Elevated expression of TARC (CCL17) and MDC (CCL22) in models of cigarette smoke-induced pulmonary inflammation

CCL22 Induces the Polarization of Immature Dendritic Cells into Tolerogenic Dendritic Cells in Radiation-Induced Lung Injury through the CCR4-Dectin2-PLC-γ2-NFATC2-Nr4a2-PD-L1 Signaling Pathway

Recruitment of immune cells to the injury site plays a pivotal role in the pathology of radiation-associated diseases. In this study, we investigated the impact of the chemokine CCL22 released from alveolar type II epithelial (AT2) cells after irradiation on the recruitment and functional changes of dendritic cells (DCs) in the development of radiation-induced lung injury (RILI). By examining changes in CCL22 protein levels in lung tissue of C57BL/6N mice with RILI, we discovered that ionizing radiation increased CCL22 expression in irradiated alveolar AT2 cells, as did MLE-12 cells after irradiation. A transwell migration assay revealed that CCL22 promoted the migration of CCR4-positive DCs to the injury site, which explained the migration of pulmonary CCR4-positive DCs in RILI mice in vivo. Coculture experiments demonstrated that, consistent with the response of regulatory T cells in the lung tissue of RILI mice, exogenous CCL22-induced DCs promoted regulatory T cell proliferation. Mechanistically, we demonstrated that Dectin2 and Nr4a2 are key targets in the CCL22 signaling pathway, which was confirmed in pulmonary DCs of RILI mice. As a result, CCL22 upregulated the expression of PD-L1, IL-6, and IL-10 in DCs. Consequently, we identified a mechanism in which CCL22 induced DC tolerance through the CCR4-Dectin2-PLC-γ2-NFATC2-Nr4a2-PD-L1 pathway. Collectively, these findings demonstrated that ionizing radiation stimulates the expression of CCL22 in AT2 cells to recruit DCs to the injury site and further polarizes them into a tolerant subgroup of CCL22 DCs to regulate lung immunity, ultimately providing potential therapeutic targets for DC-mediated RILI.

Bronchoalveolar cytokine profile differentiates Pulmonary Langerhans cell histiocytosis patients from other smoking-related interstitial lung diseases

BACKGROUND

Pulmonary Langerhans cell histiocytosis (PLCH) is a rare interstitial lung disease (ILD) associated with smoking, whose definitive diagnosis requires the exclusion of other forms of ILD and a compatible surgical lung biopsy. Bronchoalveolar lavage (BAL) is commonly proposed for the diagnosis of ILD, including PLCH, but the diagnostic value of this technique is limited. Here, we have analyzed the levels of a panel of cytokines and chemokines in BAL from PLCH patients, in order to identify a distinct immune profile to discriminate PLCH from other smoking related-ILD (SR-ILD), and comparing the results with idiopathic pulmonary fibrosis (IPF) as another disease in which smoking is considered a risk factor.

METHODS

BAL samples were collected from thirty-six patients with different ILD, including seven patients with PLCH, sixteen with SR-ILD and thirteen with IPF. Inflammatory profiles were analyzed using the Human Cytokine Membrane Antibody Array. Principal component analysis (PCA) was performed to reduce dimensionality and protein-protein interaction (PPI) network analysis using STRING 11.5 database were conducted. Finally, Random forest (RF) method was used to build a prediction model.

RESULTS

We have found significant differences (p < 0.05) on thirty-two cytokines/chemokines when comparing BAL from PLCH patients with at least one of the other ILD. Four main groups of similarly regulated cytokines were established, identifying distinct sets of markers for each cluster. Exploratory analysis using PCA (principal component analysis) showed clustering and separation of patients, with the two first components capturing 69.69% of the total variance. Levels of TARC/CCL17, leptin, oncostatin M (OSM) and IP-10/CXCL10 were associated with lung function parameters, showing positive correlation with FVC. Finally, random forest (RF) algorithm demonstrates that PLCH patients can be differentiated from the other ILDs based solely on inflammatory profile (accuracy 96.25%).

CONCLUSIONS

Our results show that patients with PLCH exhibit a distinct BAL immune profile to SR-ILD and IPF. PCA analysis and RF model identify a specific immune profile useful for discriminating PLCH.

Modulation of low-dose ozone and LPS exposed acute mouse lung inflammation by IF1 mediated ATP hydrolysis inhibitor, BTB06584

Ozone and bacterial lipopolysaccharide (LPS) are common air pollutants that are related to high hospital admissions due to airway hyperreactivity and increased susceptibility to infections, especially in children, older population and individuals with underlying conditions. We modeled acute lung inflammation (ALI) by exposing 6-8 week old male mice to 0.005 ppm ozone for 2 h followed by 50 μg of intranasal LPS. We compared the immunomodulatory effects of single dose pre-treatment with CD61 blocking antibody (clone 2C9.G2), ATPase inhibitor BTB06584 against propranolol as the immune-stimulant and dexamethasone as the immune-suppressant in the ALI model. Ozone and LPS exposure induced lung neutrophil and eosinophil recruitment as measured by respective peroxidase (MPO and EPX) assays, systemic leukopenia, increased levels of lung vascular neutrophil regulatory chemokines such as CXCL5, SDF-1, CXCL13 and a decrease in immune-regulatory chemokines such as BAL IL-10 and CCL27. While CD61 blocking antibody and BTB06584 produced maximum increase in BAL leukocyte counts, protein content and BAL chemokines, these treatments induced moderate increase in lung MPO and EPX content. CD61 blocking antibody induced maximal BAL cell death, a markedly punctate distribution of NK1.1, CX3CR1, CD61. BTB06584 preserved BAL cell viability with cytosolic and membrane distribution of Gr1 and CX3CR1. Propranolol attenuated BAL protein, protected against BAL cell death, induced polarized distribution of NK1.1, CX3CR1 and CD61 but presented with high lung EPX. Dexamethasone induced sparse cell membrane distribution of CX3CR1 and CD61 on BAL cells and displayed very low lung MPO and EPX levels despite highest levels of BAL chemokines. Our study unravels ATPase inhibitor IF1 as a novel drug target for lung injury.

Effects of Smoking on Inflammatory-Related Cytokine Levels in Human Serum

Cardiovascular and respiratory diseases, and several cancers resulting from tobacco smoking, are initially characterized by chronic systemic inflammation. Cytokine imbalances can result in inflammation, making it important to understand the pathological mechanisms behind cytokine production. In this study, we collected blood samples from 78 healthy male volunteers, including non-smokers (n = 30), current smokers (n = 30), and ex-smokers (n = 18), and utilized the liquid suspension chip technique to investigate and compare the expression levels of 17 cytokines and chemokines in the human serum of these volunteers. The results demonstrated that the expression levels of CXCL9/MIG and sIL-6R significantly increased after smoking, and continued to increase after quitting smoking. The expression levels of TARC, ITAC, and sVEGFR-3 increased after smoking but decreased after quitting smoking; the expression level of SAA significantly decreased after smoking and showed an upward trend after quitting smoking. Seven cytokines (IL-1β, BCA-1, TNF-α, CRP, ENA-78, MDC, and TNFRII) did not vary between the three groups, while four cytokines (IL-1α, IL-6, IL-8, and SCF) were not detected in any serum sample. In conclusion, this study assessed the physiological production of cytokines and chemokines, highlighting the differences in each due to smoking status. Our results could help evaluate the early development of smoking-related chronic diseases and cancers.

Artemisia gmelinii Attenuates Lung Inflammation by Suppressing the NF-κB/MAPK Pathway

Cigarette smoke (CS) is the main cause of chronic obstructive pulmonary disease (COPD), and continuous CS exposure causes lung inflammation and deterioration. To investigate the protective effects of Artemisia gmelinii against lung inflammation in this study, cigarette smoke extract (CSE)/lipopolysaccharide (LPS)-treated alveolar macrophages (AMs) and mice stimulated with CSE/porcine pancreas elastase (PPE) were used. Artemisia gmelinii ethanol extract (AGE) was effective in decreasing the levels of cytokines, chemokine, inducible nitric oxide synthase, and cyclooxygenase-2 by inhibiting mitogen-activated protein (MAP) kinases/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway in AMs. Additionally, oral administration of AGE suppressed inflammatory cells’ infiltration and secretion of inflammatory cytokines, chemokines, matrix metallopeptidase 9, and neutrophil extracellular traps in bronchoalveolar lavage fluid from the COPD model. Moreover, the obstruction of small airways, the destruction of the lung parenchyma, and expression of IL-6, TNF-α, IL-1β, and MIP-2 were suppressed by inhibiting NF-κB activation in the lung tissues of the AGE group. These effects are associated with scopolin, chlorogenic acid, hyperoside, 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid, which are the main components of AGE. These data demonstrate the mitigation effect of AGE on lung inflammation via inhibition of MAPK and NF-κB pathways, suggesting that AGE may be instrumental in improving respiratory and lung health.

