T Helper Research Articles

Возрастная динамика субпопуляций Т-лимфоцитов у пациентов с синдромом делеции 22q11.2 (синдромом Ди Джорджи)

Patients with the 22q11.2 deletion syndrome (DiGeorge syndrome, DDS) suffer from T-cell lymphopenia, changes in function and subpopulation of T-lymphocytes. The bibliographical data conflicts on the characteristics of T-lymphocytes in patients with DDS and their changes during physiological maturation. The purpose of this research was to follow-up patients with emphasis on the dynamics of changes in T-lymphocyte subpopulations with age. Methods used: 117 patients observed during 2013-2023 who were administered at the Allergology and Immunology Department with the G.N. Speransky City Children’s Hospital No. 9 (Moscow, Russia) with a diagnosis of DDS and who had undergone blood sampling to assess T-lymphocyte subpopulations using flow cytometry. All patients (0 to 18 y/o) were divided into 4 age groups: 0 to 2 y/o, 2 to 5 y/o, 5 to 10 y/o and 10 to 18 y/o. In parallel, the blood samples of 185 apparently healthy children of the corresponding age were examined. Results: a decrease in CD3 T-lymphocytes, CD4 T-helper cells, CD8 T-cytotoxic lymphocytes, CD4 early thymic emigrants and CD4 naive T-lymphocytes was found in all age groups (p<0.05). CD8+ naive T-lymphocytes and CD8+ early thymic emigrants were reduced in all age groups, but in the 2 to 5 y/o age group their values were close to normal (p=0.072 and p=0.220, respectively). CD4+ central memory cells were elevated in all age groups (p<0.001), while CD8+ central memory cells, CD4+ and CD8+ effector memory cells differed in that they had normal values in the 2 to 5 y/o age group (p=0.229, p=0.457 and p=0.140, respectively). CD4+ TEMRA were significantly increased in the 0 to 2 y/o age group (p=0.002), and in older age groups they tended to normal values. CD8+ TEMRA did not differ from the control group and did not have age-related dynamics. The T-helper subpopulations were characterized by a significant increase in the percentage of T-helper type 1, T-helper 17, T-helper 17.1 and a decrease in T-helper type 2 compared to the population of healthy blood sample donors (p=0.001), except for patients from the 2 to 5 y/o age group. T-regulatory cells in absolute amount were reduced in all age groups (p<0.001), while their relative number corresponded to the norm in the 0 to 2 y/o age group (p=0.811) and decreased slightly in patients in older age groups, especially in the 2 to 5 y/o age group (p=0.030). Conclusion: the pathology of thymus development in patients with DDS leads to impaired maturation of T-lymphocytes, leading to an increase in the number of mature forms of T-lymphocytes, shifts towards the development of T-helper 1 and T-helper 17, and a decrease in T-regulatory cells. Disturbances in T-lymphocytes can cause changes (dysregulation) in subpopulations of B-cells. All these processes may underlie the progression of autoimmune and infectious complications in such patients that are increasing with aging.

Immune profiling and functional analysis of NK and T cells in ataxia telangiectasia.

Ataxia telangiectasia (AT) is a rare autosomal-recessive disorder characterized by profound neurodegeneration, combined immunodeficiency, and an increased risk for malignant diseases. Treatment options for AT are limited, and the long-term survival prognosis for patients remains grim, primarily due to the emergence of chronic respiratory pathologies, malignancies, and neurological complications. Understanding the dysregulation of the immune system in AT is fundamental for the development of novel treatment strategies. In this context, we performed a retrospective longitudinal immunemonitoring of lymphocyte subset distribution in a cohort of AT patients (n = 65). Furthermore, we performed FACS analyses of peripheral blood mononuclear cells from a subgroup of 12 AT patients to examine NK and T cells for the expression of activating and functional markers. We observed reduced levels of peripheral blood CD3+CD8+ cytotoxic T cells, CD3+CD4+ T helper cells, and CD19+ B cells, whereas the amount of CD3--CD56+ NK cells and CD3+CD56+ NKT-like cells was similar compared with age-matched controls. Notably, there was no association between the age-dependent kinetic of T-, B-, or NK-cell counts and the occurrence of malignancy in AT patients. Additionally, our results indicate an altered NK- and T-cell response to cytokine stimulation in AT with increased levels of TRAIL, FasL, and CD16 expression in NK cells, as well as an elevated activation level of T cells in AT with notably higher expression levels of IFN-γ, CD107a, TRAIL, and FasL. Together, these findings imply function alterations in AT lymphocytes, specifically in T and NK cells, shedding light on potential pathways for innovative therapies.

