T Helper Research Articles

Infectious bronchitis virus vaccination, but not the presence of XCR1, is correlated with large differences in chicken caecal microbiota.

The chicken immune system and microbiota play vital roles in maintaining gut homeostasis and protecting against pathogens. In mammals, XCR1+ conventional dendritic cells (cDCs) are located in the gut-draining lymph nodes and play a major role in gut homeostasis. These cDCs sample antigens in the gut luminal contents and limit the inflammatory response to gut commensal microbes by generating appropriate regulatory and effector T-cell responses. We hypothesized that these cells play similar roles in sustaining gut homeostasis in chickens, and that chickens lacking XCR1 were likely to contain a dysbiotic caecal microbiota. Here we compare the caecal microbiota of chickens that were either heterozygous or homozygous XCR1 knockouts, that had or had not been vaccinated for infectious bronchitis virus (IBV). We used short-read (Illumina) and long-read (PacBio HiFi) metagenomic sequencing to reconstruct 670 high-quality, strain-level metagenome assembled genomes. We found no significant differences between alpha diversity or the abundance of specific microbial taxa between genotypes. However, IBV vaccination was found to correlate with significant differences in the richness and beta diversity of the microbiota, and to the abundance of 40 bacterial genera. In conclusion, we found that a lack of XCR1 was not correlated with significant changes in the chicken microbiota, but IBV vaccination was.

TRAF3 regulates STAT6 activation and T-helper cell differentiation by modulating the phosphatase PTP1B

The adaptor protein TNFR associated factor 3 (TRAF3) is a multifaceted regulator of lymphocyte biology that plays key roles in modulation of the molecular signals required for T cell activation and function. TRAF3 regulates signals mediated by the T cell receptor (TCR), costimulatory molecules, and cytokine receptors, which each drive activation of the serine/threonine kinase Akt. The impact of TRAF3 upon TCR/CD28-mediated activation of Akt, and thus on the diverse cellular processes regulated by Akt, including CD4 T cell fate decisions, remains poorly understood. We show here that TRAF3 deficiency led to impaired Akt activation, and thus to impaired in vitro skewing of CD4 T cells into the TH1 and TH2 fates. We investigated the role of TRAF3 in regulation of signaling pathways that drive TH1 and TH2 differentiation, and found that TRAF3 enhanced activation of Signal transducer and activator of transcription 6 (STAT6), thus promoting skewing toward the TH2 fate. TRAF3 promoted STAT6 activation by regulating recruitment of the inhibitory molecule Protein tyrosine phosphatase 1B (PTP1B) to the IL-4R signaling complex, in a manner that required integration of TCR/CD28- and IL-4R-mediated signals. This work reveals a new mechanism for TRAF3-mediated regulation of STAT6 activation in CD4 T cells, and adds to our understanding of the diverse roles played by TRAF3 as an important regulator of T cell biology.

In silico Identification of MHC Displayed Tumor Associated Peptides in Ovarian Cancer for Multi-Epitope Vaccine Construct.

Recognizing the potential of the immune system, immunotherapies have brought about a revolution in the treatment of cancer. Low tumour mutational burden and strong immunosuppression in the peritoneal tumor microenvironment (TME) lead to poor outcomes of immune checkpoint inhibition (ICI) and CART cell therapy in ovarian cancer. Alternative immunotherapeutic strategies are of utmost importance to achieve sound clinical success. The development of peptide vaccines based on tumor-associated antigens (TAAs) for ovarian cancer cells can be a potential target to provoke an anti-tumor immune response and subsequent clearance of tumour cells. The purpose of this in silico study was to find potential epitopes for a multi-epitope vaccine construct using the immunopeptidomics landscape of ovarian carcinoma. The four TAAs (MUC16, IDO1, FOLR1, and DDX5) were selected for potential epitopes prediction. The epitopes for B-cells, helper T-lymphocytes (HTL), and Cytotoxic Tlymphocytes (CTL) were predicted on the basis of antigenic, allergenic, and toxic properties. These epitopes were combined with suitable linkers and an adjuvant to form a multi-epitope construct. Four HTLs, 13 CTLs, and 6 potential B-cell epitopes were selected from the predicted epitope. The designed multi-epitope construct was potentially immunogenic, non-toxic, and non-allergenic. Physicochemical properties and higher-order structural analyses of the final construct revealed a potential vaccine candidate. The designed vaccine construct has the potential to trigger both humoral and cellular immune responses and may be employed as a therapeutic immunization candidate for ovarian malignancies. However, further in vitro and animal experimentation is required to establish the efficacy of the vaccine candidate.