Role of CC Chemokine Ligand 17 in Mouse Models of Chronic Obstructive Pulmonary Disease

Lung function deterioration is significantly associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). We previously reported that CC chemokine ligand 17/thymus and activation-regulated chemokine (CCL17/TARC) could be a predictive factor of lung function decline in patients with COPD. However, the role of CCL17 in the pathogenesis of COPD is unclear. Here we examined the role of CCL17 in lung inflammation using mouse COPD models. Exposure to cigarette smoking induced CCL17 production in bronchial epithelial cells and accumulation of alveolar macrophages in the lungs. Intranasal administration of recombinant CCL17 further enhanced cigarette smoke-induced macrophage accumulation and also aggravated elastase-induced pulmonary emphysema. We confirmed that cigarette smoke extract as well as H₂O₂ upregulated CCL17 in BAES-2B cells. Of note, macrophages of both M1 and M2 surface markers were accumulated by cigarette smoke. Both alveolar macrophage accumulation via exposure to cigarette smoking and emphysematous changes induced by elastase administration were significantly reduced in CCL17-deficient mice. We further demonstrated that CCL17 strongly induced the expression of CC chemokine ligand 2 (CCL2), a chemoattractant for macrophages, in RAW264.7 cells, and its production was inhibited by knockdown of CCR4, the receptor of CCL17. Collectively, the present results demonstrate that CCL17 is produced by lung epithelial cells upon cigarette smoke (CS) exposure. Furthermore, CCL17 is involved in CS-induced accumulation of alveolar macrophages and development of elastase-induced pulmonary emphysema, possibly through CCL17-induced production of CCL2 by macrophages. Our findings may provide a new insight into the pathogenesis of COPD.

Response biomarkers of inhalation exposure to cigarette smoke in the mouse lung

Cigarette smoking is known to increase the risk of cancer and chronic obstructive pulmonary disease (COPD). In this study, we evaluated the effects of short-term nose-only inhalation exposure to cigarette smoke in mice. Male 10-week-old C57BL mice were exposed to clean air (control) or mainstream cigarette smoke for 1 h/day, 5 days/week, for 2 or 4 weeks. Exposure to cigarette smoke increased the number of inflammatory cells, especially neutrophils, in the bronchoalveolar lavage fluid, increased inflammatory cell infiltration foci, and caused an increase in the thickness of the peripheral bronchial epithelium. Microarray gene expression analysis indicated that smoke exposure induced inflammatory responses, including leukocyte migration and activation of phagocytes and myeloid cells, as early as two weeks after the initiation of exposure. Importantly, chemokine (C-C motif) ligand 17, resistin-like alpha, and lipocalin 2 were upregulated and may serve as useful markers of the toxic effects of exposure to cigarette smoke before pulmonary histological changes become evident.

Lymphoma-Associated Biomarkers Are Increased in Current Smokers in Twin Pairs Discordant for Smoking

Simple Summary

Smoking is associated with a moderate increased risk of Hodgkin and follicular lymphoma. To help understand why, we examined lymphoma-related biomarker levels among 134 smoking and non-smoking twins (67 pairs) ascertained from the Finnish Twin Cohort. We validated self-reported smoking history by measuring serum cotinine, a metabolite of nicotine, from previously collected frozen serum samples. In total, 27 immune biomarkers were assayed using the Luminex Multiplex platform (R & D Systems). We found that four immune response biomarkers were higher and one was lower among smoking compared to non-smoking twins. The strongest association was observed for CCL17/TARC, a biomarker elevated in Hodgkin lymphoma patients. Immune biomarker levels were similar in former smokers and non-smokers. Current smoking may increase levels of immune proteins that could partially explain the association between smoking and risk of certain lymphomas.

Abstract

Smoking is associated with a moderate increased risk of Hodgkin and follicular lymphoma. To understand why, we examined lymphoma-related biomarker levels among 134 smoking and non-smoking twins (67 pairs) ascertained from the Finnish Twin Cohort. Previously collected frozen serum samples were tested for cotinine to validate self-reported smoking history. In total, 27 immune biomarkers were assayed using the Luminex Multiplex platform (R & D Systems). Current and non-current smokers were defined by a serum cotinine concentration of >3.08 ng/mL and ≤3.08 ng/mL, respectively. Associations between biomarkers and smoking were assessed using linear mixed models to estimate beta coefficients and standard errors, adjusting for age, sex and twin pair as a random effect. There were 55 never smokers, 43 current smokers and 36 former smokers. CCL17/TARC, sgp130, haptoglobin, B-cell activating factor (BAFF) and monocyte chemoattractant protein-1 (MCP1) were significantly (p < 0.05) associated with current smoking and correlated with increasing cotinine concentrations (P_trend < 0.05). The strongest association was observed for CCL17/TARC (P_trend = 0.0001). Immune biomarker levels were similar in former and never smokers. Current smoking is associated with increased levels of lymphoma-associated biomarkers, suggesting a possible mechanism for the link between smoking and risk of these two B-cell lymphomas.

Clinical and molecular parameters associated to pneumonitis development in non-small-cell lung cancer patients receiving chemoimmunotherapy from NADIM trial

BACKGROUND

Pneumonitis (Pn) is one of the main immune-related adverse effects, having a special importance in lung cancer, since they share affected tissue. Despite its clinical relevance, Pn development remains an unpredictable treatment adverse effect, whose mechanisms are mainly unknown, being even more obscure when it is associated to chemoimmunotherapy.

METHODS

In order to identify parameters associated to treatment related Pn, we analyzed clinical variables and molecular parameters from 46 patients with potentially resectable stage IIIA non-small-cell lung cancer treated with neoadjuvant chemoimmunotherapy included in the NADIM clinical trial (NCT03081689). Pn was defined as clinical or radiographic evidence of lung inflammation without alternative diagnoses, from treatment initiation to 180 days.

RESULTS

Among 46 patients, 12 developed Pn (26.1%). Sex, age, smoking status, packs-year, histological subtype, clinical or pathological response, progression-free survival, overall survival and number of nivolumab cycles, were not associated to Pn development. Regarding molecular parameters at diagnosis, Pn development was not associated to programmed death ligand 1, TPS, T cell receptor repertoire parameters, or tumor mutational burden. However, patients who developed Pn had statistically significant lower blood median levels of platelet to monocyte ratio (p=0.012) and teratocarcinoma-derived growth factor 1 (p=0.013; area under the curve (AUC) 0.801), but higher median percentages of natural killers (NKs) (p=0.019; AUC 0.786), monocytes (p=0.017; AUC 0.791), MSP (p=0.006; AUC 0.838), PARN (p=0.017; AUC 0.790), and E-Cadherin (p=0.022; AUC 0.788). In addition, the immune scenario of Pn after neoadjuvant treatment involves: high levels of neutrophils and NK cells, but low levels of B and T cells in peripheral blood; increased clonality of intratumoral T cells; and elevated plasma levels of several growth factors (EGF, HGF, VEGF, ANG-1, PDGF, NGF, and NT4) and inflammatory cytokines (MIF, CCL16, neutrophil gelatinase-associated lipocalin, BMP-4, and u-PAR).

CONCLUSIONS

Although statistically underpowered, our results shed light on the possible mechanisms behind Pn development, involving innate and adaptative immunity, and open the possibility to predict patients at high risk. If confirmed, this may allow the personalization of both, the surveillance strategy and the therapeutic approaches to manage Pn in patients receiving chemoimmunotherapy.

