Macrophage phagocytosis: effects of environmental pollutants, alcohol, cigarette smoke, and other external factors

Airborne Exposure to Pollutants and Mental Health: A Review with Implications for United States Veterans

PURPOSE OF REVIEW

Inhalation of airborne pollutants in the natural and built environment is ubiquitous; yet, exposures are different across a lifespan and unique to individuals. Here, we reviewed the connections between mental health outcomes from airborne pollutant exposures, the biological inflammatory mechanisms, and provide future directions for researchers and policy makers. The current state of knowledge is discussed on associations between mental health outcomes and Clean Air Act criteria pollutants, traffic-related air pollutants, pesticides, heavy metals, jet fuel, and burn pits.

RECENT FINDINGS

Although associations between airborne pollutants and negative physical health outcomes have been a topic of previous investigations, work highlighting associations between exposures and psychological health is only starting to emerge. Research on criteria pollutants and mental health outcomes has the most robust results to date, followed by traffic-related air pollutants, and then pesticides. In contrast, scarce mental health research has been conducted on exposure to heavy metals, jet fuel, and burn pits. Specific cohorts of individuals, such as United States military members and in-turn, Veterans, often have unique histories of exposures, including service-related exposures to aircraft (e.g. jet fuels) and burn pits. Research focused on Veterans and other individuals with an increased likelihood of exposure and higher vulnerability to negative mental health outcomes is needed. Future research will facilitate knowledge aimed at both prevention and intervention to improve physical and mental health among military personnel, Veterans, and other at-risk individuals.

Neuroimmune Activation and Microglia Reactivity in Female Rats Following Alcohol Dependence

The rates of alcohol use disorder among women are growing, yet little is known about how the female brain is affected by alcohol. The neuroimmune system, and specifically microglia, have been implicated in mediating alcohol neurotoxicity, but most preclinical studies have focused on males. Further, few studies have considered changes to the microglial phenotype when examining the effects of ethanol on brain structure and function. Therefore, we quantified microglial reactivity in female rats using a binge model of alcohol dependence, assessed through morphological and phenotypic marker expression, coupled with regional cytokine levels. In a time- and region-dependent manner, alcohol altered the microglial number and morphology, including the soma and process area, and the overall complexity within the corticolimbic regions examined, but no significant increases in the proinflammatory markers MHCII or CD68 were observed. The majority of cytokine and growth factor levels examined were similarly unchanged. However, the expression of the proinflammatory cytokine TNFα was increased, and the anti-inflammatory IL-10, decreased. Thus, female rats showed subtle differences in neuroimmune reactivity compared to past work in males, consistent with reports of enhanced neuroimmune responses in females across the literature. These data suggest that specific neuroimmune reactions in females may impact their susceptibility to alcohol neurotoxicity and other neurodegenerative events with microglial contributions.

Chronic alcohol consumption dysregulates innate immune response to SARS-CoV-2 in the lung

BACKGROUND

Alcohol consumption is widespread with over half of the individuals over 18 years of age in the U.S. reporting alcohol use in the last 30 days. Moreover, 9 million Americans engaged in binge or chronic heavy drinking (CHD) in 2019. CHD negatively impacts pathogen clearance and tissue repair, including in the respiratory tract, thereby increasing susceptibility to infection. Although, it has been hypothesized that chronic alcohol consumption negatively impacts COVID-19 outcomes; the interplay between chronic alcohol use and SARS-CoV-2 infection outcomes has yet to be elucidated.

METHODS

In this study we employed luminex, scRNA sequencing, and flow cytometry to investigate the impact of chronic alcohol consumption on SARS-CoV-2 anti-viral responses in bronchoalveolar lavage cell samples from humans with alcohol use disorder and rhesus macaques that engaged in chronic drinking.

FINDINGS

Our data show that in both humans (n = 6) and macaques (n = 11), the induction of key antiviral cytokines and growth factors was decreased with chronic ethanol consumption. Moreover, in macaques fewer differentially expressed genes mapped to Gene Ontology terms associated with antiviral immunity following 6 month of ethanol consumption while TLR signaling pathways were upregulated.

INTERPRETATION

These data are indicative of aberrant inflammation and reduced antiviral responses in the lung with chronic alcohol drinking.

FUNDING

This study was supported by NIH 1R01AA028735-04 (Messaoudi), U01AA013510-20 (Grant), R24AA019431-14 (Grant), R24AA019661 (Burnham), P-51OD011092 (ONPRC core grant support). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

Nanotoxicity of multifunctional stoichiometric cobalt oxide nanoparticles (SCoONPs) with repercussions toward apoptosis, necrosis, and cancer necrosis factor (TNF-α) at nano-biointerfaces

Introduction

Apoptosis, necrosis, and cancer necrosis factor (TNF-a) are all impacted by the nanotoxicity of multifunctional stoichiometric cobalt oxide nanoparticles (SCoONPs) at nano-biointerfaces. The creation of multi-functional nanoparticles has had a considerable impact on the transport of drugs and genes, nanotheranostics (in-vivo imaging, concurrent diagnostics), interventions for external healing, the creation of nano-bio interfaces, and the instigation of desired changes in nanotherapeutics.

Objectives

The quantitative structure-activity relationships, chemical transformations, biological interactions as well as toxicological analyses are considered as main objectives. Discrete dimensions of SCoNPs-cell interaction interfaces, their characteristic physical features (size, shape, shell structure, and surface chemistry), impact on cell proliferation and differentiation are the key factors responsible for nanotoxicity.

Methods

The development of multi-functional nanoparticles has been significant in drug/gene delivery, nanotheranostics (in-vivo imaging, coinciding diagnostics), and external healing interventions, designing a nano-bio interface, as well as inciting desired alterations in nanotherapeutics. Every so often, the cellular uptake of multi-functional cobalt [Co, CoO, Co2(CO)8 and Co3O4] nanoparticles (SCoONPs) influences cellular mechanics and initiates numerous repercussions (oxidative stress, DNA damage, cytogenotoxicity, and chromosomal damage) in pathways, including the generation of dysregulating factors involved in biochemical transformations.

Results

The concerns and influences of multifunctional SCoNPs on different cell mechanisms (mitochondria impermeability, hydrolysis of ATP, the concentration of Ca2+, impaired calcium clearance, defective autophagy, apoptosis, and necrosis), and interlinked properties (adhesion, motility, and internalization dynamics, role in toxicity, surface hydrophilic and hydrophobicity, biokinetics and biomimetic behaviors of biochemical reactions) have also been summarized. SCoONPs have received a lot of interest among the nanocarriers family because of its advantageous qualities such as biodegradability, biocompatibility, nontoxicity, and nonimmunogenicity.

Conclusion

Various applications, such as bio-imaging, cell labeling, gene delivery, enhanced chemical stability, and increased biocompatibility, concerning apoptosis, necrosis, and nano-bio interfaces, along with suitable examples. In this analysis, the multi-functional cobalt [Co, CoO, Co2(CO)8 and Co3O4] nanoparticles (SCoNPs) intricacies (cytogenotoxicity, clastogenicity, and immunomodulatory), nanotoxicity, and associated repercussions have been highlighted and explained.

Diverse roles of lung macrophages in the immune response to influenza A virus

Influenza viruses are one of the major causes of human respiratory infections and the newly emerging and re-emerging strains of influenza virus are the cause of seasonal epidemics and occasional pandemics, resulting in a huge threat to global public health systems. As one of the early immune cells can rapidly recognize and respond to influenza viruses in the respiratory, lung macrophages play an important role in controlling the severity of influenza disease by limiting viral replication, modulating the local inflammatory response, and initiating subsequent adaptive immune responses. However, influenza virus reproduction in macrophages is both strain- and macrophage type-dependent, and ineffective replication of some viral strains in mouse macrophages has been observed. This review discusses the function of lung macrophages in influenza virus infection in order to better understand the pathogenesis of the influenza virus.

Chronic alcohol consumption dysregulates innate immune response to SARS-CoV-2 in the lung

Alcohol consumption is widespread with over half of the individuals over 18 years of age in the U.S. reporting alcohol use in the last 30 days. Moreover, 9 million Americans engaged in binge or chronic heavy drinking (CHD) in 2019. CHD negatively impacts pathogen clearance and tissue repair, including in the respiratory tract, thereby increasing susceptibility to infection. Although, it has been hypothesized that chronic alcohol consumption negatively impacts COVID-19 outcomes; the interplay between chronic alcohol use and SARS-CoV-2 infection outcomes has yet to be elucidated. Therefore, in this study we investigated the impact of chronic alcohol consumption on SARS-CoV-2 anti-viral responses in bronchoalveolar lavage cell samples from humans with alcohol use disorder and rhesus macaques that engaged in chronic drinking. Our data show that in both humans and macaques, the induction of key antiviral cytokines and growth factors was decreased with chronic ethanol consumption. Moreover, in macaques fewer differentially expressed genes mapped to Gene Ontology terms associated with antiviral immunity following 6 month of ethanol consumption while TLR signaling pathways were upregulated. These data are indicative of aberrant inflammation and reduced antiviral responses in the lung with chronic alcohol drinking.

