Regulation of inflammation, autoimmunity, and infection immunity by HVEM-BTLA signaling

Generation and External Validation of a Histologic Transformation Risk Model for Patients with Follicular Lymphoma

Follicular lymphoma (FL) is the most frequent indolent lymphoma. Some patients (10%-15%) experience histologic transformation (HT) to a more aggressive lymphoma, usually diffuse large B-cell lymphoma (DLBCL). This study aimed to validate and improve a genetic risk model to predict HT at diagnosis.We collected mutational data from diagnosis biopsies of 64 FL patients. We combined them with the data from a previously published cohort (total n = 104; 62 from nontransformed and 42 from patients who did transform to DLBCL). This combined cohort was used to develop a nomogram to estimate the risk of HT. Prognostic mutated genes and clinical variables were assessed using Cox regression analysis to generate a risk model. The model was internally validated by bootstrapping and externally validated in an independent cohort. Its performance was evaluated using a concordance index and a calibration curve. The clinicogenetic nomogram included the mutational status of 3 genes (HIST1HE1, KMT2D, and TNFSR14) and high-risk Follicular Lymphoma International Prognostic Index and predicted HT with a concordance index of 0.746. Patients were classified as being at low or high risk of transformation. The probability HT function at 24 months was 0.90 in the low-risk group vs 0.51 in the high-risk group and, at 60 months, 0.71 vs 0.15, respectively. In the external validation cohort, the probability HT function in the low-risk group was 0.86 vs 0.54 in the high-risk group at 24 months, and 0.71 vs 0.32 at 60 months. The concordance index in the external cohort was 0.552. In conclusion, we propose a clinicogenetic risk model to predict FL HT to DLBLC, combining genetic alterations in HIST1H1E, KMT2D, and TNFRSF14 genes and clinical features (Follicular Lymphoma International Prognostic Index) at diagnosis. This model could improve the management of FL patients and allow treatment strategies that would prevent or delay transformation.

BTLA contributes to acute-on-chronic liver failure infection and mortality through CD4+ T-cell exhaustion

B- and T-lymphocyte attenuator (BTLA) levels are increased in patients with hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF). This condition is characterized by susceptibility to infection and T-cell immune exhaustion. However, whether BTLA can induce T-cell immune exhaustion and increase the risk of infection remains unclear. Here, we report that BTLA levels are significantly increased in the circulating and intrahepatic CD4+ T cells from patients with HBV-ACLF, and are positively correlated with disease severity, prognosis, and infection complications. BTLA levels were upregulated by the IL-6 and TNF signaling pathways. Antibody crosslinking of BTLA activated the PI3K-Akt pathway to inhibit the activation, proliferation, and cytokine production of CD4+ T cells while promoting their apoptosis. In contrast, BTLA knockdown promoted their activation and proliferation. BTLA-/- ACLF mice exhibited increased cytokine secretion, and reduced mortality and bacterial burden. The administration of a neutralizing anti-BTLA antibody reduced Klebsiella pneumoniae load and mortality in mice with ACLF. These data may help elucidate HBV-ACLF pathogenesis and aid in identifying novel drug targets.

The Role of the CD28 Family Receptors in T-Cell Immunomodulation

The CD28 family receptors include the CD28, ICOS (inducible co-stimulator), CTLA-4 (cytotoxic T-lymphocyte antigen-4), PD-1 (programmed cell death protein 1), and BTLA (B- and T-lymphocyte attenuator) molecules. They characterize a group of molecules similar to immunoglobulins that control the immune response through modulating T-cell activity. Among the family members, CD28 and ICOS act as enhancers of T-cell activity, while three others-BTLA, CTLA-4, and PD-1-function as suppressors. The receptors of the CD28 family interact with the B7 family of ligands. The cooperation between these molecules is essential for controlling the course of the adaptive response, but it also significantly impacts the development of immune-related diseases. This review introduces the reader to the molecular basis of the functioning of CD28 family receptors and their impact on T-cell activity.

Single-cell RNA landscape of osteoimmune microenvironment in osteoporotic vertebral compression fracture and Kümmell's disease