Unraveling the origins of pathogenic CXCL13+ helper Tcells in systemic lupus erythematosus.

This Research Highlight discusses a recent publication, where the authors identified an increase in CXCL13+ peripheral helper T/follicular helper Tcells, which was concomitant with a decrease in CD96+ T helper 22 (TH22) cells in patients with systemic lupus erythematosus. The genetic and epigenetic cues that reciprocally regulate this pathogenic imbalance of T-cell subsets were also identified, thus providing targets for therapeutic intervention.

Identification of diagnostic markers and molecular clusters of cuproptosis-related genes in alcohol-related liver disease based on machine learning and experimental validation

Background and aimsAlcohol-related liver disease (ALD) is a worldwide burden. Cuproptosis has been shown to play a key role in the development of several diseases. However, the role and mechanisms of cuproptosis in ALD remain unclear. MethodsThe RNA-sequencing data of ALD liver samples were downloaded from the Gene Expression Omnibus (GEO) database. Bioinformatical analyses were performed using the R data package. We then identified key genes through multiple machine learning methods. Immunoinfiltration analyses were used to identify different immune cells in ALD patients and controls. The expression levels of key genes were further verified. ResultsWe identified three key cuproptosis-related genes (CRGs) (DPYD, SLC31A1, and DBT) through an in-depth analysis of two GEO datasets, including 28 ALD samples and eight control samples. The area under the curve (AUC) value of these three genes combined in determining ALD was 1.0. In the external datasets, the three key genes had AUC values as high as 1.0 and 0.917, respectively. Nomogram, decision curve, and calibration curve analyses also confirmed these genes’ ability to predict the diagnosis. These three key genes were found to be involved in multiple pathways associated with ALD progression. We confirmed the mRNA expression of these three key genes in mouse ALD liver samples. Regarding immune cell infiltration, the numbers of B cells, CD8 (+) T cells, NK cells, T-helper cells, and Th1 cells were significantly lower in ALD patient samples than in control liver samples. Single sample gene set enrichment analysis (ssGSEA) was then used to estimate the immune microenvironment of different CRG clusters and CRG-related gene clusters. In addition, we calculated CRG scores through principal component analysis (PCA) and selected Sankey plots to represent the correlation between CRG clusters, gene clusters, and CRG scores. Finally, the three key genes were confirmed in mouse ALD liver samples and liver cells treated with ethanol. ConclusionsWe first established a prognostic model for ALD based on 3 CRGs and robust prediction efficacy was confirmed. Our investigation contributes to a comprehensive understanding of the role of cuproptosis in ALD, presenting promising avenues for the exploration of therapeutic strategies.

Combined plasma protein and memory T cell profiling discern IBD-patient-immunotypes related to intestinal disease and treatment outcomes

Inflammatory bowel disease (IBD) chronicity results from memory T helper cell (Tmem) reactivation. Identifying patient-specific immunotypes is crucial for tailored treatment. We conducted a comprehensive study integrating circulating immune proteins and circulating Tmem, with intestinal tissue histology and mRNA analysis, in therapy-naïve pediatric IBD (Crohn’s disease, CD: n = 62; ulcerative colitis, UC: n = 20; age-matched controls n = 43), and after 10–12 weeks’ induction therapy. At diagnosis, plasma protein profiles unveiled two UC and three CD clusters with distinct disease courses. UC patients displayed unchanged circulating Tmem, while CD exhibited increased frequencies of gut-homing ex-Th17, known for high IFN-γ production. UC#2 had elevated Th17/neutrophil-pathway-related proteins and severe disease, with higher endoscopic and histological damage and Th17/neutrophil infiltration. Although both UC#1 and UC#2 responded to therapy, UC#2 required earlier immunomodulation. CD#3 had lower plasma protein concentrations, especially IFN-γ pathway proteins, fewer gut-homing ex-Th17 and clinically milder disease, confirmed by intestinal gene expression. CD#1 and CD#2 had comparably high Th1-related immune profiles, but CD#1 exhibited higher concentrations of proteins previously associated with poorer prognosis. Both CD clusters responded to induction therapy, with similar one-year outcomes. This study highlights feasibility of discriminating patient-specific immunotypes in IBD, advancing our understanding of immune pathogenesis, needed for tailored treatment strategies.

