OBJECTIVE: Binge drinking (i.e., consuming enough alcohol to achieve a blood ethanol concentration of 80 mg/dL, approximately 4-5 drinks within 2 hours), particularly in early adolescence, can promote progressive increases in alcohol drinking and alcohol-related problems that develop into compulsive use in the chronic relapsing disease, alcohol use disorder (AUD). Over the past decade, neuroimmune signaling has been discovered to contribute to alcohol-induced changes in drinking, mood, and neurodegeneration. This review presents a mechanistic hypothesis supporting high mobility group box protein 1 (HMGB1) and Toll-like receptor (TLR) signaling as key elements of alcohol-induced neuroimmune signaling across glia and neurons, which shifts gene transcription and synapses, altering neuronal networks that contribute to the development of AUD. This hypothesis may help guide further research on prevention and treatment.
METHODS: The authors used the search terms \"HMGB1 protein,\" \"alcohol,\" and \"brain\" across PubMed, Scopus, and Embase to find articles published between 1991 and 2023.
UNASSIGNED: The database search found 54 references in PubMed, 47 in Scopus, and 105 in Embase. A total of about 100 articles were included.
CONCLUSIONS: In the brain, immune signaling molecules play a role in normal development that differs from their functions in inflammation and the immune response, although cellular receptors and signaling are shared. In adults, pro-inflammatory signals have emerged as contributing to brain adaptation in stress, depression, AUD, and neurodegenerative diseases. HMGB1, a cytokine-like signaling protein released from activated cells, including neurons, is hypothesized to activate pro-inflammatory signals through TLRs that contribute to adaptations to binge and chronic heavy drinking. HMGB1 alone and in heteromers with other molecules activates TLRs and other immune receptors that spread signaling across neurons and glia. Both blood and brain levels of HMGB1 increase with ethanol exposure. In rats, an adolescent intermittent ethanol (AIE) binge drinking model persistently increases brain HMGB1 and its receptors; alters microglia, forebrain cholinergic neurons, and neuronal networks; and increases alcohol drinking and anxiety while disrupting cognition. Studies of human postmortem AUD brain have found elevated levels of HMGB1 and TLRs. These signals reduce cholinergic neurons, whereas microglia, the brain\'s immune cells, are activated by binge drinking. Microglia regulate synapses through complement proteins that can change networks affected by AIE that increase drinking, contributing to risks for AUD. Anti-inflammatory drugs, exercise, cholinesterase inhibitors, and histone deacetylase epigenetic inhibitors prevent and reverse the AIE-induced pathology. Further, HMGB1 antagonists and other anti-inflammatory treatments may provide new therapies for alcohol misuse and AUD. Collectively, these findings suggest that restoring the innate immune signaling balance is central to recovering from alcohol-related pathology.

BACKGROUND: Porcine beta defensin 2 (pBD2) is one of the porcine beta defensins that has antibacterial activity, and plays an important role in the immunomodulatory activity that protects cells from pathogens. It has been reported that pBD2 plays their immunomodulatory functions related to the TLR4-NF-κB signal pathways. However, it is not completely clear how pBD2 reduces the inflammatory response caused by pathogens.
RESULTS: In this study, the effect of pBD2 on the expression of genes in the TLRs signaling pathway was investigated after IPEC-J2 cells were challenged with E. coli. The results showed that pBD2 decreased the expression of IL-8 induced by E. coli (P < 0.05), and pBD2 significantly decreased the expression of TLR4, TLR5 and TLR7 (P < 0.05), as well as the key downstream genes p38 and JNK which activated by E. coli (P < 0.05). In addition, pBD2 inhibited the p-p65, p-p38 and p-JNK which were up-regulated by E. coli.
CONCLUSIONS: pBD2 could reduce the inflammatory response induced by E. coli perhaps by inhibiting the TLRs-TAK1-NF-κB/MAPK signaling pathway which was activated by E. coli in IPEC-J2 cells. Our study further reveals the immunomodulatory activity of recombinant pBD2 against E. coli, and provides insights into the molecular mechanisms that protect cells from E. coli infection.