Background: Single-cell RNA sequencing (scRNA-seq) enables specific analysis of cell populations at single-cell resolution; however, there is still a lack of single-cell-level studies to characterize the dynamic and complex interactions between osteoporotic vertebral compression fractures (OVCFs) and Kümmell's disease (KD) in the osteoimmune microenvironment. In this study, we used scRNA-seq analysis to investigate the osteoimmune microenvironment and cellular composition in OVCFs and KD. Methods: ScRNA-seq was used to perform analysis of fractured vertebral bone tissues from one OVCF and one KD patients, and a total of 8,741 single cells were captured for single-cell transcriptomic analysis. The cellularity of human vertebral bone tissue was further analyzed using uniform manifold approximation and projection. Pseudo-time analysis and gene enrichment analysis revealed the biological function of cell fate and its counterparts. CellphoneDB was used to identify the interactions between bone cells and immune cells in the osteoimmune microenvironment of human vertebral bone tissue and their potential functions. Results: A cellular profile of the osteoimmune microenvironment of human vertebral bone tissue was established, including mesenchymal stem cells (MSCs), pericytes, myofibroblasts, fibroblasts, chondrocytes, endothelial cells (ECs), granulocytes, monocytes, T cells, B cells, plasma cells, mast cells, and early erythrocytes. MSCs play an immunoregulatory function and mediate osteogenic differentiation and cell proliferation. The differentiation trajectory of osteoclasts in human vertebral bone tissue was also revealed. In addition, ECs actively participate in inflammatory infiltration and coupling with bone cells. T and B cells actively participate in regulating bone homeostasis. Finally, by identifying the interaction of ligand-receptor pairs, we found that immune cells and osteoclasts have bidirectional regulatory characteristics, have the effects of regulating bone resorption by osteoclasts and promoting bone formation, and are essential for bone homeostasis. It is also highlighted that CD8-TEM cells and osteoclasts might crosstalk via CD160-TNFRSF14 ligand-receptor interaction. Conclusion: Our analysis reveals a differential landscape of molecular pathways, population composition, and cell-cell interactions during OVCF development into KD. OVCFs exhibit a higher osteogenic differentiation capacity, owing to abundant immune cells. Conversely, KD results in greater bone resorption than bone formation due to depletion of MSCs and a relatively suppressed immune system, and this immune imbalance eventually leads to vertebral avascular necrosis. The site of action between immune cells and osteoclasts is expected to be a new therapeutic target, and these results may accelerate mechanistic and functional studies of osteoimmune cell types and specific gene action in vertebral avascular necrosis and pathological bone loss diseases, paving the way for drug discovery.

Pre-treatment inflamed tumor immune microenvironment is associated with FOLFIRINOX response in pancreatic cancer

Introduction

Pancreatic adenocarcinoma (PDAC) is an aggressive tumor with limited response to both chemotherapy and immunotherapy. Pre-treatment tumor features within the tumor immune microenvironment (TiME) may influence treatment response. We hypothesized that the pre-treatment TiME composition differs between metastatic and primary lesions and would be associated with response to modified FOLFIRINOX (mFFX) or gemcitabine-based (Gem-based) therapy.

Methods

Using RNAseq data from a cohort of treatment-naïve, advanced PDAC patients in the COMPASS trial, differential gene expression analysis of key immunomodulatory genes in were analyzed based on multiple parameters including tumor site, response to mFFX, and response to Gem-based treatment. The relative proportions of immune cell infiltration were defined using CIBERSORTx and Dirichlet regression.

Results

145 samples were included in the analysis; 83 received mFFX, 62 received Gem-based therapy. Metastatic liver samples had both increased macrophage (1.2 times more, p < 0.05) and increased eosinophil infiltration (1.4 times more, p < 0.05) compared to primary lesion samples. Further analysis of the specific macrophage phenotypes revealed an increased M2 macrophage fraction in the liver samples. The pre-treatment CD8 T-cell, dendritic cell, and neutrophil infiltration of metastatic samples were associated with therapy response to mFFX (p < 0.05), while mast cell infiltration was associated with response to Gem-based therapy (p < 0.05). Multiple immunoinhibitory genes such as ADORA2A, CSF1R, KDR/VEGFR2, LAG3, PDCD1LG2, and TGFB1 and immunostimulatory genes including C10orf54, CXCL12, and TNFSF14/LIGHT were significantly associated with worse survival in patients who received mFFX (p = 0.01). There were no immunomodulatory genes associated with survival in the Gem-based cohort.

Discussion

Our evidence implies that essential differences in the PDAC TiME exist between primary and metastatic tumors and an inflamed pretreatment TiME is associated with mFFX response. Defining components of the PDAC TiME that influence therapy response will provide opportunities for targeted therapeutic strategies that may need to be accounted for in designing personalized therapy to improve outcomes.

B- and T-lymphocyte attenuator could be a new player in accelerated atherosclerosis associated with chronic kidney disease

BACKGROUND

In chronic kidney disease (CKD), cardiovascular morbi-mortality is higher than in general population. Atherosclerotic cardiovascular disease is accelerated in CKD, but specific CKD-related risk factors for atherosclerosis are unknown.

METHODS

CKD patients from the NEFRONA study were used. We performed mRNA array from blood of patients free from atheroma plaque at baseline, with (n=10) and without (n=10) de novo atherosclerotic plaque development 2 years later. Selected mRNA candidates were validated in a bigger sample (n=148). Validated candidates were investigated in vivo in an experimental model of CKD-accelerated atherosclerosis, and in vitro in murine macrophages.

RESULTS

mRNA array analysis showed 92 up-regulated and 67 down-regulated mRNAs in samples from CKD patients with de novo plaque development. The functional analysis pointed to a paramount role of the immune response. The validation in a bigger sample confirmed that B- and T-lymphocyte co-inhibitory molecule (BTLA) down-regulation was associated with de novo plaque presence after 2 years. However, BTLA down-regulation was not found to be associated with atherosclerotic progression in patients with plaque already present at baseline. In a model of CKD-accelerated atherosclerosis, mRNA and protein expression levels of BTLA were significantly decreased in blood samples and atheroma plaques. Plaques from animals with CKD were bigger, had more infiltration of inflammatory cells, higher expression of IL6 and IL17 and less presence of collagen than plaques from control animals. Incubation of macrophages with rat uremic serum decreased BTLA expression.