Impact of Differentiated Macrophage-Like Cells on the Transcriptional Toxicity Profile of CuO Nanoparticles in Co-Cultured Lung Epithelial Cells

To mimic more realistic lung tissue conditions, co-cultures of epithelial and immune cells are one comparatively easy-to-use option. To reveal the impact of immune cells on the mode of action (MoA) of CuO nanoparticles (NP) on epithelial cells, A549 cells as a model for epithelial cells have been cultured with or without differentiated THP-1 cells, as a model for macrophages. After 24 h of submerged incubation, cytotoxicity and transcriptional toxicity profiles were obtained and compared between the cell culture systems. Dose-dependent cytotoxicity was apparent starting from 8.0 µg/cm² CuO NP. With regard to gene expression profiles, no differences between the cell models were observed concerning metal homeostasis, oxidative stress, and DNA damage, confirming the known MoA of CuO NP, i.e., endocytotic particle uptake, intracellular particle dissolution within lysosomes with subsequent metal ion deliberation, increased oxidative stress, and genotoxicity. However, applying a co-culture of epithelial and macrophage-like cells, CuO NP additionally provoked a pro-inflammatory response involving NLRP3 inflammasome and pro-inflammatory transcription factor activation. This study demonstrates that the application of this easy-to-use advanced in vitro model is able to extend the detection of cellular effects provoked by nanomaterials by an immunological response and emphasizes the use of such models to address a more comprehensive MoA.

Immune Trait Shifts in Association With Tobacco Smoking: A Study in Healthy Women

Tobacco smoking is known to impact circulating levels of major immune cells populations, but its effect on specific immune cell subsets remains poorly understood. Here, using high-resolution data from 223 healthy women (25 current and 198 never smokers), we investigated the association between smoking status and 35,651 immune traits capturing immune cell subset frequencies. Our results confirmed that active tobacco smoking is associated with increased frequencies of circulating CD8+ T cells expressing the CD25 activation marker. Moreover, we identified novel associations between smoking status and relative abundances of CD8+ CD25+ memory T cells, CD8+ memory T cells expressing the CCR4 chemokine receptor, and CD4+CD8+ (double-positive) CD25+ T cells. We also observed, in current smokers, a decrease in the relative frequencies of CD4+ T cells expressing the CD38 activation marker and an increase in class-switched memory B cell isotypes IgA, IgG, and IgE. Finally, using data from 135 former female smokers, we showed that the relative frequencies of immune traits associated with active smoking are usually completely restored after smoking cessation, with the exception of subsets of CD8+ and CD8+ memory T cells, which persist partially altered. Our results are consistent with previous findings and provide further evidence on how tobacco smoking shapes leukocyte cell subsets proportion toward chronic inflammation.

Thymus and activation-regulated chemokine (TARC/CCL17) predicts decline of pulmonary function in patients with chronic obstructive pulmonary disease

BACKGROUND

The deterioration of pulmonary function, such as FEV₁-decline, is strongly associated with poor prognosis in patients with chronic obstructive pulmonary disease (COPD). However, few investigations shed light on useful biomarkers for predicting the decline of pulmonary function. We evaluated whether thymus and activation-regulated chemokine (TARC), a Th2 inflammation marker, could predict rapid FEV₁-decline in COPD patients.

METHODS

We recruited 161 patients with stable COPD and performed pulmonary function test once every six months. At the time of registration, blood tests, including serum levels of TARC were performed. We assessed the correlation between changes in parameters of pulmonary function tests and serum levels of TARC. The rapid-decline in pulmonary function was determined using 25th percentile of change in FEV₁ or FEV₁ percent predicted (%FEV₁) per year.

RESULTS

In the FEV₁-rapid-decline group, the frequency of exacerbations, the degree of emphysema, and serum levels of TARC was higher than in the non-rapid-decline group. When using %FEV₁ as a classifier instead of FEV₁, age, the frequency of exacerbations, the degree of emphysema and serum levels of TARC in the rapid-decline group was significantly greater than those in the non-rapid-decline group. In univariate logistic regression analysis, TARC was the significant predictive factor for rapid-decline group. In multivariate analysis adjusted for emphysema, serum levels of TARC are independently significant predicting factors for the rapid-decline group.

CONCLUSIONS

TARC is an independent predictive biomarker for the rapid-decline in FEV₁. Measuring serum TARC levels may help the management of COPD patients by predicting the risk of FEV₁ decline.

Predictive value of cytokine/chemokine responses for the disease severity and management in children and adult cases with COVID-19

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

Suppression of Inflammatory Cytokines Expression with Bitter Melon (Momordica Charantia) in TNBS-instigated Ulcerative Colitis

Background and Objective

This study was aimed to elucidate the molecular mechanism of Momordica charantia (MCh), along with a standard drug prednisolone, in a rat model of colitis induced by trinitrobenzene sulfonic acid (TNBS).

Methods

After the induction of the experimental colitis, the animals were treated with MCh (4 g/kg/day) for 14 consecutive days by intragastric gavage. The colonic tissue expression levels of C-C motif chemokine ligand 17 (CCL-17), interleukin (IL)-1β, IL-6, IL-23, interferon-γ (IFN-γ), nuclear factor kappa B (NF-kB), and tumor necrosis factor-α (TNF-α), were determined at both mRNA and protein levels to estimate the effect of MCh. Besides, colonic specimens were analyzed histopathologically after staining with hematoxylin and eosin.

Results

The body weights from TNBS-instigated colitis rats were found to be significantly lower than untreated animals. Also, the IFN-γ, IL-1β, IL-6, Il-23, TNF-α, CCL-17, and NF-kB mRNA and protein levels were increased significantly from 1.86-4.91-fold and 1.46-5.50-fold, respectively, in the TNBS-instigated colitis group as compared to the control. Both the MCh and prednisolone treatment significantly reduced the bodyweight loss. It also restored the induced colonic tissue levels of IL-1β, IL-6, IFN-γ, and TNF-α to normal levels seen in untreated animals. These results were also supported with the histochemical staining of the colonic tissues from both control and treated animals.

Conclusion

The presented data strongly suggests that MCh has the anti-inflammatory effect that might be modulated through vitamin D metabolism. It is the right candidate for the treatment of UC as an alternative and complementary therapeutics.

Alteration of immunophenotype of human macrophages and monocytes after exposure to cigarette smoke

Cigarette smoke exposure (CS) is the main risk factor for chronic obstructive pulmonary disease (COPD). Macrophages have an important role in COPD because they release pro-inflammatory and anti-inflammatory cytokines. The present study's we investigate the functional changes in macrophages and monocytes exposed to cigarette smoke extract (CSE). Herein, using human monocyte-derived macrophages (MDMs) from healthy donors and we found that CSE was not associated with significant changes in the production of pro inflammatory cytokines by MDMs. In contrast, exposure to CSE suppressed the production of IL-6 and Gro-a/CXCL1 by LPS-stimulated-MDMs, but had an additive effect on the release of IL-8/CXCL8 and MCP1/CCL2. However, CSE exposure was associated with greater production, TARC/CCL-17 and CCL22/MDC. Moreover, MDMs displayed a lower uptake capacity after CSE exposure. We identify, for what is to our knowledge the first time that monocytes from patients with COPD produced less IL-8/CXCL8 and Gro-α/CXCL1 after LPS stimulation and produced higher levels of TARC/CCL17 and MDC/CCL-22 after IL-4 stimulation. Our present results highlighted a skewed immune response, with an imbalance in M1 vs. M2 cytokine production. In conclusion, exposure to CS has contrasting, multifaceted effects on macrophages and monocytes. Our data may provide a better understanding of the mechanisms underlying COPD.

IFNγ and TNFα mediate CCL22/MDC production in alveolar macrophages after hemorrhage and resuscitation

Acute lung injury is a major complication of hemorrhagic shock and the required resuscitation with large volumes of crystalloid fluids and blood products. We previously identified a role of macrophage-derived chemokine (CCL22/MDC) pulmonary inflammation following hemorrhage and resuscitation. However, further details regarding the induction of CCL22/MDC and its precise role in pulmonary inflammation after trauma remain unknown. In the current study we used in vitro experiments with a murine alveolar macrophage cell line, as well as an in vivo mouse model of hemorrhage and resuscitation, to identify key regulators in CCL22/MDC production. We show that trauma induces expression of IFNγ, which leads to production of CCL22/MDC through a signaling mechanism involving p38 MAPK, NF-κB, JAK, and STAT-1. IFNγ also activates TNFα production by alveolar macrophages, potentiating CCL22/MDC production via an autocrine mechanism. Neutralization of IFNγ or TNFα with specific antibodies reduced histological signs of pulmonary injury after hemorrhage and reduced inflammatory cell infiltration into the lungs.