Machine learning-based cell death marker for predicting prognosis and identifying tumor immune microenvironment in prostate cancer

BackgroundProstate cancer (PCa) incidence and mortality rates are rising, necessitating precise prognostic tools to guide personalized treatment. Dysregulation of programmed cell death pathways in tumor suppression and cancer development has garnered increasing attention, providing a new research direction for identifying biomarkers and potential therapeutic targets. MethodsIntegrating multiple database resources, we constructed and optimized a prognostic signature based on the expression of programmed cell death-related genes (PCDRG) using ten machine learning algorithms. Model performance and prognostic effects were further evaluated. We analyzed the relationships between signature and clinicopathological features, somatic mutations, drug sensitivity, and the tumor immune microenvironment, and constructed a nomogram. The expression level of PCDRGs were evaluated and compared. ResultsOf 1560 PCDRGs, 149 were differentially expressed in PCa, with 34 associated with biochemical recurrence. The PCDRG-derived index (PCDI), constructed using the random forest algorithm, exhibited optimal prognostic performance, successfully stratifying PCa patients into two groups with significant prognostic differences. Patients with high PCDI scores exhibited poorer survival and lower immunotherapy benefit. PCDI was closely associated with the infiltration of specific immune cells, particularly positive correlations with macrophages and T helper cells, and negative correlations with neutrophils, suggesting that PCDI may influence the tumor immune microenvironment, thereby affecting patient prognosis and treatment response. PCDI was associated with age, pathological stage, somatic mutations, and drug sensitivity. The PCDI-based nomogram demonstrated excellent performance in predicting biochemical recurrence in PCa patients. Finally, the differential expression of these PCDRGs was verified based on cell lines and PCa patient expression profile data. ConclusionThis study developed an effective prognostic indicator for prostate cancer, PCDI, using machine learning approaches. PCDI reflects the link between aberrant programmed cell death pathways and disease progression and treatment response.

The diagnostic value and associated molecular mechanism study for fibroblast-related mitochondrial genes on keloid.

This study aims to reveal the mechanism of fibroblast-related mitochondrial genes on keloid formation and explore promising signature genes for keloid diagnosis. The distribution of fibroblasts between the keloid sample and control sample based on three keloid datasets, followed by the differentially expressed genes (DEGs) investigation and associated enrichment analysis. Then, hub genes were explored based on DEGs, mitochondrial genes from an online database, as well as fibroblast-related genes that were revealed by WCGNA. Subsequently, signature genes were screened through machine learning, and their diagnostic value was validated by nomogram. Moreover, the targeted drugs and related transcriptional regulation of these genes were analyzed. Finally, the verification analysis was performed on signature genes using qPCR analysis. A total of totally 329 DEGs were revealed based on three datasets, followed by enrichment analysis. WGCNA revealed a total of 258 fibroblast-related genes, which were primarily assembled in functions like muscle tissue development. By using machine learning, we screened four signature genes (ACSF2, ALDH1B1, OCIAD2, and SIRT4) based on eight hub genes (fibroblast-related mitochondrial genes). Nomogram and validation analyses confirmed the well-diagnostic performance of these four genes in keloid. Immune infiltration and drug correlation analyses showed that SIRT4 was significantly associated with immune cell type 2 T helper cells and molecular drug cyclosporin. All these findings provided new perspectives for the clinical diagnosis and therapy of keloid. The fibroblast-related mitochondrial genes including SIRT4, OCIAD2, ALDH1B1, and ACSF2 were novel signature genes for keloid diagnosis, offering novel targets and strategies for diagnosis and therapy of keloid.

ценка риска формирования у детей вторичного иммунодефицита в условиях контаминации биосред алюминием и полиморфизма гена клеточной гибели FAS rs1159120 и антигенраспознающего гена толл-подобного рецептора TLR4 rs1927911

