Altered Immune Function Research Articles

The transmission of hepatitis B virus (HBV) infection from mother-to-infant (MTI) and the susceptibility of offspring to hepatitis B under intrauterine exposure to HBsAg.

Hepatitis B virus (HBV) causes long-term injury to the liver in patients with chronic hepatitis B. It was reported that nearly half of this disease's cases now result from mother-to-infant (MTI) transmission. Therefore, intervention during this period of transmission of HBV could effectively prevent HBV infection in infants. This study employed bioinformatics methods to analyze the datasets of MTI hepatitis B transmission obtained from the Gene Expression Omnibus (GEO) database. Through this analysis, we extracted valuable information to identify genes exhibiting differential expression and uncover the associated signal pathways. Ultimately, our investigations into alterations in immune function shed light on the underlying mechanisms of MTI HBV transmission. There were 593 genes that were significantly differentially expressed (512 up-regulated genes and 81 down-regulated genes) in the offspring CD8+T cells with Hepatitis B surface antigen (HBsAg) intrauterine exposure. The pathways enriched for differentially expressed genes have been revealed. Furthermore, we performed a correlation analysis between differentially expressed genes and maternal hepatitis B inheritance via the weighted gene co-expression network analysis (WGCNA) and eventually found a high correlation between the cyan module and the shape. Among them, there were 166 genes in the cyan module, which were mainly enriched in the phosphatidylinositol signaling system, glycerolipid metabolism, and other types of O-Glycan biosynthesis. Therefore, we speculated that these signaling pathways and the genes within may be closely related to hepatitis B susceptibility and maternal hepatitis B inheritance. In this study, we showed that differentially expressed genes and signaling pathways may be valuable in preventing MTI transmission of HBV.

Epigenetic memory of coronavirus infection in innate immune cells and their progenitors

Inflammation can trigger lasting phenotypes in immune and non-immune cells. Whether and how human infections and associated inflammation can form innate immune memory in hematopoietic stem and progenitor cells (HSPC) has remained unclear. We found that circulating HSPC, enriched from peripheral blood, captured the diversity of bone marrow HSPC, enabling investigation of their epigenomic reprogramming following coronavirus disease 2019 (COVID-19). Alterations in innate immune phenotypes and epigenetic programs of HSPC persisted for months to 1 year following severe COVID-19 and were associated with distinct transcription factor (TF) activities, altered regulation of inflammatory programs, and durable increases in myelopoiesis. HSPC epigenomic alterations were conveyed, through differentiation, to progeny innate immune cells. Early activity of IL-6 contributed to these persistent phenotypes in human COVID-19 and a mouse coronavirus infection model. Epigenetic reprogramming of HSPC may underlie altered immune function following infection and be broadly relevant, especially for millions of COVID-19 survivors.

"HLA-C: evolution, epigenetics, and pathological implications in the major histocompatibility complex".

HLA-C, a gene located within the major histocompatibility complex, has emerged as a prominent target in biomedical research due to its involvement in various diseases, including cancer and autoimmune disorders; even though its recent addition to the MHC, the interaction between HLA-C and KIR is crucial for immune responses, particularly in viral infections. This review provides an overview of the structure, origin, function, and pathological implications of HLA-C in the major histocompatibility complex. In the last decade, we systematically reviewed original publications from Pubmed, ScienceDirect, Scopus, and Google Scholar. Our findings reveal that genetic variations in HLA-C can determine susceptibility or resistance to certain diseases. However, the first four exons of HLA-C are particularly susceptible to epigenetic modifications, which can lead to gene silencing and alterations in immune function. These alterations can manifest in diseases such as alopecia areata and psoriasis and can also impact susceptibility to cancer and the effectiveness of cancer treatments. By comprehending the intricate interplay between genetic and epigenetic factors that regulate HLA-C expression, researchers may develop novel strategies for preventing and treating diseases associated with HLA-C dysregulation.

