Elevations in interleukin-8 levels in individuals with alcohol use disorder and clinical insomnia symptoms.

BACKGROUND: Insomnia commonly co-occurs with alcohol use disorder (AUD) and predicts poorer outcomes for those with AUD. Insomnia and AUD are individually associated with increases in systemic inflammation. Insomnia and inflammation both serve as risk factors for relapse in AUD. However, little is known about the relationship between insomnia and systemic inflammation in individuals with AUD. Therefore, the present study examined the relationship between the severity of insomnia symptoms and plasma levels of inflammatory cytokines in a sample of treatment-seeking individuals with an AUD. METHODS: This secondary analysis included 101 (61M/40F) individuals with an AUD. Participants were categorized into groups based on their scores on the Insomnia Severity Index: no insomnia (n = 47), subthreshold insomnia (n = 37), and clinical insomnia (n = 17). Participants provided blood samples to measure plasma levels of four peripheral markers of inflammation (IL-6, IL-8, TNF-α, and CRP). Inflammatory marker levels were compared between groups. Interactive effects of sex and AUD severity were examined. RESULTS: There was a significant main effect of insomnia group on log IL-8 levels (F = 6.52, p = 0.002), such that individuals with AUD and clinical insomnia had higher log IL-8 levels compared to both the no insomnia and subthreshold insomnia groups (ps ≤ 0.05). Sex and AUD severity interacted with this relationship, such that men with clinical insomnia and AUD and individuals with severe AUD had higher log IL-8 levels. There were no significant effects of insomnia on IL-6, TNF-α, or CRP levels. CONCLUSION: The present study identified a specific elevation in IL-8 levels in individuals with an AUD and clinical insomnia that was not identified in other markers of peripheral inflammation (IL-6, TNF-α, CRP). Sex and AUD severity interacted with insomnia symptoms, indicating that those with clinical insomnia and severe AUD or male sex may be the most vulnerable to the inflammatory consequences associated with AUD and clinical insomnia symptoms.

Immunological Biomarkers in Autism Spectrum Disorder: The Role of TNF-Alpha and Dependent Trends in Serum IL-6 and CXCL8.

BACKGROUND: Autism spectrum disorder (ASD) has seen a rise in prevalence, and the immune system's role in brain development is increasingly recognized. This study investigates the relationship between immune dysregulation and ASD by examining serum concentrations of interleukin 6 (IL-6), interleukin 8 (CXCL8), and tumor necrosis factor alpha (TNF-alpha) in children. METHODS: Serum samples from 45 children with ASD and 30 controls, aged 2 to 12 years, were analyzed using electrochemiluminescence, chemiluminescent microparticle immunoassay, and chemiluminescent immunoassay. ASD symptoms were assessed using the Autism Spectrum Rating Scale (ASRS) and Social Communication Questionnaire (SCQ). RESULTS: No significant correlation was observed between CXCL8 levels and ASD. IL-6 levels showed a trend toward elevation in boys with ASD. TNF-alpha levels were significantly higher in children with ASD under 5 years compared to older children and controls, though no correlation with symptom severity was found. CONCLUSIONS: TNF-alpha may be a potential biomarker for early ASD detection, especially in younger children. Further research on larger cohorts is needed to understand the role of immune dysregulation in ASD.

IL-8 promotes lens capsular residual cells migration by down-regulates expression of E-cadherin and ZO-1 via the CXCR1/2-NF-κB-RhoA signal pathway.