Epigenetic agents plus anti-PD-1 reprogram the tumor microenvironment and restore antitumor efficacy in Hodgkin lymphoma

AbstractDNA methyltransferase inhibitor decitabine plus anti–programmed cell death 1 (DP) therapy was effective in relapsed/refractory classic Hodgkin lymphoma (cHL). However, a subset of patients experienced primary resistance or relapse/progression after DP therapy. In this study, we evaluated the efficacy and safety of a triplet regimen consisting of the histone deacetylase inhibitor chidamide, decitabine, and anti–PD-1 camrelizumab (CDP) in 52 patients who previously received DP therapy. CDP treatment was well tolerated and resulted in an objective response rate of 94% (95% confidence interval [CI], 84-99), with 50% (95% CI, 36-64) of patients achieving complete response (CR). Notably, all patients who were recalcitrant to previous DP treatment exhibited therapeutic responses after CDP therapy, although their CR rate was lower than patients responsive to prior DP. Overall, the median progression-free survival was 29.4 months. Through single-cell RNA sequencing of pretreatment and on-treatment cHL tumor biopsy samples, we observed the heterogeneity of rare malignant Hodgkin Reed/Sternberg (HRS)–like cells. The classical CD30+ HRS-like cells interacted with abundant immunosuppressive IL21+CD4+ T helper cells, forming a positive feedback loop that supported their survival. While the CD30– HRS-like cell population showed potential resistance to anti–PD-1 immunotherapy. CDP treatment promoted the activation of diverse tumor-reactive CD8+ T cells and suppressed the proliferation of IL21+CD4+ T cells by inhibiting STAT1/3 signaling, thereby alleviating their immunosuppressive effects. These findings provide insights into the cHL microenvironment that contributes to anti–PD-1 resistance and highlight the therapeutic effectiveness of dual epi-immunotherapy in overcoming immunotherapy resistance. This trial was registered at www.clinicaltrials.gov as #NCT04233294.

Insights into preeclampsia: a bioinformatics approach to deciphering genetic and immune contributions.

Preeclampsia (PE) is a global pregnancy concern, characterized by hypertension with an unclear etiology. This study employs Mendelian randomization (MR) and single-cell RNA sequencing (scRNA-seq) to clarify its genetic and molecular roots, offering insights into diagnosis and treatment avenues. We integrated PE-specific genome-wide association study (GWAS) data, expression and protein quantitative trait loci (eQTL and pQTL) data, and single-cell data from peripheral blood mononuclear cells (PBMCs). We identified highly variable genes using single-cell information and employed MR to determine potential causality. We also combined pQTL and GWAS data, discerned genes positively associated with PE through scRNA-seq, and leveraged the Enrichr platform to unearth drug-gene interactions. Our scRNA-seq pinpointed notable cell type distribution variances, especially in T helper cells (Th cells), between PE and control groups. We unveiled 591 highly variable genes and 6 directly PE-associated genes. Although MR revealed correlations with PE risk, pQTL analysis was inconclusive due to data constraints. Using DSigDB, 93 potential therapeutic agents, like Retinoic acid targeting core genes (IFITM3, NINJ1, COTL1, CD69, and YWHAZ), emerged as prospective multi-target treatments. Utilizing MR and scRNA-seq, this study underscores significant cellular disparities, particularly in Th cells, and identifies crucial genes related to PE. Despite some limitations, these genes have been revealed in PE's underlying mechanism. Potential therapeutic agents, such as Retinoic acid, suggest promising treatment pathways.

Towards an optimized model of food allergy in zebrafish

BackgroundThe prevalence of food allergies is on the rise, posing a significant challenge to public health. Rodents serve as the predominant animal model in food allergy research; yet, the application of rodent models proves to be a laborious and time-consuming endeavor. It is imperative to develop novel in vivo models. MethodsOvalbumin (OVA) was administered as the allergen, following the recommended dosage used in other species. During the sensitization phase, a dosage of 0.25 mg per 10 tails per 1 L was administered twice daily, and during the challenge phase, the dosage was increased to 3 times the initial level. The study explored two dimensions of sensitization: the mode of exposure, which can be either continuous or intermittent, and the duration of exposure, which includes 3 days, 5 days, and 7 days. We examined midgut pathological changes, immunoglobulins contents, and mRNA expressions associated to T helper cells (Th) 2 cytokines following exposure. ResultsA significant 109.3 % increase in the number of eosinophils was observed in the midgut histopathology following intermittent 5-day OVA exposure, which emerged as the most effective model. OVA exposure increased concentrations of immunoglobulin M (IgM) (105.2 %), IgZ (312.1 %), and IgD (304.3 %) in this model. The mRNA expressions of Th2-related interleukin (IL)-4 and IL-13 were also elevated by 132.8 % and 421.0 %, respectively. ConclusionThe intermittent 5-day OVA exposure was suggested to be the best constructed zebrafish food allergy model, which may be a potential tool for research into food allergies.