Secondary immunodeficiency remains an incompletely understood medical problem, and despite a significant number of international and scientific studies, there is no complete picture of the causes and consequences of this pathology. Metal cations have been proven to participate in the formation of acquired immunodeficiency. In particular, aluminum properties as an immune suppressor have been established and its targets in the body have been identified in case aluminum was present in biological media. However, no evaluations have been accomplished so far as regards the role of specific point genetic changes, that is, polymorphisms in the genes of immune system compartments that determine the risk of negative effects caused by contamination with metal cations, including aluminum. It is quite relevant to search and substantiate immunogenetic markers to create an indicator system for diagnostics and prevention of secondary immunodeficiency states in children associated with aluminum contamination in biological media. We examined 97 preschool children exposed to elevated levels of airborne aluminum (in an area influenced by a metallurgic production). The study groups were divided depending on either presence or absence of secondary immunodeficiency as immune system pathology (common variable immunodeficiency D83). Several markers of the immune system were evaluated: aluminum-specific IgG, CD3+, CD4+, CD8+, CD127-, CD95+, CD284+, and phagocytic activity; we also evaluated polymorphism of TLR4 A8595G (rs1927911) and FAS C14405T (rs1159120) genes of innate and acquired immunity. According to the results obtained by examining biological media composition, children with secondary immunodeficiency had 1.8 times higher aluminum levels in urine (0.0095 ± 0.0014 vs. 0.0054 ± 0.0009 mg/dm3, reference range < 0.0075 mg/dm3) as opposed to their conditionally healthy peers. We established an authentic inverse dependence between the expression level of the main CD clusters (CD3+: r = -0.38; CD4+: r = -0.39; CD8+: r = -0.26) as well as indicators of phagocytic activity (r = -0.22–0.23) and the level of aluminum contamination in biological media (urine). Expression of T-mature lymphocyte clusters was found to be inhibited by 1.3–3.1 times (including T-helper, effector T-lymphocytes, NK-killers, regulatory lymphocytes) and we also detected some changes in expression of specific immunoglobulin of IgG class to aluminum. All this results in an unacceptable level of relative risk (RR = 1.23–1.63) of developing secondary immunodeficiency against increased frequency of allele C and genotype CC of FAS gene (rs1159120) by 1.2 and 1.5 times respectively, as well as minor allele G of TLR4 gene (rs1927911) by 1.8 times relative to the comparison group (OR = 4.05; CI: 1.41–11.59; p = 0.006; RR = 1.23; CI: 1.02–1.48) and (OR = 2.01; CI: 1.04–3.91; p = 0.037; RR = 1.64; CI:1.46–1.94). Toll-dependent and FAS-dependent mechanism of this risk is associated with aluminum contamination. It is recommended to use a combination of immune and genetic markers as indicator ones when evaluating the immune system state, in order to prevent the risk (RR = 1.23–1.63) of secondary immunodeficiency associated with aluminum contamination in biological media.

Assessing risks of secondary immunodeficiency in children with aluminum contamination in biological media and polymorphism of the cell death gene FAS rs1159120 and the antigen-recognizing gene of the toll-like receptor TLR4 rs1927911

Secondary immunodeficiency remains an incompletely understood medical problem, and despite a significant number of international and scientific studies, there is no complete picture of the causes and consequences of this pathology. Metal cations have been proven to participate in the formation of acquired immunodeficiency. In particular, aluminum properties as an immune suppressor have been established and its targets in the body have been identified in case aluminum was present in biological media. However, no evaluations have been accomplished so far as regards the role of specific point genetic changes, that is, polymorphisms in the genes of immune system compartments that determine the risk of negative effects caused by contamination with metal cations, including aluminum. It is quite relevant to search and substantiate immunogenetic markers to create an indicator system for diagnostics and prevention of secondary immunodeficiency states in children associated with aluminum contamination in biological media. We examined 97 preschool children exposed to elevated levels of airborne aluminum (in an area influenced by a metallurgic production). The study groups were divided depending on either presence or absence of secondary immunodeficiency as immune system pathology (common variable immunodeficiency D83). Several markers of the immune system were evaluated: aluminum-specific IgG, CD3+, CD4+, CD8+, CD127-, CD95+, CD284+, and phagocytic activity; we also evaluated polymorphism of TLR4 A8595G (rs1927911) and FAS C14405T (rs1159120) genes of innate and acquired immunity. According to the results obtained by examining biological media composition, children with secondary immunodeficiency had 1.8 times higher aluminum levels in urine (0.0095 ± 0.0014 vs. 0.0054 ± 0.0009 mg/dm3, reference range < 0.0075 mg/dm3) as opposed to their conditionally healthy peers. We established an authentic inverse dependence between the expression level of the main CD clusters (CD3+: r = -0.38; CD4+: r = -0.39; CD8+: r = -0.26) as well as indicators of phagocytic activity (r = -0.22–0.23) and the level of aluminum contamination in biological media (urine). Expression of T-mature lymphocyte clusters was found to be inhibited by 1.3–3.1 times (including T-helper, effector T-lymphocytes, NK-killers, regulatory lymphocytes) and we also detected some changes in expression of specific immunoglobulin of IgG class to aluminum. All this results in an unacceptable level of relative risk (RR = 1.23–1.63) of developing secondary immunodeficiency against increased frequency of allele C and genotype CC of FAS gene (rs1159120) by 1.2 and 1.5 times respectively, as well as minor allele G of TLR4 gene (rs1927911) by 1.8 times relative to the comparison group (OR = 4.05; CI: 1.41–11.59; p = 0.006; RR = 1.23; CI: 1.02–1.48) and (OR = 2.01; CI: 1.04–3.91; p = 0.037; RR = 1.64; CI:1.46–1.94). Toll-dependent and FAS-dependent mechanism of this risk is associated with aluminum contamination. It is recommended to use a combination of immune and genetic markers as indicator ones when evaluating the immune system state, in order to prevent the risk (RR = 1.23–1.63) of secondary immunodeficiency associated with aluminum contamination in biological media.

