Neutrophil Infiltration Research Articles

Stratified Mucin-producing Lesions of the Anus

Primary anal cancers are rare and typically driven by high-risk human papillomavirus (HPV) infection. Though squamous cell carcinoma is most common, a spectrum of HPV-related nonsquamous anogenital neoplasms with similarities to cervical stratified mucin-producing carcinoma has been reported. In this study, we mined our institutional archives to characterize the clinicopathologic features of this emerging entity. Six cases were identified from the files at 2 institutions, including 4 cases of invasive stratified mucin-producing carcinoma and 2 stratified mucin-producing intraepithelial lesions (SMILE). Four patients were women, and the mean age was 70 years. Patients presented with rectal/anal mass or polyp, rectal bleeding or pain, weight loss, or at the time of screening colonoscopy. Tumors displayed histologic features as described in the gynecologic tract. Cases of invasive stratified mucinous carcinoma showed infiltrative tumor nests with variable intracytoplasmic mucin, peripheral palisading, prominent apoptosis, and neutrophilic infiltrate. One invasive stratified mucinous carcinoma associated with high grade glandular dysplasia, whereas 1 SMILE was next to conventional low-grade squamous intraepithelial lesion. All lesions stained with p16 showed block-like p16 expression. HPV in situ hybridization was performed in 5 cases, 4 of which were positive; one was interpreted as equivocal. Follow-up information, available in 4 patients, revealed 1 local recurrence followed by death due to unrelated causes in a patient with invasive stratified mucin-producing carcinoma. We report the first series of HPV-associated primary anal stratified mucin-producing neoplasms analogous to those seen in the gynecologic tract, further broadening the spectrum of HPV-related anal neoplasia.

Comparative Assessment of Beeswax Alcohol and Coenzyme Q10 (CoQ10) to Prevent Liver Aging, Organ Damage, and Oxidative Stress in Hyperlipidemic Zebrafish Exposed to D-Galactose: A 12-Week Dietary Intervention.

The current study was designed to compare in vivo efficacy between beeswax alcohol (BWA) and coenzyme Q10 (CoQ10) to treat fatty liver changes, oxidative stress, and damages in major organs of zebrafish by 12 weeks with high-cholesterol (HC) and galactose (Gal) supplementation. At week 12, the HC control and HC+Gal control groups showed 96% and 92% survivability, respectively, while co-supplementation of the 0.5% BWA and 1.0% BWA groups exhibited 96% and 100% survivability. However, co-supplementation of the 0.5% CoQ10 and 1.0% CoQ10 groups revealed the lowest survivability, around 92% and 89%, respectively. The 0.5% BWA and 1.0% BWA groups showed 21% (p < 0.001) and 41% (p < 0.001), respectively, lower total cholesterol (TC) than the HC+Gal control, while the 1.0% CoQ10 group showed only 15% lower TC than the control. Interestingly, the 0.5% BWA and 1.0% BWA groups showed 22% (p < 0.001) and 38% (p < 0.001), respectively, lower triglyceride (TG) than the HC+Gal control. However, both the 0.5% CoQ10 and 1.0% CoQ10 groups showed similar TG levels as the control, suggesting that CoQ10 supplementation had no effect on lowering serum TG. The 1.0% BWA group showed the highest plasma HDL-C and HDL-C/TC (%) up to 3.2-fold and 5.5-fold, respectively, higher than those of the HC+Gal control, while the 1.0% CoQ10 group showed 2.4-fold and 2.8-fold higher plasma HDL-C and HDL-C/TC (%), respectively, than the control. The plasma aspartate transaminase (AST) and alanine transaminase (ALT) levels were lowest in the 1.0% BWA group, 51% and 72%, respectively, lower than HC+Gal control, suggesting the lowest extent of hepatic damage. In hepatic tissue, neutrophil infiltration and interleukin (IL)-6 production were the lowest in the 1.0% BWA group, around 67% and 85%, respectively, lower than the HC+Gal control. Fatty liver change, cellular apoptosis, and cell senescence in hepatic tissue were remarkably lowered in the 1.0% BWA group, while the CoQ10 group showed much less effect than the BWA group. In kidney, ovary, and testis tissue, the 1.0% BWA group showed the lowest production of reactive oxygen species, the extent of cellular senescence, and cellular apoptosis with the healthiest cell morphology. In conclusion, supplementation of BWA remarkably protected the liver, kidney, ovary, and testis from oxidative damage by cholesterol and galactose consumption, with the least serum AST and ALT levels, inflammatory parameters, and senescence markers.

The Effect of Local Papaverine Use in an Experimental High-Risk Colonic Anastomosis Model: Reduced Inflammatory Findings and Less Necrosis.

