mobilization and impair heart function after acute myocardial infarction.

Acute myocardial infarction is a severe ischemic disease responsible for heart failure and sudden death. Here, we show that after acute myocardial infarction in mice, mature B lymphocytes selectively produce Ccl7 and induce Ly6C(hi) monocyte mobilization and recruitment to the heart, leading to enhanced tissue injury and deterioration of myocardial function. Genetic (Baff receptor deficiency) or antibody-mediated (CD20- or Baff-specific antibody) depletion of mature B lymphocytes impeded Ccl7 production and monocyte mobilization, limited myocardial injury and improved heart function. These effects were recapitulated in mice with B cell-selective Ccl7 deficiency. We also show that high circulating concentrations of CCL7 and BAFF in patients with acute myocardial infarction predict increased risk of death or recurrent myocardial infarction. This work identifies a crucial interaction between mature B lymphocytes and monocytes after acute myocardial ischemia and identifies new therapeutic targets for acute myocardial infarction.

Signaling lymphocyte activation molecule regulates development of colitis in mice.

BACKGROUND & AIMS: Signaling lymphocyte activation molecule (Slamf)1 is a co-stimulatory receptor on T cells and regulates cytokine production by macrophages and dendritic cells. Slamf1 regulates microbicidal mechanisms in macrophages, therefore we investigated whether the receptor affects development of colitis in mice. METHODS: We transferred CD45RB(hi) CD4(+) T cells into Rag(-/-) or Slamf1(-/-)Rag(-/-) mice to induce colitis. We also induced colitis by injecting mice with an antibody that activates CD40. We determined the severity of enterocolitis based on disease activity index, histology scores, and levels of cytokine production, and assessed the effects of antibodies against Slamf1 on colitis induction. We quantified migration of monocytes and macrophage to inflamed tissues upon induction of colitis or thioglycollate-induced peritonitis and in response to tumor necrosis factor-α in an air-pouch model of leukocyte migration. RESULTS: Colitis was reduced in Slamf1(-/-)Rag(-/-) mice, compared with Rag(-/-) mice, after transfer of CD45RB(hi) CD4(+) T cells or administration of the CD40 agonist. The numbers of monocytes and macrophages were reduced in inflamed tissues of Slamf1(-/-)Rag(-/-) mice, compared with Rag(-/-) mice, after induction of colitis and other inflammatory disorders. An antibody that inhibited Slamf1 reduced the level of enterocolitis in Rag(-/-) mice. CONCLUSIONS: Slamf1 contributes to the development of colitis in mice. It appears to indirectly regulate the appearance of monocytes and macrophages in inflamed intestinal tissues. Antibodies that inhibit Slamf1 reduce colitis in mice, so human SLAMF1 might be a therapeutic target for inflammatory bowel disease.

Inhalation exposure of gas-metal arc stainless steel welding fume increased atherosclerotic lesions in apolipoprotein E knockout mice.

Epidemiological studies suggest that welding, a process which generates an aerosol of inhalable gases and metal rich particulates, increases the risk for cardiovascular disease. In this study we analyzed systemic inflammation and atherosclerotic lesions following gas metal arc-stainless steel (GMA-SS) welding fume exposure. Apolipoprotein E knockout (apoE(-/-)) mice, fed a Western diet, were exposed to GMA-SS at 40mg/m(3) for 3h/day for ten days (∼8.26µg daily alveolar deposition). Mice were sacrificed two weeks after exposure and serum chemistry, serum protein profiling and aortic lesion area were determined. There were no significant changes in serum total cholesterol, triglycerides or alanine aminotransferase. Serum levels of uric acid, a potent antioxidant, were decreased perhaps suggesting a reduced capacity to combat systemic oxidative stress. Inflammatory serum proteins interleukin 1 beta (IL-1ß) and monocyte chemoattractant protein 3 (MCP-3) were increased two weeks after GMA-SS exposure. Analysis of atherosclerotic plaques showed an increase in lesion area as the result of GMA-SS exposure. In conclusion, GMA-SS exposure showed evidence of systemic inflammation and increased plaque progression in apoE(-/-) mice. These results complement epidemiological and functional human studies that suggest welding may result in adverse cardiovascular effects.

Evidence for endotoxin contamination in plastic Na+-heparin blood collection tube lots.

BACKGROUND: Biomarker assays are often conducted on whole blood samples in the course of drug development studies. Because bacterial lipopolysaccharide (LPS) (endotoxin) contamination is known to cause spontaneous cytokine production by monocytes, contamination of blood collection tubes may interfere with biomarker assay results. METHODS: Whole blood from healthy donors was collected into plastic or glass sodium (Na(+))-heparin Vacutainer() blood collection tubes and heparinized syringes. Samples were analyzed for phosphoprotein response, cytokine production, and RNA expression. Tubes were tested for endotoxin contamination by use of the limulus amoebocyte lysate assay. RESULTS: Results of phospho-flow cytometry, branched DNA (bDNA), and ELISA assays indicated that a specific lot (#5339582) of plastic Na(+)-heparin Vacutainer tubes was highly contaminated with an endotoxinlike substance, and contamination was confirmed by the limulus amoebocyte lysate assay. Analysis of multiple-analyte panels revealed that analytes whose changed expression was predictive of LPS stimulation were increased when whole blood was incubated in contaminated tubes for 6 or 18 h. Two additional lots of plastic tubes tested had detectable amounts of endotoxin sufficient to strongly alter phospho-flow cytometry analyses, as determined by the fold change in phosphorylation of p38 mitogen-activated protein kinase in response to tumor necrosis factor alpha and LPS. In contrast, 3 lots of glass tubes had substantially lower levels of spontaneous blood activation. CONCLUSIONS: Endotoxin contamination associated with tubes from 3 lots of a particular type of plastic Na(+)-heparin Vacutainer tube dramatically affected biomarker assay measurements. Prescreening these tubes is suggested before their use in clinical sample analysis.