Altered Immune Response Research Articles

Single-cell landscape of functionally cured chronic hepatitis B patients reveals activation of innate and altered CD4-CTL-driven adaptive immunity

Hepatitis B surface antigen (HBsAg) loss or functional cure (FC) is considered the optimal therapeutic outcome for patients with chronic hepatitis B (CHB). However, the immune-pathological biomarkers and underlying mechanisms of FC remain unclear. In this study we comprehensively interrogate disease-associated cell states identified within intrahepatic tissue and matched PBMCs (peripheral blood mononuclear cells) from patients with CHB or after FC, at the resolution of single cells, to provide novel insights into putative mechanisms underlying FC. We combined single-cell transcriptomics (single-cell RNA sequencing) with multiparametric flow cytometry-based immune phenotyping, and multiplexed immunofluorescence to elucidate the immunopathological cell states associated with CHB vs. FC. We found that the intrahepatic environment in CHB and FC displays specific cell identities and molecular signatures that are distinct from those found in matched PBMCs. FC is associated with the emergence of an altered adaptive immune response marked by CD4 cytotoxic T lymphocytes, and an activated innate response represented by liver-resident natural killer cells, specific Kupffer cell subtypes and marginated neutrophils. Surprisingly, we found MHC class II-expressing hepatocytes in patients achieving FC, as well as low but persistent levels of covalently closed circular DNA and pregenomic RNA, which may play an important role in FC. Our study provides conceptually novel insights into the immuno-pathological control of HBV cure, and opens exciting new avenues for clinical management, biomarker discovery and therapeutic development. We believe that the discoveries from this study, as it relates to the activation of an innate and altered immune response that may facilitate sustained, low-grade inflammation, may have broader implications in the resolution of chronic viral hepatitis. This study dissects the immuno-pathological cell states associated with functionally cured chronic hepatitis B (defined by the loss of HBV surface antigen or HBsAg). We identified the sustained presence of very low viral load, accessory antigen-presenting hepatocytes, adaptive-memory-like natural killer cells, and the emergence of helper CD4 T cells with cytotoxic or effector-like signatures associated with functional cure, suggesting previously unsuspected alterations in the adaptive immune response, as well as a key role for the innate immune response in achieving or maintaining functional cure. Overall, the insights generated from this study may provide new avenues for the development of alternative therapies as well as patient surveillance for better clinical management of chronic hepatitis B.

Implications of IFNγ SNP rs2069705 in primary Sjögren's syndrome: transcriptional activation and B cell infiltration.

Primary Sjögren's syndrome (pSS) is characterized by its autoimmune nature. This study investigates the role of the IFNγ SNP rs2069705 in modulating the susceptibility to pSS. Differential expression of IFNγ and BAFF was analyzed using the GEO database's mRNA microarray GSE84844. Genotyping of the IFNγ SNP rs2069705 was conducted via the dbSNP website. The JASPAR tool was used for predicting transcription factor bindings. Techniques such as dual-luciferase reporter assays, Chromatin immunoprecipitation, and analysis of a pSS mouse model were applied to study gene and protein interactions. A notable increase in the mutation frequency of IFNγ SNP rs2069705 was observed in MNCs from the exocrine glands of pSS mouse models. Bioinformatics analysis revealed elevated levels of IFNγ and BAFF in pSS samples. The model exhibited an increase in both CD20+ B cells and cells expressing IFNγ and BAFF. Knocking down IFNγ resulted in lowered BAFF expression and less lymphocyte infiltration, with BAFF overexpression reversing this suppression. Activation of the Janus kinase (JAK)/STAT1 pathway was found to enhance transcription in the BAFF promoter region, highlighting IFNγ's involvement in pSS. In addition, rs2069705 was shown to boost IFNγ transcription by promoting interaction between its promoter and STAT4. SNP rs2069705 in the IFNγ gene emerges as a pivotal element in pSS susceptibility, primarily by augmenting IFNγ transcription, activating the JAK/STAT1 pathway, and leading to B-lymphocyte infiltration in the exocrine glands.NEW & NOTEWORTHY The research employed a combination of bioinformatics analysis, genotyping, and experimental models, providing a multifaceted approach to understanding the complex interactions in pSS. We have uncovered that the rs2069705 SNP significantly affects the transcription of IFNγ, leading to altered immune responses and B-lymphocyte activity in pSS.