Objectives: To assess the impact of topical papaverine administration in complete and incomplete colonic anastomosis, by examining bursting pressure, hydroxyproline concentration, collagen content, inflammation levels, inflammatory cell infiltration, neoangiogenesis, and necrosis grades. Methods: We performed an experimental study on rats, in which they were divided into the following 4 groups of 16 subjects each. Group 1 [complete anastomosis (CA) without papaverine (CA -P) group], Group 2 [CA with papaverine (CA +P) group], Group 3 [incomplete anastomosis (ICA) without papaverine (ICA -P) group], and Group 4 [ICA with papaverine (ICA +P) group]. Results: The lymphocyte infiltration score of the ICA +P3 (day 3) group was significantly higher compared to the ICA -P3 group (p = 0.018). The median Ehrlich-Hunt score (p = 0.012), inflammation score (p = 0.026), and neutrophil infiltration score (p = 0.041) of the CA +P7 (day 7) group were significantly lower than the corresponding data of the CA -P7 group. Additionally, the necrosis score of the ICA +P7 group was significantly lower than that of the ICA -P7 group (p = 0.014). Conclusions: Data from the current study reveal that, although topical papaverine seems to suppress inflammation in anastomosis tissue and reduce necrosis at 7 days, definite conclusions regarding its impact on anastomotic leak cannot be drawn without further studies investigating anastomotic wound healing and anastomotic leak, preferably with both shorter- and longer-term evaluations.

Biodistribution and toxic potential of silver nanoparticles when introduced to the female rat reproductive tract

The prevalence of ionic silver and silver nanomaterials in hygiene products has been increasing due to their antimicrobial activity. While numerous studies have examined the effects of nanosilver in laboratory settings, there is a limited understanding of its impact on reproductive tissues, as well as its biodistribution and toxicity upon intra-vaginal exposure. If ionic or nanosilver enters adjacent and internal tissues via intra-vaginal exposure, the overuse of hygiene products containing silver may potentially threaten woman's health. This study investigated the effects of intra-vaginal silver exposure in Female Fischer 344 rats to single and multiple doses of a commercial product containing silver, along with standard nanosilver materials. Custom tampons were developed to simulate practical usage scenarios. The analysis of tissue biodistribution revealed that epithelial penetration and redistribution of silver was observed with most administered silver eliminated in feces (8–44 %), and secondary tissues containing 1–18 % of the dose, predominantly localized in the reproductive tract. In a subsequent toxicity study, vaginal histopathology indicated a cellular inflammatory reaction (neutrophil infiltration) associated with the presence of foreign silver material upon a single administration. Interestingly, no noticeable difference in histopathology incidence was observed upon multiple exposures to silver compared to the control group. Clinical chemistry and hematology analyses following acute exposure to silver nanomaterials showed no significant abnormalities. Overall, acute vaginal exposure to silver nanomaterials and ionic silver resulted in limited silver persistence, local tissue reactivity, epithelial penetration of silver resulting in accumulation in distant organs, and elimination primarily through feces. In vitro data suggested potential alterations in normal vaginal flora. Long-term studies are still lacking in this area.

Blockade of the CCR3 receptor reduces neutrophil recruitment to the lung during acute inflammation

Abstract Neutrophils represent one of the host's first lines of defense against invading pathogens. However, an aberrant activation can cause damage to the host. In the case of respiratory infections with viral or bacterial pathogens, one of the most common complications is the development of acute respiratory distress syndrome (ARDS), in which neutrophil infiltration into the lung is a hallmark. Neutrophils gain expression of chemokine receptors under inflammatory conditions, and their activation can amplify the neutrophil responses. Earlier studies showed that neutrophils recruited to the lung mucosa during bacterial infection upregulate expression of CCR3 and ex vivo stimulation of CCR3 results in an increased neutrophil activation. Therefore, the modulation of effector functions or migration of neutrophils to target sites through chemokine receptors constitutes an opportunity for pharmacological intervention. We aimed to determine whether the blockade of the CCR3 using the specific antagonist SB-328437 reduces neutrophil recruitment and inflammation in the lung in the LPS-induced lung injury model and influenza infection in mice. We found that neutrophils acquire CCR3 expression in the lung alveolar space. The intraperitoneal administration of SB-328437 reduced neutrophil recruitment to the lung alveolar space and reduced tissue damage in both the LPS-induced lung injury model and influenza infection. Moreover, treatment with SB-328437 reduced the percentage of neutrophils producing TNFα and neutrophil activation in the alveolar space. Together, these data suggest that CCR3 blockade might be a pharmacological strategy to prevent the aberrant neutrophil activation that results detrimental for the host but preserves sufficient effector response to control the pathogen.