Integrated single cell analysis shows chronic alcohol drinking disrupts monocyte differentiation in the bone marrow niche

Chronic alcohol drinking rewires circulating monocytes and tissue-resident macrophages towards heightened inflammatory states with compromised anti-microbial defenses. As these effects remain consistent in short-lived monocytes after a 1-month abstinence period it is unclear whether these changes are restricted to the periphery or mediated through alterations in the progenitor niche. To test this hypothesis, we profiled monocytes/macrophages and hematopoietic stem cell progenitors (HSCP) of the bone marrow compartment from rhesus macaques after 12 months of ethanol consumption using a combination of functional assays and single cell genomics. Bone marrow-resident monocytes/macrophages from ethanol-consuming animals exhibited heightened inflammation. Differentiation of HSCP in vitro revealed skewing towards monocytes expressing neutrophil-like markers with heightened inflammatory responses to bacterial agonists. Single cell transcriptional analysis of HSCPs showed reduced proliferation but increased inflammatory markers in mature myeloid progenitors. We observed transcriptional signatures associated with increased oxidative and cellular stress as well as oxidative phosphorylation in immature and mature myeloid progenitors. Single cell analysis of the chromatin landscape showed altered drivers of differentiation in monocytes and progenitors. Collectively, these data indicate that chronic ethanol drinking results in remodeling of the transcriptional and epigenetic landscapes of the bone marrow compartment leading to altered functions in the periphery.

Green tea extract ameliorates macrophage-driven emphysematous lesions in chronic obstructive pulmonary disease induced by cigarette smoke condensate

Chronic obstructive pulmonary disease (COPD) is an important lung disease characterized by complicated symptoms including emphysema. We aimed to explore the mechanisms underlying the protective effect of green tea extract (GTE) on cigarette smoke condensate (CSC)-induced emphysema by demonstrating the reduction of macrophage-induced protease expression through GTE treatment in vivo and in vitro. Mice were intranasally administered 50 mg/kg CSC once a week for 4 weeks, and doses of 100 or 300 mg/kg GTE were administered orally once daily for 4 weeks. GTE significantly reduced macrophage counts in bronchoalveolar lavage fluid and emphysematous lesions in lung tissues in CSC-exposed mice. In addition, GTE suppressed CSC-induced extracellular signal-regulated kinase (ERK)/activator protein (AP)-1 phosphorylation followed by matrix metalloproteinases (MMP)-9 expression as revealed by western blotting, immunohistochemistry, and zymography in CSC-instilled mice. These underlying mechanisms related to reduced protease expression were confirmed in NCI-H292 cells stimulated by CSC. Taken together, GTE effectively inhibits macrophage-driven emphysematous lesions induced by CSC treatment, and these protective effects of GTE are closely related to the ERK/AP-1 signaling pathway, followed by a reduced protease/antiprotease imbalance. These results suggest that GTE can be used as a supplementary agent for the prevention of emphysema progression in COPD patients.

Role of Adenylyl Cyclase Type 7 in Functions of BV-2 Microglia

To assess the role of adenylyl cyclase type 7 (AC7) in microglia's immune function, we generated AC7 gene knockout (AC7 KO) clones from a mouse microglial cell line, BV-2, using the CRISPR-Cas9 gene editing system. The ability of BV-2 cells to generate cAMP and their innate immune functions were examined in the presence or absence of ethanol. The parental BV-2 cells showed robust cAMP production when stimulated with prostaglandin-E₁ (PGE₁) and ethanol increased cAMP production in a dose-dependent manner. AC7 KO clones of BV-2 cells showed diminished and ethanol-insensitive cAMP production. The phagocytic activity of the parental BV-2 cells was inhibited in the presence of PGE₁; AC7 KO BV-2 cells showed lower and PGE₁-insensitive phagocytic activity. Innate immune activities of the parental BV-2 cells, including bacterial killing, nitric oxide synthesis, and expression of arginase 1 and interleukin 10 were activated as expected with small effects of ethanol. However, the innate immune activities of AC7 KO cells were either drastically diminished or not detected. The data presented suggest that AC7 has an important role in the innate immune functions of microglial cells. AC7's involvement in ethanol's effects on immune functions remains unclear. Further studies are needed.

Use of Photobiomodulation Combined with Fibrin Sealant and Bone Substitute Improving the Bone Repair of Critical Defects

In this preclinical protocol, an adjunct method is used in an attempt to overcome the limitations of conventional therapeutic approaches applied to bone repair of large bone defects filled with scaffolds. Thus, we evaluate the effects of photobiomodulation therapy (PBMT) on the bone repair process on defects filled with demineralized bovine bone (B) and fibrin sealant (T). The groups were BC (blood clot), BT (B + T), BCP (BC + PBMT), and BTP (B + T + PBMT). Microtomographically, BC and BCP presented a hypodense cavity with hyperdense regions adjacent to the border of the wound, with a slight increase at 42 days. BT and BTP presented discrete hyperdensing areas at the border and around the B particles. Quantitatively, BCP and BTP (16.96 ± 4.38; 17.37 ± 4.38) showed higher mean bone density volume in relation to BC and BT (14.42 ± 3.66; 13.44 ± 3.88). Histologically, BC and BCP presented deposition of immature bone at the periphery and at 42 days new bone tissue became lamellar with organized total collagen fibers. BT and BTP showed inflammatory infiltrate along the particles, but at 42 days, it was resolved, mainly in BTP. In the birefringence analysis, BT and BTP, the percentage of red birefringence increased (9.14% to 20.98% and 7.21% to 27.57%, respectively), but green birefringence was similar in relation to 14 days (3.3% to 3.5% and 3.5% to 4.2%, respectively). The number of osteocytes in the neoformed bone matrix proportionally reduced in all evaluated groups. Immunostaining of bone morphogenetic protein (BMP—2/4), osteocalcin (OCN), and vascular endothelial growth factor (VEGF) were higher in BCP and BTP when compared to the BC and BT groups (p < 0.05). An increased number of TRAP positive cells (tartrate resistant acid phosphatase) was observed in BT and BTP. We conclude that PBMT positively influenced the repair of bone defects filled with B and T.

The key player in the pathogenesis of environmental influence of systemic lupus erythematosus: Aryl hydrocarbon receptor

The aryl hydrocarbon receptor was previously known as an environmental receptor that modulates the cellular response to external environmental changes. In essence, the aryl hydrocarbon receptor is a cytoplasmic receptor and transcription factor that is activated by binding to the corresponding ligands, and they transmit relevant information by binding to DNA, thereby activating the transcription of various genes. Therefore, we can understand the development of certain diseases and discover new therapeutic targets by studying the regulation and function of AhR. Several autoimmune diseases, including systemic lupus erythematosus (SLE), have been connected to AhR in previous studies. SLE is a classic autoimmune disease characterized by multi-organ damage and disruption of immune tolerance. We discuss here the homeostatic regulation of AhR and its ligands among various types of immune cells, pathophysiological roles, in addition to the roles of various related cytokines and signaling pathways in the occurrence and development of SLE.

Ethanol Consumption Induces Nonspecific Inflammation and Functional Defects in Alveolar Macrophages

Chronic alcohol drinking is associated with increased susceptibility to viral and bacterial respiratory pathogens. In this study, we use a rhesus macaque model of voluntary ethanol self-administration to study the effects of long-term alcohol drinking on the immunological landscape of the lung. We report a heightened inflammatory state in alveolar macrophages (AMs) obtained from ethanol (EtOH)-drinking animals that is accompanied by increased chromatin accessibility in intergenic regions that regulate inflammatory genes and contain binding motifs for transcription factors AP-1, IRF8, and NFKB p-65. In line with these transcriptional and epigenetic changes at the basal state, AMs from EtOH-drinking animals generate elevated inflammatory mediator responses to lipopolysaccharides and respiratory syncytial virus. However, the transcriptional analysis revealed an inefficient induction of interferon-stimulated genes with EtOH in response to the respiratory syncytial virus, suggesting disruption of antimicrobial defenses. Correspondingly, AMs from EtOH-drinking animals exhibited transcriptional shifts indicative of increased oxidative stress and oxidative phosphorylation, which was coupled with higher cytosolic reactive oxygen species and mitochondrial potential. This heightened oxidative stress state was accompanied by decreased ability to phagocytose bacteria. Bulk RNA and assay for transposase-accessible chromatin sequencing data further revealed reduced expression and chromatin accessibility of loci associated with tissue repair and maintenance with chronic EtOH drinking. Similarly, analysis of single-cell RNA sequencing data revealed shifts in cell states from tissue maintenance to inflammatory responses with EtOH. Collectively, these data provide novel insight into mechanisms by which chronic EtOH drinking increases susceptibility to infection in patients with alcohol use disorders.