CONCLUSIONS

BTLA could be a potential biomarker or therapeutic target for atherosclerosis incidence in CKD patients.

Beyond the anti-PD-1/PD-L1 era: promising role of the BTLA/HVEM axis as a future target for cancer immunotherapy

Recent introduction of monoclonal antibodies targeting immune checkpoints to harness antitumor immunity has revolutionized the cancer treatment landscape. The therapeutic success of immune checkpoint blockade (ICB)-based therapies mainly relies on PD-1/PD-L1 and CTLA-4 blockade. However, the limited overall responses and lack of reliable predictive biomarkers of patient´s response are major pitfalls limiting immunotherapy success. Hence, this reflects the compelling need of unveiling novel targets for immunotherapy that allow to expand the spectrum of ICB-based strategies to achieve optimal therapeutic efficacy and benefit for cancer patients. This review thoroughly dissects current molecular and functional knowledge of BTLA/HVEM axis and the future perspectives to become a target for cancer immunotherapy. BTLA/HVEM dysregulation is commonly found and linked to poor prognosis in solid and hematological malignancies. Moreover, circulating BTLA has been revealed as a blood-based predictive biomarker of immunotherapy response in various cancers. On this basis, BTLA/HVEM axis emerges as a novel promising target for cancer immunotherapy. This prompted rapid development and clinical testing of the anti-BTLA blocking antibody Tifcemalimab/icatolimab as the first BTLA-targeted therapy in various ongoing phase I clinical trials with encouraging results on preliminary efficacy and safety profile as monotherapy and combined with other anti-PD-1/PD-L1 therapies. Nevertheless, it is anticipated that the intricate signaling network constituted by BTLA/HVEM/CD160/LIGHT involved in immune response regulation, tumor development and tumor microenvironment could limit therapeutic success. Therefore, in-depth functional characterization in different cancer settings is highly recommended for adequate design and implementation of BTLA-targeted therapies to guarantee the best clinical outcomes to benefit cancer patients.

Dietary Debaryomyces hansenii promotes skin and skin mucus defensive capacities in a marine fish model

The present study explores the effects of two supplementation levels of Debaryomyces hansenii (1.1% and 2.2%) as a probiotic in a reference low fish meal-based diet on the skin mucosal tissue in Sparus aurata. This study includes the evaluation of fish performance coupled with a holistic study of the skin mucosa: i) a transcriptomic study of the skin tissue, and ii) the evaluation of its secreted mucus both in terms of skin mucosal-associated biomarkers and its defensive capacity by means of co-culture analysis with two pathogenic bacteria. Results showed that after 70 days of diet administration, fish fed the diet supplemented with D. hansenii at 1.1% presented increased somatic growth and a better feed conversion ratio, compared to fish fed the control diet. In contrast, fish fed the diet including 2.2% of the probiotic presented intermediate values. Regarding gene regulation, the probiotic administration at 1.1% resulted in 712 differentially expressed genes (DEGs), among which 53.4% and 46.6% were up- and down-regulated, respectively. In particular, D. hansenii modulated some skin biological processes related to immunity and metabolism. Specifically, D. hansenii administration induced a strong modulation of some immune biological-related processes (61 DEGs), mainly involved in B- and T-cell regulatory pathways. Furthermore, dietary D. hansenii promoted the skin barrier function by the upregulation of anchoring junction genes (23 DEGs), which reinforces the physical defense against potential skin damage. In contrast, the skin showed modulated genes related to extracellular exosome and membrane organization (50 DEGs). This modulated functioning is of great interest, particularly in relation to the increased skin mucus defensive capacity observed in the bacterial co-culture in vitro trials, which could be related to the increased modulation and exudation of the innate immune components from the skin cells into the mucus. In summary, the modulation of innate immune parameters coupled with increased skin barrier function and cell trafficking potentiates the skin's physical barrier and mucus defensive capacity, while maintaining the skin mucosa's homeostatic immune and metabolic status. These findings confirmed the advantages of D. hansenii supplementation in low fish meal-based diets, demonstrating the probiotic benefits on cultured marine species.

Epitope topography of agonist antibodies to the checkpoint inhibitory receptor BTLA

B and T lymphocyte attenuator (BTLA) is an attractive target for a new class of therapeutics that attempt to rebalance the immune system by agonizing checkpoint inhibitory receptors (CIRs). Herpesvirus entry mediator (HVEM) binds BTLA in both trans- and cis-orientations. We report here the development and structural characterization of three humanized BTLA agonist antibodies, 22B3, 25F7, and 23C8. We determined the crystal structures of the antibody-BTLA complexes, showing that these antibodies bind distinct and non-overlapping epitopes of BTLA. While all three antibodies activate BTLA, 22B3 mimics HVEM binding to BTLA and shows the strongest agonistic activity in functional cell assays and in an imiquimod-induced mouse model of psoriasis. 22B3 is also capable of modulating HVEM signaling through the BTLA-HVEM cis-interaction. The data obtained from crystal structures, biochemical assays, and functional studies provide a mechanistic model of HVEM and BTLA organization on the cell surface and informed the discovery of a highly active BTLA agonist.