Fei-yan-qing-hua decoction exerts an anti-inflammatory role during influenza by inhibiting the infiltration of macrophages and neutrophils through NF-κB and p38 MAPK pathways

Ethnopharmacological relevanceFei-Yan-Qing-Hua decoction (FYQHD) is an empirical formula that has shown clinical success in treating community-acquired pneumonia (CAP) for two decades. Influenza viral infection is a significant trigger for severe pneumonia, yet the role of FYQHD in treating influenza remains unclear. Aim of the studyThis study aimed to assess the potential efficacy of FYQHD in treating influenza viral infection and to elucidate its underlying mechanisms. Materials and methodsThe protective effects of FYQHD against influenza were evaluated through survival assessments and pathological analyses. Transcriptomic analysis was performed to identify the genes and pathways influenced by FYQHD in influenza. The anti-inflammatory effects and molecular mechanisms of FYQHD were studied in macrophages stimulated by Toll-like receptor (TLR) 7 ligation in vitro. The key constituents of FYQHD absorbed in mouse sera were identified using untargeted metabolomics, and the anti-inflammatory activity of some of these compounds in macrophages was evaluated using ELISA. ResultsOur findings demonstrate that FYQHD enhances survival and reduces lung damage in PR8-infected mice, primarily through its anti-inflammatory properties. Lung indexes and organ damage were significantly lower in the PR8 + OSV + FYQHD group compared to the PR8 + OSV group, indicating a potential complementary therapeutic effect of FYQHD and OSV in treating influenza. FYQHD effectively reduced chemokine expression, thereby decreasing the chemotaxis and infiltration of inflammatory monocytes/macrophages and neutrophils in the lungs. The anti-inflammatory effects of FYQHD in macrophages were achieved through the inhibition of NF-κB activation and p38 phosphorylation. The key constituents of FYQHD absorbed in mouse sera were identified, with some, such as wogonin, luteolin, kaempferol, and isorhamnetin, showing anti-inflammatory effects in primary macrophages. ConclusionFYQHD demonstrates protective efficacy against influenza and shows promise as an adjuvant therapeutic agent, particularly when used in combination with antiviral drugs like OSV. The potent anti-inflammatory components within FYQHD provide a basis for further exploration in drug research and development aimed at combating influenza.

Corynoline alleviates hepatic ischemia-reperfusion injury by inhibiting NLRP3 inflammasome activation through enhancing Nrf2/HO-1 signaling.

Corynoline has displayed pharmacological effects in reducing oxidative stress and inflammatory responses in many disorders. However, its effects on hepatic ischemia-reperfusion (I/R) injury remain unclear. This study aimed to investigate the protective effects of corynoline against hepatic I/R injury and the underlying mechanisms. Rat models with hepatic I/R injury and BRL-3A cell models with hypoxia/reoxygenation (H/R) insult were constructed. Models were pretreated with corynoline and/or other inhibitors for functional and mechanistic examination. Corynoline pretreatment effectively mitigated hepatic I/R injury verified by reduced serum transaminase levels, improved histological damage scores, and decreased apoptosis rates. Additionally, corynoline pretreatment significantly inhibited I/R-triggered oxidative stress and inflammatory responses, as indicated by enhanced mitochondrial function, reduced levels of ROS and MDA, reduced neutrophil infiltration and suppressed proinflammatory cytokine release. In vitro experiments further showed that corynoline pretreatment increased cellular viability, decreased LDH activity, reduced cellular apoptosis, and inhibited oxidative stress and inflammatory injury in H/R-induced BRL-3A cells. Mechanistically, corynoline significantly increased Nrf2 nuclear translocation and expression levels of its target gene, HO-1. It also blocked NLRP3 inflammasome activation both in vivo and in vitro. Furthermore, pretreatment with Nrf2 inhibitor ML-385 counteracted the protective effect of corynoline on hepatic I/R injury. Ultimately, in vitro studies revealed that the NLRP3 activator nigericin could also nullified the protective effects of corynoline in BRL-3A cells, but had minimal impact on Nrf2 nuclear translocation. Corynoline can exert protective effects against hepatic I/R injury by inhibiting oxidative stress, inflammatory responses, and apoptosis. These effects may be associated with inhibiting ROS-induced NLRP3 inflammasome activation by enhancing Nrf2/HO-1 signaling. These data provide new understanding about the mechanism of corynoline action, suggesting it is a potential drug applied for the treatment and prevention of hepatic I/R injury.

Analyses of single-cell and bulk RNA sequencing combined with machine learning reveal the expression patterns of disrupted mitophagy in schizophrenia.