Immune modulation by nutritional intervention in malnourished children: Identifying the phenotypic distribution and functional responses of peripheral blood mononuclear cells.

Malnourished children are susceptible to an increased risk of mortality owing to impaired immune functions. However, the underlying mechanism of altered immune functions and its interaction with malnutrition is poorly understood. This study investigates the immune function and evaluates the effect of a particular nutritional intervention on the immune cells of undernourished children. Stunted (LAZ <-2) and at-risk of being stunted (length-for-age Z-scores, LAZ <-1 to -2) children aged between 12 and 18 months were enrolled and were provided with the daily nutritional intervention of one egg and 150 mL cow's milk for 90 days. Peripheral blood mononuclear cells (PBMCs) were isolated at enrolment and upon completion of the intervention. Phenotypic profiles for CD3+ cells, CD4+ cells, CD8+ cells, NKT cells, and B cells were similar in both cohorts, both before and after the intervention. However, activated B cells (CD25+) were increased after nutritional intervention in the at-risk of being stunted cohort. Several pro-inflammatory cytokines, IL-6, IFN-γ, and TNF-α, were elevated in the stunted children following the nutritional intervention. The results of the study indicate that nutritional intervention may have a role on activated B cells (CD25+) s in children who are at-risk of being stunted and may alter the capacity of PBMC to produce inflammatory cytokines in stunted children.

Defining the Relationship of Gut Microbiota, Immunity, and Cognition in Early Life-A Narrative Review.

Recently, the immune system has been identified as one of the possible main bridges which connect the gut-brain axis. This review aims to examine available evidence on the microbiota-immunity-cognitive relationship and its possible effects on human health early in life. This review was assembled by compiling and analyzing various literature and publications that document the gut microbiota-immune system-cognition interaction and its implications in the pediatric population. This review shows that the gut microbiota is a pivotal component of gut physiology, with its development being influenced by a variety of factors and, in return, supports the development of overall health. Findings from current research focus on the complex relationship between the central nervous system, gut (along with gut microbiota), and immune cells, highlighting the importance of maintaining a balanced interaction among these systems for preserving homeostasis, and demonstrating the influence of gut microbes on neurogenesis, myelin formation, the potential for dysbiosis, and alterations in immune and cognitive functions. While limited, evidence shows how gut microbiota affects innate and adaptive immunity as well as cognition (through HPA axis, metabolites, vagal nerve, neurotransmitter, and myelination).

The Art of Psychoneuroimmunology in Menopause Management

Psychoneuroimmunology is a field that explores the intricate connections between the mind, brain, and immune system. This narrative review integrates various aspects of psychoneuroimmunology in the context of menopause. It highlights the hormonal changes during menopause, their impact on psychological well-being and the immune system, as well as the psychological aspects of menopause such as emotional changes, cognitive functioning, and sleep disturbances. The immunological changes during menopause, including alterations in immune cell function and cytokine production, are discussed along with their influence on psychological well-being. This comprehensive review emphasizes the bidirectional communication between the brain and immune system, the effects of hormonal, psychological, and immunological factors on each other, and the role of chronic inflammation in menopause-related psychological symptoms. Additionally, it explores the influence of psychosocial factors like stress and social support on menopausal symptoms, and presents various psychoneuroimmunology interventions such as mind-body techniques, pharmacological options, and lifestyle modifications. The importance of integrating psychoneuroimmunology approaches in menopause research, potential areas for further investigation, and the call for comprehensive strategies to improve menopausal care are also highlighted, underscoring the significance of this interdisciplinary field in understanding and enhancing menopausal health and well-being.

Females with Increased Costs Maintain Reproductive Output: A Field Experiment in a Common Songbird.