BACKGROUND: Posterior capsular opacification is a major complication following cataract surgery, marked by proliferation, migration, epithelial-mesenchymal transition, and fibrosis of residual epithelial cells. Various inflammatory cytokines are upregulated and contribute to the development of posterior capsular opacification. The effect of interleukin-8 on residual epithelial cells has not been fully determined. METHODS: Aqueous humor and anterior capsules samples were collected from cataract surgery. Capsular bags from rats and pigs were cultured in DMEM media. Protein and mRNA expressions were measured using immunoblot and qPCR. Cell migration was assessed using the transwell assay. RESULTS: Interleukin-8 is an early inflammatory factor secreted by residual lens epithelial cells. Migration of lens epithelial cells in aqueous humor positively correlates with interleukin-8 levels, and this effect is inhibited by the receptors of interleukin-8 CXCR1/2 blocker Reparaxin. The expression of tight-junction protein ZO-1 and cell-adhesion protein E-cadherin were down-regulated by administrating interleukin-8, and cell migration of both SRA01/04 cell line in vitro and capsular residual epithelial cells ex vivo were up-regulated via activating RhoA expression and RhoA/GTPase activity. The loss-of- function studies demonstrate that interleukin-8 binding to its receptor CXCR1/2 activates NF-κB/p65, which then turns on the RhoA's expression and RhoA/GTPase activity, and RhoA-modulated the downexpression of E-cadherin and ZO-1 and the increase of cell migration. CONCLUSIONS: The upregulation in interleukin-8 occurs early in posterior capsular opacification and contributes to down-regulating tight-junctions among epithelial cells and elevates cell migration via the CXCR1/2-NF-κB-RhoA signaling pathway. These demonstrated that interleukin-8 could be a potential target for preventing posterior capsular opacification.

Dynamin 2-mediated endocytosis of BLT1 is required for IL-8 production in HMC-1 cells induced by Trichomonas vaginalis-derived secretory products.

We previously reported that leukotriene B4 (LTB4) contained in Trichomonas vaginalis-derived secretory products (TvSP) play an essential role in interleukin-8 (IL-8) production in human mast cell line (HMC-1 cells) via LTB4 receptor (BLT)-mediated Nuclear Factor-kappa B (NF-кB) activation. Dynamin, a GTPase, has been known to be involved in endocytosis of receptors for signaling of production of cytokine or chemokines. In the present study, we investigated the role of dynamin-mediated BLT1 endocytosis in TvSP-induced IL-8 production. When HMC-1 cells were transfected with BLT1 or BLT2 siRNA, TvSP-induced IL-8 production was significantly inhibited compared with that in cells transfected with control siRNA. In addition, pretreatment of HMC-1 cells with a dynamin inhibitor (Dynasore) reduced IL-8 production induced by TvSP or LTB4. TvSP- or LTB4- induced phosphorylation of NF-кB was also attenuated by pretreatment with Dynasore. After exposing HMC-1 cells to TvSP or LTB4, BLT1 was translocated from the intracellular compartments to the plasma membrane within 30 min. At 60 min after stimulation with TvSP or LTB4, BLT1 remigrated from the cell surface to intracellular areas. Pretreatment of HMC-1 cells with dynamin-2 siRNA blocked internalization of BLT1 induced by TvSP or LTB4. Co-immunoprecipitation experiments revealed that dynamin-2 strongly interacted with BLT1 60 min after stimulation with TvSP or LTB4. These results suggest that T. vaginalis-secreted LTB4 induces IL-8 production in HMC-1 cells via dynamin 2-mediated endocytosis of BLT1 and phosphorylation of NF-кB.

CysLT receptor-mediated NOX2 activation is required for IL-8 production in HMC-1 cells induced by Trichomonas vaginalis-derived secretory products.

Trichomoniasis is caused by a sexually transmitted flagellate protozoan parasite Trichomonas vaginalis. T. vaginalis-derived secretory products (TvSP) contain lipid mediators such as leukotriene B4 (LTB4) and various cysteinyl leukotrienes (CysLTs) which included LTC4, LTD4, and LTE4. However, the signaling mechanisms by which T. vaginalis-induced CysLTs stimulate interleukin (IL)-8 production in human mast cells remain unclear. In this study, we investigated these mechanisms in human mast cells (HMC-1). Stimulation with TvSP resulted in increased intracellular reactive oxygen species (ROS) generation and NADPH oxidase 2 (NOX2) activation compared to unstimulated cells. Pre-treatment with NOX2 inhibitors such as diphenyleneiodonium chloride (DPI) or apocynin significantly reduced ROS production in TvSP-stimulated HMC-1 cells. Additionally, TvSP stimulation increased NOX2 protein expression and the translocation of p47phox from the cytosol to the membrane. Pretreatment of HMC-1 cells with PI3K or PKC inhibitors reduced TvSP-induced p47phox translocation and ROS generation. Furthermore, NOX2 inhibitors or NOX2 siRNA prevented CREB phosphorylation and IL-8 gene expression or protein secretion induced by TvSP. Pretreatment with a CysLTR antagonist significantly inhibited TvSP-induced ROS production, CREB phosphorylation, and IL-8 production. These results indicate that CysLT-mediated activation of NOX2 plays a crucial role in ROS-dependent IL-8 production in human mast cells stimulated by T. vaginalis-secreted CysLTs. These findings enhance our understanding of the inflammatory response in trichomoniasis and may inform the development of targeted therapies to mitigate this response.