Ethanol Intoxication Impairs Respiratory Function and Bacterial Clearance and Is Associated With Neutrophil Accumulation in the Lung After Streptococcus pneumoniae Infection

Alcohol consumption is commonplace in the United States and its prevalence has increased in recent years. Excessive alcohol use is linked to an increased risk of infections including pneumococcal pneumonia, mostly commonly caused by Streptococcus pneumoniae. In addition, pneumonia patients with prior alcohol use often require more intensive treatment and longer hospital stays due to complications of infection. The initial respiratory tract immune response to S. pneumoniae includes the production of pro-inflammatory cytokines and chemokines by resident cells in the upper and lower airways which activate and recruit leukocytes to the site of infection. However, this inflammation must be tightly regulated to avoid accumulation of toxic by-products and subsequent tissue damage. A majority of previous work on alcohol and pneumonia involve animal models utilizing high concentrations of ethanol or chronic exposure and offer conflicting results about how ethanol alters immunity to pathogens. Further, animal models often employ a high bacterial inoculum which may overwhelm the immune system and obscure results, limiting their applicability to the course of human infection. Here, we sought to determine how a more moderate ethanol exposure paradigm affects respiratory function and innate immunity in mice after intranasal infection with 10⁴ colony forming units of S. pneumoniae. Ethanol-exposed mice displayed respiratory dysfunction and impaired bacterial clearance after infection compared to their vehicle-exposed counterparts. This altered response was associated with increased gene expression of neutrophil chemokines Cxcl1 and Cxcl2 in whole lung homogenates, elevated concentrations of circulating granulocyte-colony stimulating factor (G-CSF), and higher neutrophil numbers in the lung 24 hours after infection. Taken together, these findings suggest that even a more moderate ethanol consumption pattern can dramatically modulate the innate immune response to S. pneumoniae after only 3 days of ethanol exposure and provide insight into possible mechanisms related to the compromised respiratory immunity seen in alcohol consumers with pneumonia.

An assessment of vaping-induced inflammation and toxicity: A feasibility study using a 2-stage zebrafish and mouse platform

It is currently understood that tobacco smoking is a major cause of pulmonary disease due to pulmonary/lung inflammation. However, due to a highly dynamic market place and an abundance of diverse products, less is known about the effects of e-cigarette (E-cig) use on the lung. In addition, varieties of E-cig liquids (e-liquids), which deliver nicotine and numerous flavor chemicals into the lungs, now number in the 1000s. Thus, a critical need exists for safety evaluations of these E-cig products. Herein, we employed a "2-stage in vivo screening platform" (zebrafish to mouse) to assess the safety profiles of e-liquids. Using the zebrafish, we collected embryo survival data after e-liquid exposure as well as neutrophil migration data, a key hallmark for a pro-inflammatory response. Our data indicate that certain e-liquids induce an inflammatory response in our zebrafish model and that e-liquid exposure alone results in pro-inflammatory lung responses in our C57BL/6J model, data collected from lung staining and ELISA analysis, respectively, in the mouse. Thus, our platform can be used as an initial assessment to ascertain the safety profiles of e-liquid using acute inflammatory responses (zebrafish, Stage 1) as our initial metric followed by chronic studies (C57BL/6J, Stage 2).

<i>Lactococcus lactis</i> subsp. <i>cremoris</i> C60 induces macrophages activation that enhances CD4+ T cell-based adaptive immunity

Lactococcus lactis subsp. cremoris C60 is a probiotic strain that induces diverse functional modifications in immune cells. In this report, as a novel effect of C60 on myeloid lineage cells, we show that C60 enhances the immunological function of macrophages that consequently promotes CD4+ T cell activity in an antigen-dependent manner. Heat-killed (HK) C60 induced the production of pro-inflammatory cytokines in thioglycolate-elicited peritoneal macrophages (TPMs) much stronger than Toll-like receptor (TLR) ligand stimulation. The HK-C60 treatment also augmented the expression of antigen-presenting and co-stimulatory molecules, such as major histocompatibility complex (MHC) class II, CD80, and CD86, as well as antigen uptake in TPMs. These HK-C60-mediated functional upregulations in TPMs resulted in the promotion of CD4+ T cell activation in an antigen-dependent manner. Interestingly, the TPMs that originated from the mice fed the HK-C60 diet showed pre-activated characteristics, which was confirmed by the upregulation of cytokine production and antigen presentation-related molecule expression under lipopolysaccharide (LPS) stimulation. Furthermore, the antigen-dependent CD4+ T cell activation was also enhanced by the TPMs. This implied that antigen presentation activity was enhanced in the TPMs that originated from the HK-C60 diet mice. Thus, C60 effectively upregulates the immunological function of macrophages that directly connects to CD4+ T cell-based adaptive immunity.

The Association of Alcohol Use Disorder with Perioperative Complications following Primary Total Hip Arthroplasty

Purpose

Alcohol use disorder is a leading mental health disorder in the United States. Few studies evaluating the association of alcohol use disorder following primary total hip arthroplasty (THA) have been reported. Therefore, the purpose of this study was to determine whether patients with alcohol use disorder undergoing primary THA have higher rates of: 1) in-hospital lengths of stay (LOS); 2) complications (medical/implant-related); and 3) costs.

Materials and Methods

Using a nationwide claims database from January 1st, 2005 to March 31st, 2014, patients with alcohol use disorder undergoing primary THA were identified and matched to a comparison group according to age, sex, and various comorbidities, resulting in 230,467 patients who were included in the study (n=38,416) and a matched-cohort (n=192,051). Outcomes of interest included comparison of LOS, 90-day medical and 2-year implant-related complications, and costs. A P-value less than 0.002 was considered statistically significant.

Results

Patients with alcohol use disorder had longer in-hospital LOS (4 days vs 3 days; P<0.0001) as well as higher frequency and odds ratio (OR) of 90-day medical (45.94% vs 12.25%; OR, 2.89; P<0.0001) and 2-year implant-related complications (17.71% vs 8.46%; OR, 1.97; P<0.0001). Patients in the study group incurred higher 90-day costs of care ($17,492.63 vs $14,921.88; P<0.0001).

Conclusion

With the growing prevalence of alcohol use disorder in the United States, the current investigation can be utilized to evaluate the need for interventions prior to THA which can potentially minimize the rates of morbidity and mortality within this population.

Role of Particulate Matter from Afghanistan and Iraq in Deployment-Related Lung Disease

Approximately 3 million United States military personnel and contractors were deployed to Southwest Asia and Afghanistan over the past two decades. After returning to the United States, many developed persistent respiratory symptoms, including those due to asthma, rhinosinusitis, bronchiolitis, and others, which we collectively refer to as deployment-related lung diseases (DRLD). The mechanisms of different DRLD have not been well defined. Limited studies from us and others suggest that multiple factors and biological signaling pathways contribute to the onset of DRLD. These include, but are not limited to, exposures to high levels of particulate matter (PM) from sandstorms, burn pit combustion products, improvised explosive devices, and diesel exhaust particles. Once inhaled, these hazardous substances can activate lung immune and structural cells to initiate numerous cell-signaling pathways such as oxidative stress, Toll-like receptors, and cytokine-driven cell injury (e.g., interleukin-33). These biological events may lead to a pro-inflammatory response and airway hyperresponsiveness. Additionally, exposures to PM and other environmental hazards may predispose military personnel and contractors to more severe disease due to the interactions of those hazardous materials with subsequent exposures to allergens and cigarette smoke. Understanding how airborne exposures during deployment contribute to DRLD may identify effective targets to alleviate respiratory diseases and improve quality of life in veterans and active duty military personnel.

Transcriptional, Epigenetic, and Functional Reprogramming of Monocytes From Non-Human Primates Following Chronic Alcohol Drinking

Chronic heavy drinking (CHD) of alcohol is a known risk factor for increased susceptibility to bacterial and viral infection as well as impaired wound healing. Evidence suggests that these defects are mediated by a dysregulated inflammatory response originating from myeloid cells, notably monocytes and macrophages, but the mechanisms remain poorly understood. Our ability to study CHD is impacted by the complexities of human drinking patterns and behavior as well as comorbidities and confounding risk factors for patients with alcohol use disorders. To overcome these challenges, we utilized a translational rhesus macaque model of voluntary ethanol self-administration that closely recapitulates human drinking patterns and chronicity. In this study, we examined the effects of CHD on blood monocytes in control and CHD female macaques after 12 months of daily ethanol consumption. While monocytes from CHD female macaques generated a hyper-inflammatory response to ex vivo LPS stimulation, their response to E. coli was dampened. In depth scRNA-Seq analysis of purified monocytes revealed significant shifts in classical monocyte subsets with accumulation of cells expressing markers of hypoxia (HIF1A) and inflammation (NFkB signaling pathway) in CHD macaques. The increased presence of monocyte subsets skewed towards inflammatory phenotypes was complemented by epigenetic analysis, which revealed higher accessibility of promoter regions that regulate genes involved in cytokine signaling pathways. Collectively, data presented in this manuscript demonstrate that CHD shifts classical monocyte subset composition and primes the monocytes towards a more hyper-inflammatory response to LPS, but compromised pathogen response.