Characterization of Antimicrobial Poly(Lactic Acid)- and Polyurethane-Based Materials Enduring Closed-Loop Recycling with Applications in Space.

Recent studies have shown that astronauts experience altered immune response behavior during spaceflight, resulting in heightened susceptibility to illness. Resources and resupply shuttles will become scarcer with longer duration spaceflight, limiting access to potentially necessary medical treatment and facilities. Thus, there is a need for preventative health countermeasures that can exploit in situ resource utilization technologies during spaceflight, such as additive manufacturing (i.e., 3D printing). The purpose of the current study was to test and validate recyclable antimicrobial materials compatible with additive manufacturing. Antimicrobial poly(lactic acid)- and polyurethane-based materials compatible with 3D printing were assessed for antimicrobial, mechanical, and chemical characteristics before and after one closed-loop recycling cycle. Our results show high biocidal efficacy (>90%) of both poly(lactic acid) and polyurethane materials while retaining efficacy post recycling, except for recycled-state polyurethane which dropped from 98.91% to 0% efficacy post 1-year accelerated aging. Significant differences in tensile and compression characteristics were observed post recycling, although no significant changes to functional chemical groups were found. Proof-of-concept medical devices developed show the potential for the on-demand manufacturing and recyclability of typically single-use medical devices using antimicrobial materials that could serve as preventative health countermeasures for immunocompromised populations, such as astronauts during spaceflight.

Serological surveillance reveals a high exposure to SARS-CoV-2 and altered immune response among COVID-19 unvaccinated Cameroonian individuals.

Surveillance of COVID-19/SARS-CoV-2 dynamics is crucial to understanding natural history and providing insights into the population's exposure risk and specific susceptibilities. This study investigated the seroprevalence of SARS-CoV-2 antibodies, its predictors, and immunological status among unvaccinated patients in Cameroon. A multicentre cross-sectional study was conducted between January and September 2022 in the town of Douala. Patients were consecutively recruited, and data of interest were collected using a questionnaire. Blood samples were collected to determine Immunoglobin titres (IgM and IgG), interferon gamma (IFN- γ) and interleukin-6 (IL-6) by ELISA, and CD4+ cells by flow cytometry. A total of 342 patients aged 41.5 ± 13.9 years were included. Most participants (75.8%) were asymptomatic. The overall crude prevalence of IgM and IgG was 49.1% and 88.9%, respectively. After adjustment, the seroprevalence values were 51% for IgM and 93% for IgM. Ageusia and anosmia have displayed the highest positive predictive values (90.9% and 82.4%) and specificity (98.9% and 98.3%). The predictors of IgM seropositivity were being diabetic (aOR = 0.23, p = 0.01), frequently seeking healthcare (aOR = 1.97, p = 0.03), and diagnosed with ageusia (aOR = 20.63, p = 0.005), whereas those of IgG seropositivity included health facility (aOR = 0.15, p = 0.01), age of 40-50 years (aOR = 8.78, p = 0.01), married (aOR = 0.21, p = 0.02), fever (aOR = 0.08, p = 0.01), and ageusia (aOR = 0.08, p = 0.01). CD4+, IFN-γ, and IL-6 were impaired in seropositive individuals, with a confounding role of socio-demographic factors or comorbidities. Although the WHO declared the end of COVID-19 as a public health emergency, the findings of this study indicate the need for continuous surveillance to adequately control the disease in Cameroon.

Cytotoxic Lymphocyte-Monocyte Complex Reflects the Dynamics of Coronavirus Disease 2019 Systemic Immune Response.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes a variety of clinical manifestations, many of which originate from altered immune responses, either locally or systemically. Immune cell cross-talk occurs mainly in lymphoid organs. However, systemic cell interaction specific to coronavirus disease 2019 has not been well characterized. Here, by employing single-cell RNA sequencing and imaging flow cytometry analysis, we unraveled, in peripheral blood, a heterogeneous group of cell complexes formed by the adherence of CD14+ monocytes to different cytotoxic lymphocytes, including SARS-CoV-2-specific CD8+ T cells, γδ T cells, and natural killer T cells. These lymphocytes attached to CD14+ monocytes that showed enhanced inflammasome activation and pyroptosis-induced cell death in progression stage; in contrast, in the convalescent phase, CD14+ monocytes with elevated antigen presentation potential were targeted by cytotoxic lymphocytes, thereby restricting the excessive immune activation. Collectively, our study reports previously unrecognized cell-cell interplay in the SARS-CoV-2-specific immune response, providing new insight into the intricacy of dynamic immune cell interaction representing antiviral defense.