PoIL8-L, a teleost interleukin-8 like, enhances leukocyte cellular vitality and host defense against bacterial infections in Japanese flounder (Paralichthys olivaceus).

Interleukin-8 (IL-8), a CXC chemokine, exerts pivotal effect on cell migration, inflammatory response, and immune regulation. In this study, we examined the immunological characteristics of an IL-8 like homologue (PoIL8-L) in Japanese flounder (Paralichthys olivaceus). PoIL8-L contains a conserved chemokine CXC domain and 105 amino acid residues. PoIL8-L expression in tissues was constitutive, and significantly regulated by V. havieri or E. tarda infection. In vitro, rPoIL8-L could bind to eight tested bacteria, exhibited bacteriostatic and bactericidal effects against certain bacteria, and could bind to the targeted bacterial Ⅳ pilin protein rPilA of E. tarda. Furthermore, rPoIL8-L could attach to peripheral blood leukocytes, and enhance their immune genes expression, respiratory burst, chemotaxis, proliferation, acid phosphatase activity, and phagocytic activity. Additionally, rPoIL8-L induce neutrophils to extrude neutrophil extracellular traps. In vivo, rPoIL8-L could promote host resistance to E. tarda infection. In summary, these findings provide fresh perspectives on the immunological antibacterial properties of IL-8 in teleost.

Anterior Chamber Flare as a Non-Invasive Assessment of Intraocular Immune Status and Ocular Complications in Proliferative Diabetic Retinopathy.

Proliferative diabetic retinopathy (PDR) is a vision-threatening complication of diabetes mellitus (DM). Anterior chamber (AC) flare and intraocular cytokines are potent biomarkers reflecting the intraocular immune status in PDR. This study aimed to elucidate the complex interrelationship between AC flare and intraocular cytokines in PDR eyes. A retrospective observational study was conducted on 19 PDR eyes of 19 patients with type 2 DM, and on 19 eyes of 19 patients with idiopathic macular hole or epiretinal membrane as controls. AC flare was measured before pars plana vitrectomy (PPV). Aqueous humor (AH) and vitreous fluid (VF) samples were collected at the time of PPV, and the quantities of 27 cytokines in both intraocular fluids were analyzed. In the PDR and control groups, Spearman's rank correlation analysis revealed a positive correlation between AC flare and IL-8 level in both AH and VF. Additionally, IL-8 levels in AH correlated positively with IL-8 levels in VF. In the PDR group, receiver operating characteristic curve analysis identified IL-8 level in AH as a significant predictor for both diabetic macular edema (DME) and vitreous hemorrhage (VH) complications. The cut-off values of IL-8 were established at ≥26.6 pg/mL for DME and ≥7.96 pg/mL for VH. Given the positive correlation between AC flare and AH IL-8 level, the present findings suggest that AC flare value may potentially be a non-invasive biomarker for predicting DME.

Correlation of sputum inflammatory markers with severity and blood inflammatory markers in bronchiectasis.