Reproduction and self-maintenance are energetically costly activities involved in classic life history trade-offs. However, few studies have measured the responses of wild organisms to simultaneous changes in reproductive and self-maintenance costs, which may have interactive effects. In free-living female Barn Swallows (Hirundo rustica), we simultaneously manipulated reproductive costs (by adding or removing two nestlings) and self-maintenance costs (by attaching a ∼1 g weight in the form of a GPS tag to half of our study birds) and measured mass, immune status, blood glucose, feather growth, and reproductive output (likelihood of a second clutch, number of eggs, and time between clutches). GPS tags allowed us to analyze how movement range size affected response to brood size manipulation. Tagging altered females' immune function as evidenced by an elevated heterophil to lymphocyte (H:L) ratio, but all females were equally likely to lay more eggs. There was no evidence of interactive effects of the tagging and brood size treatment. Range size was highly variable, and birds with large ranges grew feathers more slowly, but analyzing the effect of brood size manipulation while accounting for variation in range size did not result in any physiological response. Our results support the theoretical prediction that short-lived vertebrates do face a trade-off between reproduction and self-maintenance and, when faced with increased costs, tend to preserve investment in reproduction at the expense of parental condition. This experiment also helps us to understand how movement patterns may be relevant to life history trade-offs in wild birds.

Immunodeficiency in a female patient with Incontinentia Pigmenti

Incontinentia pigmenti (IP) is a rare X-linked dominant neuroectodermal disorder characterized by ocular, dermatologic, and neurological abnormalities. It is caused by heterozygous mutations in IKBKG (NEMO), which encodes a regulatory factor involved in NF-kB activation. Random and skewed X-inactivation allows for female survival and determines extent of disease. Although immune function is typically normal in IP patients, hypomorphic IKBKG mutations are known to cause immunodeficiency, as occurs in X-linked NEMO deficiency. A female newborn presented with bullous vesicles, peeling skin, alopecia, hearing loss, and tonic-clonic seizures with MRI demonstrating evidence of in utero stroke. She developed intermittent fevers and cellulitis and was diagnosed with IP based on clinical findings. Following discharge, she was readmitted at 1 month of age due to bronchiolitis complicated by pulmonary abscess. Labs demonstrated hyperleukocytosis with hypereosinophilia, normal T, B, and NK lymphocyte enumeration, abnormal lymphocyte proliferation to phytohemagglutinin (PHA) and anti-CD3, and abnormal toll-like receptor (TLR) function. Genetic analysis revealed a heterozygous deletion of exons 4–10 in IKBKG. Labs at 1 year follow up showed normal lymphocyte (T, B, and NK) enumeration and mitogen responses, normal immunoglobulin levels, and normal responses to pneumococcal and tetanus vaccines. While about 70% of IP patients harbor a deletion of exons 4–10 in IKBKG. unlike other hypomorphic NEMO mutations, this mutation is not typically associated with altered immune function. This case highlights that immunodeficiency may be an early clinical manifestation in female patients with IP.

Insufficient epitope specific T cell clones is responsible for impaired cellular immunity to inactivated SARS-CoV-2 vaccine in the elderly

Abstract Aging is a critical risk factor for SARS-CoV-2 vaccine efficacy. Although low humoral immunity in the elderly was observed in mRNA and recombinant protein vaccination, the immune responses to inactivated vaccine in the elderly, and the underlying mechanisms of differences to young, if any, are still unclear. Here, we studied a cohort of 121 young (18–30 years old) and 48 old (60–85 years old) donors vaccinated with inactivated SARS-CoV-2 and demonstrate that the neutralizing antibody response is slower in the elderly, but eventually reached the similar level to day 7 post-vaccination in young. We identified a range of epitopes targeted by CD8 T cells that were underrepresented in immune responses in the old group, especially when measured with tetramers derived from the 13 major SARS-CoV-2 variants. Comparison of the transcriptomes of B, CD4 and CD8 T cells from pre- and post-vaccinated young and elderly revealed genes potentially responsible for low immune responses in elderly, functionally related to antigen processing and presentation. We further built an epitope specific TCR repertoire database using single-cell RNA and TCR sequencing. Statistical and machine-learning based analyses demonstrated that SARS-CoV-2 epitope specific CD8 T cell clones were significantly lower in the old than young, and failed to be boosted after vaccination in elderly. Comparison of BCRs and TCRs from pre- and post-vaccinated young and elderly individuals revealed inadequate receptor repertoire size and diversity might be responsible for low immune response in the elderly. Together, the altered immune cell function and the attenuated antigen specific TCR repertoire were responsible for the impaired CD8 T cell immune response in the elderly. This work was supported by grants from the National Key Research and Development Program of China (2018YFC2002003 to G.C., 2021YFC2009400 to G.Z.), the Natural Science Foundation of China (U1801285 and 92169102 to G.C., 81971301 and 32050410285 to O.J.L., 82201954 to Z.R.)