Role of Innate Immune System in Environmental Lung Diseases

The lung mucosa functions as a principal barrier between the body and inhaled environmental irritants and pathogens. Precise and targeted surveillance mechanisms are required at this lung-environment interface to maintain homeostasis and preserve gas exchange. This is performed by the innate immune system, a germline-encoded system that regulates initial responses to foreign irritants and pathogens. Environmental pollutants, such as particulate matter (PM), ozone (O₃), and other products of combustion (NO₂, SO₃, etc.), both stimulate and disrupt the function of the innate immune system of the lung, leading to the potential for pathologic consequences. PURPOSE OF REVIEW: The purpose of this review is to explore recent discoveries and investigations into the role of the innate immune system in responding to environmental exposures. This focuses on mechanisms by which the normal function of the innate immune system is modified by environmental agents leading to disruptions in respiratory function. RECENT FINDINGS: This is a narrative review of mechanisms of pulmonary innate immunity and the impact of environmental exposures on these responses. Recent findings highlighted in this review are categorized by specific components of innate immunity including epithelial function, macrophages, pattern recognition receptors, and the microbiome. Overall, the review supports broad impacts of environmental exposures to alterations to normal innate immune functions and has important implications for incidence and exacerbations of lung disease. The innate immune system plays a critical role in maintaining pulmonary homeostasis in response to inhaled air pollutants. As many of these agents are unable to be mitigated, understanding their mechanistic impact is critical to develop future interventions to limit their pathologic consequences.

Lipopolysaccharide-Enhanced Responses against Aryl Hydrocarbon Receptor in FcgRIIb-Deficient Macrophages, a Profound Impact of an Environmental Toxin on a Lupus-Like Mouse Model

Fc gamma receptor IIb (FcgRIIb) is the only inhibitory-FcgR in the FcgR family, and FcgRIIb-deficient (FcgRIIb^−/−) mice develop a lupus-like condition with hyper-responsiveness against several stimulations. The activation of aryl hydrocarbon receptor (Ahr), a cellular environmental sensor, might aggravate activity of the lupus-like condition. As such, 1,4-chrysenequinone (1,4-CQ), an Ahr-activator, alone did not induce supernatant cytokines from macrophages, while the 24 h pre-treatment by lipopolysaccharide (LPS), a representative inflammatory activator, prior to 1,4-CQ activation (LPS/1,4-CQ) predominantly induced macrophage pro-inflammatory responses. Additionally, the responses from FcgRIIb^−/− macrophages were more prominent than wild-type (WT) cells as determined by (i) supernatant cytokines (TNF-α, IL-6, and IL-10), (ii) expression of the inflammation associated genes (NF-κB, aryl hydrocarbon receptor, iNOS, IL-1β and activating-FcgRIV) and cell-surface CD-86 (a biomarker of M1 macrophage polarization), and (iii) cell apoptosis (Annexin V), with the lower inhibitory-FcgRIIb expression. Moreover, 8-week-administration of 1,4-CQ in 8 week old FcgRIIb^−/− mice, a genetic-prone lupus-like model, enhanced lupus characteristics as indicated by anti-dsDNA, serum creatinine, proteinuria, endotoxemia, gut-leakage (FITC-dextran), and glomerular immunoglobulin deposition. In conclusion, an Ahr activation worsened the disease severity in FcgRIIb^−/− mice possibly through the enhanced inflammatory responses. The deficiency of inhibitory-FcgRIIb in these mice, at least in part, prominently enhanced the pro-inflammatory responses. Our data suggest that patients with lupus might be more vulnerable to environmental pollutants.

Ethanol modulates the effector functions of human monocyte-derived macrophages in response to Paracoccidioides brasiliensis yeast cells

We aimed to investigate the effects of ethanol and its metabolites (β-hydroxybutyrate and sodium acetate) in the effector functions of macrophages in response to Paracoccidioides brasiliensis yeast cells and to determine their influence in the development of the adaptive response. Purified peripheral blood monocytes were differentiated into macrophages and were treated with ethanol, β-hydroxybutyrate, and sodium acetate, and stimulated with P. brasiliensis yeast cells and evaluated for their phenotypic characteristics, functional activity, and capability to induce T cells activation/differentiation. We found that the ethanol treatment diminished the expression of HLA-AB, HLA-DR, CD80, and CD86, modulating the expression of dectin-1, as well as Syk phosphorylation. The ethanol treatment increased the phagocytic activity, expression of CD206, and IL-10 production; however, reduced ROS production, fungicidal activity, caspase-1 cleavage, and IL-1β and IL-6 production. Our data also showed that the presence of ethanol reduced the differentiation of Th1 and Th17 cells and increased the frequency of Th2 cells. Our results indicated that ethanol exposure could suppress effector function of macrophages, possibly leading to the polarization of M2 macrophages. The ethanol modulates the expression of costimulatory and antigen-presentation molecules and interferes with the NLRP3 inflammasome. Altogether, these alterations affect the development of the adaptive response, decreasing the frequency of IL-17, IL-22, and IFN- γ producing cells, and increasing the frequency of IL-4 producing cells. Therefore, exposure to ethanol can impair the capability of macrophages to exert their effector functions and activate the acquired response related to resistance to P. brasiliensis infection.

IL-33/ST2 signaling modulates Afghanistan particulate matter induced airway hyperresponsiveness in mice

Increased symptoms of asthma-like respiratory illnesses have been reported in soldiers returning from tours of duty in Afghanistan. Inhalation of desert particulate matter (PM) may contribute to this deployment-related lung disease (DRLD), but little is known about disease mechanisms. The IL-33 signaling pathway, including its receptor ST2, has been implicated in the pathogenesis of lung diseases including asthma, but its role in PM-mediated airway dysfunction has not been studied. The goal of this study was to investigate whether IL-33/ST2 signaling contributes to airway dysfunction in preclinical models of lung exposure to Afghanistan PM (APM). Wild-type (WT) and ST2 knockout (KO) mice on the BALB/C background were oropharyngeally instilled with a single dose of saline or 50 μg of APM in saline. Airway hyperresponsiveness (AHR) and inflammation were assessed after 24 h. In WT mice, a single APM exposure induced AHR and neutrophilic inflammation. Unlike the WT mice, ST2 KO mice that lack the receptor for IL-33 did not demonstrate AHR although airway neutrophilic inflammation was comparable to the WT mice. Oropharyngeal delivery of a soluble ST2 decoy receptor in APM-exposed WT mice significantly blocked AHR. Additional data in mouse tracheal epithelial cell and lung macrophage cultures demonstrated a role of APM-induced IL-33/ST2 signaling in suppression of regulator of G protein signaling 2 (RGS2), a gene known to protect against bronchoconstriction. We present for the first time that APM may increase AHR, one of the features of asthma, in part through the IL-33/ST2/RGS2 pathway.

Is macrophages heterogeneity important in determining COVID-19 lethality?

COVID-19 (coronavirus disease 2019) pandemic due to infection with SARS-CoV-2 has led to the death of thousands of adults worldwide. It is now clear that the hyper-inflammatory response triggered by SARS-CoV-2 plays a major role in disease severity and lethality of the infection. Macrophages are innate immune cells that sense and respond to infections by producing a plethora of inflammatory molecules and by interacting with other inflammatory cells. Therefore, macrophages may be diriment on eliminating pathogens and promoting organ repair. However, macrophages can be a major player of the so called cytokine storm and may be damaging to the tissues. It is believed that macrophage activation syndrome is induced by SARS-CoV to be lethal. Surprisingly and fortunately few children die from COVID-19. For instance, in Italy, out of more than 30.000 deaths for COVID-19, three are children. Therefore, we must wonder why? Are macrophages different in children compared to adults? In my opinion they are different. It has been demonstrated that macrophages populate the lung in three “developmental waves”, and it has been suggested that similar waves may be observed in other important organs, such as the heart and kidney. It is most likely that macrophages heterogeneity is involved in determining the severity. There are no doubts that macrophages are important in determining life or death in these patients. Comparing macrophages of children with those of adults with different degrees of disease severity is, therefore, mandatory.

Toxicant Disruption of Immune Defenses: Potential Implications for Fetal Membranes and Pregnancy

In addition to providing a physical compartment for gestation, the fetal membranes (FM) are an active immunological barrier that provides defense against pathogenic microorganisms that ascend the gravid reproductive tract. Pathogenic infection of the gestational tissues (FM and placenta) is a leading known cause of preterm birth (PTB). Some environmental toxicants decrease the capacity for organisms to mount an immune defense against pathogens. For example, the immunosuppressive effects of the widespread environmental contaminant trichloroethylene (TCE) are documented for lung infection with Streptococcus zooepidemicus. Group B Streptococcus (GBS; Streptococcus agalactiae) is a bacterial pathogen that is frequently found in the female reproductive tract and can colonize the FM in pregnant women. Work in our laboratory has demonstrated that a bioactive TCE metabolite, S-(1, 2-dichlorovinyl)-L-cysteine (DCVC), potently inhibits innate immune responses to GBS in human FM in culture. Despite these provocative findings, little is known about how DCVC and other toxicants modify the risk for pathogenic infection of FM. Infection of the gestational tissues (FM and placenta) is a leading known cause of PTB, therefore toxicant compromise of FM ability to fight off infectious microorganisms could significantly contribute to PTB risk. This Perspective provides the current status of understanding of toxicant-pathogen interactions in FM, highlighting knowledge gaps, challenges, and opportunities for research that can advance protections for maternal and fetal health.