Mitochondrial dysfunction is an important factor in the pathogenesis of schizophrenia. However, the relationship between mitophagy and schizophrenia remains to be elucidated. Single-cell RNA sequencing datasets of peripheral blood and brain organoids from SCZ patients and healthy controls were retrieved. Mitophagy-related genes that were differentially expressed between the two groups were screened. The diagnostic model based on key mitophagy genes was constructed using two machine learning methods, and the relationship between mitophagy and immune cells was analyzed. Single-cell RNA sequencing data of brain organoids was used to calculate the mitophagy score (Mitoscore). We found 7 key mitophagy genes to construct a diagnostic model. The mitophagy genes were related to the infiltration of neutrophils, activated dendritic cells, resting NK cells, regulatory T cells, resting memory T cells, and CD8 T cells. In addition, we identified 12 cell clusters based on the Mitoscore, and the most abundant neurons were further divided into three subgroups. Results at the single-cell level showed that Mitohigh_Neuron established a novel interaction with endothelial cells via SPP1 signaling pathway, suggesting their distinct roles in SCZ pathogenesis. We identified a mitophagy signature for schizophrenia that provides new insights into disease pathogenesis and new possibilities for its diagnosis and treatment.

Aconitate decarboxylase 1 mediates the acute airway inflammatory response to environmental exposures.

Environmental lipopolysaccharide (LPS) and microbial component-enriched organic dusts cause significant lung disease. These environmental exposures induce the recruitment and activation of distinct lung monocyte/macrophage subpopulations involved in disease pathogenesis. Aconitate decarboxylase 1 (Acod1) was one of the most upregulated genes following LPS (vs. saline) exposure of murine whole lungs with transcriptomic profiling of sorted lung monocyte/macrophage subpopulations also highlighting its significance. Given monocyte/macrophage activation can be tightly linked to metabolism, the objective of these studies was to determine the role of the immunometabolic regulator ACOD1 in environmental exposure-induced lung inflammation. Wild-type (WT) mice were intratracheally (i.t.) instilled with 10 μg of LPS or saline. Whole lungs were profiled using bulk RNA sequencing or sorted to isolate monocyte/macrophage subpopulations. Sorted subpopulations were then characterized transcriptomically using a NanoString innate immunity multiplex array 48 h post-exposure. Next, WT and Acod1-/- mice were instilled with LPS, 25% organic dust extract (ODE), or saline, whereupon serum, bronchoalveolar lavage fluid (BALF), and lung tissues were collected. BALF metabolites of the tricarboxylic acid (TCA) cycle were quantified by mass spectrometry. Cytokines/chemokines and tissue remodeling mediators were quantitated by ELISA. Lung immune cells were characterized by flow cytometry. Invasive lung function testing was performed 3 h post-LPS with WT and Acod1-/- mice. Acod1-/- mice treated with LPS demonstrated decreased BALF levels of itaconate, TCA cycle reprogramming, decreased BALF neutrophils, increased lung CD4+ T cells, decreased BALF and lung levels of TNF-α, and decreased BALF CXCL1 compared to WT animals. In comparison, Acod1-/- mice treated with ODE demonstrated decreased serum pentraxin-2, BALF levels of itaconate, lung total cell, neutrophil, monocyte, and B-cell infiltrates with decreased BALF levels of TNF-α and IL-6 and decreased lung CXCL1 vs. WT animals. Mediators of tissue remodeling (TIMP1, MMP-8, MMP-9) were also decreased in the LPS-exposed Acod1-/- mice, with MMP-9 also reduced in ODE-exposed Acod1-/- mice. Lung function assessments demonstrated a blunted response to LPS-induced airway hyperresponsiveness in Acod1-/- animals. Acod1 is robustly upregulated in the lungs following LPS exposure and encodes a key immunometabolic regulator. ACOD1 mediates the proinflammatory response to acute inhaled environmental LPS and organic dust exposure-induced lung inflammation.

Licochalcone A Ameliorates Aspergillus fumigatus Keratitis by Reducing Fungal Load and Activating the Nrf2/HO-1 Signaling Pathway.

Fungal keratitis (FK) is a blinding corneal infectious disease. The prognosis is frequently unfavorable due to fungal invasion and an excessive host inflammatory response. Licochalcone A (Lico A) exhibits a broad spectrum of pharmacological activities, encompassing antifungal, anti-inflammatory, antioxidation, and antitumor properties. However, the role of Lico A has not yet been studied in FK. In this study, we discovered that Lico A could disrupt Aspergillus fumigatus (A. fumigatus) biofilms, inhibit fungal growth and adhesion to host cells, induce alterations of hyphal morphology, and impair the cell membrane and cell wall integrity and mitochondrial structure of A. fumigatus. Lico A can alleviate the severity of FK in mice, reduce neutrophil infiltration and fungal load, and significantly decrease the pro-inflammatory cytokines in mouse corneas infected with A. fumigatus. In vitro, we also demonstrated that Lico A increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) around the nucleus in human corneal epithelial cells (HCECs) stimulated with A. fumigatus. We verified that the anti-inflammatory effect of Lico A is associated with the activation of the Nrf2/HO-1 axis. These results indicated that Lico A could provide a protective role in A. fumigatus keratitis through its anti-inflammatory and antifungal activities.