An explorative study on proteomic analyses related to inflammation and pain in children with juvenile idiopathic arthritis

BACKGROUND

Our aim was attempting to find proteins involved in the pain process and correlating with pain but not degree of inflammation in children with juvenile idiopathic arthritis (JIA), using a proteomics panel.

METHODS

A total of 87 plasma samples were collected from 51 children with JIA (51 at diagnosis in a higher disease activity state, 18 at follow-up in a lower disease activity state) and 18 healthy controls. Relative levels of 92 proteins related to a wide range of biological processes in inflammation were obtained using a proximity extension assay panel. Comparisons between children with and without JIA, in different disease categories, by juvenile disease activity score (JADAS27) and degree of pain on a visual analogue scale (VAS), were performed using parametric and non-parametric statistical methods.

RESULTS

Nineteen proteins involved in arthritic inflammation, such as interleukin 6 (IL-6) and S100 protein A12, were higher in patients with JIA than controls, seven decreased significantly during treatment, and 18 correlated significantly with JADAS27. Three proteins correlated with pain VAS scores in unadjusted analyses: the glial cell line-derived neurotrophic factor (GDNF), transforming growth factor beta, and IL-18R1. Levels of GDNF correlated significantly with pain VAS scores but not with JADAS27.

CONCLUSIONS

Plasma levels of 18 of 92 tested proteins correlated with degree of disease activity. Levels of three proteins correlated with pain, and levels of one, GDNF, originating from neural cells, correlated with pain without correlating with inflammatory degree, suggesting that it may play a role in pain in JIA. Further studies in larger cohorts are warranted.

Reactivation of natural killer cells with monoclonal antibodies in the microenvironment of malignant neoplasms

Natural killer cells are critical players in the antitumor immune response due to their ability to destroy target cells through cytotoxic activity and other means. However, this response is inhibited in the tumor microenvironment, where a crippling hypoxic environment and several inhibitory molecules bind to NK cells to trigger an anergic state. Inhibitory receptors such as PD-1, NK2GA, KIR, TIGIT, and LAG-3 have been associated with inhibition of NK cells in multiple cancer types. Binding to these receptors leads to loss of cytotoxicity, lower proliferation and metabolic rates, and even apoptosis. While these receptors are important for avoiding auto-immunity, in a pathological setting like malignant neoplasms they are disadvantageous for the individual's immune system to combat cancer cells. The use of monoclonal antibodies to block these receptors contributes to cancer therapy by preventing the inhibition of NK cells. In this review, the impact of NK cell inhibition and activation on cancer therapy was summarized and an overview of the blockade of inhibitory pathways by monoclonal antibodies was provided.

Costimulatory and coinhibitory molecules of B7-CD28 family in cardiovascular atherosclerosis: A review

Accumulating evidence supports the active involvement of vascular inflammation in atherosclerosis pathogenesis. Vascular inflammatory events within atherosclerotic plaques are predominated by innate antigen-presenting cells (APCs), including dendritic cells, macrophages, and adaptive immune cells such as T lymphocytes. The interaction between APCs and T cells is essential for the initiation and progression of vascular inflammation during atherosclerosis formation. B7-CD28 family members that provide either costimulatory or coinhibitory signals to T cells are important mediators of the cross-talk between APCs and T cells. The balance of different functional members of the B7-CD28 family shapes T cell responses during inflammation. Recent studies from both mouse and preclinical models have shown that targeting costimulatory molecules on APCs and T cells may be effective in treating vascular inflammatory diseases, especially atherosclerosis. In this review, we summarize recent advances in understanding how APC and T cells are involved in the pathogenesis of atherosclerosis by focusing on B7-CD28 family members and provide insight into the immunotherapeutic potential of targeting B7-CD28 family members in atherosclerosis.

A novel chromatin regulator-related immune checkpoint related gene prognostic signature and potential candidate drugs for endometrial cancer patients

Background

Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries and its prevalence is increasing. As an emerging therapy with a promising efficacy, immunotherapy has been extensively applied in the treatment of solid tumors. In addition, chromatin regulators (CRs), as essential upstream regulators of epigenetics, play a significant role in tumorigenesis and cancer development.

Methods

CRs and immune checkpoint-related genes (ICRGs) were obtained from the previous top research. The Genome Cancer Atlas (TCGA) was utilized to acquire the mRNA expression and clinical information of patients with EC. Correlation analysis was utilized for screen CRs-related ICRGs (CRRICRGs). By Cox regression and least absolute shrinkage and selection operator (LASSO) analysis, prognosis related CRRICRGs were screened out and risk model was constructed. The Kaplan–Meier curve was used to estimate the prognosis between high- and low-risk group. By comparing the IC50 value, the drugs sensitivity difference was explored. We obtained small molecule drugs for the treatment of UCEC patients based on CAMP dataset.

Results

We successfully constructed a 9 CRRICRs-based prognostic signature for patients with UCEC and found the riskscore was an independent prognostic factor. The results of functional analysis suggested that CRRICRGs may be involved in immune processes associated with cancer. Immune characteristics analysis provided further evidence that the CRRICRGs-based model was correlated with immune cells infiltration and immune checkpoint. Eight small molecule drugs that may be effective for the treatment of UCEC patients were screened. Effective drugs identified by drug sensitivity profiling in high- and low-risk groups.