Regulation of the inflammatory response by vascular grafts modified with Aspirin-Triggered Resolvin D1 promotes blood vessel regeneration

The unabated inflammatory response is often the cause for inhibited vascular regeneration of transplanted small-diameter vascular grafts (diameter <6 mm) in vascular replacement therapies. We proposed that stimulating inflammatory resolution could be an effective approach for treatment of chronic vascular graft inflammation after transplantation. Aspirin-Triggered Resolvin D1 (AT-RvD1) plays critical roles in driving cellular processes toward the resolution of inflammation and suppressing downstream inflammatory signaling pathways. With the aim to facilitate vascular regeneration, we developed a polycaprolactone (PCL) vascular graft loaded with AT-RvD1. The results showed that AT-RvD1 promoted macrophage polarization into M2 macrophages in vitro. Macrophages pretreated with AT-RvD1 conditioned medium promoted endothelial cell tube formation. Furthermore, in vivo implantation was performed by replacing rat abdominal aorta. We observed fast endothelialization and enhanced smooth muscle regeneration in rats that received the AT-RvD1-containing graft implants. The presence of AT-RvD1 induced infiltration of a large number of M2 macrophages and integrin α4-positive (CD49d⁺) neutrophils into the graft wall after implantation. Vascular graft RNA-Seq analysis revealed that AT-RvD1 inhibited leukocyte and neutrophil migration and activation. Results also indicated that macrophage polarization to the M2 phenotype was promoted on day 7 post-implantation. These results demonstrated the ability of locally delivered AT-RvD1 to increase pro-regenerative immune subpopulations and promote vascular tissue regeneration. STATEMENT OF SIGNIFICANCE: Chronic inflammation is a key deciding factor in the failure of vascular regeneration of transplanted small-diameter vascular grafts (diameter <6 mm). Aspirin-triggered Resolvin D1 (AT-RvD1) is a critical driving force in cellular resolution inflammation and suppresses inflammatory signaling. Herein, we developed an electrospun polycaprolactone (PCL) vascular graft loaded with AT-RvD1. In vivo implantation was performed by replacing rat abdominal aorta and AT-RvD1-loaded grafts showed rapid endothelialization, enhanced capillary formation, and excellent smooth muscle regeneration by regulating inflammatory reaction and promoting its rapid resolution. Thus, our study provided new perspectives for long-term vascular graft survival and integration with the host tissue. We believe that AT-RvD1 can be widely applied in tissue engineering owing to its anti-inflammatory and therapeutic effects.

Acanthamoeba profilin elicits allergic airway inflammation in mice

Background

In previous studies, we suggested that Acanthamoeba is a new aero-allergen and that patients who showed positive results for the skin-prick test response to Acanthamoeba cross-reacted with several pollen allergens. Additionally, patients with common antibodies reacted to the 13–15 kDa Acanthamoeba unknown allergen.

Objective

We examined whether profilin of Acanthamoeba is a human airway allergic agent because of its molecular weight.

Methods

We expressed recombinant Ac-PF (rAc-PF) protein using an Escherichia coli expression system and evaluated whether Ac-PF is an airway allergic agent using an allergic airway inflammation animal model.

Results

Airway hyperresponsiveness was increased in rAc-PF-inoculated mice. The number of eosinophils and levels of Th2 cytokines, interleukin (IL)-4, IL-5, and IL-13 were increased in the bronchial alveolar lavage fluid of rAc-PF-treated mice. The lungs of the rAc-PF-treated mice group showed enhanced mucin production and metaplasia of lung epithelial cells and goblet cells.

Conclusion

In this study, we demonstrated that rAc-PF may be an allergen in Acanthamoeba, but further studies needed to identify the mechanisms of allergenic reactions induced by Ac-PF.

Recently, the number of asthma patients have increased sharply. Among patients with asthma have a high serum IgE titer, but despite this, some of these patients do not react to known allergens in skin prick tests, that suggests the presence of unknown environmental allergens. The protozoa Acanthamoeba live in very diverse environment including water, soil, air and even human nasal cavities, throat, pharynx and lung. In previous study, Acanthamoeba could be a new aero-allergen. Patients who showed positive results for the skin-prick test response to Acanthamoeba, their serum could be cross-reacted with several pollen allergens as well as Acanthamoeba total proteins. Additionally, the patients have common antibodies reacted to the 13–15 kDa Acanthamoeba unknown allergen. Profilin, which is found in all eukaryotic organisms in most cells, is an actin-binding protein that interferes with nucleation and restructuring of new filaments. Recent studies showed that profilin functions as a pan-allergen recognized by IgE in approximately 20% of birch pollen and plant food allergic patients. In Acanthamoeba, two isoforms of profilin (Ac-PF) have been identified: profilin-I and profilin-II. We examined profilin from Acanthamoeba as a potential human airway allergic agent because of its molecular weight (13–14 kDa) and cross-reactivity with several pollen allergens in the skin prick test showing positive results for Acanthamoeba in chronic cough patients. In this study, we expressed recombinant Ac-PF (rAc-PF) protein using an Escherichia coli expression system and evaluated whether Ac-PF is an airway allergic agent using an asthma animal model. Our study showed that rAc-PF may be an allergen in Acanthamoeba, but further studies needed to identify the mechanisms of allergenic reactions induced by Ac-PF.

Cigarette Smoking Modulation of Saliva Microbial Composition and Cytokine Levels

Tobacco use has been implicated as an immunomodulator in the oral cavity and contributes to the development of oral cancer. In the present study, we investigated the effects of cigarette smoking on bacterial diversity and host responses compared to healthy nonsmoking controls. Saliva samples were collected from eighteen smokers and sixteen nonsmoking individuals by passive drool. The 16S rRNA gene was used to characterize the salivary microbiome by using the Illumina MiSeq platform. Cytokine and chemokine expression analyses were performed to evaluate the host response. Significant differences in cytokine and chemokine expression levels of MDC, IL-10, IL-5, IL-2, IL-4, IL-7, adrenocorticotropic hormone (ACTH), insulin, and leptin were observed between smokers and nonsmokers. Taxonomic analyses revealed differences between the two groups, and some bacterial genera associated with the smokers group had correlations with hormones and cytokines identified as statistically different between smokers and nonsmokers. These factors have been associated with inflammation and carcinogenesis in the oral cavity. The data obtained may aid in the identification of the interactions between the salivary microbiome, host inflammatory responses, and metabolism in smokers.

Drug-induced interstitial lung disease in the treatment of malignant lymphoma as a potential diagnostic marker: a comparison of serum Krebs von Lungen-6 and thymus and activation-regulated chemokine/CC chemokine ligand 17

Purpose

Cure-oriented treatment of malignant lymphoma (ML) is possible even in an advanced stage; however, the progression of drug-induced interstitial lung disease (DILD) sometimes accounts for poor clinical outcomes. This study aims to assess the incidence and clinical characteristics of DILD among patients with ML and compares the serum level of Krebs von den Lungen-6 (KL-6) with that of circulating thymus and activation-regulated chemokine (TARC)/CC chemokine ligand 17 (CCL17) as a diagnostic biomarker for DILD.

Patients and methods

Between July 2011 and August 2016, we enrolled 36 patients with ML who were undergoing systemic chemotherapy at our hospital. Then, we evaluated the serum concentration of KL-6 and TARC/CCL17 by a sandwich-type electrochemiluminescence immunoassay and enzyme-linked immunosorbent assay, respectively.

Results

DILD developed in 22.2% of patients with ML. All patients recovered immediately after the discontinuation of causative drug and/or glucocorticoid therapy. Although the sensitivity of both TARC/CCL17 and KL-6 was almost equal, the mean concentration of serum KL-6 after the progression of interstitial lung disease was significantly higher than that before progression.

Conclusion

DILD developed in patients who were treated with first-line rituximab combined regimen. Remarkably, TARC/CCL17 and KL-6 seemed approximately equal as a predictive biomarkers for DILD; however, KL-6 was more specific than TARC/CCL17.