Epigenetic Memory of COVID-19 in Innate Immune Cells and Their Progen-itors--

Abstract Through epigenetic mechanisms, systemic inflammation may trigger innate immune memory and persistent changes in hematopoietic cells; however, it has been difficult to investigate these phenotypes in the context of human disease, such as severe coronavirus disease 2019 (COVID-19). We developed a new workflow to isolate circulating hematopoietic stem and progenitor cells (HSPC) from peripheral blood, combining single-cell RNA/ATAC-seq. With this method, we were able to capture the diversity of circulating HSPC as seen in bone marrow, allowing for the non-invasive investigation of hematopoiesis as well as epigenomic changes after COVID-19. Following severe COVID-19, we observed both transcriptomic and epigenetic changes in HSPC and its progeny innate immune cells, and they persisted for months to a year. Different transcription factor activities (including IRF, AP-1, and CTCF) were associated with these alterations, which altered the regulation of inflammatory programs. Severe COVID-19 patients’ HSPC displayed long-lasting increases in myelopoiesis and granulopoiesis, and circulating monocytes responded more strongly to subsequent stimulation. We found that epigenomic changes in HSPC were retained and passed onto differentiated progeny innate immune cells. In addition, we demonstrate that administration of an anti-IL-6 blockade during acute severe COVID-19 can normalize the persistent phenotypes, suggesting that IL-6 plays a role in the development of epigenetic memory. In conclusion, epigenetic reprogramming of HSPC may underlie altered immune function subsequent to infection and has broad applicability, particularly for millions of COVID-19 survivors with incomplete recovery.

Abstract 796: Altered immune response to vaccination in patients with plasma cell premalignancy