Reactive oxygen species-mediated cytoplasmic stiffening impairs the phagocytic ability of the macrophage

The phagocytic ability of macrophages empowers them to enforce innate immunity. RAW264.7, THP-1 and peripheral blood mononuclear cell-derived macrophages display considerable variability with regards to their phagocytic ability. We identify the underlying causes that attenuate the phagocytic abilities of a macrophage. Deformability of the cytoplasm and cortex influences the macrophage's phagocytic ability, and macrophages use the large cell-to-cell variability of their cytoplasmic stiffness to modulate their phagocytic ability. We find that the more-deformable macrophages have a higher phagocytic ability than those that are less deformable. Further, the subcellular spatial variability of cortex stiffness gives rise to more-deformable subdomains on the membrane for pathogen ingestion. We report a previously unknown negative-feedback loop that is triggered by the phagocytic oxidative burst. Macrophages utilize the excess reactive oxygen species to stiffen the cytoplasm, reducing their phagocytic propensity. In organisms, ageing or pathological conditions impair the phagocytic ability of macrophages. Our findings identify the targets that could potentially be utilized for restoring the phagocytic ability of the defunct macrophages.

Cigarette Smoke Exposure Induces Retrograde Trafficking of CFTR to the Endoplasmic Reticulum

Chronic obstructive pulmonary disease (COPD), which is most commonly caused by cigarette smoke (CS) exposure, is the third leading cause of death worldwide. The cystic fibrosis transmembrane conductance regulator (CFTR) is an apical membrane anion channel that is widely expressed in epithelia throughout the body. In the airways, CFTR plays an important role in fluid homeostasis and helps flush mucus and inhaled pathogens/toxicants out of the lung. Inhibition of CFTR leads to mucus stasis and severe airway disease. CS exposure also inhibits CFTR, leading to the decreased anion secretion/hydration seen in COPD patients. However, the underlying mechanism is poorly understood. Here, we report that CS causes CFTR to be internalized in a clathrin/dynamin-dependent fashion. This internalization is followed by retrograde trafficking of CFTR to the endoplasmic reticulum. Although this internalization pathway has been described for bacterial toxins and cargo machinery, it has never been reported for mammalian ion channels. Furthermore, the rapid internalization of CFTR is dependent on CFTR dephosphorylation by calcineurin, a protein phosphatase that is upregulated by CS. These results provide new insights into the mechanism of CFTR internalization, and may help in the development of new therapies for CFTR correction and lung rehydration in patients with debilitating airway diseases such as COPD.

Disseminated Invasive Candidiasis in an Immunocompetent Host

Health care providers should consider a nonbacterial source as the causative agent for invasive candidiasis infection in immunocompetent patients.

Chronic alcohol abuse affects the clinical course and outcome of community-acquired bacterial meningitis

The aim of the study was to determine the effect of chronic alcohol abuse on the course and outcome of bacterial meningitis (BM). We analyzed records of patients with BM who were hospitalized between January 2010 and December 2017 in the largest neuroinfection center in Poland. Out of 340 analyzed patients, 45 (13.2%) were alcoholics. Compared with non-alcoholics, alcoholics were more likely to present with seizures (p < 0.001), scored higher on the Sequential Organ Failure Assessment (SOFA) (p = 0.002) and lower on the Glasgow Coma Scale (GCS) (p < 0.001), and had worse outcome as measured by the Glasgow Outcome Score (GOS) (p < 0.001). Furthermore, alcoholics were less likely to complain of headache (p < 0.001) and nausea/vomiting (p = 0.005) and had lower concentration of glucose in cerebrospinal fluid (CSF) (p = 0.025). In the multiple logistic regression analysis, alcoholism was associated with lower GCS (p = 0.036), presence of seizures (p = 0.041), male gender (p = 0.042), and absence of nausea/vomiting (p = 0.040). Furthermore, alcoholism (p = 0.031), lower GCS score (p = 0.001), and higher blood urea concentration (p = 0.018) were independently associated with worse outcome measured by GOS. Compared with non-alcoholics, chronic alcohol abusers are more likely to present with seizures, altered mental status, and higher SOFA score and have an increased risk of unfavorable outcome. In multivariate analysis, seizures and low GCS were independently associated with alcoholism, while alcoholism was independently associated with worse outcome.

Ethanol Exposure Impairs AMPK Signaling and Phagocytosis in Human Alveolar Macrophages: Role of Ethanol Metabolism

BACKGROUND

Chronic alcohol consumption impairs alveolar macrophage's (AM) function and increases risk for developing lung infection and pneumonia. However, the mechanism and metabolic basis of alcohol-induced AM dysfunction leading to lung infection are not well defined, but may include altered ethanol (EtOH) and reactive oxygen species metabolism and cellular energetics. Therefore, oxidative stress, endoplasmic reticulum (ER) stress, the formation of fatty acid ethyl esters [FAEEs, nonoxidative metabolites of EtOH], AMP-activated protein kinase (AMPK) signaling, and phagocytic function were examined in freshly isolated AM incubated with EtOH.

METHODS

AMs separated from bronchoalveolar lavage fluid samples obtained from normal volunteers were incubated with EtOH for 24 hours. AMPK signaling and ER stress were assessed using Western blotting, FAEEs by GC-MS, oxidative stress by immunofluorescence using antibodies to 4-hydroxynonenal, and phagocytosis by latex beads. Oxidative stress was also measured in EtOH-treated AMs with/without AMPK activator [5-aminoimidazole-4-carboxamide ribonucleotide (AICAR)] or inhibitor (Compound C), and in AMs incubated with FAEEs. mRNA expression for interleukins (IL-6 and IL-8), monocyte chemoattractant protein (MCP)-1, and transforming growth factor (TGF)-β was measured in AM treated with EtOH or FAEEs using RT-PCR.

RESULTS

EtOH exposure to AM increased oxidative stress, ER stress, and synthesis of FAEEs, decreased phosphorylated AMPK, and impaired phagocytosis. Attenuation or exacerbation of EtOH-induced oxidative stress by AICAR or Compound C, respectively, suggests a link between AMPK signaling, EtOH metabolism, and related oxidative stress. The formation of FAEEs may contribute to EtOH-induced oxidative stress as FAEEs also produced concentration-dependent oxidative stress. An increased mRNA expression of IL-6, IL-8, and MCP-1 by FAEEs is key finding to suggest a metabolic basis of EtOH-induced inflammatory response.

CONCLUSIONS

EtOH-induced impaired phagocytosis, oxidative stress, ER stress, and dysregulated AMPK signaling are plausibly associated with the formation of FAEEs and may participate in the pathogenesis of nonspecific pulmonary inflammation.

Influence of experimental alcoholism on the repair process of bone defects filled with beta-tricalcium phosphate

This study evaluated the effect of ethanol on the repair in calvaria treated with beta-tricalcium phosphate (β-TCP). Forty rats were distributed into 2 groups: Water group (CG, n = 20) and Alcohol Group (AG, n = 20), which received 25% ethanol ad libitum after an adaptation period of 3 weeks. After 90 days of liquid diet, the rats were submitted to a 5.0 mm bilateral craniotomy in the parietal bones; the left parietal was filled with β-TCP (CG-TCP and AG-TCP) and the contralateral only with blood clot (CG-Clot and AG-Clot). The animals were killed after 10, 20, 40 and 60 days. The groups CG-Clot and AG-Clot showed similar pattern of bone formation with a gradual and significant increase in the amount of bone in CG-Clot (22.17 ± 3.18 and 34.81 ± 5.49) in relation to AG-Clot (9.35 ± 5.98 and 21.65 ± 6.70) in periods of 20-40 days, respectively. However, in the other periods there was no statistically significant difference. Alcohol ingestion had a negative influence on bone formation, even with the use of β-TCP, exhibiting slow resorption and replacement by fibrous tissue, with 16% of bone formation within 60 days in AG-TCP, exhibiting immature bone tissue with predominance of disorganized collagen fibers. Defects in CG-TCP showed bone tissue with predominance of lamellar arrangement filling 39% of the original defect. It can be concluded that chronic ethanol consumption impairs the ability to repair bone defects, even with the use of a β-TCP biomaterial.