Abstract TP286: Spatial Transcriptome Profile of Stem Cell-Mediated Recovery in Stroke-Injured Rat Brains

Introduction: Intraparenchymal stem cell transplantation shows therapeutic promise for chronic ischemic stroke patients. Our previous phase 1/2a trial revealed a transient T2-FLAIR (fluid-attenuated inversion recovery) MRI signal in the premotor cortex following intraparenchymal stem cell transplantation, the size of which positively correlated with the extent of clinical recovery. We sought to elucidate the underlying molecular mechanisms in this FLAIR region that may facilitate post-stroke recovery using spatial transcriptomic profiling in stroke-injured rat brains. Methods: Adult male SD rats underwent 30 min transient middle cerebral artery occlusion followed at 1 month by transplantation of human ES-derived neural stem cells (NR1) or buffer into the ipsilesional striatum. Whisker paw test and various MRI sequences (T2, FLAIR, DWI) were performed at multiple time points. The Visium platform (10X Genomics) was used for unbiased spatial transcriptome analysis in two stem-cell and two vehicle-treated brains at the peak of FLAIR. Results: We successfully replicated transplant-induced FLAIR after chronic stroke in rats and found a positive correlation between FLAIR and improved neurological outcomes. Visium identified specific gene clusters for the stroke injury, transplant/needle-track, stem cell graft, and the cortical ‘FLAIR’ region. The latter consisted of a central core containing the gene signature of the needle track and blood, and a wider region around this core which encompassed the FLAIR lesion seen by MRI. This wider FLAIR region displayed a predominantly microglia/inflammation-associated signature and was best characterized by the upregulation of apoptosis-associated genes. Pathway analysis of the differentially-expressed genes in the FLAIR cluster revealed a significant representation of immune cell responses (e.g. phagocytosis, immune cell migration, cytokine signaling), as well as ER stress mechanisms. Conclusion: This pilot study provides initial evidence that altered immune responses in the stem cell transplant-induced FLAIR region may promote recovery after chronic stroke. Further research on the role of microglia/neuroinflammation is needed to understand the mechanisms of stem cell-mediated brain repair.

Association between single nucleotide polymorphisms of interleukin-35 genes and atopic dermatitis.

The pathogenesis of atopic dermatitis (AD) involves complex interactions between environmental factors, the skin microbiome, epidermal barrier defects, and altered immune responses that develop on a not fully understood specific genetic background. We aimed to evaluate the contribution of single nucleotide polymorphisms (SNPs) in the IL-35 genes (IL-12A and EBI3) towards AD susceptibility and clinical characteristics of AD in the Polish population. Two SNPs (rs568408, rs582054) in IL-12A and one SNP (rs428253) in EBI3 were selected. Blood samples were collected from 202 AD patients and 178 healthy individuals. SNPs in IL-35 genes were analysed by the polymerase chain reaction with sequence-specific primers (SSP-PCR) method. For IL-12A rs568408, the AA genotype was significantly linked to increased odds of AD (OR = 34.61; 95% CI: 2.06-579.97, p = 0.0137) and marginally associated with normal total serum IgE levels (OR = 2.82; 95% CI: 0.97-8.16; p = 0.05), while the GA genotype showed significantly reduced odds of AD (OR = 0.53; 95% CI: 0.34-0.81; p = 0.0035). In the context of IL-12A rs582054, TT genotype carriers had increased odds of AD (OR = 2.05; 95% CI: 1.08-3.85; p = 0.03). Patients with the GG genotype of EBI3 rs428253 had decreased odds of high total serum IgE levels (OR = 0.42; 95% CI: 0.20-0.86; p = 0.02) and milder pruritus severity compared to CC genotype carriers (4.12 vs. 7.50; p = 0.02). IL-35 genetic variations appear to play a role in AD pathogenesis.

Expression dynamics of microRNA-223/Ras-associated binding protein 12 axis in Stage III/Grade B periodontal disease: A case-control analysis.