Conclusion

In summary, our study provided novel insights into the function of CRRICRGs in UCEC. We also developed a reliable prognostic panel for the survival of patients with UCEC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41065-022-00253-w.

The correlation of BTLA rs1982809 polymorphism with cancer susceptibility: A meta-analysis of 8634 participators

BACKGROUND

The connection between B and T lymphocyte attenuator rs1982809 polymorphism and cancer risk has been investigated by several studies and yielded different results. Therefore, we adopted the meta-analysis method to assess the association of rs1982809 polymorphism with the susceptibility of cancers synthetically.

METHODS

Eligible publications were gathered by retrieving PubMed, Web of Science, Embase, Wan Fang, and China National Knowledge Infrastructure. We utilized odds ratio (OR) and 95% confidence intervals (95% CI) to assess correlation intensity and performed subgroup analyses, sensitivity analyses, and publication bias assessments.

RESULTS

Six researches that encompassed 3678 cases and 4866 controls were incorporated into our meta-analysis. The rs1982809 polymorphism was proved to be connected with cancer risk by the meta-analysis in the additive model (G vs A: OR = 1.11, 95% CI = 1.04-1.19, Pheterogeneity= .096). Subgroup analyses revealed that this SNP is regarded as a susceptible factor for cancers in the dominant, heterozygous, and additive model (AG + GG vs AA: OR = 1.46, 95% CI = 1.19-1.80, Pheterogeneity= .592; AG vs AA: OR = 1.47, 95% CI = 1.19-1.82, Pheterogeneity= .536; G vs A: OR = 1.32, 95% CI = 1.12-1.55, Pheterogeneity= .745) in Caucasians; And this SNP may increase the susceptibility to lung cancer (GG vs AG+AA: OR = 1.20, CI = 1.01-1.44, Pheterogeneity= .854; G vs A: OR = 1.17, CI = 1.02-1.33, Pheterogeneity= .232).

CONCLUSION

The paper concludes that B and T lymphocyte attenuator rs1982809 polymorphism may contribute to cancers, especially in Caucasians, and it may associate with lung cancer.

Effect of Tensile Frequency on the Osteogenic Differentiation of Periodontal Ligament Stem Cells

Purpose

The role of periodontal ligament stem cells (PDLSCs) in mediating osteogenesis involved in orthodontic tooth movement (OTM) is well established. However, various relevant in vitro studies vary in the frequency of tension. The effect of tensile frequency on the mechanotransduction of PDLSCs is not clear. The current study aimed to determine the effect of different tensile frequencies on the osteogenic differentiation of PDLSCs and to identify important mechano-sensitivity genes.

Methods

Human PDLSCs were isolated, identified, and subjected to cyclic equibiaxial tensile strain of 12% at different frequencies of 0.1 Hz, 0.5 Hz, 0.7 Hz, or static cultures. Osteogenic differentiation of PDLSCs was assessed by using Western blotting. High-throughput sequencing was used to identify differential mRNA expression. Short time-series expression miner (STEM) was utilized to describe the frequency patterns of the mRNAs. The functions and enriched pathways were identified, and the hub genes were identified and validated.

Results

We found that the osteoblastic differentiation capacity of PDLSCs increased with tensile frequency in the range of 0.1–0.7 Hz. Eight frequency-tendency gene expression profiles were identified to be statistically significant. Tensile frequency-specific expressed genes, such as SALL1 and EYA1, which decreased with the increase in tensile frequency, were found.

Conclusion

The osteoblastic differentiation of PDLSCs under mechanical tensile force is frequency dependent. EYA1 and SALL1 were identified as potential important tensile frequency-sensitive genes, which may contribute to the cyclic tension-induced osteogenic differentiation of PDLSCs in a frequency-dependent manner.

TNF-α sculpts a maturation process in vivo by pruning tolerogenic dendritic cells

It remains unclear how the pro-immunogenic maturation of conventional dendritic cells (cDCs) abrogates their tolerogenic functions. Here, we report that the loss of tolerogenic functions depends on the rapid death of BTLAhi cDC1s, which, in the steady state, are present in systemic peripheral lymphoid organs and promote tolerance that limits subsequent immune responses. A canonical inducer of maturation, lipopolysaccharide (LPS), initiates a burst of tumor necrosis factor alpha (TNF-α) production and the resultant acute death of BTLAhi cDC1s mediated by tumor necrosis factor receptor 1. The ablation of these individual tolerogenic cDCs is amplified by TNF-α produced by neighboring cells. This loss of tolerogenic cDCs is transient, accentuating the restoration of homeostatic conditions through biological turnover of cDCs in vivo. Therefore, our results reveal that the abrogation of tolerogenic functions during an acute immunogenic maturation depends on an ablation of the tolerogenic cDC population, resulting in a dynamic remodeling of the cDC functional landscape.