Background: As a disease characterized by chronic neutrophilic inflammation, various sputum biomarkers have been investigated in the association with the severity and prognosis of bronchiectasis. However, there is lack of data on the association between sputum interleukin-1beta (IL-1ß), interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) levels at clinical stable state and the clinical, spirometric and blood inflammatory parameters, as well as prognostic scores. The purpose of the study is to assess the association between sputum IL-1ß, IL-8 and TNF-α levels at clinical stable state and various clinical and laboratory parameters in bronchiectasis. Methods: A prospective study was conducted in a major regional hospital and tertiary respiratory referral centre in Hong Kong, including 44 Chinese patients with bronchiectasis. The correlation between stable state sputum IL-1ß, IL-8 and TNF-α levels with various clinical, laboratory and spirometric parameters in bronchiectasis, as well as FACED [forced expiratory volume in one second (FEV1), age, chronic colonisation by Pseudomonas aeruginosa, radiological extension and dyspnoea]/E-FACED (FACED plus exacerbations) scores were assessed. Results: Baseline sputum IL-1ß level was found to have significant moderate positive correlation with baseline blood high sensitivity C-reactive protein (hs-CRP) level with Pearson correlation coefficient (r) of 0.529 (P=0.001). Baseline sputum IL-8 level was found to have significant moderate positive correlation with baseline FACED and E-FACED score with r of 0.574 (P<0.001) and 0.539 (P<0.001) respectively. Baseline sputum TNF-α level was found to have significant moderate positive correlation with baseline FACED score with r of 0.520 (P<0.001). Conclusions: Sputum IL-1ß and, IL-8 and TNF-α levels were shown to have significant correlation with various clinical, laboratory and spirometry parameters in bronchiectasis, as well as more severe disease as measured by FACED and E-FACED scores.

Somatic cell count as an indicator of subclinical mastitis and increased inflammatory response in asymptomatic lactating women.

Subclinical mastitis is an asymptomatic inflammatory condition that can be difficult to define and diagnose. In the dairy industry, subclinical mastitis is diagnosed by milk somatic cell counts (SCCs) of ≥250,000 cells mL-1. In this pilot study, we assessed the efficacy of this index to identify human subclinical mastitis by comparing SCC levels with the inflammatory response [interleukin-8 (IL-8) levels] in 37 samples from asymptomatic and 10 clinical mastitis (CM) lactating women. The milk microbiota was determined by 16S rRNA gene sequencing. The SCC of CM samples ranged from 310,000 to 6,600,000 cells mL-1. However, 14 of 37 (37.8%) asymptomatic samples had high SCC (250,000-460,000 cells mL-1), indicating subclinical mastitis. SCC levels significantly (P < 0.001) and positively correlated with milk IL-8 levels reflecting the escalating inflammatory response across subclinical and clinical mastitis samples. Samples with an SCC of ≥250,000 cells mL-1 showed significant increases in IL-8 responses when compared with milk samples from healthy women. The milk microbiome of CM samples was dominated by streptococcal and staphylococcal species (89.9% combined median relative abundance). In contrast, the combined median streptococcal/staphylococcal relative levels were 75.4% and 66.3% in milks from asymptomatic (subclinical mastitis) and healthy groups, respectively. The Streptococcus genus was increased in samples with an SCC of ≥250,000, although this should be interpreted with caution. Thus, the index of ≥250,000 somatic cells mL-1 could be a reliable indicator of subclinical mastitis in humans and should aid future studies investigating the impact of subclinical mastitis on maternal health, breastfeeding behaviors, infant health, and development. IMPORTANCE: This pilot study suggests that SCC at a level of (greater than or equal to) 250,000 cells mL-1, as used in the dairy industry, is a suitable index to identify asymptomatic subclinical mastitis in lactating women since it reflects a significant increase in the inflammatory response compared to milk samples from healthy women. Using this index should aid studies into the short- and long-term consequences of subclinical mastitis for mother and infant.

Matrix Metalloproteinase 9 (MMP-9) and Interleukin-8 (IL-8) in Gingival Crevicular Fluid after Minimally Invasive Periodontal Surgery with or without Er:YAG and Nd:YAG Laser Application.

BACKGROUND: This study aimed to evaluate alterations in the concentrations of matrix metalloproteinase-9 (MMP-9) and interleukin-8 (IL-8) within gingival crevicular fluid (GCF) extracted from the intrabony periodontal defect site before and after minimally invasive regenerative surgery, with or without supplemental laser application. The surgical procedure was performed using the modified minimally invasive surgical technique (M-MIST). METHODS: Thirty-eight patients, each presenting with a single vertical defect, were randomly assigned to either the test (M-MIST + Er:YAG + Nd:YAG) or the control group (M-MIST). IL-8 and MMP-9 levels (primary outcomes of the study) were assessed prior to therapy, after 2 and 4 weeks, and 6 months following the surgical procedure by means of dedicated ELISA kits. RESULTS: Both procedures were clinically effective as evidenced by probing depth (PD) reduction and clinical attachment level (CAL) gain at the 6-month follow-up. No statistical differences were observed in the levels of MMP-9 and IL-8 between the groups at any time point assessed. The changes in the level of MMP-9 and IL-8 over time were not statistically significant in any group. IL-8 was positively correlated with MMP-9 in the control group throughout the study and in the test group 2 weeks and 6 months post-op. CONCLUSIONS: Within the limitations of this study, the additional application of Er:YAG + Nd:YAG lasers alongside the M-MIST procedure did not enhance the clinical and biochemical treatment outcomes compared to M-MIST alone.