BACKGROUND: Toll-like receptors (TLRs) are a family of fundamental pattern recognition receptors in the innate immune system, constituting the first line of defense against endogenous and exogenous antigens. The gut microbiota, a collection of commensal microorganisms in the intestine, is a major source of exogenous antigens. The components and metabolites of the gut microbiota interact with specific TLRs to contribute to whole-body immune and metabolic homeostasis.
OBJECTIVE: This review aims to summarize the interaction between the gut microbiota and TLR signaling pathways and to enumerate the role of microbiota dysbiosis-induced TLR signaling pathways in obesity, inflammatory bowel disease (IBD), and colorectal cancer (CRC).
RESULTS: Through the recognition of TLRs, the microbiota facilitates the development of both the innate and adaptive immune systems, while the immune system monitors dynamic changes in the commensal bacteria to maintain the balance of the host-microorganism symbiosis. Dysbiosis of the gut microbiota can induce a cascade of inflammatory and metabolic responses mediated by TLR signaling pathways, potentially resulting in various metabolic and inflammatory diseases.
CONCLUSIONS: Understanding the crosstalk between TLRs and the gut microbiota contributes to potential therapeutic applications in related diseases, offering new avenues for treatment strategies in conditions like obesity, IBD, and CRC.

Rheumatic heart disease (RHD) caused by group A streptococcus infection is one of the most important reasons of cardiovascular morbidity and mortality in low- and middle-income countries. Aberrant host immune response modulated by polymorphisms in inflammatory response genes plays an important role in RHD pathogenesis. This study aimed to determine risk-associated polymorphic variants in inflammatory response genes in Caucasian RHD patients. A total of 251 Caucasian RHD patients and 300 healthy donors were recruited for this study, and 27 polymorphic sites in 12 genes (TLR1, TLR2, TLR4, TLR6, IL1B, IL6R, IL6, IL10, IL12RB1, IL12B, TNF and CRP) were analyzed using allele-specific PCR. It was demonstrated that the polymorphic variants rs1800871 and rs1800872 in the IL10 gene, rs 1130864, rs3093077 and rs1205 in the CRP gene, rs375947 in the IL12RB1 gene, rs 5743551 and rs5743611 in the TLR1 gene, and rs3775073 in the TLR6 gene can modify RHD risk in a gender- and age-dependent manner. The obtained results can be used to determine the personalized risk of RHD in healthy donors during medical examination or screening, as well as to develop appropriate early prevention strategies targeting RHD in the risk groups.

BACKGROUND: AT-MSCs display great immunoregulatory features, making them potential candidates for cell-based therapy. This study aimed to evaluate the \"RBC lysis buffer\" isolation protocol and immunological profiling of the so-obtained AT-MSCs.
METHODS: We established an immune-comparative screening of AT-MSCs throughout in vitro cell expansion (PM, P1, P2, P3, P4) and inflammatory priming regarding the expression of 28 cell-surface markers, 6 cytokines/chemokines, and 10 TLR patterns.
RESULTS: AT-MSCs were highly expandable and sensitive to microenvironment challenges, hereby showing plasticity in distinct expression profiles. Both cell expansion and inflammation differentially modulated the expression profile of CD34, HLA-DR, CD40, CD62L, CD200 and CD155, CD252, CD54, CD58, CD106, CD274 and CD112. Inflammation resulted in a significant increase in the expression of the cytokines IL-6, IL-8, IL-1β, IL-1Ra, CCL5, and TNFα. Depending on the culture conditions, the expression of the TLR pattern was distinctively altered with TLR1-4, TLR7, and TLR10 being increased, whereas TLR6 was downregulated. Protein network and functional enrichment analysis showed that several trophic and immune responses are likely linked to these immunological changes.
CONCLUSIONS: AT-MSCs may sense and actively respond to tissue challenges by modulating distinct and specific pathways to create an appropriate immuno-reparative environment. These mechanisms need to be further characterized to identify and assess a molecular target that can enhance or impede the therapeutic ability of AT-MSCs, which therefore will help improve the quality, safety, and efficacy of the therapeutic strategy.