Characteristics of patients with endometrial hyperplasia under different air quality index conditions

OBJECTIVE

Air pollution has been widely recognized to pose a threat to health. Urban outdoor air pollution was listed as the 14th biggest risk factor for global deaths in 2004 in the Global Health Risks report published by the World Health Organization in 2009. Many past studies have indicated that exposure to environmental contaminants promotes changes in the internal mechanisms of diseases, including the infection of various systems in the body, hormonal changes, and vascular proliferation. These changes may be related to the severity of endometrial hyperplasia. Therefore, this study used the air quality monitoring data of the Environmental Protection Administration (EPA) to examine the effects of air pollutant concentration on patients with endometrial hyperplasia.

MATERIALS AND METHODS

This population-based nationwide study used data for 2002-2013 from the National Health Insurance Research Database of Taiwan. Patients who developed endometrial hyperplasia before 2002 were excluded. In total, 14,883 patients with endometrial hyperplasia were tracked. The exposure levels and air quality index (AQI) values in this study were based on the taiwan air quality monitoring network data collected by the EPA from 2000 to 2013. The data were further divided into the good air quality group (AQI ≤ 50) and poor air quality group (AQI > 50). The study used linear regression model to estimate the correlation linking air pollutant concentration with endometrial hyperplasia.

RESULTS

The results indicated that, in comparison to endometrial hyperplasia patients who were exposed to air with good quality, those exposed to air with poor quality had a higher average age (p < 0.001) and higher proportion of living in southern Taiwan (p < 0.001), as well as higher rates of diabetes (p < 0.001), hyperlipidemia (p < 0.001), hypertension, cerebrovascular diseases (p = 0.024), cerebral vascular accidents (p = 0.024), and chronic kidney disease (p < 0.001).

CONCLUSION

The patients with endometrial hyperplasia in poor AQI area had severe comorbidity. Thus, attention must be paid to the improvement of air quality and the implementation of preventive measures against contaminants.

Association of childhood pulmonary tuberculosis with exposure to indoor air pollution: a case control study

Background

Crude measures of exposure to indicate indoor air pollution have been associated with the increased risk for acquiring tuberculosis. Our study aimed to determine an association between childhood pulmonary tuberculosis (PTB) and exposure to indoor air pollution (IAP), based on crude exposure predictors and directly sampled and modelled pollutant concentrations.

Methods

In this case control study, children diagnosed with PTB were compared to children without PTB. Questionnaires about children’s health; and house characteristics and activities (including household air pollution) and secondhand smoke (SHS) exposure were administered to caregivers of participants. A subset of the participants’ homes was sampled for measurements of PM₁₀ over a 24-h period (n = 105), and NO₂ over a period of 2 to 3 weeks (n = 82). IAP concentrations of PM₁₀ and NO₂ were estimated in the remaining homes using predictive models. Logistic regression was used to look for association between IAP concentrations, crude measures of IAP, and PTB.

Results

Of the 234 participants, 107 were cases and 127 were controls. Pollutants concentrations (μg/m³) for were PM₁₀ median: 48 (range: 6.6–241) and NO₂ median: 16.7 (range: 4.5–55). Day-to-day variability within- household was large. In multivariate models adjusted for age, sex, socioeconomic status, TB contact and HIV status, the crude exposure measures of pollution viz. cooking fuel type (clean or dirty fuel) and SHS showed positive non-significant associations with PTB. Presence of dampness in the household was a significant risk factor for childhood TB acquisition with aOR of 2.4 (95% CI: 1.1–5.0). The crude exposure predictors of indoor air pollution are less influenced by day-to-day variability. No risk was observed between pollutant concentrations and PTB in children for PM₁₀ and NO₂.

Conclusion

Our study suggests increased risk of childhood tuberculosis disease when children are exposed to SHS, dirty cooking fuel, and dampness in their homes. Yet, HIV status, age and TB contact are the most important risk factors of childhood PTB in this population.

Effects of Underlying Liver Disease on 30-Day Outcomes After Posterior Lumbar Fusion

OBJECTIVE

To examine the effects of underlying liver disease on 30-day postoperative complications after elective posterior lumbar fusion (PLF).

METHODS

We performed a retrospective American College of Surgeons National Surgical Quality Improvement Program study of patients who had undergone elective PLF from 2011 to 2014. The patients were divided into 2 groups stratified by the presence of liver disease, assessed using the Model for End-stage Liver Disease plus sodium score (liver disease, ≥10; no liver disease, <10). The baseline patient and operative characteristics were compared between the 2 groups using univariate analysis. Subsequent multivariate regression analysis adjusted for differences in baseline characteristics was performed to identify 30-day postoperative complications independently associated with liver disease.

RESULTS

Of 2965 patients, 55.9% had underlying liver disease. Those with liver disease were more frequently aged >65 years, male, and underweight or overweight and had had American Society of Anesthesiologists class ≥3, diabetes, pulmonary comorbidity, cardiac comorbidity, renal comorbidity, bleeding disorder, preoperative dyspnea at rest, and a prolonged operative time. On univariate analysis, patients with liver disease had a greater incidence of cardiac complications, pulmonary complications, renal complications, blood transfusion, sepsis, urinary tract infection, and prolonged hospitalization. On adjusted multivariate regression analysis, liver disease was independently associated with renal complications, pulmonary complications, sepsis, urinary tract infection, prolonged hospitalization, and blood transfusion.

CONCLUSIONS

As the long-term survival of patients with liver disease continues to increase, a better understanding of the relationship between liver dysfunction and surgical outcomes is needed. The identification of modifiable risk factors would allow them to be addressed and optimized preoperatively to decrease the incidence and severity of complications and improve patient outcomes after PLF.

Particulate matter air pollution and respiratory impact on humans and animals

Air pollution is now fully acknowledged to be a public health problem and a social issue. Particulate matter (PM) concentration has been linked with several clinical manifestations of pulmonary and cardiovascular diseases and is associated with morbidity and mortality induced by respiratory diseases both in human and animals. Current research on airborne particle-induced health effects investigates the critical characteristics of particulate matter that determine their biological effects. Scientific evidence assessed that the size of the airborne particles and their surface area determine the potential to elicit inflammatory injury, oxidative damage, and other biological effects. Thus, the present review paper aims to summarize the current evidences and findings on the effect of air pollution on lung function in both humans and animals.

Hepatitis C Virus-Infected Apoptotic Hepatocytes Program Macrophages and Hepatic Stellate Cells for Liver Inflammation and Fibrosis Development: Role of Ethanol as a Second Hit

Hepatocyte apoptosis is a crucially important mechanism for liver disease pathogenesis, and the engulfment of apoptotic bodies (AB) by non-parenchymal cells serves as a leading mechanism of inflammation and fibrosis progression. Previously, we have shown that hepatitis C virus (HCV) and alcohol metabolites induce massive apoptosis in hepatocytes and the spread of HCV-infection to the neighboring uninfected cells. Here, we hypothesize that the capturing of AB by non-parenchymal cells, macrophages and hepatic stellate cells (HSC) changes their phenotype to promote inflammation and fibrosis. In this regard, we generated AB from Huh7.5^CYP2E1 (RLW) cells also treated with an acetaldehyde-generating system (AGS) and incubated them with human monocyte-derived macrophages (MDMs) and HSC (LX2 cells). Activation of inflammasomes and pro-fibrotic markers has been tested by RT-PCR and linked to HCV expression and AGS-induced lipid peroxidation in RLW cells. After exposure to AB we observed activation of inflammasomes in MDMs, with a higher effect of AB HCV+, further enhanced by incubation of MDMs with ethanol. In HSC, activation of inflammasomes was modest; however, HCV and AGS exposure induced pro-fibrotic changes. We conclude that HCV as well as lipid peroxidation-adducted proteins packaged in AB may serve as a vehicle for delivery of parenchymal cell cargo to non-parenchymal cells to activate inflammasomes and pro-fibrotic genes and promote liver inflammation and fibrosis.

Suppression of the interleukin-1ß-induced inflammatory response of human Chang liver cells by acute and subacute exposure to alcohol: an in vitro study

Aim

To evaluate protective immunosuppressive dose and time-dependent effects of ethanol in an in vitro model of acute inflammation in human Chang liver cells.

Method

The study was performed in 2016 and 2017 in the research laboratory of the Department of Trauma, Hand and Reconstructive Surgery, the University Hospital of the Goethe-University Frankfurt. Chang liver cells were stimulated with either interleukin (IL)-1β or IL-6 and subsequently treated with low-dose ethanol (85 mmol/L) or high-dose ethanol (170 mmol/L) for one hour (acute exposure) or 72 hours (subacute exposure). IL-6 and IL-1β release were determined by enzyme-linked immunosorbent assay. Neutrophil adhesion to Chang liver monolayers, production of reactive oxygen species, and apoptosis or necrosis were analyzed.

Results

Contrary to high-dose ethanol, acute low-dose ethanol exposure significantly reduced IL-1β-induced IL-6 and IL-6-induced IL-1β release (P < 0.05). Subacute ethanol exposure did not change proinflammatory cytokine release. Acute low-dose ethanol exposure significantly decreased inflammation-induced formation of reactive oxygen species (P < 0.05) and significantly improved cell survival (P < 0.05). Neither acute nor subacute high-dose ethanol exposure significantly changed inflammation-induced changes in reactive oxygen species or survival. Acute and subacute ethanol exposure, independently of the dose, significantly decreased neutrophil adhesion to inflamed Chang liver cells (P < 0.05).