Extracellular Vesicles Induce Nuclear Factor-κB Activation and Interleukin-8 Synthesis through miRNA-191-5p Contributing to Inflammatory Processes: Potential Implications in the Pathogenesis of Chronic Obstructive Pulmonary Disease.

Extracellular vesicles (EVs) play a pivotal role in a variety of physiologically relevant processes, including lung inflammation. Recent attention has been directed toward EV-derived microRNAs (miRNAs), such as miR-191-5p, particularly in the context of inflammation. Here, we investigated the impact of miR-191-5p-enriched EVs on the activation of NF-κB and the expression of molecules associated with inflammation such as interleukin-8 (IL-8). To this aim, cells of bronchial epithelial origin, 16HBE, were transfected with miR-191-5p mimic and inhibitor and subsequently subjected to stimulations to generate EVs. Then, bronchial epithelial cells were exposed to the obtained EVs to evaluate the activation of NF-κB and IL-8 levels. Additionally, we conducted a preliminary investigation to analyze the expression profiles of miR-191-5p in EVs isolated from the plasma of patients diagnosed with chronic obstructive pulmonary disease (COPD). Our initial findings revealed two significant observations. First, the exposure of bronchial epithelial cells to miR-191-5p-enriched EVs activated the NF-kB signaling and increased the synthesis of IL-8. Second, we discovered the presence of miR-191-5p in peripheral blood-derived EVs from COPD patients and noted a correlation between miR-191-5p levels and inflammatory and functional parameters. Collectively, these data corroborate and further expand the proinflammatory role of EVs, with a specific emphasis on miR-191-5p as a key cargo involved in this process. Consequently, we propose a model in which miR-191-5p, carried by EVs, plays a role in airway inflammation and may contribute to the pathogenesis of COPD.

Targeting IL-8 and Its Receptors in Prostate Cancer: Inflammation, Stress Response, and Treatment Resistance.

This review delves into the intricate roles of interleukin-8 (IL-8) and its receptors, CXCR1 and CXCR2, in prostate cancer (PCa), particularly in castration-resistant (CRPC) and metastatic CRPC (mCRPC). This review emphasizes the crucial role of the tumour microenvironment (TME) and inflammatory cytokines in promoting tumour progression and response to tumour cell targeting agents. IL-8, acting through C-X-C chemokine receptor type 1 (CXCR1) and type 2 (CXCR2), modulates multiple signalling pathways, enhancing the angiogenesis, proliferation, and migration of cancer cells. This review highlights the shift in PCa research focus from solely tumour cells to the non-cancer-cell components, including vascular endothelial cells, the extracellular matrix, immune cells, and the dynamic interactions within the TME. The immunosuppressive nature of the PCa TME significantly influences tumour progression and resistance to emerging therapies. Current treatment modalities, including androgen deprivation therapy and chemotherapeutics, encounter persistent resistance and are complicated by prostate cancer's notably "immune-cold" nature, which limits immune system response to the tumour. These challenges underscore the critical need for novel approaches that both overcome resistance and enhance immune engagement within the TME. The therapeutic potential of inhibiting IL-8 signalling is explored, with studies showing enhanced sensitivity of PCa cells to treatments, including radiation and androgen receptor inhibitors. Clinical trials, such as the ACE trial, demonstrate the efficacy of combining CXCR2 inhibitors with existing treatments, offering significant benefits, especially for patients with resistant PCa. This review also addresses the challenges in targeting cytokines and chemokines, noting the complexity of the TME and the need for precision in therapeutic targeting to avoid side effects and optimize outcomes.

Genetic Influences of Proinflammatory Cytokines on Pain Severity in Patients with Temporomandibular Disorders.