Abstract B041: Fibroblast STAT3 Signaling in Pancreatic Cancer: Implications for Immunotherapy and Tumor Microenvironment Modulation

Abstract Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer distinguished by a dense stromal microenvironment. The current investigation delves into the fibroblast-specific STAT3 signaling in the PDAC tumor microenvironment (TME) and its effects on immune cell infiltration and extracellular matrix (ECM) modulation. An association was identified between heightened levels of phosphorylated STAT3 (pSTAT3) in tumor-associated fibroblasts (CAFs) and a more unfavorable prognosis, particularly among male patients. Comparative analysis of gene expression patterns in normal fibroblasts and those deficient in STAT3, extracted from mouse models of pancreatic cancer, unveiled distinct gene expression profiles related to the inflammatory signaling pathway (IL6, ADM, CXCL11, CD80, VEGFA, TGFB1, STC1, STC2). Utilizing ChIP-Seq analysis with an anti-pSTAT3 antibody, it was confirmed that STAT3 binds to the regulatory regions of these genes, supporting its regulatory role in the inflammatory signaling pathway. Moreover, the absence of STAT3 in CAFs resulted in a decline in M2 macrophages and an upsurge in M1 macrophages within the TME, indicating a potential function of STAT3 in influencing macrophage polarization. Noteworthy observations also revealed that STAT3 signaling in CAFs impacts ECM remodeling, as illustrated by reduced collagen deposition. Furthermore, the deficiency of STAT3 in CAFs led to a notable reduction in the quantity of neutrophils within the TME in our mouse model. Additionally, a plausible involvement of STAT3 in neutrophil recruitment and activation through the CXCL1/CXCR2 axis was indicated. Alterations in the infiltration of neutrophils and macrophages due to the absence of STAT3 could profoundly influence the immune response against PDAC. The modified composition of ECM following STAT3 deletion might also impact the infiltration and functioning of immune cells. These outcomes underscore the significance of STAT3 signaling in CAFs as a promising therapeutic target in PDAC, offering potential for modulating the tumor microenvironment, augmenting anti-tumor immunity, and advancing patient outcomes. Citation Format: Samaneh Saberi, Cameron Bumbleburg, Caroline Everett, Julia E Lefler, Victoria Jordan, Lu Han, Sudarshana Sharma, Michael C. Ostrowski. Fibroblast STAT3 Signaling in Pancreatic Cancer: Implications for Immunotherapy and Tumor Microenvironment Modulation [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B041.

Abstract A051: Innate immune cell dynamics and pancreatic tumor progression in alcoholic pancreatitis

Abstract Introduction: Persistent inflammation due to alcoholic chronic pancreatitis (ACP) is associated with pancreatic ductal adenocarcinoma (PDAC). Myeloid cell infiltration within the pancreas, particularly with oncogenic mutant KrasG12D/+ (*Kras), is crucial for driving PDAC carcinogenesis. Our previous work demonstrated that hyperactivation of cyclic AMP response element binding protein (CREB) accelerates ADM/PanIN progression with heightened fibroinflammation. However, the association between CREB in precursor neoplastic lesions and innate myeloid cells remains unclear. Methods: We established an ACP mouse model using an alcohol diet along with prolonged caerulein administration in Ptf1aCreERTM/+; LSL-KrasG12D/+ (KC), and CREB deleted [Crebfl/fl in KC (KCC-/-)] mice. Single-cell RNA sequencing (scRNA-seq) of the mouse pancreas, multiparametric immunophenotyping of tumor-infiltrating myeloid cells and chromatin immunoprecipitation (ChIP-seq) with CREB pulldown were performed. Cytokine arrays and qPCR studies followed co-culture assays using mouse neutrophils (J774M) and macrophages (RAW 264.7) with epithelial cell lines harboring *Kras with in vitro ACP induction were conducted. Results: ACP induction in KC mice led to increased infiltration of neutrophils and alternatively activated macrophages with the pancreas. Conversely, Creb-deleted mice exhibited significantly reduced myeloid cell infiltration despite ACP induction. ChIP-Seq and qPCR identified CREB-regulated chemokines and immunomodulators as mediators of myeloid cell trafficking. Co-culture of mouse neutrophils and macrophages with KC-ACP conditioned media significantly increased IL-1 receptor antagonist (Il-1ra) expression and secretion. Single-cell transcriptomic analysis revealed heightened Il1rn mRNA levels in neutrophils and macrophages in KC-ACP when compared with KC pancreatic tumors. Creb-deleted PDAC models showed strong downregulation of Il1rn in macrophages, confirming CREB’s role in modulating myeloid cell interactions via epithelial cell signaling. Conclusions: Our findings highlight that CREB activation in epithelial cells under ACP conditions facilitates crosstalk with myeloid cells, promoting IL-1ra upregulation in neutrophils and macrophages. This CREB-driven regulation of IL-1ra in myeloid cells contributes to inflammation-associated tumorigenesis. Targeting this axis may offer a novel therapeutic approach to curb pancreatic cancer progression. Citation Format: Siddharth Mehra, Sudhakar Jinka, Varun Krishnamoorthy, Supriya Srinivasan, Anna Bianchi, Andrew Adams, Haleh Amirian, Manan Patel, Jashodeep Datta, Nipun Merchant, Nagaraj Nagathihalli. Innate immune cell dynamics and pancreatic tumor progression in alcoholic pancreatitis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A051.