Characterizing Relationships between T-cell Inflammation and Outcomes in Patients with High-Risk Neuroblastoma According to Mesenchymal and Adrenergic Signatures.

Adrenergic (ADRN) and mesenchymal (MES) lineages are distinct biologic cell types in neuroblastoma. We defined ADRN and MES specific genes and found that high-risk, ADRN tumors harboring elevated T-cell inflammation signatures had superior overall survival. Our findings bolster support for further developing immunotherapy-based approaches for children with high-risk neuroblastoma.

Simultaneous distinct cutaneous fungal infections with chromoblastomycosis due to Exophiala xenobiotica and hyalohyphomycosis due to Scedosporium apiospermum in a patient with severe cellular immunodeficiency.

Deep-seated dermatomycosis is a rare disease that is often caused by trauma and/or systemic immunodeficiency. We describe a case of chromoblastomycosis complicated by hyalohyphomycosis that occurred simultaneously at different sites. A 92-year-old Japanese man who had been taking oral prednisolone for an IgG4-related respiratory disease visited our clinic. He developed brownish plaques with grayish-white scales with pseudo-carcinomatous hyperplasia and numerous brownish muriform cells developing in the dermis of his right hand, and multiple painful abscesses with pustules and papules and numerous hyphae within and around the histiocytes in the dermis of his right lower leg. Upon skin tissue culture and DNA sequencing, Exophiala xenobiotica and Scedosporium apiospermum were detected separately. He had severe cellular immunodeficiency indicated by low levels in the phytohemagglutinin (PHA)-stimulated lymphocyte transformation test (LTT) and serum interferon-gamma (IFN-γ), although his humoral immunity was normal. The patient died of bacterial pneumonia, despite antifungal drug treatment for 2 months. IFN-γ producing type 1 T helper (Th1) cells play an important role in the defense against fungal infections, however, corticosteroids specifically suppress Th1 cell responses and promote the induction of fungal infection. Measurement of PHA-stimulated LTT and serum IFN-γ may be useful in determining the severity and prognosis of deep-seated dermatomycosis in patients undergoing corticosteroid treatment.

Irreversible electroporation of localised prostate cancerdownregulates immune suppression andinduces systemic anti-tumour T-cell activation - IRE-IMMUNO study.

To prospectively compare systemic anti-tumour immune responses induced by irreversible electroporation (IRE) and robot-assisted radical prostatectomy (RARP) in patients with localised intermediate-risk prostate cancer (PCa). Between February 2021 and June 2022, before and after treatment (at 5, 14 and 30 days) peripheral blood samples of 30 patients with localised PCa were prospectively collected. Patient inclusion criteria were: International Society of Urological Pathologists Grade 2-3, clinical cancer stage ≤T2c, prostate-specific antigen level <20 ng/mL). Patients were treated with IRE (n = 20) or RARP (n = 10). Frequency and activation status of lymphocytic and myeloid immune cell subsets were determined using flow cytometry. PCa-specific T-cell responses to prostatic acid phosphatase(PSAP) and cancer testis antigen (New York oesophageal squamous cell carcinoma 1 [NY-ESO-1]) were determined by interferon-γ enzyme-linked immunospot assay (ELISpot). Repeated-measures analysis of variance and two-sided Student's t-tests were used to compare immune responses over time and between treatment cohorts. Patient and tumour characteristics were similar between the cohorts except for age (median 68 years [IRE] and 62 years [RARP], P = 0.01). IRE induced depletion of systemic regulatory Tcells (P = 0.0001) and a simultaneous increase in activated cytotoxic T-lymphocyte antigen 4 (CTLA-4)+ cluster of differentiation (CD)4+ (P < 0.001) and CD8+ (P = 0.032) Tcells, consistent with reduction of systemic immune suppression allowing for effector T-cell activation, peaking 14 days after IRE. Effects were positively correlated with tumour volume/ablation size. Accordingly, IRE induced expansion of PSAP and/or NY-ESO-1 specific T-cell responses in four of the eight immune competent patients. Temporarily increased activated myeloid derived suppressor cell frequencies (P = 0.047) were consistent with transient immunosuppression after RARP. Irreversible electroporation induces a PCa-specific systemic immune response in patients with localised PCa, aiding conversion of the tumour microenvironment into a more immune permissive state. Therapeutic efficacy might be further enhanced by combination with CTLA-4 checkpoint inhibition, potentially opening up a new synergistic treatment paradigm for high-risk localised or (oligo)metastatic disease.