Sparse Supervised Classification Methods Predict and Characterize Nanomaterial Exposures: Independent Markers of MWCNT Exposures

Recent experimental evidence indicates significant pulmonary toxicity of multiwalled carbon nanotubes (MWCNTs), such as inflammation, interstitial fibrosis, granuloma formation, and carcinogenicity. Although numerous studies explored the adverse potential of various CNTs, their comparability is often limited. This is due to differences in administered dose, physicochemical characteristics, exposure methods, and end points monitored. Here, we addressed the problem through sparse classification method, a supervised machine learning approach that can reduce the noise contained in redundant variables for discriminating among MWCNT-exposed and MWCNT-unexposed groups. A panel of proteins measured from bronchoalveolar lavage fluid (BAL) samples was used to predict exposure to various MWCNT and determine markers that are attributable to MWCNT exposure and toxicity in mice. Using sparse support vector machine-based classification technique, we identified a small subset of proteins clearly distinguishing each exposure. Macrophage-derived chemokine (MDC/CCL22), in particular, was associated with various MWCNT exposures and was independent of exposure method employed, that is, oropharyngeal aspiration versus inhalation exposure. Sustained expression of some of the selected protein markers identified also suggests their potential role in MWCNT-induced toxicity and proposes hypotheses for future mechanistic studies. Such approaches can be used more broadly for nanomaterial risk profiling studies to evaluate decisions related to dose/time-response relationships that could delineate experimental variables from exposure markers.

The Ratio of Regulatory (FOXP3+) to Total (CD3+) T Cells Determined by Epigenetic Cell Counting and Cardiovascular Disease Risk: A Prospective Case-cohort Study in Non-diabetics

Background

Experimental and clinical evidence indicate that inflammatory processes in atherogenesis and the development of cardiovascular complications are promoted by a loss of regulatory T cell (Treg)-mediated immunological tolerance to plaque antigens. Yet, the association between alterations of systemic Treg frequency and cardiovascular disease incidence remains uncertain.

Methods

A nested case-cohort study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Heidelberg, comprising a random subcohort (n = 778) and primary cases of myocardial infarction (MI, n = 276) and ischemic stroke (n = 151). Pre-diagnostic FOXP3 + Treg and total CD3 + T-lymphocyte (tTL) frequencies in blood were measured by epigenetic-based, quantitative real-time PCR-assisted cell counting.

Results

Multivariate, Prentice-weighted Cox regression analyses revealed that lower Treg/tTL ratios were not associated with the risk of either MI (lowest vs. highest sex-specific quartile; hazard ratio: 0.72, 95% confidence interval: 0.46 to 1.13; P_trend = 0.51) or stroke (HR: 0.90, 95% CI: 0.51 to 1.60; P_trend = 0.78). There were no correlations of Treg/tTL ratios with C-reactive protein, HbA1c, and various lipid parameters.

Conclusions

Among middle-aged adults from the general population, imbalances in the relative frequency of Tregs within the total T cell compartment do not confer an increased risk of MI or stroke.

•

We studied if peripheral immune tolerance, as reflected by regulatory (FOXP3+) to total (CD3+) T cells, relates to CVD risk.

•

Epigenetic-based, qPCR assisted cell counting was used to quantify T cell subsets in long-term stored buffy coat samples.

•

Lower Treg-mediated immune tolerance does not confer an increased risk of major CVD events.

Inflammation in the arterial intima plays a central role in atherosclerotic cardiovascular disease and may develop owing to autoimmune-like responses targeted against plaque antigens. While the ratio between regulatory T cells (Tregs) and effector T cells is thought to control such immune response outcomes and tolerance within the T cell compartment, we found no association with incidence of major CVD events. These findings imply that reduced systemic Treg frequencies observed in CVD patients follow rather than precede disease manifestation and that Treg variation within a physiological range may not – as previously reported - constitute a pre-disposing risk factor for CVD.

Genome-wide non-CpG methylation of the host genome during M. tuberculosis infection

A mammalian cell utilizes DNA methylation to modulate gene expression in response to environmental changes during development and differentiation. Aberrant DNA methylation changes as a correlate to diseased states like cancer, neurodegenerative conditions and cardiovascular diseases have been documented. Here we show genome-wide DNA methylation changes in macrophages infected with the pathogen M. tuberculosis. Majority of the affected genomic loci were hypermethylated in M. tuberculosis infected THP1 macrophages. Hotspots of differential DNA methylation were enriched in genes involved in immune response and chromatin reorganization. Importantly, DNA methylation changes were observed predominantly for cytosines present in non-CpG dinucleotide context. This observation was consistent with our previous finding that the mycobacterial DNA methyltransferase, Rv2966c, targets non-CpG dinucleotides in the host DNA during M. tuberculosis infection and reiterates the hypothesis that pathogenic bacteria use non-canonical epigenetic strategies during infection.

Macrophage-derived chemokine (CCL22) is a novel mediator of lung inflammation following hemorrhage and resuscitation

Resuscitation of patients after hemorrhage often results in pulmonary inflammation and places them at risk for the development of acute respiratory distress syndrome. Our previous data indicate that macrophage-derived chemokine (MDC/CCL22) is elevated after resuscitation, but its direct role in this inflammatory response is unknown. Macrophage-derived chemokine signaling through the C-C chemokine receptor type 4 (CCR4) is implicated in other pulmonary proinflammatory conditions, leading us to hypothesize that MDC may also play a role in the pathogenesis of lung inflammation following hemorrhage and resuscitation. To test this, C57BL/6 mice underwent pressure-controlled hemorrhage followed by resuscitation with lactated Ringer's solution. Pulmonary inflammation and inflammatory cell recruitment were analyzed with histological staining, and serum- and tissue-level cytokines were measured by enzyme-linked immunosorbent assay. Pulmonary inflammation and cell recruitment following hemorrhage and resuscitation were associated with systemic MDC levels. Inhibition of MDC via injection of a specific neutralizing antibody prior to hemorrhage and resuscitation significantly reduced pulmonary levels of the chemotactic cytokines keratinocyte-derived chemokine and macrophage inflammatory proteins 2 and 1α, as well as inflammatory cell recruitment to the lungs. Intravenous administration of recombinant MDC prior to resuscitation augmented pulmonary inflammation and cell recruitment. Histological evaluation revealed the expression of CCR4 within the bronchial epithelium, and in vitro treatment of activated bronchial epithelial cells with MDC resulted in production and secretion of neutrophil chemokines. The present study identifies MDC as a novel mediator of lung inflammation after hemorrhage and resuscitation. Macrophage-derived chemokine neutralization may provide a therapeutic strategy to mitigate this inflammatory response.

Acanthamoeba protease activity promotes allergic airway inflammation via protease-activated receptor 2

Acanthamoeba is a free-living amoeba commonly present in the environment and often found in human airway cavities. Acanthamoeba possesses strong proteases that can elicit allergic airway inflammation. To our knowledge, the aeroallergenicity of Acanthamoeba has not been reported. We repeatedly inoculated mice with Acanthamoeba trophozoites or excretory-secretory (ES) proteins intra-nasally and evaluated symptoms and airway immune responses. Acanthamoeba trophozoites or ES proteins elicited immune responses in mice that resembled allergic airway inflammation. ES proteins had strong protease activity and activated the expression of several chemokine genes (CCL11, CCL17, CCL22, TSLP, and IL-25) in mouse lung epithelial cells. The serine protease inhibitor phenyl-methane-sulfonyl fluoride (PMSF) inhibited ES protein activity. ES proteins also stimulated dendritic cells and enhanced the differentiation of naive T cells into IL-4-secreting T cells. After repeated inoculation of the protease-activated receptor 2 knockout mouse with ES proteins, airway inflammation and Th2 immune responses were markedly reduced, but not to basal levels. Furthermore, asthma patients had higher Acanthamoeba-specific IgE titers than healthy controls and we found Acanthamoeba specific antigen from house dust in typical living room. Our findings suggest that Acanthamoeba elicits allergic airway symptoms in mice via a protease allergen. In addition, it is possible that Acanthamoeba may be one of the triggers human airway allergic disease.