Aloin alleviates corneal injury in alkali burn via inhibiting neutrophil extracellular traps and promoting Nrf2.

Ocular chemical burns are a leading cause of blindness. The cornea is injured by alkali-induced oxidative disturbances and an inflammatory response. The aim of this study was to evaluate the protective effects of aloin, an antioxidant, and anti-inflammatory compound, on corneal alkali burn. Mice eyes were injured by NaOH and subsequently treated with aloin eye drop and intraperitoneal injection. Pathological characteristics of the eyes were examined, and corneal samples were collected for further analysis. Aloin diminished neutrophil infiltration and the production of proinflammatory cytokines. Aloin also attenuated apoptosis in human corneal epithelial cells (HCEs) by reducing oxidative stress through the activation of the Nrf2 pathway. Additionally, aloin suppressed the formation of neutrophil extracellular traps (NETs) and inhibited their deposition on the cornea. Moreover, aloin mitigated alkali-induced apoptosis in HCEs caused by NETs. These findings suggest that aloin has potential as an antioxidant and anti-inflammatory compound for treating corneal alkali burn by inhibiting NETs formation and promoting Nrf2.

Disruption of the PGE2 synthesis / response pathway restrains atherogenesis in programmed cell death-1 (Pd-1) deficient hyperlipidemic mice.

Immune checkpoint inhibitors (ICIs) that target programmed cell death 1 (PD-1) have revolutionized cancer treatment by enabling the restoration of suppressed T-cell cytotoxic responses. However, resistance to single-agent ICIs still limits their clinical utility. Combinatorial strategies enhance the antitumor effects, but may also enhance the risk of immune related adverse effects of ICIs. Prostaglandin (PG) E2, formed by the sequential action of the cyclooxygenase (COX) and microsomal PGE synthase (mPGES-1) enzymes, acting via its E prostanoid (EP) receptors, EPr2 and EPr4, promotes lymphocyte exhaustion, revealing an additional target for ICIs. Thus, COX inhibitors and EPr4 antagonists are currently being combined with ICIs potentially to enhance antitumor efficacy in clinical trials. However, given the cardiovascular (CV) toxicity of COX inhibitors, such combinations may increase the risk particularly of CV AEs. Here, we compared the impact of distinct approaches to disruption of the PGE2 synthesis /response pathway- global or myeloid cell specific depletion of mPges-1 or global depletion of Epr4- on the accelerated atherogenesis in Pd-1 deficient hyperlipidemic (Ldlr KO) mice. All strategies restrained the atherogenesis. While depletion of mPGES-1 suppresses PGE2 biosynthesis, reflected by its major urinary metabolite, PGE2 biosynthesis was increased in mice lacking EPr4, consistent with enhanced expression of aortic Cox-1 and mPges-1. Deletions of mPges-1 and Epr4 differed in their effects on immune cell populations in atherosclerotic plaques; the former reduced neutrophil infiltration, while the latter restrained macrophages and increased the infiltration of T-cells. Consistent with these findings, chemotaxis by bone-marrow derived macrophages from Epr4 KO mice as impaired. in Epr4 depletion also resulted in extramedullary lymphoid hematopoiesis and inhibition of lipoprotein lipase activity (LPL) with coincident spelenomegaly, leukocytosis and dyslipidemia. Targeting either mPGES-1 or EPr4 may restrain lymphocyte exhaustion while mitigating CV irAEs consequent to PD-1 blockade.

The Effect of Tissue Inhibitor of Metalloproteinases on Scar Formation after Spinal Cord Injury.

Spinal cord injury (SCI) often results in permanent loss of motor and sensory function. After SCI, the blood-spinal cord barrier (BSCB) is disrupted, causing the infiltration of neutrophils and macrophages, which secrete several kinds of cytokines, as well as matrix metalloproteinases (MMPs). MMPs are proteases capable of degrading various extracellular matrix (ECM) proteins, as well as many non-matrix substrates. The tissue inhibitor of MMPs (TIMP)-1 is significantly upregulated post-SCI and operates via MMP-dependent and MMP-independent pathways. Through the MMP-dependent pathway, TIMP-1 directly reduces inflammation and destruction of the ECM by binding and blocking the catalytic domains of MMPs. Thus, TIMP-1 helps preserve the BSCB and reduces immune cell infiltration. The MMP-independent pathway involves TIMP-1's cytokine-like functions, in which it binds specific TIMP surface receptors. Through receptor binding, TIMP-1 can stimulate the proliferation of several types of cells, including keratinocytes, aortic smooth muscle cells, skin epithelial cells, corneal epithelial cells, and astrocytes. TIMP-1 induces astrocyte proliferation, modulates microglia activation, and increases myelination and neurite extension in the central nervous system (CNS). In addition, TIMP-1 also regulates apoptosis and promotes cell survival through direct signaling. This review provides a comprehensive assessment of TIMP-1, specifically regarding its contribution to inflammation, ECM remodeling, and scar formation after SCI.