Clinical Significance of BTLA and HVEM Expression on Circulating CD4+ T and CD8+ T Cells in Chronic Hepatitis B Virus Infection

In this study, B and T lymphocyte attenuator (BTLA) and herpesvirus entry mediator (HVEM) expression on the surface of circulating CD4⁺ T and CD8⁺ T cells of patients with chronic hepatitis B (CHB) was investigated to explore their relationship with hepatitis B virus (HBV) clinical parameters. Both BTLA and HVEM were significantly upregulated on CD4⁺ T and CD8⁺ T cells of CHB patients compared with healthy controls (p < 0.01). Intriguingly, in CHB patients, the percentage of BTLA expression was positively correlated with that of HVEM (CD4⁺ T cells: r = 0.5461, p < 0.001 and CD8⁺ T cells: r = 0.4206, p < 0.01). Moreover, the percentage of BTLA expression was positively correlated with the levels of aspartate aminotransferase (AST) (CD4⁺ T cells: r = 0.3136, p < 0.05 and CD8⁺ T cells: r = 0.3159, p < 0.05) and alanine aminotransaminase (ALT) (CD4⁺ T cells: r = 0.3177, p < 0.05 and CD8⁺ T cells: r = 0.3311, p < 0.05). At the same time, the percentage of HVEM expression was also positively correlated with AST levels (CD4⁺ T cells: r = 0.3721, p < 0.05 and CD8⁺ T cells: r = 0.3325, p < 0.05) and ALT (CD4⁺ T cells: r = 0.3689, p < 0.05 and CD8⁺ T cells: r = 0.3476, p < 0.05). However, the percentage of BTLA and HVEM expression did not show significant relevance to HBV viral load. Further study demonstrated that BTLA inhibitory signaling could significantly inhibit T cell proliferation, activation, and cytokine production under optimal T cell receptor signaling (p < 0.05). Thereby, our findings indicate that the increased BTLA and HVEM expression on the surface of CD4⁺ and CD8⁺ T cells might represent a certain clinical significance and be involved in CHB progression during T cell exhaustion.

Circulating LIGHT (TNFSF14) and Interleukin-18 Levels in Sepsis-Induced Multi-Organ Injuries

The novel therapeutic target cytokine LIGHT (TNFSF14) was recently shown to play a major role in COVID-19-induced acute respiratory distress syndrome (ARDS). This study aims to investigate the associations of plasma LIGHT and another potentially targetable cytokine, interleukin-18 (IL-18), with ARDS, acute hypoxic respiratory failure (AHRF), or acute kidney injury (AKI), caused by non-COVID-19 viral or bacterial sepsis. A total of 280 subjects diagnosed with sepsis, including 91 cases with sepsis triggered by viral infections, were investigated in this cohort study. Day 0 plasma LIGHT and IL-18, as well as 59 other biomarkers (cytokines, chemokines, and acute-phase reactants) were measured by sensitive bead immunoassay and associated with symptom severity. We observed significantly increased LIGHT level in both bacterial sepsis patients (p = 1.80 × 10⁻⁵) and patients with sepsis from viral infections (p = 1.78 × 10⁻³). In bacterial sepsis, increased LIGHT level was associated with ARDS, AKI, and higher Apache III scores, findings also supported by correlations of LIGHT with other biomarkers of organ failure. IL-18 levels were highly variable across individuals and consistently correlated with Apache III scores, mortality, and AKI in both bacterial and viral sepsis. There was no correlation between LIGHT and IL-18. For the first time, we demonstrate independent effects of LIGHT and IL-18 in septic organ failure. The association of plasma LIGHT with AHRF suggests that targeting the pathway warrants exploration, and ongoing trials may soon elucidate whether this is beneficial. Given the large variance of plasma IL-18 among septic subjects, targeting this pathway requires precise application.

Immune checkpoints and the multiple faces of B cells in systemic lupus erythematosus

PURPOSE OF REVIEW

B-lymphocytes are crucial in the pathogenesis of systemic lupus erythematosus (SLE), including autoantibody production, antigen presentation, co-stimulation, and cytokine secretion. Co-stimulatory and co-inhibitory molecules control interactions between B and T cells during an inflammatory response, which is essential for an appropriate host protection and maintenance of self-tolerance. Here, we review recent findings about checkpoint molecules and SLE B cells including their potential therapeutic implications and experiences from clinical trials.

RECENT FINDINGS

Most prominent checkpoint molecules involved in pathologic B and T cell interaction in SLE are CD40/CD40L and inducible co-stimulator/ICOSL, both also intimately involved in the formation of germinal centers and ectopic lymphoid tissue. Dysregulations of inhibitory checkpoint molecules, like programmed death-1/programmed death-ligand 1 and B- and T-lymphocyte attenuator have been suggested to impair B cell functions in SLE recently.

SUMMARY

Accumulating evidence indicates that dampening immune responses by either blocking co-activating signals or enhancing co-inhibitory signals in different cell types is a promising approach to treat autoimmune diseases to better control active disease but may also allow resolution of chronic autoimmunity.