Abstract Introduction Patients with hematological malignancies, including multiple myeloma (MM), experience sub-optimal responses to SARS-CoV-2 vaccination. Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smoldering Multiple Myeloma (SMM) are precursors to MM and exhibit altered immune cell composition and function. The SARS-CoV-2 pandemic and the subsequent population-wide vaccination represent an opportunity to study the real-life immune response to a common antigen. Here, we present updated results from the IMPACT study, a study we launched in November 2020 to characterize the effect of plasma cell premalignancy on response to SARS-CoV-2 vaccination (vx). Methods We performed: (i) ELISA for SARS-CoV-2-specific antibodies on 1,887 peripheral blood (PB) samples (237 healthy donors (HD), and 550 MGUS, 947 SMM, and 153 MM patients) drawn pre- and post-vx; (ii) single-cell RNA, T cell receptor (TCR), and B cell receptor (BCR) sequencing (10x Genomics) on 224 PB samples (26 HD, and 20 MGUS, 48 SMM, and 24 MM patients) drawn pre- and post-vx; (iii) plasma cytokine profiling (Olink) on 106 PB samples (32 HD, and 38 MGUS and 36 SMM patients) drawn pre- and post-vx; and (iv) bulk TCR sequencing (Adaptive Biotechnologies) on 8 PB samples from 4 patients (2 MGUS, 2 SMM) drawn pre- and post-vx. Results Patients with MGUS and SMM achieved comparable antibody titers to HD two months post-vx. However, patient titers waned significantly faster, and 4 months post-vx we observed significantly lower titers in both MGUS (Wilcoxon rank-sum, p=0.030) and SMM (p=0.010). These results indicate impaired humoral immune response in patients with MGUS and SMM.At baseline, the TCR repertoire was significantly less diverse in patients with SMM compared to HD (Wilcoxon rank-sum, p=0.039), while no significant difference was observed in the BCR repertoire (p=0.095). Interestingly, a significant increase in TCR repertoire diversity was observed post-vx in patients with SMM (paired t-test, p=0.014), indicating rare T cell clone recruitment in response to vaccination. In both HD and patients, recruited clones showed upregulation of genes associated with CD4+ naïve and memory T cells, suggesting preservation of the T cell response in SMM, which was confirmed by bulk TCR-sequencing in 4 patients.Lastly, by cytokine profiling, we observed a defect in IL-1β and IL-18 induction post-vx in patients with SMM compared to HD (Wilcoxon rank-sum, p=0.047 and p=0.015, respectively), two key monocyte-derived mediators of acute inflammation, suggesting an altered innate immune response as well. Conclusion Taken together, our findings highlight that despite the absence of clinical manifestations, plasma cell premalignancy is associated with defects in both innate and adaptive immune responses. Therefore, patients with plasma cell premalignancy may require adjusted vaccination strategies for optimal immunization. Citation Format: Yoshinobu Konishi, Romanos Sklavenitis-Pistofidis, Michelle P. Aranha, Ting Wu, Hong Yue, Elizabeth D. Lightbody, Mahshid Rahmat, Michael Timonian, Shohreh Varmeh, Daniel Heilpern-Mallory, Michael P. Agius, Nang K. Su, Jacqueline Perry, Erica Horowitz, Maya I. Davis, Anna V. Justis, Radosław P. Nowak, Mark Hamilton, Daniel Auclair, Catherine R. Marinac, Eric S. Fischer, Gad Getz, Irene M. Ghobrial. Altered immune response to vaccination in patients with plasma cell premalignancy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 796.

Differences of gut microbiota and behavioral symptoms between two subgroups of autistic children based on γδT cells-derived IFN-γ Levels: A preliminary study.

Autism Spectrum Disorders (ASD) are defined as a group of pervasive neurodevelopmental disorders, and the heterogeneity in the symptomology and etiology of ASD has long been recognized. Altered immune function and gut microbiota have been found in ASD populations. Immune dysfunction has been hypothesized to involve in the pathophysiology of a subtype of ASD. A cohort of 105 ASD children were recruited and grouped based on IFN-γ levels derived from ex vivo stimulated γδT cells. Fecal samples were collected and analyzed with a metagenomic approach. Comparison of autistic symptoms and gut microbiota composition was made between subgroups. Enriched KEGG orthologues markers and pathogen-host interactions based on metagenome were also analyzed to reveal the differences in functional features. The autistic behavioral symptoms were more severe for children in the IFN-γ-high group, especially in the body and object use, social and self-help, and expressive language performance domains. LEfSe analysis of gut microbiota revealed an overrepresentation of Selenomonadales, Negatiyicutes, Veillonellaceae and Verrucomicrobiaceae and underrepresentation of Bacteroides xylanisolvens and Bifidobacterium longum in children with higher IFN-γ level. Decreased metabolism function of carbohydrate, amino acid and lipid in gut microbiota were found in the IFN-γ-high group. Additional functional profiles analyses revealed significant differences in the abundances of genes encoding carbohydrate-active enzymes between the two groups. And enriched phenotypes related to infection and gastroenteritis and underrepresentation of one gut-brain module associated with histamine degradation were also found in the IFN-γ-High group. Results of multivariate analyses revealed relatively good separation between the two groups. Levels of IFN-γ derived from γδT cell could serve as one of the potential candidate biomarkers to subtype ASD individuals to reduce the heterogeneity associated with ASD and produce subgroups which are more likely to share a more similar phenotype and etiology. A better understanding of the associations among immune function, gut microbiota composition and metabolism abnormalities in ASD would facilitate the development of individualized biomedical treatment for this complex neurodevelopmental disorder.