The intricate interplay between periodontal polymicrobial flora and an altered immune response is the central cause of periodontal disease. Multiple cell death methods and their interactions, along with the associated signaling pathways, significantly impact the initiation and advancement of periodontitis. Our speculation revolves around the role of the miR-223/Ras-associated binding protein (RAB12) signaling axis in regulating autophagy-induced pyroptosis, contributing to the pathophysiology of periodontitis. Thus, this study aimed to investigate miR-223 and RAB12 expression patterns in Stage III/Grade B periodontal disease. The study included 50 healthy individuals and 50 patients diagnosed with Stage III/Grade B periodontal disease. Clinical parameters were cataloged for each participant. miRNA-223 underwent an in silico analysis to identify its potential target genes. Gingival crevicular fluid (GCF) samples were collected from the subjects for real-time polymerase chain reaction to evaluate the expression of both miR-223 and the RAB12 gene. The miRTargetLink2.0 analysis highlighted the RAB12 gene as a prime target for miR-223. In periodontal disease patients, miR-223 and RAB12 gene expressions significantly increased (15.21 and 34.70-fold changes, respectively; P < 0.05). Receiver operating characteristic analysis suggested that miR-223 is a potential biomarker for periodontal disease, with 76% diagnostic accuracy and an area under the curve of 0.777 (P < 0.01). MicroRNA-223 and its target gene RAB12 exhibit high expression levels in GCF samples from individuals with periodontal disease. This suggests modulation of autophagy and the signaling mechanism for pyroptotic cell death in periodontal tissues during pathogenesis. Consequently, the miR-223/RAB12 axis might represent a plausible link for periodontal disease.

Impact of microplastics on human health and aquatic species

Microplastics (MPs) have emerged as a pervasive environmental challenge, with significant implications for both marine ecosystems and human health. This study delves into the adverse effects of MPs, highlighting their physical, chemical, and biological impacts on marine life, particularly fish. These impacts include physical injury, oxidative stress, and altered immune responses, which can have cascading effects on marine biodiversity and ecosystem functionality. The review also underscores the risk MPs pose to humans through direct exposure, via consumption of contaminated seafood, inhalation, or dermal contact, potentially leading to oxidative stress, cytotoxic effects, and disturbances in immune function. By comprehensively examining existing research and identifying knowledge gaps, this study aims to underline the urgent need for targeted research strategies. These strategies should focus on elucidating the complex interactions between MPs and biological systems, assessing long-term health implications, and developing effective mitigation measures. Through detailed analysis of methodologies, results, and existing literature, this review aims to contribute to a deeper understanding of the multifaceted impact of microplastics, thereby guiding future research directions and informing policy decisions for the protection of marine ecosystems and human health.

Pre-vaccination Schistosoma mansoni and hookworm infections are associated with altered vaccine immune responses: a longitudinal analysis among adolescents living in helminth-endemic islands of Lake Victoria, Uganda.

Variations in vaccine responses have been observed between populations. A role for helminth infections has been proposed due to their immunomodulatory properties. In a secondary analysis of data from a randomised trial assessing effects of anthelminthic treatment on vaccine responses, we examined associations between helminth infections at baseline prior to vaccine administration, and vaccine responses among adolescents (9-17 years) in Koome Islands, Lake Victoria, Uganda. Participants received BCG [week 0], yellow fever (YF-17D), oral typhoid (Ty21a), HPV-prime [week 4], and HPV-boost, tetanus/diphtheria [week 28]. Outcomes were BCG-specific interferon-γ ELISpot responses and antibody responses to yellow-fever-, typhoid-, HPV-, tetanus- and diphtheria-specific antigens measured at two time points post vaccination. S. mansoni infection was determined as positive if either the plasma Circulating Anodic Antigen (CAA) assay or stool PCR were positive. Hookworm and Strongyloides were determined by stool PCR. Linear mixed effects regression was used to assess associations. Among 478 adolescents, 70% were Schistosoma mansoni (Sm) infected and 23% hookworm infected at baseline. Sm was associated with lower Salmonella Typhi O:LPS-specific IgG responses (adjusted geometric mean ratio (aGMR) 0.69 (0.57-0.83)), and hookworm with higher diphtheria-specific IgG (aGMR 1.16 (1.02, 1.31)) and lower HPV-16-specific IgG (aGMR 0.70 (0.55, 0.90)) post-vaccination. High Sm intensity was associated with lower BCG-specific interferon-γ and S. Typhi O:LPS-specific IgG. We found inverse associations between Sm and responses to two live vaccines, whereas hookworm was positively associated with diphtheria-specific IgG. These findings support the hypothesis that helminth infections can modulate vaccine responses, while also highlighting potential heterogeneity in the direction of these effects.