This case-control study investigated single nucleotide polymorphism (SNP) genotypes (CXC motif chemokine ligand 8 (CXCL8): rs2227306 and rs2227307 and tumor necrosis factor (TNF): rs1800629) in 85 patients with pain-related temporomandibular disorders (TMDp) and 85 controls to explore their associations with TMDp presence, pain intensity (low/high), and the presence of chronic arthralgia/myalgia. TMDp was diagnosed using a validated protocol, and polymorphisms were genotyped from buccal mucosa swabs using TaqMan assays. High pain intensity individuals had an increased risk for carrying minor allele "G" (rs2227307) and "T" (rs2227306) compared to controls (76% vs. 55.3%, p = 0.012; 72% vs. 54.1%, p = 0.030, respectively). Carriers of the minor allele "G" (rs2227307) were more prevalent in TMDp patients with arthralgia compared to controls (70.30% vs. 55.30%, p = 0.037). According to logistic regression, the most important predictors for high pain intensity were minor allele "G" of rs2227307 (OR 2.435, 95% CI 1.123-5.282), increasing age (OR 1.038, 95% CI 1.002-1.075), and female sex (OR 4.592, 95% CI 1.289-16.361). The explored gene polymorphisms were not significant risk factors for TMDp presence. These findings highlight the importance of genetic variations, particularly rs2227307, in understanding the diverse clinical manifestations of temporomandibular disorders.

Elevation of IL-8 secretion induced by PEDV infection via NF-κB signaling pathway.

Porcine epidemic diarrhea virus (PEDV) is associated with severe enteritis, which contributes to high mortality in piglets. The aim of this study was to describe molecular mechanisms associated with proinflammatory cytokine(s) production during PEDV infection. We showed that infection of porcine intestine epithelial cell clone J2 (IPEC-J2) with PEDV induces a gradual increase in interleukin 8 (IL-8) production at different time points, as well as infection of Vero E6 with PEDV. The secretion of IL-8 in these two cell lines infected with PEDV is related to the activation of NF-κB. Furthermore, the cells expressing PEDV M or E protein can induce the upregulation of IL-8. These findings suggest that the IL-8 production can be the initiator of inflammatory response by the host cells upon PEDV infection.

Autocrine IL-8 Contributes to Propionibacterium Acnes-induced Proliferation and Differentiation of HaCaT Cells via AKT/FOXO1/ Autophagy.

OBJECTIVE: Proprionibacterium acnes (P. acnes)-induced inflammatory responses, proliferation and differentiation of keratinocytes contribute to the progression of acne vulgaris (AV). P. acnes was found to enhance the production of interleukin-8 (IL-8) by keratinocytes. This study aimed to investigate the role of IL-8 in P. acnes-induced proliferation and differentiation of keratinocytes and the underlying mechanism. METHODS: The P. acnes-stimulated HaCaT cell (a human keratinocyte cell line) model was established. Western blotting and immunofluorescence were performed to detect the expression of the IL-8 receptors C-X-C motif chemokine receptor 1 (CXCR1) and C-X-C motif chemokine receptor 2 (CXCR2) on HaCaT cells. Cell counting kit-8 (CCK-8) assay, 5-ethynyl-20-deoxyuridine (EdU) assay and Western blotting were performed to examine the effects of IL-8/CXCR2 axis on the proliferation and differentiation of HaCaT cells treated with P. acnes, the IL-8 neutralizing antibody, the CXCR2 antagonist (SB225002), or the CXCR1/CXCR2 antagonist (G31P). Western blotting, nuclear and cytoplasmic separation, CCK-8 assay, and EdU assay were employed to determine the downstream pathway of CXCR2 after P. acnes-stimulated HaCaT cells were treated with the CXCR2 antagonist, the protein kinase B (AKT) antagonist (AZD5363), or the constitutively active forkhead box O1 (FOXO1) mutant. Finally, autophagy markers were measured in HaCaT cells following the transfection of the FOXO1 mutant or treatment with the autophagy inhibitor 3-methyladenine (3-MA). RESULTS: The expression levels of CXCR1 and CXCR2 were significantly increased on the membrane of HaCaT cells following P. acnes stimulation. The IL-8/CXCR2 axis predominantly promoted the proliferation and differentiation of P. acnes-induced HaCaT cells by activating AKT/FOXO1/autophagy signaling. In brief, IL-8 bound to its receptor CXCR2 on the membrane of keratinocytes to activate the AKT/FOXO1 axis. Subsequently, phosphorylated FOXO1 facilitated autophagy to promote the proliferation and differentiation of P. acnes-induced keratinocytes. CONCLUSION: This study demonstrated the novel autocrine effect of IL-8 on the proliferation and differentiation of P. acnes-induced keratinocytes, suggesting a potential therapeutic target for AV.