Anti-inflammatory effects of 2nd generation antipsychotics in patients with schizophrenia: A systematic review and meta-analysis

BackgroundSchizophrenia is a major psychiatric disorder with unknown aetiology. Recent evidence suggests a potential role for cytokines in its pathophysiology and that antipsychotic medication may alter this. While the aetiology of schizophrenia remains only partly understood, an altered immune function representing an important avenue of further discovery. In this systematic review and meta-analysis we focus on the specific effects of second generation antipsychotics risperidone and clozapine on inflammatory cytokines. MethodsA defined systematic search of PubMed and Web of Science databases was performed to identify relevant studies published between Jan 1900 and May 2022. After screening of 2969 papers, 43 studies (27 single-arm and 8 dual-arm) were included that consisted of a total of 1421 patients with schizophrenia in the systematic review. From these, twenty studies (4 dual-arm; 678 patients) had data available on which a meta-analysis could be carried out. ResultsOur meta-analysis showed a significant reduction of pro-inflammatory cytokines post-risperidone treatment in the absence of a similar association with clozapine. Subgroup analyses (First episode v chronic) demonstrated that duration of illness influenced the extent of cytokine alteration; risperidone treatment produced significant cytokine changes (lowered IL-6 and TNF-α) in chronic patients but not in first-episode psychosis (FEP) patients. ConclusionVarying treatment effects on cytokines can be observed by the use of different antipsychotic drugs. The cytokine alterations post-treatment are influenced by the specific antipsychotic drugs and patient status. This may explain disease progression in certain patient groups and influence therapeutic choices in the future.

Evolutive emergence and divergence of an Ig regulatory node: An environmental sensor getting cues from the aryl hydrocarbon receptor?

One gene, the immunoglobulin heavy chain (IgH) gene, is responsible for the expression of all the different antibody isotypes. Transcriptional regulation of the IgH gene is complex and involves several regulatory elements including a large element at the 3' end of the IgH gene locus (3'RR). Animal models have demonstrated an essential role of the 3'RR in the ability of B cells to express high affinity antibodies and to express different antibody classes. Additionally, environmental chemicals such as aryl hydrocarbon receptor (AhR) ligands modulate mouse 3'RR activity that mirrors the effects of these chemicals on antibody production and immunocompetence in mouse models. Although first discovered as a mediator of the toxicity induced by the high affinity ligand 2,3,7,8-tetracholordibenzo-p-dioxin (dioxin), understanding of the AhR has expanded to a physiological role in preserving homeostasis and maintaining immunocompetence. We posit that the AhR also plays a role in human antibody production and that the 3'RR is not only an IgH regulatory node but also an environmental sensor receiving signals through intrinsic and extrinsic pathways, including the AhR. This review will 1) highlight the emerging role of the AhR as a key transducer between environmental signals and altered immune function; 2) examine the current state of knowledge regarding IgH gene regulation and the role of the AhR in modulation of Ig production; 3) describe the evolution of the IgH gene that resulted in species and population differences; and 4) explore the evidence supporting the environmental sensing capacity of the 3'RR and the AhR as a transducer of these cues. This review will also underscore the need for studies focused on human models due to the premise that understanding genetic differences in the human population and the signaling pathways that converge at the 3'RR will provide valuable insight into individual sensitivities to environmental factors and antibody-mediated disease conditions, including emerging infections such as SARS-CoV-2.

Age-Related Alterations in Immune Function and Inflammation: Focus on Ischemic Stroke.