Inflammatory Markers and Fatigue in Individuals With Moderate to Severe Chronic Obstructive Pulmonary Disease.

Fatigue, a prevalent complex symptom among patients with chronic obstructive pulmonary disease (COPD), is considered an important clinical indicator of disease severity. However, the underlying mechanisms of COPD-related fatigue are not fully understood. This analysis explored the relationships between peripheral inflammatory markers and COPD-related fatigue in people with moderate to severe COPD. This is a secondary analysis of a longitudinal observational study of individuals with COPD examining the biological causes and functional consequences of depression. The data used in this study were collected at baseline. Systemic inflammation markers included C-reactive protein (CRP) and three pro-inflammatory cytokines consisting of interleukin-6 (IL-6), IL-8, and tumor necrosis factor-α. COPD-related fatigue was self-reported using the Chronic Respiratory Questionnaire. Covariates included age; gender; smoking status; disease severity; symptoms of depression, anxiety, and pain; and social support. Multivariable linear regression analyses were conducted. The sample included 300 adults living with COPD; 80% were male, and the average age was 67.6 years. Modest correlations were found between two systemic inflammatory markers (CRP and IL-8) and COPD-related fatigue. CRP was the only inflammatory marker significantly associated with fatigue symptoms after adjusting for covariates in multivariable analyses. Depression, pain, and education level were also significant predictors of COPD-related fatigue. The findings suggest that altered immune response based on CRP may contribute to COPD-related fatigue. Management of depression and pain may work as an effective treatment strategy for COPD-related fatigue. Further longitudinal studies with a broader range of inflammatory markers and multidimensional measures of fatigue symptoms are warranted.

Hyper-induction of IL-6 after TLR1/2 stimulation in calves with bovine respiratory disease.

Bovine respiratory disease (BRD) is a leading cause of mortality and compromised welfare in bovines. It is a polymicrobial syndrome resulting from a complex interplay of viral and bacterial pathogens with environmental factors. Despite the availability of vaccines, incidence and severity in young calves remains unabated. A more precise analysis of host innate immune responses during infection will identify improved diagnostic and prognostic biomarkers for early intervention and targeted treatments to prevent severe disease and loss of production efficiency. Here, we investigate hematological and innate immune responses using standardized ex-vivo whole blood assays in calves diagnosed with BRD. A total of 65 calves were recruited for this study, all between 2-8 weeks of age with 28 diagnosed with BRD by a thoracic ultrasonography score (TUS) and 19 by Wisconsin health score (WHS) and all data compared to 22 healthy controls from the same 9 study farms. Haematology revealed circulating immune cell populations were similar in both TUS positive and WHS positive calves compared to healthy controls. Gene expression analysis of 48 innate immune signalling genes in whole blood stimulated with TLR ligands was completed in a subset of calves. TLR1/2 stimulation with Pam3CSK4 showed a decreased pattern of expression in IL-1 and inflammasome related genes in addition to chemokine genes in calves with BRD. In response to TLR ligands LPS, Pam3CSK4 and R848, protein analysis of supernatant collected from all calves with BRD revealed significantly increased IL-6, but not IL-1β or IL-8, compared to healthy controls. This hyper-induction of IL-6 was observed most significantly in response to TLR1/2 stimulation in TUS positive calves. ROC analysis identified this induced IL-6 response to TLR1/2 stimulation as a potential diagnostic for BRD with a 74% true positive and 5% false positive detection rate for an IL-6 concentration >1780pg/mL. Overall, these results show altered immune responses specifically upon TLR1/2 activation is associated with BRD pathology which may contribute to disease progression. We have also identified induced IL-6 as a potentially informative biomarker for improved early intervention strategies for BRD.