Immune status of patients with community-acquired pneumonia associated with a new coronavirus infection and other viral and bacterial pathogens

Despite the fact that the state of the individual’s immune system plays an important role in developing community-acquired pneumonia, its clinical features are determined not only by immune response characteristics, but also by the nature of the infectious agent. The aim of the work was to assess immune status of patients with community-acquired pneumonia with lung damage ranging from 2 to 12%, in whom pathogens of a viral, bacterial and fungal nature were verified (n = 96, aged 46,3±20,5) who were admitted to the hospital 5–7 days after disease onset. Materials and methods. The selection of smears and sputum specimens was carried out on day 1 after admission. COVID-19 pathogen was analyzed in smears by PCR using the Vector-PCRR-2019-nCoV-RG kit (SSC Vector of Rospotrebnadzor, Russia). Biochemical activity, colony morphology, and pathogen concentration (in the amount of ≥ 105 CFU/ml) were also evaluated. Based on the results of preliminary studies, target patients groups were formed: with a new coronavirus infection caused by the SARS-CoV-2 gene variant B.1.1.529 (Omicron) (n = 33); with COVID-19 and bacterial pathogens (n = 17); with COVID-19 and combined bacterial and fungal infection (n = 16); patients with identified pathogens of bacterial infections (n = 13); patients with combined bacterial and fungal infection (n = 17). The relative and absolute level of CD45+CD3+ lymphocytes, CD45+CD3+CD4+ cells, CD45+CD3+CD8+ lymphocytes, CD45+CD3-CD16+CD56+ cells, CD45+CD3+CD16+CD56+ lymphocytes, CD45+CD45RO–CD45RA+ and CD45+CD45RO+CD45RA– lymphocytes, CD45+CD19+ cells, CD45+CD5+CD19–CD27– and CD45+CD19+CD5–CD27– lymphocytes, CD45+CD19+CD5–CD27+ cells was assessed in all volunteers. Results. The analysis of the immune status of patients with community-acquired pneumonia associated with Omicron gene variant new coronavirus infection revealed T-lymphocytopenia, a decreased number of CD8+ lymphocytes, an increased relative and absolute number of NK cells. In COVID-19 patients, who also had bacterial pathogens verified, there was a decrease in relative and absolute number of T-helper cells, an increased relative and absolute number of B and B2 lymphocytes. In COVID-19-negative volunteers with bacterial and bacterial-fungal community-acquired pneumonia, the relative and absolute level of B and B2 lymphocytes, as well as the general memory B cell population, was increased. In contrast to COVID-19-positive patients, in the absence of T-lymphocytopenia, a decreased number of CD4+ cells and rise in number of cytotoxic lymphocytes were recorded in patients of these groups. Conclusions. The data obtained indicate that in the immune status of patients with community-acquired pneumonia, depending on the nature of the infectious agent, changes in relative and absolute level of T-helper cells, cytotoxic lymphocytes, as well as in the qualitative and quantitative B-lymphocyte population composition are recorded.

Features of T-cell and humoral immunity of patients with acute coronary syndrome, with and without COVID-19, depending on/peripheral blood B-lymphocytes with the phenotype CD3–CD19+CD5+ level

The aim of the work was to assess the T-cell and humoral immune arms in patients with acute coronary syndrome (ACS) recovered from or not exposed to COVID-19. 86 men with ACS aged 40 to 65 years old, who suffered or not exposed to COVID-19, which required stenting of coronary arteries, were examined. Depending on the peripheral blood B-lymphocyte CD3–CD19+CD5+ level and the former COVID-19 history, all patients were divided into 6 groups. Of the previously COVID-19 exposed subjects CD3–CD19+CD5+ lymphocytes were at: reduced (group 1), normal (group 2), increased (group 3) level. COVID-19 unexposed subjects had CD3–CD19+CD5+ lymphocyte level: reduced (group 4), normal (group 5), increased (group 6). The most severe clinical manifestations were observed in group 1: with a larger rate of stent thrombosis and increased mortality. In absolute numbers, T-lymphocytes were significantly lower in group 1 compared to other groups, except group 4. The lowest both relative and absolute T-helper cell counts were recorded in covid-19 patients, with reduced CD3–CD19+CD5+ cell level. NK-lymphocytes both in relative and absolute level were significantly (p 0.05) higher in patients who suffered from COVID-19 as compared to those in patients unexposed to previous COVID-19. Percentage of late-activation T-regulatory cells was minimal in patients with former COVID-19 along with high B-lymphocyte CD3–CD19+CD5+ level, which significantly (p 0.05) differed from those in subjects lacking former COVID-19 history. In addition, significantly lower B-lymphocyte CD3–CD19+CD5– level was found in group 1 and 4. The IgM level peaked in group 5 — subjects lacking former COVID-19 history and having normal CD3–CD19+CD5+ cell level that significantly differed in comparison with that of in group 1, 2, 3. At the same time, the maximum value of IgG level was recorded in COVID-19 patients with normal CD3–CD19+CD5+ cells, and significantly differed from those found in group 5 and 6. C1-inhibitor level was higher in group 3 that significantly differed from that in other groups. SARS-CoV-2-specific IgG and IgM levels were significantly higher in COVID-19-positive vs. COVID-19-negative patients. Conclusion. In patients who have suffered COVID-19 with low B-lymphocyte CD3–CD19+CD5+ level, a significantly compromised immune protection was noted in comparison with other groups: a decline in total T-lymphocyte, T-helper, early- and late-activation T-lymphocyte, T-regulatory cell, B-lymphocyte CD3–CD19+CD5– levels, which was associated with a more severe disease course characterized by stent thrombosis and large mortality.