Activity and levels of TNF-α, IL-6 and IL-8 in saliva of children and young adults with dental caries: a systematic review and meta-analysis.

BACKGROUND: Cytokines play an important role in the immunopathogenesis of dental caries. A systematic review and meta-analysis was carried out with the following three objectives: 1)To deepen and discuss through a comprehensive analysis of the literature the effects of dental caries on the activity and levels of TNF-α, IL-6 and IL-8 in saliva of children and young adults, 2)To compare the levels of this cytokines in saliva of the exposure group (moderate-severe dental caries) with the control group (caries-free or mild dental caries), and 3)To determine whether the levels of these cytokines could be used as a complementary clinical diagnostic tool to assess the severity of dental caries. METHODS: The protocol followed PRISMA and Cochrane guidelines and was registered in the Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/MF74V . A digital search was performed in PubMed/MEDLINE, Cochrane, Scopus, and Google Schoolar databases from February 15th, 2012, to January 13th, 2024. The methodological validity of the selected studies was assessed using Joanna Briggs Institute (JBI) tool. A meta-analysis was performed using a random-effects model to evaluate the association between dental caries/health, and the concentration of TNF-α, IL-6 and IL-8. RESULTS: The search strategy provided a total of 126 articles, of which 15 investigations met the inclusion criteria. The total number of patients studied was 1,148, of which 743 represented the case/exposure group, and 405 represented the control group. The age of the patients ranged from 3 to 25 years. IL-6 was the most prevalent cytokine in the saliva of children and young adults with active dental caries. The meta-analysis revealed that there are significant differences between the levels of IL-6 and TNF-α in saliva of children with active dental caries compared to their control groups. CONCLUSIONS: The findings suggest that IL-6 and TNF-α levels may have potential as complementary biomarkers for assessing dental caries severity. However, further research is needed to validate these findings in larger and more diverse populations before clinical application.

The Diagnostic and Prognostic Role of Interleukin 6 and Interleukin 8 in Childhood Acute Gastroenteritis-A Review of the Literature.

Acute gastroenteritis in pediatric patients represents a major cause of morbidity and mortality in children. Interleukins 6 (IL-6) and 8 (IL-8) have been intensely studied in relation to various inflammatory conditions, including acute gastroenteritis, as they are activated in response to infection. This review aims to evaluate the ability of IL-6 and IL-8 to distinguish between bacterial and viral etiologies of acute gastroenteritis in children and to assess whether their levels correlate with the severity of this condition in light of currently available data. A scientific database search was performed to identify studies that investigated the role of IL-6 and IL-8 in acute gastroenteritis in the pediatric population. We identified nine studies that matched the review's objective. Both cytokines show increased values in acute gastroenteritis, but IL-6 levels are significantly higher in cases of bacterial infections. IL-8 levels do not present an increase to the same extent in cases of bacterial diarrhea in children but seem to be associated with the severity of the disease. The lack of sufficient research focusing on IL-6 and -8 as diagnostic, prognostic and severity biomarkers of acute gastroenteritis in children leaves room for further research on this topic, which must include larger cohort studies.

IL-8 Induces Neutrophil Extracellular Trap Formation in Severe Thermal Injury.