Multi-faceted dysregulated immune response for COVID-19 infection explaining clinical heterogeneity

Clinical heterogeneity and varied prognosis are well noted for SARS-CoV-2 infection. Altered immune response is a major feature for the adverse prognosis however focus on altered immune response has been primarily limited to hyper-inflammatory responses like Cytokine storm. A deeper understanding of viral pathobiology and the interplay of innate and adaptive immune cells against SARS-CoV-2 infection is essential to optimize intervention strategy and future preparedness for SARS-CoV-2 or its related viral diseases. To uncover the immunological signatures driving the progression of SARS-CoV-2 infection, we performed an extensive immunophenotype on blood samples from 79 hospitalized patients with mild/moderate to severe infections as well as from healthy controls and recovered donors to understand the interplay between innate and adaptive responses impacting severity and prognosis. We observed multifarious immune dysregulation, varied across patients of the clinical spectrum. We observed 4 major dysregulations of immune phenotypes 1) depletion of M1φ (impaired antiviral response as APC), 2) immune suppression/exhaustion via activation of repressor like CD4+/CD8+PD1, TIM3, LAG3 3) inappropriate differentiation of lymphocyte (extreme elevated proportion of CD4 naive, memory B and T cells along with reduction of inflammatory activator like TLR2/4/TIGIT) and 4) cytokine storm. Our results show the identification of biomarkers to differentiate the different trajectories for SARS-CoV-2 infection.

Gut-Lung Axis in Focus: Deciphering the Impact of Gut Microbiota on Pulmonary Arterial Hypertension.

Recent advancements in the understanding of pulmonary arterial hypertension (PAH) have highlighted the significant role of the gut microbiota (GM) in its pathogenesis. This comprehensive review delves into the intricate relationship between the GM and PAH, emphasizing the influence of gut microbial composition and the critical metabolites produced. We particularly focus on the dynamic interaction between the gut and lung, examining how microbial dysbiosis contributes to PAH development through inflammation, altered immune responses, and changes in the gut-lung axis. Noteworthy findings include variations in the ratios of key bacterial groups such as Firmicutes and Bacteroidetes in PAH and the pivotal roles of metabolites like trimethylamine N-oxide (TMAO), short-chain fatty acids (SCFAs), and serotonin in the disease's progression. Additionally, the review elucidates potential diagnostic biomarkers and novel therapeutic approaches, including the use of probiotics and fecal microbiota transplantation, which leverage the gut microbiota for managing PAH. This review encapsulates the current state of research in this field, offering insights into the potential of gut microbiota modulation as a promising strategy in PAH diagnosing and treatment.

The DNA repair enzyme, aprataxin, plays a role in innate immune signaling.

Ataxia with oculomotor apraxia type 1 (AOA1) is a progressive neurodegenerative disorder characterized by a gradual loss of coordination of hand movements, speech, and eye movements. AOA1 is caused by an inactivation mutation in the APTX gene. APTX resolves abortive DNA ligation intermediates. APTX deficiency may lead to the accumulation of 5'-AMP termini, especially in the mitochondrial genome. The consequences of APTX deficiency includes impaired mitochondrial function, increased DNA single-strand breaks, elevated reactive oxygen species production, and altered mitochondrial morphology. All of these processes can cause misplacement of nuclear and mitochondrial DNA, which can activate innate immune sensors to elicit an inflammatory response. This study explores the impact of APTX knockout in microglial cells, the immune cells of the brain. RNA-seq analysis revealed significant differences in the transcriptomes of wild-type and APTX knockout cells, especially in response to viral infections and innate immune pathways. Specifically, genes and proteins involved in the cGAS-STING and RIG-I/MAVS pathways were downregulated in APTX knockout cells, which suggests an impaired immune response to cytosolic DNA and RNA. The clinical relevance of these findings was supported by analyzing publicly available RNA-seq data from AOA1 patient cell lines. Comparisons between APTX-deficient patient cells and healthy control cells also revealed altered immune responses and dysregulated DNA- and RNA-sensing pathways in the patient cells. Overall, this study highlights the critical role of APTX in regulating innate immunity, particularly in DNA- and RNA-sensing pathways. Our findings contribute to a better understanding of the underlying molecular mechanisms of AOA1 pathology and highlights potential therapeutic targets for this disease.

Changes in neuroinflammatory markers and microglial density in the hippocampus and prefrontal cortex of the C58/J mouse model of autism.