Comparison of antigen-specific B cell responses reveals disparity in immunogenicity and memory B cell formation across COVID-19 vaccine platforms

Various vaccine technologies have been employed in the coronavirus disease 2019 (COVID-19) vaccines, including whole inactivated virus (WIV), recombinant protein, mRNA, and nanoparticle vaccines. To elucidate the cellular mechanisms underlying the immune responses elicited by different vaccines, we examined and compared antigen-specific B cell responses targeting the receptor-binding domain (RBD) of the viral spike protein. We found that the nanoparticle vaccine pathogen-like antigens-RBD (PLA-RBD) and the mRNA vaccine demonstrated superior immunogenicity compared with the WIV vaccine and the RBD-dimer, a recombinant protein vaccine. Interestingly, the WIV vaccine contains toll-like receptor ligands that enhance IgG2a/c class-switching. For the mRNA vaccine, although it induces robust germinal center responses and T follicular helper (Tfh) cells, it has limited ability to induce memory B cells and long-lived plasma cells. These results indicate that vaccine formats significantly influence both the quantity and quality of immune responses, providing valuable insights for the future development of vaccines.

T-Cell Senescence in Human Metabolic Diseases.

Immunosenescence denotes a state of dysregulated immune cell function characterized by a confluence of factors, including arrested cell cycle, telomere shortening, markers of cellular stress, mitochondrial dysfunction, loss of proteostasis, epigenetic reprogramming, and secretion of proinflammatory mediators. This state primarily manifests during the aging process but can also be induced in various pathological conditions, encompassing chronic viral infections, autoimmune diseases, and metabolic disorders. Age-associated immune system alterations extend to innate and adaptive immune cells, with T-cells exhibiting heightened susceptibility to immunosenescence. In particular, senescent T-cells have been identified in the context of metabolic disorders such as obesity, diabetes, and cardiovascular diseases. Recent investigations suggest a direct link between T-cell senescence, inflammation, and insulin resistance. The perturbation of biological homeostasis by senescent T-cells appears intricately linked to the initiation and progression of metabolic diseases, particularly through inflammation-mediated insulin resistance. Consequently, senescent T-cells are emerging as a noteworthy therapeutic target. This review aims to elucidate the intricate relationship between metabolic diseases and T-cell senescence, providing insights into the potential roles of senescent T-cells in the pathogenesis of metabolic disorders. Through a comprehensive examination of current research findings, this review seeks to contribute to a deeper understanding of the complex interplay between immunosenescence and metabolic health.

The Use of Flow Cytometry in the Analysis of Sows’ Colostrum and Milk

Abstract The flow cytometry method is used in many fields, not only scientific, but also clinical. In science, flow cytometry is used in immunology, molecular biology, microbiology or plant biology. In medicine, has its use, in the diagnosis of tumours, in reproductive and prenatal diagnosis, in transplants or in haematology. In our experimental work, we used this method to analyse colostrum and milk of sows. The aim of this study was to determine the number of somatic cells, the number of leukocytes and the number of T-lymphocytes. Colostrum samples were collected within 24 hours of delivery and then milk samples were collected at weekly intervals during 3 weeks. Statistical analysis revealed significant differences in the number of leukocytes (CD45+) in colostrum and milk. The most significant difference was noted between colostrum and milk in weeks 2 and 3 of the experiment (P < 0.0001), with the highest values found in colostrum. On the other hand, we found that the levels of helper T-cells (CD4+) and cytotoxic T-cells (CD8+) gradually increased over time (P > 0.05), with the highest values observed in the third week after farrowing. We can conclude that flow cytometry can be successfully used for the examination of somatic cells in sows’ milk.