Role of CC chemokine receptor 4 in natural killer cell activation during acute cigarette smoke exposure

Cigarette smoke (CS)-induced lung injury involves innate immune responses. The activation of innate effector cells is thought to require cross talk with dendritic cells (DCs) and macrophages, but the mediators of interaction are unknown. One candidate, CC chemokine receptor 4 (CCR4), is expressed by innate and adaptive effector cells, and its ligands are produced by DCs and macrophages. Using flow cytometry and confocal microscopy, we defined innate responses of lung myeloid DCs, macrophages, and conventional natural killer (NK) cells in mice exposed to CS over 4 days and examined the contribution of CCR4 using CCR4 knockout (CCR4(-/-)) mice. CS affected populations differently, causing an increase in F4/80(+) macrophages, a reduction in parenchymal CD11c(+)CD11b(+)CD103(-) DCs, but no effect on mucosal CD11c(+)CD11b(-)CD103(+) DCs. CS also induced a population of primed/activated CD69(+) NK cells and bronchoepithelial expression of the stress-related NKG2D receptor-activating protein, retinoic acid early transcript 1. CS-exposed CCR4(-/-) mice were similar to controls regarding effects on DCs and macrophages but displayed substantially impaired NK priming/activation and reduced expression of transcripts for interferon gamma, CXCL10, and retinoic acid early transcript 1. Quantitative confocal microscopy revealed that lungs of CS-exposed CCR4(-/-) mice had significantly reduced contacts of NK cells with CD11c(+) cells. These findings demonstrate that acute CS exposure elicits NK cell responses and suggest that CCR4 promotes NK cell priming/activation by mediating contacts with sentinel cells in the lung.

Molecular biology of atherosclerosis

At least 468 individual genes have been manipulated by molecular methods to study their effects on the initiation, promotion, and progression of atherosclerosis. Most clinicians and many investigators, even in related disciplines, find many of these genes and the related pathways entirely foreign. Medical schools generally do not attempt to incorporate the relevant molecular biology into their curriculum. A number of key signaling pathways are highly relevant to atherogenesis and are presented to provide a context for the gene manipulations summarized herein. The pathways include the following: the insulin receptor (and other receptor tyrosine kinases); Ras and MAPK activation; TNF-α and related family members leading to activation of NF-κB; effects of reactive oxygen species (ROS) on signaling; endothelial adaptations to flow including G protein-coupled receptor (GPCR) and integrin-related signaling; activation of endothelial and other cells by modified lipoproteins; purinergic signaling; control of leukocyte adhesion to endothelium, migration, and further activation; foam cell formation; and macrophage and vascular smooth muscle cell signaling related to proliferation, efferocytosis, and apoptosis. This review is intended primarily as an introduction to these key signaling pathways. They have become the focus of modern atherosclerosis research and will undoubtedly provide a rich resource for future innovation toward intervention and prevention of the number one cause of death in the modern world.

CCL17/thymus and activation-regulated chemokine induces calcitonin gene-related peptide in human airway epithelial cells through CCR4

BACKGROUND

Calcitonin gene-related peptide (CGRP) is a potent arterial and venous vasodilator. Increased airway epithelial cell expression of CGRP, together with increased CCL17 expression, was previously observed in a model of provoked asthma in atopic human subjects.

OBJECTIVE

We sought to determine whether CCL17 induces CCR4-dependent CGRP synthesis and secretion by human airway epithelial cells.

METHODS

Human airway epithelial cell lines (BEAS-2B and A549) and human primary airway cells were cultured with CCL17 or various other cytokines, and CGRP expression was measured by using RT-PCR, quantitative immunofluorescence, and enzyme immunoassay. CCR4 expression was determined in cultured cells by using flow cytometry and in bronchial biopsy specimens by using immunohistochemistry.

RESULTS

CCL17 induced a several thousand-fold increase in CGRP mRNA expression and released peptide product from BEAS-2B and A549 cells in a time- and concentration-dependent fashion. Concentration-dependent CCL17-induced release of CGRP by primary human airway epithelial cells was also observed. Under comparable conditions, CCL17 induced greater CGRP release from BEAS-2B cells than either IL-13, a cytokine mixture (TNF-α, GM-CSF, and IL-1), or CCL22. CCR4 was expressed by BEAS-2B and A549 cells and internalized after ligation with CCL17. CCL17-induced CGRP release was inhibited by a specific anti-CCR4 blocking antibody. Bronchial biopsy specimens obtained from healthy volunteers and asthmatic patients before and after provoked asthma all exhibited CCR4 staining of equivalent intensity, indicating that the receptor is constitutively expressed.

CONCLUSIONS

CCL17-induced, CCR4-dependent release of CGRP by human airway epithelial cells represents a novel inflammatory pathway and a possible target in patients with asthma and allergic disease.

Higher serum CCL17 may be a promising predictor of acute exacerbations in chronic hypersensitivity pneumonitis

Background

Recent research has suggested that the Th1 and Th2 chemokine/cytokine axis contributes to the development of chronic hypersensitivity pneumonitis (HP). Acute exacerbations (AE) are significant factors in the prognosis of chronic HP. Little is known, however, about these biomarkers in association with AE in chronic HP patients.

Methods

Fifty-six patients with chronic HP were evaluated, including 14 patients during episodes of AE. Th1 mediators (C-X-C chemokine ligand [CXCL]10 and interferon [IFN]-γ), Th2 mediators (C-C chemokine ligand [CCL]17, interleukin-4, and interleukin-13), and pro-fibrotic mediator (transforming growth factor [TGF]-β) were measured to evaluate the mediators as predictors of AE. C-C chemokine receptor (CCR)4 (receptor for CCL17)-positive lymphocytes were quantified in lung specimens.

Results

Serum CCL17 levels at baseline independently predicted the first episode of AE (HR, 72.0; 95% CI, 5.03-1030.23; p = 0.002). AE was significantly more frequent in the higher-CCL17 group (≥285 pg/ml) than in the lower-CCL17 group (<285 pg/ml) (log-rank test, p = 0.0006; 1-year incidence: higher CCL17 vs. lower CCL17, 14.3% vs. 0.0%). Serum CCL17 levels and CCR4-positive cells during episodes of AE were increased from the baseline (p = 0.01 and 0.031).

Conclusions

Higher serum concentrations of CCL17 at baseline may be predictive of AE in patients with chronic HP, and CCL17 may contribute to the pathology of AE by inducing the accumulation of CCR4-positive lymphocytes in the lungs.

T(H)2-like chemokine patterns correlate with disease severity in patients with recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP), characterized by the recurrent growth of benign tumors of the respiratory tract, is caused by infection with human papillomavirus (HPV), predominantly types 6 and 11. Surgical removal of these lesions can be required as frequently as every 3 to 4 wks to maintain a patent airway. There is no approved medical treatment for this disease. In this study, we have characterized the T(H)2-like chemokine profile (CCL17, CCL18, CCL20, CCL22) in patients with RRP and asked whether it was modulated in patients who had achieved significant clinical improvement. CCL17, CCL18 and CCL22 messenger RNAs (mRNAs) were increased in papillomas compared with clinically normal laryngeal epithelium of the RRP patients. Overall, CCL20 mRNA expression was not increased, but there was intense, selective CCL20 protein expression in the basal layer of the papillomas. Patients with RRP expressed more CCL17 (p = 0.003), CCL18 (p = 0.0003), and CCL22 (p = 0.007) in their plasma than controls. Plasma CCL18 decreased over time in three patients enrolled in a pilot clinical trial of celecoxib, and the decrease occurred in conjunction with clinical improvement. There was a significant correlation between sustained clinical remission in additional patients with RRP and reduced levels of CCL17 (p = 0.01), CCL22 (p = 0.002) and CCL18 (p = 0.05). Thus, the change in expression of these three plasma T(H)2-like chemokines may, with future studies, prove to serve as a useful biomarker for predicting disease prognosis.

Inflammatory biomarkers predict airflow obstruction after exposure to World Trade Center dust

BACKGROUND

The World Trade Center (WTC) collapse on September 11, 2001, produced airflow obstruction in a majority of firefighters receiving subspecialty pulmonary evaluation (SPE) within 6.5 years post-September 11, 2001.

METHODS

In a cohort of 801 never smokers with normal pre-September 11, 2001, FEV1, we correlated inflammatory biomarkers and CBC counts at monitoring entry within 6 months of September 11, 2001, with a median FEV(1) at SPE (34 months; interquartile range, 25-57). Cases of airflow obstruction had FEV(1) less than the lower limit of normal (LLN) (100 of 801; 70 of 100 had serum), whereas control subjects had FEV(1) greater than or equal to LLN (153 of 801; 124 of 153 had serum).

RESULTS

From monitoring entry to SPE years later, FEV(1) declined 12% in cases and increased 3% in control subjects. Case subjects had elevated serum macrophage derived chemokine (MDC), granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor, and interferon inducible protein-10 levels. Elevated GM-CSF and MDC increased the risk for subsequent FEV(1) less than LLN by 2.5-fold (95% CI, 1.2-5.3) and 3.0-fold (95% CI, 1.4-6.1) in a logistic model adjusted for exposure, BMI, age on September 11, 2001, and polymorphonuclear neutrophils. The model had sensitivity of 38% (95% CI, 27-51) and specificity of 88% (95% CI, 80-93).