Longitudinal analysis at pre- and post-flare of T peripheral helper and T follicular helper subsets in patients with systemic lupus erythematosus

ObjectiveWe focused to analyze the time-course changes at pre- and post-flare of T peripheral helper (Tph) cells and circulating T follicular helper (Tfh) cells in the blood of patients with systemic lupus erythematosus (SLE) with lupus low disease activity state (LLDAS) before flare. MethodsThis study included inactive (n = 29) and active (n = 55) patients with SLE. Tph subsets, Tfh subsets, CD11chi B cells, and plasma cells in the blood were determined by flow cytometry. The blood levels of cytokines including interferons (IFNs) were measured by electrochemiluminescence assay or cytokine beads array. ResultsActive SLE patients exhibited the increased frequency of Tph1, Tph2, Tfh1, and Tfh2 subsets when compared to inactive patients, but no clear changes in the other subsets. During the treatment with medications, Tph1, Tph2, and Tfh2 subsets were significantly reduced along with disease activity and Tph1 and Tph2 subsets were positively correlated with SLE disease activity index (SLEDAI). The time course analysis of patients at pre- and post-flare revealed that in the patients at LLDAS before flare, Tph subsets and Tfh subsets were relatively low levels. At the flare, Tph cells, particularly Tph1 and Tph2 subsets, were increased and correlated with SLEDAI. Furthermore, the blood levels of IFN-α2a, IFN-γ, and IFN-λ1 were low in the patients with LLDAS before flare but these IFNs, particularly IFN-λ1, were increased along with flare. ConclusionIncreased frequency of Tph1 and Tph2 subsets and elevated levels of serum IFN-λ1 are presumably critical for triggering of flare in SLE.

Immune Responses in the Harderian Gland After Newcastle Disease Vaccination in Chickens with Maternal Antibodies.

Immune responses in the Harderian gland (HG) were characterized after Newcastle disease virus (NDV) LaSota ocular vaccination in antibody-naïve specific-pathogen-free (SPF) chickens and in chickens of commercial origin with NDV maternally derived antibodies (MDA). Ocular LaSota vaccination of 13-day-old white leghorn SPF chickens elicited serum antibody levels that consistently increased 15 days postvaccination, while the specific IgA response in lacrimal fluids was already detectable 10 days after vaccination. Eleven days postvaccination, the relative abundance of B cells, as well as T-helper cells (CD4+) and cytotoxic T cells (CD8+), in HGs was significantly increased, achieving maximum frequencies 16 days postvaccination. In a second experiment, chickens with MDA originating from NDV-vaccinated commercial white leghorn layer breeders, as well as white leghorn SPF chickens, were vaccinated with NDV LaSota. The LaSota virus successfully replicated in periocular tissues and in the trachea both in commercial and control SPF chickens after vaccination at 2 or 15 days of age (DOA). Vaccination at 2 DOA did not induce a serum NDV antibody response in chickens of commercial origin. In contrast, seroconversion was elicited in commercial chickens upon vaccination at 15 DOA, likely associated with waning of MDA. Unlike systemic IgG responses, vaccination at 2 or 15 DOA elicited strong specific IgA responses in lacrimal fluids in commercial chickens. The IgA response was highest 9 days after vaccination and showed a tendency to decline 15 days postvaccination. Commercial chickens vaccinated at 2 DOA showed increased B cells in HG 10 and 16 days postvaccination. The expansion of B cells in the HG in these chickens is consistent with increased IgA levels detected in lacrimal fluids. In contrast, control SPF chickens showed a more limited B-cell expansion in HG and lower IgA levels. Vaccination at 15 DOA also triggered a greater increase of B cells in HGs in commercial chickens than in control SPF chickens. The B-cell response was accompanied by T-helper (CD4+) cell expansion, occurring both in commercial and control SPF chickens. These cells expanded to a lesser extent when vaccination was performed at 2 DOA compared with vaccination at 15 DOA. CD8+ showed significant expansion irrespective of vaccination day and without differences detected between control SPF chickens and chickens with MDA. We conclude that NDV LaSota elicits vigorous humoral and cell immune responses in the HG. Furthermore, unlike the interference shown by MDA on vaccine-induced serum antibody responses, MDA do not interfere with the mucosal immune response of the HG.