Plasmodium berghei HMGB1 controls the host immune responses and splenic clearance by regulating the expression of pir genes

High mobility group box (HMGB) proteins belong to high mobility group (HMG) superfamily of non-histone nuclear proteins that are involved in chromatin remodeling, regulation of gene expression and DNA repair. When extracellular, HMGBs serve as alarmins inducing inflammation and this is attributed to the proinflammatory activity of box B. Here, we show that Plasmodium HMGB1 has key amino acid changes in box B resulting in the loss of TNF-α stimulatory activity. Site-directed mutagenesis of the critical amino acids in box B with respect to mouse HMGB1 renders recombinant Plasmodium berghei (Pb) HMGB1 capable of inducing TNF-α release. Targeted deletion of PbHMGB1 and a detailed in vivo phenotyping show that PbHMGB1 knockout (KO) parasites can undergo asexual stage development. Interestingly, Balb/c mice-infected with PbHMGB1KO parasites display a protective phenotype with subsequent clearance of blood parasitemia, and develop long-lasting protective immunity against the challenges performed with Pb wildtype parasites. The characterization of splenic responses show prominent germinal centres leading to effective humoral responses and enhanced T follicular helper cells. There is also a complete protection from experimental cerebral malaria in CBA/CaJ mice susceptible for cerebral pathogenesis with subsequent parasite clearance. Transcriptomic studies suggest the involvement of PbHMGB1 in pir expression. Our findings highlight the gene regulatory function of parasite HMGB1 and its in vivo significance in modulating the host immune responses. Further, clearance of asexual stages in PbHMGB1KO-infected mice underscores the important role of parasite HMGB1 in host immune evasion. These findings have implications in developing attenuated blood-stage vaccine for malaria.

225.6: Targeting BCL6-mediated responses to inhibit allogeneic T follicular helper cell functions.

225.6: Targeting BCL6-mediated responses to inhibit allogeneic T follicular helper cell functions.

Generation of antigen-specific memory CD4 T cells by heterologous immunization enhances the magnitude of the germinal center response upon influenza infection.

Current influenza vaccine strategies have yet to overcome significant obstacles, including rapid antigenic drift of seasonal influenza viruses, in generating efficacious long-term humoral immunity. Due to the necessity of germinal center formation in generating long-lived high affinity antibodies, the germinal center has increasingly become a target for the development of novel or improvement of less-efficacious vaccines. However, there remains a major gap in current influenza research to effectively target T follicular helper cells during vaccination to alter the germinal center reaction. In this study, we used a heterologous infection or immunization priming strategy to seed an antigen-specific memory CD4+ T cell pool prior to influenza infection in mice to evaluate the effect of recalled memory T follicular helper cells in increased help to influenza-specific primary B cells and enhanced generation of neutralizing antibodies. We found that heterologous priming with intranasal infection with acute lymphocytic choriomeningitis virus (LCMV) or intramuscular immunization with adjuvanted recombinant LCMV glycoprotein induced increased antigen-specific effector CD4+ T and B cellular responses following infection with a recombinant influenza strain that expresses LCMV glycoprotein. Heterologously primed mice had increased expansion of secondary Th1 and Tfh cell subsets, including increased CD4+ TRM cells in the lung. However, the early enhancement of the germinal center cellular response following influenza infection did not impact influenza-specific antibody generation or B cell repertoires compared to primary influenza infection. Overall, our study suggests that while heterologous infection or immunization priming of CD4+ T cells is able to enhance the early germinal center reaction, further studies to understand how to target the germinal center and CD4+ T cells specifically to increase long-lived antiviral humoral immunity are needed.