The angiotensin-(1-7)/MasR axis improves pneumonia caused by Pseudomonas aeruginosa: Extending the therapeutic window for antibiotic therapy.

Pseudomonas aeruginosa is a frequent cause of antimicrobial-resistant hospital-acquired pneumonia, especially in critically ill patients. Inflammation triggered by P. aeruginosa infection is necessary for bacterial clearance but must be spatially and temporally regulated to prevent further tissue damage and bacterial dissemination. Emerging data have shed light on the pro-resolving actions of angiotensin-(1-7) [Ang-(1-7)] signaling through the G protein-coupled receptor Mas (MasR) during infections. Herein, we investigated the role of the Ang-(1-7)/Mas axis in pneumonia caused by P. aeruginosa by using genetic and pharmacological approach and found that Mas receptor-deficient animals developed a more severe form of pneumonia showing higher neutrophilic infiltration into the airways, bacterial load, cytokines, and chemokines production and more severe pulmonary damage. Conversely, treatment of pseudomonas-infected mice with Ang-(1-7) was able to decrease neutrophilic infiltration in airways and lungs, local and systemic levels of pro-inflammatory cytokines and chemokines, and increase the efferocytosis rates, mitigating lung damage/dysfunction caused by infection. Notably, the therapeutic association of Ang-(1-7) with antibiotics improved the survival rates of mice subjected to lethal inoculum of P. aeruginosa, extending the therapeutic window for imipenem. Mechanistically, Ang-(1-7) increased phagocytosis of bacteria by neutrophils and macrophages to accelerate pathogen clearance. Altogether, harnessing the Ang-(1-7) pathway during infection is a potential strategy for the development of host-directed therapies to promote mechanisms of resistance and resilience to pneumonia.

Identification of the shared gene MXD3 signatures and biological mechanism in patients with hip pain and prostate cancer.

Prostate cancer (PRAD) is recognized as having a significant effect on systemic illnesses. This study examined possible immune cells, metabolic pathways, and genes that may explain the interaction between PRAD and hip pain. We used information retrieved from the Cancer Genome Atlas and the Gene Expression Omnibus databases. To find common genes, we utilized differential expression analysis and weighted gene co-expression network analysis. The genes that were shared were subjected to pathway enrichment studies using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes. Additionally, hub genes were analyzed using LASSO regression, and a receiver operating characteristic curve was generated based on the screening outcomes. The genes for the nodes were chosen in a protein-protein interaction network that was built. Single-sample gene-set enrichment analysis was performed to identify the differentially expressed genes. Immunohistochemistry staining confirmed hub gene expression, and single-sample gene-set enrichment analysis assessed immune cell infiltration. We concluded by comparing MAX dimerization protein 3 (MXD3) and MAX interactor 1 (MXI1) expression in tumor tissues using Uniform Manifold Approximation and Projection and violin plots in the Tumor lmmune Single-cell Hub database. After analyzing the intersection of the differentially expressed genes and weighted gene co-expression network analysis-significant module genes, we determined that MXD3 was the best shared diagnostic biomarker for PRAD and hip pain. One potential predictor of PRAD development was the MXI1 node gene, which was found in the protein-protein interaction network. The analyses revealed that MXD3 had a relatively positive correlation with neutrophil and T-helper cell infiltration levels, whereas MXI1 had a negative correlation with mast and Tgd cell levels. Tumors had lower levels of MXI1 expression and higher levels of MXD3 expression compared to normal tissues. Endothelial cells, induced pluripotent stem cells, and smooth muscle cells were all found to express MXI1. This is the first study to investigate the close genetic link between hip pain and PRAD using bioinformatics technologies. The 2 most significant genes involved in crosstalk between PRAD and hip pain were MXD3 and MXI1. The immunological responses triggered by T cells, mast cells, and neutrophils may be crucial in the relationship between PRAD and hip pain.

C-Kit Immunohistochemical Expression as a Complementary Method to Assess Mast Cell Density in Helicobacter Pylori-mediated Gastritis.