Conclusion

Acute treatment of inflamed Chang liver cells with ethanol showed its immunosuppressive potential. However, the observed effects were limited to low-dose setting, indicating the relevance of ethanol dose in the modulation of inflammatory cell response.

Dendritic cells trigger imbalance of Th1/Th2 cells in silica dust exposure rat model via MHC-II, CD80, CD86 and IL-12

Silicosis is one of the most common occupational respiratory diseases caused by inhaling silica dust over a prolonged period of time, and the progression of silicosis is accompanied with chronic inflammation and progressive pulmonary fibrosis, in which dendritic cells (DCs), the most powerful antigen presentation cell (APC) in the immune response, play a crucial role. To investigate the role of DCs in the development of silicosis, we established an experimental silicosis rat model and examined the number of DCs and alveolar macrophages (AMs) in lung tissues using immunofluorescence over 84 days. Additionally, to obtain an overview of the immunological changes in rat lung tissues, a series of indicators including Th1/Th2 cells, IFN-γ, IL-4, MHC-II, CD80/86 and IL-12 were detected using flow cytometry and an enzyme-linked immunosorbent assay (ELISA) as well as a real-time polymerase chain reaction (PCR) assay. We observed that the number of DCs slightly increased at the inflammatory stage, and it increased significantly at the final stage of fibrosis. Polarization of Th1 cells and IFN-γ expressions were dominant during the inflammatory stage, whereas polarization of Th2 cells and IL-4 expressions were dominant during the fibrotic stage. The subsequent mechanistic study found that the expressions of MHC-II, CD80/86 and IL-12, which are the key molecules that connect DCs and Th cells, changed dynamically in the experimental silicosis rat model. The data obtained in this study indicated that the increase in DCs may contribute to polarization of Th1/Th2 cells via MHC-II, CD80/86, and IL-12 in silica dust-exposed rats.

Cigarette smoke extract interferes with placenta macrophage functions: A new mechanism to compromise placenta functions?

The success of pregnancy depends on the maternal immune system's ability to promote tolerance and host defense. This equilibrium is compromised in inflammatory and infectious impairment of placenta. Smoking during pregnancy exposes the fetus to severe complications which might result from an alteration in placenta macrophages (pMφ) functions. In this study, we assessed the effect of cigarette smoke extract (CSE) on the functions of third trimester pMφs.CSE inhibited particles uptake and the formation of multinucleated giant cells, a recently reported property of pMφs based on their ability to fuse in vitro. These alterations were associated with a CSE-induced abnormal activation of pMφs, which was characterized by an increased release of TNF, interleukin (IL)-33, and decreased IL-6 and IL-10 release. Furthermore, CSE enhanced the expression of metalloproteinase genes known to be involved in tissue remodeling. This effect of CSE on pMφs was specific because CSE affected circulating monocytes in a different way. Finally, we showed that nicotine affected in part the functional properties of pMφs. Taken together, these results showed that CSE modulated the functional activity of pMφs, which may compromise pregnancy.

Transcriptome analysis of alcohol-treated microglia reveals downregulation of beta amyloid phagocytosis

BACKGROUND

Microglial activation contributes to the neuropathology associated with chronic alcohol exposure and withdrawal, including the expression of inflammatory and anti-inflammatory genes. In the current study, we examined the transcriptome of primary rat microglial cells following incubation with alcohol alone, or alcohol together with a robust inflammatory stimulus.

METHODS

Primary microglia were prepared from mixed rat glial cultures. Cells were incubated with 75 mM ethanol alone or with proinflammatory cytokines ("TII": IL1β, IFNγ, and TNFα). Isolated mRNA was used for RNAseq analysis and qPCR. Effects of alcohol on phagocytosis were determined by uptake of oligomeric amyloid beta.

RESULTS

Alcohol induced nitrite production in control cells and increased nitrite production in cells co-treated with TII. RNAseq analysis of microglia exposed for 24 h to alcohol identified 312 differentially expressed mRNAs ("Alc-DEs"), with changes confirmed by qPCR analysis. Gene ontology analysis identified phagosome as one of the highest-ranking KEGG pathways including transcripts regulating phagocytosis. Alcohol also increased several complement-related mRNAs that have roles in phagocytosis, including C1qa, b, and c; C3; and C3aR1. RNAseq analysis identified over 3000 differentially expressed mRNAs in microglia following overnight incubation with TII; and comparison to the group of Alc-DEs revealed 87 mRNAs modulated by alcohol but not by TII, including C1qa, b, and c. Consistent with observed changes in phagocytosis-related mRNAs, the uptake of amyloid beta1-42, by primary microglia, was reduced by alcohol.

CONCLUSIONS

Our results define alterations that occur to microglial gene expression following alcohol exposure and suggest that alcohol effects on phagocytosis could contribute to the development of Alzheimer's disease.

Smoking and outcomes in kidney transplant recipients: a post hoc survival analysis of the FAVORIT trial

Background

Tobacco use remains an international health problem with between 10% and 40% of adults currently using tobacco. Given the rising number of patients either awaiting or having received a kidney transplant and the absence of smoking cessation as the criterion for transplantation in guidelines, we explored the association between smoking status and clinical outcomes in kidney transplant recipients.

Patients and methods

In this post hoc analysis of the Folic Acid for Vascular Outcome Reduction in Transplant trial, the associations between smoking status, defined as never having smoked, formerly or currently smoking, and both all-cause mortality and graft survival were assessed using Cox proportional hazards models. Fatal events were centrally adjudicated into prespecified categories: all-cause, cardiovascular and non-cardiovascular causes. Graft loss was defined as return to dialysis or retransplantation. Clinical Trials URL: http://www.clinicaltrials.gov/show/NCT00064753.

Results

Among 4110 transplant recipients, there were 451 current smokers and 1611 former smokers. The mortality rate per 100 patient-years was 4.0 (71 deaths) for smokers, 3.5 (226 deaths) for former smokers and 2.4 (116 deaths) for never smokers. Hazard ratio for mortality for current smokers was 1.70 (CI=1.26–2.29, p=0.001) and for former smokers was 1.21 (0.98–1.50, p=0.08) with 1.0 representing never smokers. As the number of cardiovascular deaths was similar in each group (all p>0.3), the differences between groups was driven by non-cardiovascular death rates. Current smokers (2.39; 1.62–3.61, p<0.001) and former smokers (1.50; 1.12–2.01, p=0.007) had increased hazard of non-cardiovascular death. Kidney allograft failure was more likely in current smokers than in either former or never smokers (3.5, 2.1 and 2.0 per 100 patient-years, p<0.001, adjusted hazard ratio 1.49 and 1.05, respectively).

Conclusion

Continued smoking was associated with >100% increased risk of non-cardiovascular death, 70% greater risk of all-cause mortality and a 50% greater risk of graft loss, a risk not seen in former smokers. These findings confirm previous non-adjudicated observations that smoking is associated with adverse clinical outcomes and suggest that more emphasis should be placed on smoking cessation prior to kidney transplantation.

Summary of the 2016 Alcohol and Immunology Research Interest Group (AIRIG) meeting

On November 18, 2016 the 21st annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the Center for Translational Research and Education at Loyola University Chicago's Health Sciences Campus in Maywood, IL. The 2016 meeting focused broadly on alcohol and inflammation, epigenetics, and the microbiome. The four plenary sessions of the meeting were Alcohol, Inflammation, and Immunity; Alcohol and Epigenetics; Alcohol, Transcriptional Regulation, and Epigenetics; and Alcohol, Intestinal Mucosa, and the Gut Microbiome. Presentations in all sessions of the meeting explored putative underlying causes for chronic diseases and mortality associated with alcohol consumption, shedding light on future work and potential therapeutic targets to alleviate the negative effects of alcohol misuse.

Phytotherapeutic effects of the fruits of Poncirus trifoliata (L.) Raf. on cancer, inflammation, and digestive dysfunction

Poncirus trifoliata (L.) Raf. belongs to the family Rutaceae in the genus Poncirus. Its fruits are widely used to alleviate symptoms of various disorders. The mature fruit (MF) possesses anticancer and antiinflammatory activities. Extracts of the dried, immature fruit, Poncirus fructus (PF) are widely used as a traditional medicine for ameliorating symptoms of digestive dysfunction in East Asia. Molecular and cellular mechanisms underlying the effects of MF and PF extracts on cancer, inflammation, and gastrointestinal disorders have been extensively studied in the past decade. This review summarizes recent findings on the anticancer and antiinflammatory effects of MF and the prokinetic effects of PF. Although the therapeutic effects of MF and PF have been clearly elucidated, in-depth further clinical studies are still required to completely verify the clinical efficacy and safety of the fruits of P. trifoliata (L.) Raf.