Indirubin induces tolerogenic dendritic cells via aryl hydrocarbon receptor activation and ameliorates allergic asthma in a murine model by expanding Foxp3-expressing regulatory T cells

BackgroundAllergic asthma is a chronic bronchial inflammatory disease closely associated with abnormal immune responses of dendritic cells (DCs) and allergen-specific type 2 T helper (Th2) cells. Indirubin (IR), a natural aryl hydrocarbon receptor (AhR) ligand, exerts anti-inflammatory and immunomodulatory properties. PurposeIn this study, we aimed to clarify whether IR exhibits immunomodulatory action on DCs via AhR activation and investigated the antiallergic effects of IR in a mouse model of allergic asthma. MethodsLipopolysaccharide (LPS)-activated bone marrow-derived DCs were treated with IR. Their mRNA expressions, cytokine production, and phenotype patterns were determined by a quantitative real-time PCR, ELISA, flow cytometry, and RNA sequencing. The mixed lymphocyte reaction was utilized to evaluate the regulatory function of IR-treated DCs on T-cell differentiation. Moreover, mice with ovalbumin (OVA)-induced allergic asthma were treated with IR. Thereafter, the airway hyperresponsiveness (AHR), allergen-specific IgE production, cytokine levels, airway inflammation, and T-cell responses were evaluated. ResultsTreatment of LPS-stimulated DCs with 20 μM IR significantly reduced IL-12 and TNF-α production while increasing IL-10 secretion. Meanwhile, these DCs expressed decreased levels of CD80 but increased levels of Jagged 1 surface molecules. However, the effects of IR on DCs were reversed by pretreatment with the AhR antagonist, CH223191. Additionally, the coculture of these tolerogenic-like DCs with allogeneic CD4+T cells promoted the generation of Foxp3+ regulatory T (Treg) cells. A transcriptomic analysis identified several downregulated genes that are involved in regulating cell migration, cytokine secretion, and inflammatory responses in DCs after IR treatment. In an asthmatic murine model, oral administration of 25 mg kg-1 body weight of IR efficiently alleviated the development of AHR, OVA-specific IgE production, and levels of Th2-type cytokines (IL-4, IL-5, and IL-13) and the CCL11 chemokine. IR treatment also attenuated inflammatory cell recruitment and mucus production in the lungs. Notably, an enhanced frequency of Foxp3+ Treg cells and reduced effector T-cell proliferation associated with increased levels of IL-10 and TGF-β were observed in IR-treated mice. ConclusionIR can induce tolerogenic-like BMDCs which promote the differentiation of Treg cells. Importantly, the expansion of Foxp3+ Treg cells contributed to the therapeutic efficacy of IR against allergic asthma.

Surface Immune Checkpoints as Potential Biomarkers in Physiological Pregnancy and Recurrent Pregnancy Loss.

Due to the genetic diversity between the mother and the fetus, heightened control over the immune system during pregnancy is crucial. Immunological parameters determined by clinicians in women with idiopathic recurrent spontaneous abortion (RSA) include the quantity and activity of Natural Killer (NK) and Natural Killer T (NKT) cells, the quantity of regulatory T lymphocytes, and the ratio of pro-inflammatory cytokines, which indicate imbalances in Th1 and Th2 cell response. The processes are controlled by immune checkpoint proteins (ICPs) expressed on the surface of immune cells. We aim to investigate differences in the expression of ICPs on T cells, T regulatory lymphocytes, NK cells, and NKT cells in peripheral blood samples collected from RSA women, pregnant women, and healthy multiparous women. We aim to discover new insights into the role of ICPs involved in recurrent pregnancy loss. Peripheral blood mononuclear cells (PBMCs) were isolated by gradient centrifugation from blood samples obtained from 10 multiparous women, 20 pregnant women (11-14th week of pregnancy), and 20 RSA women, at maximum of 72 h after miscarriage. The PBMCs were stained for flow cytometry analysis. Standard flow cytometry immunophenotyping of PBMCs was performed using antibodies against classical lymphocyte markers, including CD3, CD4, CD8, CD56, CD25, and CD127. Additionally, ICPs were investigated using antibodies against Programmed Death Protein-1 (PD-1, CD279), T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3, CD366), V-domain Ig suppressor of T cell activation (VISTA), T cell immunoglobulin and ITIM domain (TIGIT), and Lymphocyte activation gene 3 (LAG-3). We observed differences in the surface expression of ICPs in the analyzed subpopulations of lymphocytes between early pregnancy and RSA, after miscarriage, and in women. We noted diminished expression of PD-1 on T lymphocytes (p = 0.0046), T helper cells (CD3CD4 positive cells, p = 0.0165), T cytotoxic cells (CD3CD8 positive cells, p = 0.0046), T regulatory lymphocytes (CD3CD4CD25CD127 low positive cells, p = 0.0106), and NKT cells (CD3CD56/CD16 positive cells, p = 0.0438), as well as LAG-3 on lymphocytes T (p = 0.0225) T helper, p = 0.0426), T cytotoxic cells (p = 0.0458) and Treg (p = 0.0293), and cells from RSA women. Impaired expression of TIM-3 (p = 0.0226) and VISTA (p = 0.0039) on CD8 cytotoxic T and NK (TIM3 p = 0.0482; VISTA p = 0.0118) cells was shown, with an accompanying increased expression of TIGIT (p = 0.0211) on NKT cells. The changes in the expression of surface immune checkpoints indicate their involvement in the regulation of pregnancy. The data might be utilized to develop specific therapies for RSA women based on the modulation of ICP expression.