Toll-like receptors (TLRs) are critical components to stimulate immune responses against various infections. Recently, TLR agonists have emerged as a promising way to activate anti-tumor immunity. L-pampo, a TLR1/2 and TLR3 agonist, induces humoral and cellular immune responses and also causes cancer cell death. In this study, we investigated the L-pampo-induced signals and delineated their interactions with molecular signaling pathways using RNA-seq in immune cells and colon and prostate cancer cells. We first constructed a template network with differentially expressed genes and influential genes from network propagation using the weighted gene co-expression network analysis. Next, we obtained perturbed modules using the above method and extracted core submodules from them by conducting Walktrap. Finally, we reconstructed the subnetworks of major molecular signals utilizing a shortest path-finding algorithm, TOPAS. Our analysis suggests that TLR signaling activated by L-pampo is transmitted to oxidative phosphorylation (OXPHOS) with reactive oxygen species (ROS) through PI3K-AKT and JAK-STAT only in immune and prostate cancer cells that highly express TLRs. This signal flow may further sensitize prostate cancer to L-pampo due to its high basal expression level of OXPHOS and ROS. Our computational approaches can be applied for inferring underlying molecular mechanisms from complex gene expression profiles.

Influenza virus possesses an RNA genome of single-stranded, negative-sensed, and segmented configuration. Influenza virus causes an acute respiratory disease, commonly known as the \"flu\" in humans. In some individuals, flu can lead to pneumonia and acute respiratory distress syndrome. Influenza A virus (IAV) is the most significant because it causes recurring seasonal epidemics, occasional pandemics, and zoonotic outbreaks in human populations, globally. The host innate immune response to IAV infection plays a critical role in sensing, preventing, and clearing the infection as well as in flu disease pathology. Host cells sense IAV infection through multiple receptors and mechanisms, which culminate in the induction of a concerted innate antiviral response and the creation of an antiviral state, which inhibits and clears the infection from host cells. However, IAV antagonizes and escapes many steps of the innate antiviral response by different mechanisms. Herein, we review those host and viral mechanisms. This review covers most aspects of the host innate immune response, i.e., (1) the sensing of incoming virus particles, (2) the activation of downstream innate antiviral signaling pathways, (3) the expression of interferon-stimulated genes, (4) and viral antagonism and escape.

BACKGROUND: The meticulous selection of appropriate vaccine adjuvants is crucial for optimizing immune responses. Traditionally, pemphigus vulgaris (PV), an autoimmune disorder, has been modelled using complete Freund\'s adjuvant (CFA). In this study, we aimed to discern potential variations in immune responses elicited by Toll-like receptor (TLR) ligands as compared to CFA.
METHODS: A comprehensive investigation was conducted, comparing the effects of these adjuvants in conjunction with ovalbumin or desmoglein-3. Flow cytometry was employed to analyse distinct cell subsets, while enzyme-linked immunosorbent assay quantified antigen-specific antibodies and cytokine levels. Histological examination of harvested skin tissues and transcriptome analysis of skin lesions were performed to identify differentially expressed genes.
RESULTS: TLR ligands demonstrated efficacy in inducing PV-like symptoms in wild-type mice, in contrast to CFA. This underscored the substantial impact of the adjuvant on self-antigen tolerance. Furthermore, we proposed an enhanced method for establishing a PV model through adoptive transfer, substituting CFA with TLR ligands. Our results revealed that in contrast to the perception that CFA being the most potent immunopotentiator reported, CFA promoted regulatory T cells (Treg), follicular regulatory T cells and IL-10-producing neutrophils, whereas TLR ligands downregulated CCL17 and IL-10. This suggested potential implications for the recruitment and activation of Treg subsets. While B cell and CD8+ T cell responses exhibited similarity, CFA induced less activation in dendritic cell subsets. A novel mouse model of PV and systemic comparison of immunostimulatory effects of adjuvants were provided by this study.
CONCLUSIONS: The systematic comparison of CFA and TLR ligands shed light on the distinctive properties of these adjuvants, presenting innovative mouse models for the investigation of pemphigus. This study significantly contributes to adjuvant research and advances our understanding of PV pathogenesis.
UNASSIGNED: Immunization with desmoglein 3 and Toll-like receptor (TLR) ligands effectively induces pemphigus symptoms in wild-type mice, whereas complete Freund\'s adjuvant (CFA) fails. TLR ligands heightened the autoreactivity of donor cells in the adoptive transfer pemphigus model. CFA promoted regulatory T cells and IL-10-producing neutrophils, whereas TLR ligands downregulated CCL17 and IL-10, leading to more effective immune responses.