Autism spectrum disorder (ASD) is a diverse group of neurodevelopmental conditions with complex origins. Individuals with ASD present various neurobiological abnormalities, including an altered immune response in the central nervous system and other tissues. Animal models like the C58/J inbred mouse strain are used to study biological characteristics of ASD. This strain is considered an idiopathic autism model because of its demonstrated reduced social preference and repetitive behaviours. Notably, C58/J mice exhibit alterations in dendritic arbour complexity, density and dendritic spines maturation in the hippocampus and prefrontal cortex (PFC), but inflammatory-related changes have not been explored in these mice. In this study, we investigated proinflammatory markers in the hippocampus and PFC of adult male C58/J mice. We discovered elevated levels of interferon gamma (IFN-γ) and monocyte chemoattractant protein 1 (MCP-1) in the hippocampus, suggesting increased inflammation, alongside a reduction in the anti-inflammatory enzyme arginase 1 (ARG1). Conversely, the PFC displayed reduced levels of TNF-α and MCP-1. Microglial analysis revealed higher levels of transmembrane protein 119 (TMEM119) and increased microglial density in a region-specific manner of the autistic-like mice, particularly in the PFC and hippocampus. Additionally, an augmented expression of the fractalkine receptor CX3CR1 was observed in the hippocampus and PFC of C58/J mice. Microglial morphological analysis shows no evident changes in the hippocampus of mice with autistic-like behaviours versus wild-type strain. These region-specific changes can contribute to modulate processes like inflammation or synaptic pruning in the C58/J mouse model of idiopathic autism.

Debate 6: Microbiome Testing is Indicated for Implantation Failure in 2023

Motion: For Uninvestigated Recurrent Implantation Failure (RIF) has a significant cost, can waste embryos with the potential for life and leads to empirical therapies such as the use of steroids. Chronic Endometritis (CE) is a known cause of RIF is diagnosed by presence of plasma cells and worsens if steroids suppress the protective immune system response. Identifying plasma cells in endometrial tissue samples requires histological expertise, special staining and there is variation in numbers between tissue sections and microscope fields. Furthermore, culturing bacteria from low biomass environments like the endometrium is difficult and will not identify anaerobes and other fastidious organisms. The molecular technique of sequencing the 16S ribosome enables the identification of microbes that can create a hostile environment for embryos. There is clear evidence that some microbes and microbiome signatures are associated with RIF and that changing the microbiome is associated with higher implantation rates. There are established and emerging treatments for an aberrant microbiome that include antibiotic therapy, probiotics, faecal transplantation, and curettage. The more diagnostic information we can obtain to determine the cause of our patients RIF and then design specific, targeted treatments that are effective, the better their pregnancy outcomes will be. It is useful to test the microbiome and will only become more useful as this technology improves. Motion: Against The microbiome is closely related to women’s reproductive health, and therefore microbiome testing is becoming increasingly important in the field of reproductive medicine, especially in guiding assisted reproduction treatments such as infertility. The human microbiome is a collection of all microorganisms that exist on or within human tissues and fluids, as well as the corresponding anatomical sites where they are located, including the female reproductive tract, gastrointestinal tract, skin, semen, saliva, oral mucous membranes, etc., of which the ones that are most relevant to the study of female infertility mainly include the female reproductive tract flora and gastrointestinal tract flora. Several studies have shown that the composition of the microbiota in the female reproductive tract may affect embryo implantation and pregnancy success. An imbalanced or dysbiased microbiome of the female reproductive tract flora may lead to inflammation, altered immune responses, and hinder the optimal conditions needed for successful embryo implantation. Microbiome Testing can be accomplished through a variety of technologies, such as next-generation sequencing, which allows for a comprehensive analysis of microbial composition. Thus, microbiome testing that involves analyzing the microbial community in the female reproductive tract for imbalance or dysbiosis is a breakthrough point with great potential to aid in the treatment of recurrent implantation failure. For recurrent implantation failures, microbiome testing can help fertility specialists tailor a personalized treatment plan. By understanding an individual’s specific microbial profile, physicians can make informed decisions about potential interventions such as antibiotic therapy, probiotics, or other microbial modulation therapies. Of course, the use of microbiome testing should be carefully considered on a case-by-case basis and should be used in conjunction with other diagnostic tools and assessments to provide optimal treatment for patients with implantation failure.