The aging of the global population poses significant scientific challenges. Moreover, the biological process of aging is the most significant risk factor for most chronic illnesses; therefore, understanding the molecular and cellular mechanisms underlying these aging-related challenges is crucial for extending the healthy lifespan of older individuals. Preventing brain aging remains a priority public health goal, and integrative and comprehensive aging analyses have revealed that immunosenescence is a potential cause of age-related brain damage and disease (e.g., stroke). Importantly, the neuroinflammatory and immune systems present two-way contact and thus can affect each other. Emerging evidence supports the numerous effects of immunosenescence- and inflammation-mediated immunity in neurologically injured brains. In this study, we briefly outline how aging alters the pathophysiology and transcriptional amplitude in patients who experienced stroke and then discuss how the immune system and its cellular components and molecular mechanisms are affected by age after stroke. Finally, we highlight emerging interventions with the potential to slow down or reduce aging and prevent stroke onset.

An understanding of the immune dysfunction in susceptible people who develop the post-viral fatigue syndromes Myalgic Encephalomyelitis/Chronic Fatigue Syndrome and Long COVID

Viral infection in most people results in a transient immune/inflammatory response resulting in elimination of the virus and recovery where the immune system returns to that of the pre-infectious state. In susceptible people by contrast there is a transition from an acute immune response to a chronic state that can lead to an ongoing lifelong complex post-viral illness, Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. This susceptibility is proposed to be genetic or be primed by prior health history. Complex abnormalities occur in immune cell functions, immune cell metabolism and energy production, and in cytokine immune modulator regulation. The immune system of the brain/central nervous system becomes activated leading to dysfunction in regulation of body physiology and the onset of many neurological symptoms. A dysfunctional immune system is core to the development of the post-viral condition as shown with diverse strategies of immune profiling. Many studies have shown changes in numbers and activity of immune cells of different phenotypes and their metabolism. Immune regulating cytokines show complex altered patterns and vary with the stage of the disease, and there are elements of associated autoimmunity. These complex changes are accompanied by an altered molecular homeostasis with immune cell transcripts and proteins no longer produced in a tightly regulated manner, reflected in the instability of the epigenetic code that controls gene expression. Potential key elements of the altered immune function in this disease needing further exploration are changes to the gut-brain-immune axis as a result of changes in the microbiome of the gut, and viral reactivation from latent elements of the triggering virus or from a prior viral infection. Long COVID, an Myalgic Encephalomyelitis/Chronic Fatigue Syndrome-like illness, is the post-viral condition that has arisen in large numbers solely from the pandemic virus Severe Acute Respiratory Syndrome Coronovirus-2. With over 760 million cases worldwide, an estimated ~100 million cases of Long COVID have occurred within a short period. This now provides an unprecedented opportunity to understand the progression of these post-viral diseases, and to progress from a research phase mainly documenting the immune changes to considering potential immunotherapies that might improve the overall symptom profile of affected patients, and provide them with a better quality of life.

TH1/Treg ratio may be a marker of autism in children with immune dysfunction

Evidence suggests a link between autism spectrum disorder (ASD), behavioral symptoms in the context of ASD, and presence of an altered immune function. Several studies have highlighted differences in T-lymphocyte subpopulations, their activation status, and their response to stimulation in children and adults with ASD. These T cell abnormalities have often been associated with more impaired behaviors. However, few studies have attempted to address whether T cell subsets have the potential to serve as biomarkers in ASD. Moreover, although many studies have been performed in Western populations, few (if any) have been performed in Asian populations in mainland China. In this study we used intracellular cytokine flow cytometry to assess the frequencies of CD4+ T-cell subpopulations (T-helper (TH) 1, TH2, TH17, Foxp3+ regulatory T cells (Treg) as well as CD8+, subpopulations of T cytotoxic (TC) 1, TC2, and TC17 in 82 children with ASD and 50 healthy typical developing children from the Second Affiliated Hospital of Kunming Medical University of Yunnan province. To further elucidate immune status cytokine levels were also measured in the plasma and serum using a bead-based cytokine assay. Our results showed that the frequency of circulating Treg cells and the levels of active TGF-β1 in plasma were lower in children with ASD than in healthy controls. In contrast, the frequencies of TH1, TH2, TH17 and TC1 cells were increased. Proinflammatory cytokine levels of TNF-α, IL-4, IL-5 and IL-17A were higher in the plasma of children with ASD compared to typical controls. We also found an association between the severity of behavior impairments in ASD children and altered immune responses as measured using the effector T cell responses and regulatory responses (using Teff/Treg ratios). Higher the Teff/Treg ratios, were associated with more severe problematic behavioral symptoms. Further, the potential biomarker relevance of Teff/Treg ratio was evaluated by the receiver operating characteristics curve. Data suggests that high TH1/Treg cell ratios could also be used as a potential marker for the diagnosis of children with ASD. Overall, our data suggest an imbalance in inflammatory and regulatory immune responses in ASD. Ratios of inflammatory/regulatory cells or cell frequencies such as Teff/Treg cells may be useful biomarkers for children with ASD with immune dysfunction.