A chemogenetic screen reveals that Trpv1-expressing neurons control regulatory T cells in the gut.

Neuroimmune cross-talk participates in intestinal tissue homeostasis and host defense. However, the matrix of interactions between arrays of molecularly defined neuron subsets and of immunocyte lineages remains unclear. We used a chemogenetic approach to activate eight distinct neuronal subsets, assessing effects by deep immunophenotyping, microbiome profiling, and immunocyte transcriptomics in intestinal organs. Distinct immune perturbations followed neuronal activation: Nitrergic neurons regulated T helper 17 (TH17)-like cells, and cholinergic neurons regulated neutrophils. Nociceptor neurons, expressing Trpv1, elicited the broadest immunomodulation, inducing changes in innate lymphocytes, macrophages, and RORγ+ regulatory T (Treg) cells. Neuroanatomical, genetic, and pharmacological follow-up showed that Trpv1+ neurons in dorsal root ganglia decreased Treg cell numbers via the neuropeptide calcitonin gene-related peptide (CGRP). Given the role of these neurons in nociception, these data potentially link pain signaling with gut Treg cell function.

Spatial effects of infiltrating T cells on neighbouring cancer cells and prognosis in stage III CRC patients.

Colorectal cancer (CRC) is one of the most frequently occurring cancers, but prognostic biomarkers identifying patients at risk of recurrence are still lacking. In this study, we aimed to investigate in more detail the spatial relationship between intratumoural T cells, cancer cells, and cancer cell hallmarks as prognostic biomarkers in stage III colorectal cancer patients. We conducted multiplexed imaging of 56 protein markers at single-cell resolution on resected fixed tissue from stage III CRC patients who received adjuvant 5-fluorouracil (5FU)-based chemotherapy. Images underwent segmentation for tumour, stroma, and immune cells, and cancer cell 'state' protein marker expression was quantified at a cellular level. We developed a Python package for estimation of spatial proximity, nearest neighbour analysis focusing on cancer cell-T-cell interactions at single-cell level. In our discovery cohort (Memorial Sloan Kettering samples), we processed 462 core samples (total number of cells: 1,669,228) from 221 adjuvant 5FU-treated stage III patients. The validation cohort (Huntsville Clearview Cancer Center samples) consisted of 272 samples (total number of cells: 853,398) from 98 stage III CRC patients. While there were trends for an association between the percentage of cytotoxic T cells (across the whole cancer core), it did not reach significance (discovery cohort: p = 0.07; validation cohort: p = 0.19). We next utilised our region-based nearest neighbour approach to determine the spatial relationships between cytotoxic T cells, helper T cells, and cancer cell clusters. In both cohorts, we found that shorter distance between cytotoxic T cells, T helper cells, and cancer cells was significantly associated with increased disease-free survival. An unsupervised trained model that clustered patients based on the median distance between immune cells and cancer cells, as well as protein expression profiles, successfully classified patients into low-risk and high-risk groups (discovery cohort: p = 0.01; validation cohort: p = 0.003). © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Abstract We053: Altered inflammatory state and mitochondrial function identified by transcriptomics in paediatric congenital heart patients prior to surgical repair

Background: Congenital heart disease (CHD) remains the most common birth defect, with surgical intervention required in complex cases. In contrast to adult heart disease which disproportionately affects the left ventricle, complex CHD can be characterized by increased right ventricular (RV) pressure, leading to RV hypertrophy and eventually failure, with RV function known to be a major predictor in sustained cardiac health in these patients. Methods: RV samples were collected from discarded myocardial tissue from paediatric patients (0-16 years) undergoing their first cardiac surgery at Bristol Royal Hospital for Children or obtained from autopsy subjects. RNA sequencing and subsequent cellular deconvolution was conducted in CHD samples and integrated with publicly available control dataset. Cellular deconvolution, pathway network analysis and gene ontology were conducted and changes in expression of markers was confirmed via histological analysis. Results: Presence of CHD drove divergence of transcriptome with 511 differentially expressed genes (log fold change≥±2, padj≤0.05), with 82% shared homology. Known CHD genes; TBX5 , JAG1, NOTCH2 and NOTCH1 were reduced in CHD compared to controls (padj=2.24 E-07 , 1.38 E-27 , 7.76 E-31 , 9.11 E-7 ) . Conversely, mitochondrial dysfunction genes RPPH1 and RMPR (padj=4.67 E-132 , 2.23 E-107 ) were increased. Gene set enrichment identified mitochondrial dysfunctional pathways.Negative regulation of mitochondrial functions and metabolism was identified in functional network analysis. T helper cell markers CD4 and SELL were significantly downregulated (p&lt;0.0001, p=0.003). Cytotoxic T cell markers CD8a, LAGE3 and CD49a were significantly increased in CHD compared to control (p=0.0006, p&lt;0.0001, p=0.0118) as was proinflammatory marker Caspase1 (p=0.0055). Histological analysis confirmed an increase in CD45 and CD8 positive cellular bodies with the CHD tissue, which was absent in control. Deconvolution of bulk RNAseq data suggests a reduction in CD4+ T cells (p=0.0067) and an increase in CD8+ T cells (p=0.0223). Network analysis identified positive regulation of the immune system and cytokine signalling clusters within the inflammation functional network as were lymphocyte activation and leukocyte differentiation. Conclusions: Utilizing RV tissue from paediatric patients undergoing CHD cardiac surgery this study identifies dysfunctional mitochondrial pathways and an increase in inflammatory T cell presence prior to reparative surgery.