Redefining the Role of Lymphotoxin Beta Receptor in the Maintenance of Lymphoid Organs and Immune Cell Homeostasis in Adulthood

Lymphotoxin beta receptor (LTβR) is a promising therapeutic target in autoimmune and infectious diseases as well as cancer. Mice with genetic inactivation of LTβR display multiple defects in development and organization of lymphoid organs, mucosal immune responses, IgA production and an autoimmune phenotype. As these defects are imprinted in embryogenesis and neonate stages, the impact of LTβR signaling in adulthood remains unclear. Here, to overcome developmental defects, we generated mice with inducible ubiquitous genetic inactivation of LTβR in adult mice (iLTβR^Δ/Δ mice) and redefined the role of LTβR signaling in organization of lymphoid organs, immune response to mucosal bacterial pathogen, IgA production and autoimmunity. In spleen, postnatal LTβR signaling is required for development of B cell follicles, follicular dendritic cells (FDCs), recruitment of neutrophils and maintenance of the marginal zone. Lymph nodes of iLTβR^Δ/Δ mice were reduced in size, lacked FDCs, and had disorganized subcapsular sinus macrophages. Peyer`s patches were smaller in size and numbers, and displayed reduced FDCs. The number of isolated lymphoid follicles in small intestine and colon were also reduced. In contrast to LTβR^-/- mice, iLTβR^Δ/Δ mice displayed normal thymus structure and did not develop signs of systemic inflammation and autoimmunity. Further, our results suggest that LTβR signaling in adulthood is required for homeostasis of neutrophils, NK, and iNKT cells, but is dispensable for the maintenance of polyclonal IgA production. However, iLTβR^Δ/Δ mice exhibited an increased sensitivity to C. rodentium infection and failed to develop pathogen-specific IgA responses. Collectively, our study uncovers new insights of LTβR signaling in adulthood for the maintenance of lymphoid organs, neutrophils, NK and iNKT cells, and IgA production in response to mucosal bacterial pathogen.

Associations between CD160 polymorphisms and autoimmune thyroid disease: a case-control study

BACKGROUND

Recent researches suggest that the CD160/HVEM/LIGHT/BTLA signaling pathway may contribute to the pathogeneses of autoimmune diseases, but the relationship between CD160 polymorphisms and autoimmune thyroid disease (AITD) has not been reported yet. This study aimed to evaluate the associations between CD160 polymorphisms and AITD.

METHODS

A total of 1017 patients with AITD (634 Graves' disease and 383 Hashimoto's thyroiditis) and 856 unrelated healthy controls were recruited into our study. Odds ratios (ORs) with 95% confidence interval (95%CI) were calculated through logistic regression analyses. The CD160 SNPs were detected using Hi-SNP high-throughput genotyping.

RESULTS

There was a statistically significant difference between Graves' disease patients and the control group with respect to both the genotype distribution (P = 0.014) and allele frequency of rs744877 (P = 0.034). A significant association of CD160 rs744877 with AITD was observed before adjusted age and gender under a dominant model (OR = 0.79, 95%CI 0.66-0.95; P = 0.013) and an additive model (OR = 0.77, 95%CI 0.64-0.94, P = 0.008), and was also observed after adjusted age and gender under a dominant model (OR = 0.78, 95%CI 0.65-0.95; P = 0.011) and an additive model (OR = 0.76, 95%CI 0.63-0.93, P = 0.007). A significant association of rs744877 with Graves' disease was observed under an allele model (OR = 0.84, 95%CI 0.71-0.98, P = 0.027), a dominant model (OR = 0.74, 95%CI 0.60-0.91; P = 0.005), and an additive model (OR = 0.72, 95%CI 0.58-0.90, P = 0.004). Multivariate logistic regression analyses suggested that the association remained significant after adjustment for age and gender. However, rs744877 was not related to Hashimoto's thyroiditis. Furthermore, CD160 rs3766526 was not significantly related to either Graves' disease or Hashimoto's thyroiditis.

CONCLUSION

This is the first identification of the association of CD160 rs744877 with Graves' disease. Our findings add new data to the genetic contribution to Graves' disease susceptibility and support the crucial role of the CD160/HVEM/LIGHT/BTLA pathway in the pathogenesis of Graves' disease.

The Role of B and T Lymphocyte Attenuator in Respiratory System Diseases

B and T lymphocyte attenuator (BTLA), an immunomodulatory molecule widely expressed on the surface of immune cells, can influence various signaling pathways and negatively regulate the activation and proliferation of immune cells by binding to its ligand herpes virus entry mediator (HVEM). BTLA plays an important role in immunoregulation and is involved in the pathogenesis of various respiratory diseases, including airway inflammation, asthma, infection, pneumonia, acute respiratory distress syndrome and lung cancer. In recent years, some studies have found that BTLA also has played a positive regulatory effect on immunity system in the occurrence and development of respiratory diseases. Since severe pulmonary infection is a risk factor for sepsis, this review also summarized the new findings on the role of BTLA in sepsis.

Elevation of Circulating LIGHT (TNFSF14) and Interleukin-18 Levels in Sepsis-Induced Multi-Organ Injuries

Objective

The cytokines, LIGHT (TNFSF14) and Interleukin-18 (IL-18), are two important therapeutic targets due to their central roles in the function of activated T cells and inflammatory injury. LIGHT was recently shown to play a major role in COVID19 induced acute respiratory distress syndrome (ARDS), reducing mortality and hospital stay. This study aims to investigate the associations of LIGHT and IL-18 with non-COVID19 related ARDS, acute hypoxic respiratory failure (AHRF) or acute kidney injury (AKI), secondary to viral or bacterial sepsis.