Utility of Hypoglycemic Agents to Treat Asthma with Comorbid Obesity.

Adults with obesity may develop asthma that is ineffectively controlled by inhaled corticosteroids and long-acting beta-adrenoceptor agonists. Mechanistic and translational studies suggest that metabolic dysregulation that occurs with obesity, particularly hyperglycemia and insulin resistance, contributes to altered immune cell function and low-grade systemic inflammation. Importantly, in these cases, the same proinflammatory cytokines believed to contribute to insulin resistance may also be responsible for airway remodeling and hyperresponsiveness. In the past decade, new research has emerged assessing whether hypoglycemic therapies impact comorbid asthma as reflected by the incidence of asthma, asthma-related emergency department visits, asthma-related hospitalizations, and asthma-related exacerbations. The purpose of this review article is to discuss the mechanism of action, preclinical data, and existing clinical studies regarding the efficacy and safety of hypoglycemic therapies for adults with obesity and comorbid asthma.

A somatic hypermutation-based machine learning model stratifies individuals with Crohn's disease and controls.

Crohn's disease (CD) is a chronic relapsing-remitting inflammatory disorder of the gastrointestinal tract that is characterized by altered innate and adaptive immune function. Although massively parallel sequencing studies of the T cell receptor repertoire identified oligoclonal expansion of unique clones, much less is known about the B cell receptor (BCR) repertoire in CD. Here, we present a novel BCR repertoire sequencing data set from ileal biopsies from pediatric patients with CD and controls, and identify CD-specific somatic hypermutation (SHM) patterns, revealed by a machine learning (ML) algorithm trained on BCR repertoire sequences. Moreover, ML classification of a different data set from blood samples of adults with CD versus controls identified that V gene usage, clusters, or mutation frequencies yielded excellent results in classifying the disease (F1 > 90%). In summary, we show that an ML algorithm enables the classification of CD based on unique BCR repertoire features with high accuracy.

The Role of Non-Alcoholic Fatty Liver Disease in Infections.

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease, affecting one third of the Western population. The hallmark of the disease is excessive storage of fat in the liver. Most commonly, it is caused by metabolic syndrome (or one of its components). Even though the development of NAFLD has multiple effects on the human organism resulting in systemic chronic low-grade inflammation, this review is focused on NAFLD as a risk factor for the onset, progression, and outcomes of infectious diseases. The correlation between NAFLD and infections is still unclear. Multiple factors (obesity, chronic inflammation, altered immune system function, insulin resistance, altered intestinal microbiota, etc.) have been proposed to play a role in the development and progression of infections in people with NAFLD, although the exact mechanism and the interplay of mentioned factors is still mostly hypothesized. In this article we review only the selection of well-researched topics on NAFLD and infectious diseases (bacterial pneumonia, COVID, H. pylori, urinary tract infections, C. difficile, bacteremia, hepatitis B, hepatitis C, HIV, and periodontitis).