Novel prophylactic and therapeutic multi-epitope vaccine based on Ag85A, Ag85B, ESAT-6, and CFP-10 of Mycobacterium tuberculosis using an immunoinformatics approach.

Current tuberculosis (TB) control strategies face limitations, such as low antibiotic treatment compliance and a rise in multidrug resistance. Furthermore, the lack of a safe and effective vaccine compounds these challenges. The limited efficacy of existing vaccines against TB underscores the urgency for innovative strategies, such as immunoinformatics. Consequently, this study aimed to design a targeted multi-epitope vaccine against TB infection utilizing an immunoinformatics approach. The multi-epitope vaccine targeted Ag85A, Ag85B, ESAT-6, and CFP-10 proteins. The design adopted various immunoinformatics tools for cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL), and linear B lymphocyte (LBL) epitope prediction, the assessment of vaccine characteristics, structure modeling, population coverage analysis, disulfide engineering, solubility prediction, molecular docking/dynamics with toll-like receptors (TLRs), codon optimization/cloning, and immune simulation. The multi-epitope vaccine, which was assembled using 12 CTL, 25 HTL, and 21 LBL epitopes associated with CpG adjuvants, showed promising characteristics. The immunoinformatics analysis confirmed the antigenicity, immunogenicity, and lack of allergenicity. Physicochemical evaluations indicated that the proteins were stable, thermostable, hydrophilic, and highly soluble. Docking simulations suggested high-affinity binding to TLRs, including TLR2, TLR4, and TLR9. In silico immune simulation predicted strong T cell (cytokine release) and B cell (immunoglobulin release) responses. This immunoinformatics-designed multi-epitope vaccine targeting Ag85A, Ag85B, ESAT-6, and CFP-10 proteins showed promising characteristics in terms of stability, immunogenicity, antigenicity, solubility, and predicted induction of humoral and adaptive immune responses. This suggests its potential as a prophylactic and therapeutic vaccine against TB.

Inherent preference for polyunsaturated fatty acids instigates ferroptosis of Treg cells that aggravates high-fat-diet-related colitis

Inflammatory bowel disease (IBD) has high prevalence in Western counties. The high fat content in Western diets is one of the leading causes for this prevalence; however, the underlying mechanisms have not been fully defined. Here, we find that high-fat diet (HFD) induces ferroptosis of intestinal regulatory T (Treg) cells, which might be the key initiating step for the disruption of immunotolerance and the development of colitis. Compared with effector Tcells, Treg cells favor lipid metabolism and prefer polyunsaturated fatty acids (PUFAs) for the synthesis of membrane phospholipids. Therefore, consumption of HFD, which has high content of PUFAs such as arachidonic acid, cultivates vulnerable Tregs that are fragile to lipid peroxidation and ferroptosis. Treg-cell-specific deficiency of GPX4, the key enzyme in maintaining cellular redox homeostasis and preventing ferroptosis, dramatically aggravates the pathogenesis of HFD-induced IBD. Taken together, these studies expand our understanding of IBD etiology.

Knockdown of long noncoding RNA AL161431.1 inhibits malignant progression of cholangiocarcinoma.