CONCLUSIONS

Inflammatory biomarkers can be risk factors for airflow obstruction following dust and smoke exposure. Elevated serum GM-CSF and MDC levels soon after WTC exposure were associated with increased risk of airflow obstruction in subsequent years. Biomarkers of inflammation may help identify pathways producing obstruction after irritant exposure.

Epigenetic biomarkers of T-cells in human glioma

Immune factors are thought to influence glioma risk and outcomes, but immune profiling studies to further our understanding of the immune response are limited by current immunodiagnostic methods. We developed a new assay to capture glioma immune biology based on quantitative methylation specific PCR (qMSP) of two T-cell genes (CD3Z: T-cells, and FOXP3: Tregs). Flow cytometry of T-cells correlated well with the CD3Z demethylation assay (r = 0.93; p < 2.2 × 10 (-16) ), demonstrating the validity of the assay. Furthermore, there was a high correlation between qMSP and immunohistochemistry (IHC) in quantifying tumor infiltrating T-cells (r = 0.85; p = 3.4 × 10 (-11) ). Applying our qMSP methods to archival whole blood from 65 glioblastoma multiforme (GBM) cases and 94 non-diseased controls, GBM cases had highly statistically significantly lower T-cells (p = 1.7 × 10 (-9) ) as well as Tregs (p = 5.2 × 10 (-11) ) and a modestly lower ratio of Tregs/T-cells (p = 0.024). Applying the methods to 120 excised glioma tumors, we observed that tumor infiltrating CD3+ T-cells were positively correlated with glioma tumor grade (p = 5.7 × 10 (-7) ), and that Tregs were enriched in tumors compared with peripheral blood indicating active chemoattraction of suppressive Tregs into the tumor compartment. Poorer patient survival was correlated with higher levels of tumor infiltrating T-cells (p = 0.01) and Tregs (p = 0.04). DNA methylation based immunodiagnostics represent a new generation of powerful laboratory tools offering many advantages over conventional methods that will facilitate large clinical epidemiologic studies and capitalize on stored archival blood and tissue banks.

Comparison of WTC dust size on macrophage inflammatory cytokine release in vivo and in vitro

Background

The WTC collapse exposed over 300,000 people to high concentrations of WTC-PM; particulates up to ∼50 mm were recovered from rescue workers’ lungs. Elevated MDC and GM-CSF independently predicted subsequent lung injury in WTC-PM-exposed workers. Our hypotheses are that components of WTC dust strongly induce GM-CSF and MDC in AM; and that these two risk factors are in separate inflammatory pathways.

Methodology/Principal Findings

Normal adherent AM from 15 subjects without WTC-exposure were incubated in media alone, LPS 40 ng/mL, or suspensions of WTC-PM_10–53 or WTC-PM_2.5 at concentrations of 10, 50 or 100 µg/mL for 24 hours; supernatants assayed for 39 chemokines/cytokines. In addition, sera from WTC-exposed subjects who developed lung injury were assayed for the same cytokines. In the in vitro studies, cytokines formed two clusters with GM-CSF and MDC as a result of PM_10–53 and PM_2.5. GM-CSF clustered with IL-6 and IL-12(p70) at baseline, after exposure to WTC-PM_10–53 and in sera of WTC dust-exposed subjects (n = 70) with WTC lung injury. Similarly, MDC clustered with GRO and MCP-1. WTC-PM_10–53 consistently induced more cytokine release than WTC-PM_2.5 at 100 µg/mL. Individual baseline expression correlated with WTC-PM-induced GM-CSF and MDC.

Conclusions

WTC-PM_10–53 induced a stronger inflammatory response by human AM than WTC-PM_2.5. This large particle exposure may have contributed to the high incidence of lung injury in those exposed to particles at the WTC site. GM-CSF and MDC consistently cluster separately, suggesting a role for differential cytokine release in WTC-PM injury. Subject-specific response to WTC-PM may underlie individual susceptibility to lung injury after irritant dust exposure.

Toxic elements in tobacco and in cigarette smoke: inflammation and sensitization

Biochemically and pathologically, there is strong evidence for both atopic and nonatopic airway sensitization, hyperresponsiveness, and inflammation as a consequence of exposure to tobacco mainstream or sidestream smoke particulate. There is growing evidence for the relation between exposure to mainstream and sidestream smoke and diseases resulting from reactive oxidant challenge and inflammation directly as a consequence of the combined activity of neutrophils, macrophages, dendritic cells, eosinophils, basophils, as a humoral immunological consequence of sensitization, and that the metal components of the particulate play a role in adjuvant effects. As an end consequence, carcinogenicity is a known outcome of chronic inflammation. Smokeless tobacco has been evaluated by the IARC as a group 1 carcinogen. Of the many harmful constituents in smokeless tobacco, oral tissue metallothionein gradients suggest that metals contribute to the toxicity from smokeless tobacco use and possibly sensitization. This work reviews and examines work on probable contributions of toxic metals from tobacco and smoke to pathology observed as a consequence of smoking and the use of smokeless tobacco.

Epithelial cells from smokers modify dendritic cell responses in the context of influenza infection

Epidemiologic evidence suggests that cigarette smoking is a risk factor for infection with influenza, but the mechanisms underlying this susceptibility remain unknown. To ascertain if airway epithelial cells from smokers demonstrate a decreased ability to orchestrate an influenza-induced immune response, we established a model using differentiated nasal epithelial cells (NECs) from nonsmokers and smokers, co-cultured with peripheral blood monocyte-derived dendritic cells (mono-DCs) from nonsmokers. NEC/mono-DC co-cultures were infected with influenza A virus and analyzed for influenza-induced immune responses 24 hours after infection. We observed that NECs from smokers, as well as mono-DCs co-cultured with NECs from smokers, exhibited suppressed influenza-induced, interferon-related proteins interferon regulatory factor-7, Toll-like receptor-3, and retinoic acid inducible gene-1, likely because of the suppressed production of IFNα from the NECs of smokers. Furthermore, NEC/mono-DC co-cultures using NECs from smokers exhibited suppressed concentrations of T-cell/natural killer cell chemokine interferon gamma-induced protein 10 (IP-10) after infection with influenza, indicating that NECs from smokers may skew early influenza-induced Th1 responses. In contrast, NEC/mono-DC co-cultures using NEC from smokers contained increased influenza-induced concentrations of the Th2 chemokine thymic stromal lymphopoeitin (TSLP). In addition, NECs from smokers cultured alone had increased influenza-induced concentrations of the Th2 chemokine thymus and activation-regulated chemokine (TARC). Using this model, we demonstrated that in the context of infection with influenza, NECs obtained from smokers create an overall cytokine microenvironment that suppresses the interferon-mediated Th1 response and enhances the TSLP-TARC-mediated Th2 response, with the potential to modify the responses of DCs. Smoking-induced alterations in the Th1/Th2 balance may play a role in developing underlying susceptibilities to respiratory viral infections, and may also promote the likelihood of acquiring Th2 proallergic diseases.

Gene expression profiles identify inflammatory signatures in dendritic cells

Dendritic cells (DCs) constitute a heterogeneous group of antigen-presenting leukocytes important in activation of both innate and adaptive immunity. We studied the gene expression patterns of DCs incubated with reagents inducing their activation or inhibition. Total RNA was isolated from DCs and gene expression profiling was performed with oligonucleotide microarrays. Using a supervised learning algorithm based on Random Forest, we generated a molecular signature of inflammation from a training set of 77 samples. We then validated this molecular signature in a testing set of 38 samples. Supervised analysis identified a set of 44 genes that distinguished very accurately between inflammatory and non inflammatory samples. The diagnostic performance of the signature genes was assessed against an independent set of samples, by qRT-PCR. Our findings suggest that the gene expression signature of DCs can provide a molecular classification for use in the selection of anti-inflammatory or adjuvant molecules with specific effects on DC activity.