Neutrophil extracellular traps (NETs) have a dual role in the innate immune response to thermal injuries. NETs provide an early line of defence against infection. However, excessive NETosis can mediate the pathogenesis of immunothrombosis, disseminated intravascular coagulation (DIC) and multiple organ failure (MOF) in sepsis. Recent studies suggest that high interleukin-8 (IL-8) levels in intensive care unit (ICU) patients significantly contribute to excessive NET generation. This study aimed to determine whether IL-8 also mediates NET generation in patients with severe thermal injuries. IL-8 levels were measured in serum samples from thermally injured patients with ≥15% of the total body surface area (TBSA) and healthy controls (HC). Ex vivo NET generation was also investigated by treating isolated neutrophils with serum from thermal injured patients or normal serum with and without IL-8 and anti-IL-8 antibodies. IL-8 levels were significantly increased compared to HC on days 3 and 5 (p < 0.05) following thermal injury. IL-8 levels were also significantly increased at day 5 in septic versus non-septic patients (p < 0.001). IL-8 levels were also increased in patients who developed sepsis compared to HC at days 3, 5 and 7 (p < 0.001), day 10 (p < 0.05) and days 12 and 14 (p < 0.01). Serum containing either low, medium or high levels of IL-8 was shown to induce ex vivo NETosis in an IL-8-dependent manner. Furthermore, the inhibition of DNase activity in serum increased the NET-inducing activity of IL-8 in vitro by preventing NET degradation. IL-8 is a major contributor to NET formation in severe thermal injury and is increased in patients who develop sepsis. We confirmed that DNase is an important regulator of NET degradation but also a potential confounder within assays that measure serum-induced ex vivo NETosis.

Interleukin-8 in HepG2 cells: Enhancing antiviral proteins in uninfected cells but promoting HBV replication in infected cells.

In vitro studies have revealed that hepatitis B virus (HBV) infection upregulates interleukin-8 (IL-8), which enhances HBV replication. Clinically, elevated IL-8 levels in chronic HBV patients are associated with diminished therapeutic efficacy of interferon-α (IFN-α). Our study advances these findings by demonstrating that IL-8 promotes the expression of myxovirus resistance A (MxA) and protein kinase R (PKR) in HepG2 cells via the PI3K-AKT pathway. However, HBV-infected cells fail to exhibit IL-8-induced upregulation of MxA and PKR, likely due to HBV's upregulation of PP2A that inhibits the PI3K-AKT pathway. Notably, IL-8 targets the C/EBPα transcription factor, increasing HBV promoter activity and viral replication, which in turn partially suppresses the expression of MxA and PKR induced by IFN-α. Our findings uncover a mechanism by which HBV may evade immune responses, suggesting potential new strategies for immunotherapy against chronic HBV infection.

Prognostic impact of Interleukin-8 levels in lung cancer: A meta-analysis and a bioinformatic validation.

BACKGROUND: High interleukin-8 (IL-8) levels have been linked to poor prognosis in lung cancer, but conclusive data are lacking. MATERIALS AND METHODS: A comprehensive search was conducted on April 1st, 2023, from electronic databases, focusing on studies with IL-8 expression evaluations and the availability of hazard ratio (HR) and 95% confidence intervals (CI) for overall survival (OS), progression-free survival (PFS) and disease-free survival (DFS) or adequate data for their estimation. Then, we examined IL-8 and CXCR1 RNA-seq data from The Cancer Genome Atlas (TCGA) dataset, and we correlated these data with OS. RESULTS: Among 2655 produced records, 10 manuscripts involving both non-small cell lung cancer and small cell lung cancer, were included in the analysis. Two manuscripts and one study included two and three different cohorts, respectively, for a total of 14 cohorts of patients. Overall, 4 cohorts evaluated IL-8 levels in patients treated with chemotherapy, 3 cohorts immunotherapy, 2 cohorts surgical patients and 4 cohorts other treatments; 1 cohort was removed, as the type of treatments was lacking. The 12 cohorts included in the OS analysis revealed that patients with high IL-8 levels have a lower OS probability, as compared to patients with low IL-8 levels (HR=1.75, 95 % CI 1.36-2.26). No significant difference between patients with high and low IL-8 levels was observed in the 8 cohorts available for PFS analysis. Sensitivity analysis according to treatment revealed significant PFS and OS differences for patients treated with chemotherapy or immunotherapy. Analysis of RNA-seq data from TCGA, confirmed the correlation between high IL-8 and CXCR1 expression and worse OS in patients with resected lung cancer. CONCLUSION: To the best of our knowledge, this study represents the first meta-analysis demonstrating a negative prognostic impact of high IL-8 level in lung cancer, particularly in patients treated with chemotherapy and/or immunotherapy.