Cholangiocarcinoma (CCA) is one of the most deadly cancers in the world. It usually has a bad prognosis and is challenging to identify in its early stages. Long noncoding RNAs (lncRNAs) have been shown in an increasing number of studies to be important in the control of signaling pathways, cell behaviors, and epigenetic modification that contribute to the growth of tumors. The purpose of this work was to examine the relationship between CCA and lncRNA AL161431.1. Using TCGA clinical survival data, we evaluated the association between AL161431.1 expression and patient prognosis. Using the program cluster Profiler R, enrichment analysis was performed. Additionally, the association between immune cell infiltration and AL161431.1 expression was evaluated by a review of the TCGA database. Next, to ascertain if AL161431.1 influences tumor growth, migration, and invasion in CCA, functional in vitro assays were conducted. Quantitative real-time polymerase chain reaction (qPCR) was employed to gauge AL161431.1 expression levels in CCA cells. Western blot was used to measure protein levels. In CCA, AL161431.1 was extremely expressed. The patients in the high-risk group had a significantly poorer overall survival (OS) than the patients in the low-risk group. A more thorough look at the TCGA data showed a relationship between high expression levels of AL161431.1 and increased infiltration of T cells, T helper cells, and NK CD56dim cells. Furthermore, AL161431.1 knockdown in CCA cells impeded invasion, migration, and proliferation and also lowered the expression of phosphorylated Smad2/Smad3 to restrain the TGFβ/SMAD signaling pathway. Our results indicate that the lncRNA AL161431.1 activates the TGFβ/SMAD signaling pathway to enhance CCA development and metastasis. AL161431.1 could be a novel target for cholangiocarcinoma treatment or a diagnostic marker.

Antigen-driven Convergent Evolution of Polysaccharide-specific "DH-less" B Cells in Glycoconjugate Immunized Mice.

Glycoconjugate vaccines elicit robust anti-polysaccharide Ab response by recruiting T-cell help. Multiple doses of glycoconjugate vaccine are required to induce long-lasting immunity. The characteristics of anti-polysaccharide Ab response have been reported previously. However, the effect of glycoconjugate booster immunization on anti-polysaccharide and anti-carrier protein Ab repertoire remains poorly understood. In this study, we used clinically relevant pneumococcal capsular polysaccharide type 14 (PCP14) conjugated with cross-reactive material 197 (CRM197) as a model glycoconjugate Ag (PCP14-CRM197). We performed a comprehensive sequence analysis of mouse mAbs generated against PCP14 and CRM197 following immunization with one or three doses of PCP14-CRM197. Analysis of the paired Ig H and L chain transcripts revealed that anti-PCP14 Ab repertoire is extremely restricted. The reoccurrence of five replacement mutations at identical positions in anti-polysaccharide mAbs generated from different mice provided evidence for Ag-driven selection in PCP14-specific B cells. Convergent evolution was observed wherein distinct V(D)J rearrangements resulted in identical or nearly identical CDR3 in anti-PCP14 mAbs. Abs that lacked DH encoded amino acids dominated the anti-PCP14 Ab response. In contrast, anti-CRM197 Ab response was quite diverse, with fewer mutations compared with the anti-PCP14 mAbs, suggesting that conjugation of the polysaccharide to a carrier protein interferes with the development of carrier protein-specific Ab responses. Our findings provide molecular insights into the maturation of Ab responses driven by booster doses of glycoconjugate. This has fundamental implications for the design of glycoconjugate vaccines, especially where the development of Ab response against the carrier protein is also crucial.

Follicular Helper T Cells in Peyer's Patches and Galactose- Deficient Iga1 Contribute to Iga Nephropathy.

Common primary glomerulonephritis with aberrant mucosal immunity is IgA nephropathy (IgAN). T follicular helper (TFH) cells are essential in regulating B cell differentiation. Peyer's patches (PPs) are the main site where IgA+ plasmablasts differentiate. Our study aimed to investigate the TFH cell's potential contribution to the etiology of IgA nephropathy. In PPs from IgAN mouse models, the ratio of the TFH cell, B220+IgA+, B220+IgM+, and B220-IgA+ lymphocytes were assessed. Then, we used Western blot to assess the expression of Bcl-6, Blimp- 1, and IL-21 proteins in PPs and used RTPCR to assess the expression of IL-21 and TGF-β1 mRNA. TFH cells coculture with spleen cells to measure the degree of IL-21 and the ratio of activation marker CD69 on the TFH cells. Naive B cells (CD27-IgD+) from children suffering from IgAN were cultured with TFH cell-related cytokines. The supernatant was detected to assess the excretion of galactose-deficient IgA1 (Gd-IgA1). IgAN mice developed noticeably increased degrees of IL-21 and CD69 on TFH cells than controls did, as well as higher percentages of B220+IgA+, B220+IgM+, B220+IgA+, TGF- β1, and IL-21 mRNA and Bcl-6, IL-21 proteins in PPs. The Gd-IgA1 level in the supernatant and IgAN- positive children's serum were noticeably higher than those of the healthy controls (P < 0.05). PPs provide the microenvironment to induce the production of IgA-secreting plasmablasts. TFH cells may be a key moderator to induce B cell differentiation into IgAsecreting plasmablasts and produce Gd-IgA1, which plays a significant part in IgAN's pathogenesis. It could be a new therapeutic target in the future.