Inhibiting the expression of spindle appendix cooled coil protein 1 can suppress tumor cell growth and metastasis and is associated with cancer immune cells in esophageal squamous cell carcinoma.

Inhibiting the expression of spindle appendix cooled coil protein 1 (SPDL1) can slow down disease progression and is related to poor prognosis in patients with esophageal cancer. However, the specific roles and molecular mechanisms of SPDL1 in esophageal squamous cell carcinoma (ESCC) have not been explored yet. The current study aimed to investigate the expression levels of SPDL1 in ESCC via transcriptome analysis using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases. Moreover, the biological roles, molecular mechanisms, and protein networks involved in SPDL1 were identified using machine learning and bioinformatics. The cell counting kit-8 assay, EdU staining, and transwell assay were used to investigate the effects of inhibiting SPDL1 expression on ESCC cell proliferation, migration, and invasion. Finally, the correlation between the SPDL1 expression and cancer immune infiltrating cells was evaluated by analyzing data from the TCGA database. Results showed that SPDL1 was overexpressed in the ESCC tissues. The SPDL1 expression was related to age in patients with ESCC. The SPDL1 co-expressed genes included those involved in cell division, cell cycle, DNA repair and replication, cell aging, and other processes. The high-risk scores of SPDL1-related long non-coding RNAs were significantly correlated with overall survival and cancer progression in patients with ESCC (P < 0.05). Inhibiting the SPDL1 expression was effective in suppressing the proliferation, migration, and invasion of ESCC TE-1 cells (P < 0.05). The overexpression of SPDL1 was positively correlated with the levels of Th2 and T-helper cells, and was negatively correlated with the levels of plasmacytoid dendritic cells and mast cells. In conclusion, SPDL1 was overexpressed in ESCC and was associated with immune cells. Further, inhibiting the SPDL1 expression could effectively slow down cancer cell growth and migration. SPDL1 is a promising biomarker for treating patients with ESCC.

Expansion of T follicular helper cells is associated with disease progression in rat experimental membranous nephropathy model.

T follicular helper (Tfh) cells drive humoral immunity by facilitating B cell responses, but the functional role of Tfh cells in the pathogenesis of idiopathic membranous nephropathy (IMN) remains unclear. This study aimed to establish a rat experimental membranous nephropathy model, investigate the phenotypic characteristics of Tfh cells, and analyze a clinically significant correlation between Tfh cells. Passive Heymann nephritis (PHN) rats were induced by immunizing Sprague Dawley rats with anti-Fx1A serum. The frequency of Tfh and B cell subsets was analyzed with flow cytometry (FC). The serum concentration of interleukin-21 (IL-21), the relative mRNA expression levels of IL-21 and B cell lymphoma 6 (Bcl-6) in spleen mononuclear cells (MNCs), and the kidney infiltration of CD4+ T cells and IL-21 were assessed. The potential correlations among these measures were analyzed. In comparison with the control group, significantly increased percentages of Tfh cells, inducible T cell co-stimulator-positive (ICOS+) Tfh cells, and mRNA expression of Bcl-6 were detected in the spleen of PHN rats. Elevated IL-21 expression was detected in the serum and kidneys. Remarkably, the percentage of splenic ICOS+ Tfh cells was positively correlated with 24 h urine protein concentrations (r = 0.676, p = 0.011) in PHN rats. These data indicate that ICOS+ Tfh cells contribute to development of IMN, and they might be potential therapeutic targets for IMN.