The effect of different workplace nanoparticles on the immune systems of employees

Currently, nanoparticles are widely present in the environment and are being used in various industrial technologies. Nanoparticles affect immune functions, causing different immune responses. The aim of the current study was to evaluate several cytokines, interleukin (IL)-1b, IL-6, IL-8, tumour necrosis factor-a (TNF-α), interferon-γ, adhesive molecule sICAM-1, macrophage inhibitory protein 1a (MIP1a) and secretory immunoglobulin A, in nasal lavage fluid and in the peripheral blood of healthy subjects exposed to workplace nanoparticles. Thirty-six employees from three different environments were examined: 12 from a metalworking company, 12 from a woodworking company and 12 office workers. The nanoparticles in the different workplaces were detected in the air in the immediate vicinity of the employees. The particle number concentration and surface area values were significantly higher in the workplaces of the metal- and woodworking industries, but concentrations of mass were lower (the measurements were performed by an electrical low-pressure impactor ELPI+). Energy dispersive X-ray spectroscopy (EDS, an attachment to a high-resolution SEM) was used to provide elemental analysis or chemical characterization of the dust particles in a low-vacuum field-free mode operating at a potential of 15 kV spot 3.0. The technique used provided quantitative and spatial analyses of the distribution of elements through mapping (two to three parallel measurements) and point analysis (four to five parallel measurements). Samples from the metal industry contained more ultramicroscopic and nanometric particles, e.g. toxic metals such as Zn, Mn and Cr, and fewer microscopic dust particles. The nasal lavage and peripheral blood were taken at the beginning and the end of the working week, when immune indices were measured. Our data showed a statistically significant increased level of the pro-inflammatory cytokine TNF-α in serum in both exposed groups compared with office workers as well as a higher level of TNF-α in workers from the woodworking company compared with the metalworking employees. We found an elevated level of IL-6 in the exposed groups as well as an elevated level of IL-8 in the nasal lavage in woodworking employees after work.

Alcohol, aging, and innate immunity

The global population is aging: in 2010, 8% of the population was older than 65 y, and that is expected to double to 16% by 2050. With advanced age comes a heightened prevalence of chronic diseases. Moreover, elderly humans fair worse after acute diseases, namely infection, leading to higher rates of infection-mediated mortality. Advanced age alters many aspects of both the innate and adaptive immune systems, leading to impaired responses to primary infection and poor development of immunologic memory. An often overlooked, yet increasingly common, behavior in older individuals is alcohol consumption. In fact, it has been estimated that >40% of older adults consume alcohol, and evidence reveals that >10% of this group is drinking more than the recommended limit by the National Institute on Alcohol Abuse and Alcoholism. Alcohol consumption, at any level, alters host immune responses, including changes in the number, phenotype, and function of innate and adaptive immune cells. Thus, understanding the effect of alcohol ingestion on the immune system of older individuals, who are already less capable of combating infection, merits further study. However, there is currently almost nothing known about how drinking alters innate immunity in older subjects, despite innate immune cells being critical for host defense, resolution of inflammation, and maintenance of immune homeostasis. Here, we review the effects of aging and alcohol consumption on innate immune cells independently and highlight the few studies that have examined the effects of alcohol ingestion in aged individuals.

Human Lung Mononuclear Phagocytes in Health and Disease

The lungs are vulnerable to attack by respiratory insults such as toxins, allergens, and pathogens, given their continuous exposure to the air we breathe. Our immune system has evolved to provide protection against an array of potential threats without causing collateral damage to the lung tissue. In order to swiftly detect invading pathogens, monocytes, macrophages, and dendritic cells (DCs)-together termed mononuclear phagocytes (MNPs)-line the respiratory tract with the key task of surveying the lung microenvironment in order to discriminate between harmless and harmful antigens and initiate immune responses when necessary. Each cell type excels at specific tasks: monocytes produce large amounts of cytokines, macrophages are highly phagocytic, whereas DCs excel at activating naïve T cells. Extensive studies in murine models have established a division of labor between the different populations of MNPs at steady state and during infection or inflammation. However, a translation of important findings in mice is only beginning to be explored in humans, given the challenge of working with rare cells in inaccessible human tissues. Important progress has been made in recent years on the phenotype and function of human lung MNPs. In addition to a substantial population of alveolar macrophages, three subsets of DCs have been identified in the human airways at steady state. More recently, monocyte-derived cells have also been described in healthy human lungs. Depending on the source of samples, such as lung tissue resections or bronchoalveolar lavage, the specific subsets of MNPs recovered may differ. This review provides an update on existing studies investigating human respiratory MNP populations during health and disease. Often, inflammatory MNPs are found to accumulate in the lungs of patients with pulmonary conditions. In respiratory infections or inflammatory diseases, this may contribute to disease severity, but in cancer patients this may improve clinical outcomes. By expanding on this knowledge, specific lung MNPs may be targeted or modulated in order to attain favorable responses that can improve preventive or treatment strategies against respiratory infections, lung cancer, or lung inflammatory diseases.

Low-level arsenic causes chronic inflammation and suppresses expression of phagocytic receptors

The impact of chronic low-level groundwater arsenic (As) exposure [in the range above the WHO-recommended limit of 10 μg/L but ≤50 μg/L (permissible limit of As for many Asian countries)] was investigated for cross talk of inflammatory changes and expression of phagocytic receptors of exposed rural women (N, 45) from districts of 24 Parganas (south) and in matched control groups (N, 43) [As ≤10 μg/L] from the same district. Systemic inflammation was evident from the upregulated levels of pro-inflammatory mediators like tumor necrosis factor-α (TNF-α); interleukins (ILs) like IL-6, IL-8, and IL-12; and C-reactive protein (CRP) in the sera and upregulated expression of protein kinase B phosphorylated at ser473 (pAKTser473)/nuclear factor-κB (NF-κB)/TNF-α axis in the leukocytes of exposed women with respect to control. We found that low-dose As exposure apart from inflicting inflammation altered the expression of phagocytic receptors-Fcγ receptors (FcγRs) and complement receptors (CRs). The leukocytes of the low-As-exposed women exhibited suppression of CD64, CD35, and CD11b and increased expression of CD16 with respect to control. Groundwater As showed a negative correlation with CD64 expression on monocytes [Pearson's r, -0.8205; 95% confidence interval (CI), -0.8789 to -0.7379] and granulocytes [r, -0.7635; 95% CI, -0.8388 to -0.6595] and a positive correlation with CD16 on granulocytes [r, 0.8363; 95% CI, 0.7599 to 0.8899]. A negative correlation of groundwater As was also observed with expression of CD35 on granulocytes [r, -0.8780; 95% CI, -0.9185 to -0.8192] and monocytes [r, -0.7778; 95% CI, -0.8490 to -0.6790] and CD11b on monocytes [r, -0.6035; 95% CI, -0.7218 to -0.4511]. Therefore, it may be indicated that chronic low-level As exposure (11-50 μg/L) not only evoked chronic inflammatory changes but also suppressed the expression of FcγRs and CRs in the exposed women. This, in turn, may lead to susceptibility towards pathogenic infections or in long run may even contribute towards chronic inflammatory diseases including cancer.

MicroRNA Cargo of Extracellular Vesicles from Alcohol-exposed Monocytes Signals Naive Monocytes to Differentiate into M2 Macrophages

Membrane-coated extracellular vesicles (EVs) released by cells can serve as vehicles for delivery of biological materials and signals. Recently, we demonstrated that alcohol-treated hepatocytes cross-talk with immune cells via exosomes containing microRNA (miRNAs). Here, we hypothesized that alcohol-exposed monocytes can communicate with naive monocytes via EVs. We observed increased numbers of EVs, mostly exosomes, secreted by primary human monocytes and THP-1 monocytic cells in the presence of alcohol in a concentration- and time-dependent manner. EVs derived from alcohol-treated monocytes stimulated naive monocytes to polarize into M2 macrophages as indicated by increased surface expression of CD68 (macrophage marker), M2 markers (CD206 (mannose receptor) and CD163 (scavenger receptor)), secretion of IL-10, and TGFβ and increased phagocytic activity. miRNA profiling of the EVs derived from alcohol-treated THP-1 monocytes revealed high expression of the M2-polarizing miRNA, miR-27a. Treatment of naive monocytes with control EVs overexpressing miR-27a reproduced the effect of EVs from alcohol-treated monocytes on naive monocytes and induced M2 polarization, suggesting that the effect of alcohol EVs was mediated by miR-27a. We found that miR-27a modulated the process of phagocytosis by targeting CD206 expression on monocytes. Importantly, analysis of circulating EVs from plasma of alcoholic hepatitis patients revealed increased numbers of EVs that contained high levels of miR-27a as compared with healthy controls. Our results demonstrate the following: first, alcohol increases EV production in monocytes; second, alcohol-exposed monocytes communicate with naive monocytes via EVs; and third, miR-27a cargo in monocyte-derived EVs can program naive monocytes to polarize into M2 macrophages.