Modulation of microglial function by neuronal expression of the Alzheimer multifactorial therapeutic agent E2F4DN is mediated by a soluble factor

AbstractBackgroundAlzheimer’s disease (AD) is a neurodegenerative disorder in which altered immune response is an important etiological factor (Cell Rep. 2019;27:1293.e6‐1306.e6, Nature 2019;575:669‐673). The transcription factor E2F4 regulates gene networks affected in AD (Interdiscip. Sci. 2019;11:226‐236), thus constituting a potential target for intervention. Neuronal expression of a dominant negative form of E2F4 (E2F4DN), which cannot be phosphorylated in two conserved Thr residues, can attenuate microgliosis in a mouse model of AD (Neurotherapeutics 2021;18:2484‐2503, Mol. Neurobiol. 2022;59:3016‐30392), as evidenced by the reduction of area occupied by microglia (i.e. Iba1‐positive cells). Communication between neurons and microglia is essential to regulate microglial activation and neuroprotection. The loss of this communication can cause microglia overactivation and produce persistent inflammation, finally resulting in the exacerbation of the neuropathology (Neural Regen. Res. 2019;14:1499‐1502).MethodMouse cortical neurons were cultured and maintained for 9 days in vitro (DIV) for maturation. Neurons were then transfected with an E2F4DN adenoviral (Ad5) vector, or a control EGFP Ad5 vector. After 48 h, rat microglia were treated for 24 hours with the conditioned media, and then fixed and immunostained with the microglia marker Iba1. The size of these cells was analyzed as a readout of the glial inflammatory activity (Sci. Rep. 2017;7:1576).ResultMicroglial cell size was analyzed from images obtained in the fluorescence microscope. This would determine if any soluble factor secreted by neurons that express E2F4DN, but not by neurons that express EGFP, is capable of inducing morphological changes that may reflect functional changes in this cell type. A reduction in the size of microglia was observed when the conditioned medium came from neurons expressing E2F4DN. These results show the existence of a differential communication mechanism between neurons and microglia depending on the expression of E2F4DN.ConclusionWe suggest that there is an E2F4DN‐dependent neuron‐microglia communication based on soluble factors such as those described by Simon et al. (Neuroscience 2019;405:24‐34). Altogether, our data are consistent with a beneficial immune response elicited by neurons expressing E2F4DN, a molecule proposed as a multifactorial therapeutic agent against AD.

Altered response to Toll-like receptor 4 activation in fibromyalgia: A low-dose, human experimental endotoxemia pilot study

In this pilot study, a human intravenous injection of low-dose endotoxin (lipopolysaccharide, LPS) model was used to test if fibromyalgia is associated with altered immune responses to Toll-like receptor 4 (TLR4) activation. Eight women with moderately-severe fibromyalgia and eight healthy women were administered LPS at 0.1 ng/kg in session one and 0.4 ng/kg in session two. Blood draws were collected hourly to characterize the immune response. The primary analytes of interest, leptin and fractalkine, were assayed via commercial radioimmunoassay and enzyme-linked immunosorbent assay kits, respectively. Exploratory analyses were performed on 20 secreted cytokine assays by multiplex cytokine panels, collected hourly. Exploratory analyses were also performed on testosterone, estrogen, and cortisol levels, collected hourly. Additionally, standard clinical complete blood counts with differential (CBC-D) were collected before LPS administration and at the end of the session. The fibromyalgia group demonstrated enhanced leptin and suppressed fractalkine responses to LPS administration. In the exploratory analyses, the fibromyalgia group showed a lower release of IFN-γ, CXCL10, IL-17A, and IL-12 and higher release of IL-15, TARC, MDC, and eotaxin than the healthy group. The results of this study suggest that fibromyalgia may involve an altered immune response to TLR4 activation.

Brain-Splenic Immune System Interactions in Hypertension: Cellular and Molecular Mechanisms.

Hypertension represents a major worldwide cause of death and disability, and it is becoming increasingly clear that available therapies are not sufficient to reduce the risk of major cardiovascular events. Various mechanisms contribute to blood pressure increase: neurohormonal activation, autonomic nervous system imbalance, and immune activation. Of note, the brain is an important regulator of blood pressure levels; it recognizes the peripheral perturbation and organizes a reflex response by modulating immune system and hormonal release to attempt at restoring the homeostasis. The connection between the brain and peripheral organs is mediated by the autonomic nervous system, which also modulates immune and inflammatory responses. Interestingly, an increased autonomic nervous system activity has been correlated with an altered immune response in cardiovascular diseases. The spleen is the largest immune organ exerting a potent influence on the cardiovascular system during disease and is characterized by a dense noradrenergic innervation. Taken together, these aspects led to hypothesize a key role of neuroimmune mechanisms in the onset and progression of hypertension. This review discusses how the nervous and splenic immune systems interact and how the mechanisms underlying the neuroimmune cross talk influence the disease progression.