Study on correlation of signal molecule genes and their receptor-associated genes with rat liver regeneration

To investigate the effect of signal molecules and their receptor-associated genes on rat liver regeneration (LR) at the transcriptional level, the associated genes were originally obtained by retrieving the databases and related scientific publications; their expression profiles in rat LR were then checked using the Rat Genome 230 2.0 microarray. The LR-associated genes were identified by comparing gene expression difference between partial hepatectomy groups and operation-control groups. A total of 454 genes were proved to be LR related. The genes associated with the seven kinds of signal molecules (steroid hormones, fatty acid derivatives, protein and polypeptide hormones, amino acids and their derivatives, choline, cytokines, and gas signal molecules) were detected to be enriched in a cluster characterized by upregulated expression in LR. The number of genes related to the seven kinds of signal molecules was, in sequence, 63, 27, 100, 102, 16, 166, and 18. The 1027 frequencies of upregulation and 823 frequencies of downregulation in total as well as 42 types of different expression patterns suggest the complex and diverse gene expression changes in LR. It is presumed that signal molecules played an important role in metabolism, inflammation, cell proliferation, growth and differentiation, etc., during rat LR.

Chemotactic mediators of Th1 T-cell trafficking in smokers and COPD patients

Chronic obstructive pulmonary disease (COPD) is smoking-related and associated with increased cytotoxic CD8+ T-cells in the airway. There is a wide range of susceptibility to the damaging effects of cigarette smoke with only a small proportion of smokers progressing to COPD. We have previously reported increased intracellular Th1 cytokines in blood, BAL and intraepithelial CD8+T cells in current and ex-smokers with COPD, whereas healthy smokers showed localized Th1 response in the lung only. We thus hypothesised that Th1-associated chemokines or their receptors on CD8+T-cells may be differentially expressed in the blood of healthy smokers, current smoker COPD subjects and those who had ceased smoking. We investigated chemokines, chemokine receptors and Th1 and cytotoxic T-cell markers in blood and BAL using flow cytometry, ELISA and cytometric bead array. In blood, CXCR3, CCR4, intracellular CCR3 and the Th1 marker 62L(-)CD45RO(+) were increased in both COPD groups and healthy smokers. In contrast, cytotoxic T-cells, ITAC, MIG, IFN-gamma and CCR5 were increased in both COPD groups but not smokers. In BAL, the Th1 marker 62L(-)CD45RO(+), CCR5, CXCR3, IFN-gamma, RANTES, IL-8, MCP-1, MIG and ITAC were increased in both COPD groups and smokers versus controls. Our findings are consistent with systemic inflammation in COPD associated with an increased influx of cytotoxic and Th1 cells into the airway. The differential expression of specific chemokines and their receptors in blood from COPD subjects and healthy smokers suggests that inclusion of these markers in any panel designed for the non-invasive investigation of smokers with a disposition to COPD would be clinically relevant.

Detrimental role of CC chemokine receptor 4 in murine polymicrobial sepsis

CC chemokine receptor 4 (CCR4) and its two ligands, CCL17 and CCL22, are critically involved in different immune processes. In models of lipopolysaccharide-induced shock, CCR4-deficient (CCR4(-/-)) mice showed improved survival rates associated with attenuated proinflammatory cytokine release. Using CCR4(-/-) mice with a C57BL/6 background, this study describes for the first time the role of CCR4 in a murine model of polymicrobial abdominal sepsis, the colon ascendens stent peritonitis (CASP). CASP-induced sepsis led to a massive downregulation of CCR4 in lymphoid and nonlymphoid tissues, whereas the expression of CCL17 and CCL22 was independent of the presence of CCR4. After CASP, CCR4(-/-) animals showed a strongly enhanced bacterial clearance in several organs but not in the peritoneal lavage fluid and the blood. In addition, significantly reduced levels of proinflammatory cytokines/chemokines were measured in organ supernatants as well as in the sera of CCR4(-/-) mice. CCR4 deficiency consequently resulted in an attenuated severity of systemic sepsis and a strongly improved survival rate after CASP or CASP with intervention. Thus, our data provide clear evidence that CCR4 plays a strictly detrimental role in the course of polymicrobial sepsis.

Effects of environmental tobacco smoke exposure on pulmonary immune response in infant monkeys

BACKGROUND

Exposure to environmental tobacco smoke (ETS) in early life has adverse effects on lung development and increases asthma incidence and susceptibility to infection. We have previously reported that perinatal and postnatal exposure to ETS in infant monkeys leads to an impaired T(H)1 immune response in peripheral blood.

OBJECTIVE

Determine whether ETS exposure during the perinatal period alters pulmonary immune maturation in the neonatal lung.

METHODS

Nonhuman primates were exposed to ETS from gestation day 50 to 13 months postnatal age (perinatal ETS) or from 6 to 13 months (postnatal ETS). Control animals were only exposed to filtered air. T(H)1 and T(H)2-related cytokines, chemokines, and their corresponding receptors as well as transcription factors were analyzed in lung tissues at 13 months.

RESULTS

Animals exposed to ETS beginning in utero exhibited more profound alterations in T(H)1 factors compared with animals exposed to ETS beginning at 6 months postnatal age. In perinatal ETS-exposed monkeys, mRNA for IFN-gamma, IL-2, IFN-gamma-inducible protein 10, monokine induced by IFN-gamma, IFN-gamma-inducible T-cell chemoattractant, CXC chemokine receptor 3, IL-12 bioactive p70 subunit, and T-bet were significantly downregulated, whereas in postnatal ETS-exposed monkeys, only IFN-gamma, CXC chemokine receptor 3, and IL-12p70 were significantly downregulated. ETS effects on T(H)2 factors were less apparent and more variable: mRNA for thymus and activation-regulated chemokine was increased, and IL-10 protein was reduced.

CONCLUSIONS

Environmental tobacco smoke exposure during early life enhances a local T(H)2 immunity by impairing normal pulmonary T(H)1 immune maturation. This effect was greater in animals beginning ETS exposure in utero.

Level of Toll-like receptor agonist exposure differentially determines chemokine production in humans

Toll-like receptor (TLR) agonists, ubiquitously present in the environment, are key players in activating synthesis of cytokines and chemokines that control normal and pathophysiological processes, including multiple inflammatory diseases. TLR2 and TLR4 respond to bacterial cell wall products. We examined the impact of TLR activation on human immune capacity using stimuli ranging from the low levels seen in most environments to the high concentrations widely used for in vitro studies. Peripheral blood mononuclear cells from 117 healthy children were activated with lipopolysaccharide (TLR4 ligand) or peptidoglycan (TLR2 ligand) over a million-fold range of concentrations. Resulting interleukin-6, CCL2, and CCL22 production were quantified by ELISA. The intensity of cytokine production elicited was linearly related to the intensity of the stimulus up to maximal responses. In marked contrast, chemokine production was not linearly related to agonist concentration. Responses rose with increasing stimulation, and then were markedly reduced (40%-100%, p < 0.0001) in response to the high levels of TLR stimulation most commonly cited. Thus, the levels of TLR4 and TLR2 agonists typically used for in vitro interrogation of immune capacity yield results clearly distinct from those obtained using commonly occurring environmental levels of TLR ligands. These findings demonstrate the importance of utilizing TLR ligands at concentrations more closely mimicking environmental levels when assessing immune capacity.

Probiotics in the treatment of Japanese cedar pollinosis: a double-blind placebo-controlled trial

BACKGROUND

Probiotic bacteria may be effective in the treatment of allergic inflammation and food allergy, but efficacy and underlying mechanisms remain unclear.

OBJECTIVE

The present study investigated the effects of probiotic strain Bifidobacterium longum BB536 in the treatment of Japanese cedar pollinosis (JCPsis).

METHODS

In a randomized, double-blind, placebo-controlled trial, 44 JCPsis subjects received BB536 or placebo for 13 weeks during the pollen season. Subjective symptoms and self-care measures were recorded daily and blood samples were taken before and during intervention to measure blood levels of parameters related to JCPsis.

RESULTS

BB536 intake was associated with a significant reduction in number of subjects prematurely terminated due to severe symptoms and pollinosis medication (P=0.0057 vs. placebo group). Comparison of subjective symptom scores indicated significant decreases in rhinorrhea, nasal blockage and composite scores in the BB536 group compared with the placebo group. Comparison of medical scores showed marked improvements in all symptoms on BB536 intake. A T-helper type 2 (Th2)-skewed immune response occurring along with pollen dispersion was observed. BB536 significantly suppressed increases in plasma thymus- and activation-regulated chemokine and tended to suppress elevations of Japanese cedar pollen (JCP)-specific IgE.

CONCLUSION

These results suggest the efficacy of BB536 in relieving JCPsis symptoms, probably through the modulation of Th2-skewed immune response.