Chronic gastritis is a group of conditions commonly characterized by stomach lining inflammation. The study aims to investigate the clinical and pathological aspects that play a role in its development. Additionally, the study examines the use of CD117 as an immunohistochemistry marker in evaluating mast cell density (MCD). This retrospective, cross-sectional study was conducted in Iraqi Kurdistan with a sample size of 380 patients. Patient data included gastritis type, neutrophil infiltration severity, mononuclear cell infiltration within the lamina propria, intestinal metaplasia, and glandular atrophy, which were categorized and given a score. The CD117 level was identified using an anti-human rabbit polyclonal antibody. A statistically significant association was revealed between Helicobacter pylori-mediated gastritis and non-specific gastritis with age, activity, H. pylori and MCD, dysplasia, and malignancy. Meanwhile, no association was found with gender, inflammatory infiltrate, intestinal metaplasia, and glandular atrophy. C-Kit exhibited a marked increase in MCD in patients with H. pylori-mediated gastritis, intestinal metaplasia, atrophy, and gastric carcinoma. However, a significant decrease in MCD was observed on repeating endoscopy evaluations for patients after treatment. Regions that exhibit severe inflammation, metaplasia, atrophy, and carcinoma demonstrated an increase in MCD with H. pylori-mediated gastritis. A detailed investigation in clinical practice to screen early diagnosis and treatment needs to be performed in high H. pylori prevalence.

SKAP1 Expression in Cancer Cells Enhances Colon Tumor Growth and Impairs Cytotoxic Immunity by Promoting Neutrophil Extracellular Trap Formation via the NFATc1/CXCL8 Axis.

The mechanisms underlying the development and progression of colon cancer are not fully understood. Herein, Src kinase associated phosphoprotein 1 (SKAP1), an immune cell adaptor, is identified as a novel colon cancer-related gene. SKAP1 expression is significantly increased in colon cancer cells. High SKAP1 levels are independently predictive of poor survival in patients with colon cancer. Notably, SKAP1 expression in colon cancer cells exerted a significant tumor-promoting effect in vivo rather than in vitro. Screening of tumor-infiltrating immune cells revealed the involvement of neutrophils in SKAP1-induced colon tumor promotion. Enhanced formation of neutrophil extracellular traps (NETs) is found to be a key downstream event that contributed to the pro-tumor role of SKAP1. In colon cancer cells, SKAP1 increased the expression of C-X-C motif chemokine ligand 8 (CXCL8) via nuclear factor of activated T cells c1 (NFATc1). The blockade of CXCL8 or NFATc1 largely attenuated neutrophil infiltration, NET formation, and tumor promotion induced by SKAP1. Furthermore, inhibiting SKAP1-induced NET significantly enhanced the antitumor efficiency of adoptive natural killer cell therapy in colon tumor models. In conclusion, SKAP1 significantly promotes colon cancer growth via the cancer cell/neutrophil NFATc1/CXCL8/NET axis, suggesting that SKAP1 is a potential target for colon cancer therapy.

Parvovirus B19 Infection Is Associated with the Formation of Neutrophil Extracellular Traps and Thrombosis: A Possible Linkage of the VP1 Unique Region.

Neutrophil extracellular traps (NETs) formation, namely NETosis, is implicated in antiphospholipid syndrome (APS)-related thrombosis in various autoimmune disorders such as systemic lupus erythematosus (SLE) and APS. Human parvovirus B19 (B19V) infection is closely associated with SLE and APS and causes various clinical manifestations such as blood disorders, joint pain, fever, pregnancy complications, and thrombosis. Additionally, B19V may trigger the production of autoantibodies, including those against nuclear and phospholipid components. Thus, exploring the connection between B19V, NETosis, and thrombosis is highly relevant. An in vitro NETosis model using differentiated HL-60 neutrophil-like cells (dHL-60) was employed to investigate the effect of B19V-VP1u IgG on NETs formation. A venous stenosis mouse model was used to test how B19V-VP1u IgG-mediated NETs affect thrombosis in vivo. The NETosis was observed in the dHL-60 cells treated with rabbit anti-B19V-VP1u IgG and was inhibited in the presence of either 8-Br-cAMP or CGS216800 but not GSK484. Significantly elevated reactive oxygen species (ROS), myeloperoxidase (MPO), and citrullinated histone (Cit-H3) levels were detected in the dHL60 treated with phorbol myristate acetate (PMA), human aPLs IgG and rabbit anti-B19V-VP1u IgG, respectively. Accordingly, a significantly larger thrombus was observed in a venous stenosis-induced thrombosis mouse model treated with PMA, human aPLs IgG, rabbit anti-B19V-VP1u IgG, and human anti-B19V-VP1u IgG, respectively, along with significantly increased amounts of Cit-H3-, MPO- and CRAMP-positive infiltrated neutrophils in the thrombin sections. This research highlights that anti-B19V-VP1u antibodies may enhance the formation of NETosis and thrombosis and implies that managing and treating B19V infection could lower the risk of thrombosis.