UNASSIGNED: Dengue is one of the important vector-borne viral diseases affecting humans with diverse manifestations. Toll-like receptors (TLR) are pattern recognition receptors and play an important role in innate immunity against microbes. TLR3 plays a critical role in controlling the innate immune response mediated by flaviviruses such as dengue.
UNASSIGNED: We attempted to study the susceptibility of single nucleotide polymorphism of the TLR3 gene in dengue encephalitis (DE) patients and determine the association in terms of genotype, allele, and haplotype distribution along with the clinical outcome.
UNASSIGNED: It was a case-controlled observational study in a tertiary care hospital.
UNASSIGNED: We investigated the single nucleotide polymorphism in the TLR3 Leu412Phe gene using real-time polymerase chain reaction in 29 cases of DE and compared them with equal number of age- and sex-matched dengue patients without neurological features.
UNASSIGNED: The genotype and allele frequencies were compared using a two-sided Chi-square or Fisher\'s exact test.
UNASSIGNED: The findings revealed that the genotypic distribution of TLR3 Leu412Phe polymorphism for the mutant genotype Phe/Phe (TT) demonstrated increased association of DE (31.03% vs 6.8%, P 0.019, odds ratio 6.075, 95% confidence interval 1.181-31.245). However, the number of heterozygous (H) genotype (Leu/Phe-CT) and mutant Phe allele (T) did not show any statistically significant association. TLR3 gene polymorphism did not show any correlation with mortality outcome at 1 month.
UNASSIGNED: The presence of mutant TLR3 Leu412Phe polymorphism may confer the propensity to have DE in patients with dengue infection in the Indian population. TLR3 polymorphism did not affect mortality outcome at 1 month.

Natural killer (NK) cells play a crucial role in innate immunity, particularly in combating infections and tumors. However, in hematological cancers, NK cells often exhibit impaired functions. Therefore, it is very important to activate its endosomal Toll-like receptors (TLRs) as a potential strategy to restore its antitumor activity. We stimulated NK cells from the peripheral blood mononuclear cells from children with acute lymphoblastic leukemia and NK cells isolated, and the NK cells were stimulated with specific TLR ligands (Poly I:C, Imiquimod, R848, and ODN2006) and we evaluated changes in IFN-γ, CD107a, NKG2D, NKp44 expression, Granzyme B secretion, cytokine/chemokine release, and cytotoxic activity. Results revealed that Poly I:C and Imiquimod enhanced the activation of both immunoregulatory and cytotoxic NK cells, increasing IFN-γ, CD107a, NKG2D, and NKp44 expression. R848 activated immunoregulatory NK cells, while ODN2006 boosted CD107a, NKp44, NKG2D, and IFN-γ secretion in cytotoxic NK cells. R848 also increased the secretion of seven cytokines/chemokines. Importantly, R848 and ODN 2006 significantly improved cytotoxicity against leukemic cells. Overall, TLR stimulation enhances NK cell activation, suggesting TLR8 (R848) and TLR9 (ODN 2006) ligands as promising candidates for antitumor immunotherapy.