Research Design and Methods

A cohort of 280 subjects diagnosed with sepsis, including 91 cases with sepsis triggered by viral infections, were investigated in this study and compared to healthy controls. Serum LIGHT, IL-18, and 59 other biomarkers (cytokines, chemokines and acute-phase reactants) were measured and associated with symptom severity.

Results

ARDS was observed in 36% of the patients, with 29% of the total patient cohort developing multi-organ failure (failure of two or more organs). We observed significantly increased LIGHT level (>2SD above mean of healthy subjects) in both bacterial sepsis patients (P=1.80E-05) and patients with sepsis from viral infections (P=1.78E-03). In bacterial sepsis, increased LIGHT level associated with ARDS, AKI and higher Apache III scores, findings also supported by correlations of LIGHT with other biomarkers of organ failures, suggesting LIGHT may be an inflammatory driver. IL-18 levels were highly variable across individuals, and consistently correlated with Apache III scores, mortality, and AKI, in both bacterial and viral sepsis.

Conclusions

For the first time, we demonstrate independent effects of LIGHT and IL-18 in septic organ failures. LIGHT levels are significantly elevated in non-COVID19 sepsis patients with ARDS and/or multi-organ failures suggesting that anti-LIGHT therapy may be effective therapy in a subset of patients with sepsis. Given the large variance of plasma IL-18 among septic subjects, targeting this pathway raises opportunities that require a precision application.

Genomic and functional evaluation of TNFSF14 in multiple sclerosis susceptibility

Among multiple sclerosis (MS) susceptibility genes, the strongest non-human leukocyte antigen (HLA) signal in the Italian population maps to the TNFSF14 gene encoding LIGHT, a glycoprotein involved in dendritic cell (DC) maturation. Through fine-mapping in a large Italian dataset (4,198 patients with MS and 3,903 controls), we show that the TNFSF14 intronic SNP rs1077667 is the primarily MS-associated variant in the region. Expression quantitative trait locus (eQTL) analysis indicates that the MS risk allele is significantly associated with reduced TNFSF14 messenger RNA levels in blood cells, which is consistent with the allelic imbalance in RNA-Seq reads (P < 0.0001). The MS risk allele is associated with reduced levels of TNFSF14 gene expression (P < 0.01) in blood cells from 84 Italian patients with MS and 80 healthy controls (HCs). Interestingly, patients with MS are lower expressors of TNFSF14 compared to HC (P < 0.007). Individuals homozygous for the MS risk allele display an increased percentage of LIGHT-positive peripheral blood myeloid DCs (CD11c⁺, P = 0.035) in 37 HCs, as well as in in vitro monocyte-derived DCs from 22 HCs (P = 0.04). Our findings suggest that the intronic variant rs1077667 alters the expression of TNFSF14 in immune cells, which may play a role in MS pathogenesis.

Immune Checkpoints in Pediatric Solid Tumors: Targetable Pathways for Advanced Therapeutic Purposes

The tumor microenvironment (TME) represents a complex network between tumor cells and a variety of components including immune, stromal and vascular endothelial cells as well as the extracellular matrix. A wide panel of signals and interactions here take place, resulting in a bi-directional modulation of cellular functions. Many stimuli, on one hand, induce tumor growth and the spread of metastatic cells and, on the other hand, contribute to the establishment of an immunosuppressive environment. The latter feature is achieved by soothing immune effector cells, mainly cytotoxic T lymphocytes and B and NK cells, and/or through expansion of regulatory cell populations, including regulatory T and B cells, tumor-associated macrophages and myeloid-derived suppressor cells. In this context, immune checkpoints (IC) are key players in the control of T cell activation and anti-cancer activities, leading to the inhibition of tumor cell lysis and of pro-inflammatory cytokine production. Thus, these pathways represent promising targets for the development of effective and innovative therapies both in adults and children. Here, we address the role of different cell populations homing the TME and of well-known and recently characterized IC in the context of pediatric solid tumors. We also discuss preclinical and clinical data available using IC inhibitors alone, in combination with each other or administered with standard therapies.

Investigation of IL-4, IL-10, and HVEM polymorphisms with esophageal squamous cell carcinoma: a case-control study involving 1929 participants

It is believed that an individual’s hereditary factors may be involved in the development of esophageal cancer (EC). The present study recruited 721 esophageal squamous cell carcinoma (ESCC) cases and 1208 controls and explored the roles of single nucleotide polymorphisms (SNPs) in the interleukin-4 (IL-4), IL-10, and herpesvirus entry mediator (HVEM) genes in contributing to ESCC risk. IL-4, IL-10, and HVEM SNPs were analyzed by employing an SNPscan method. After adjustment for body mass index (BMI), smoking, drinking, age and gender, we identified that the rs2070874 T>C locus in IL-4 gene decreased the risk of ESCC (CC vs. TT: P=0.008; CC vs. TT/TC: P=0.010). After a stratified analysis, we suggested that the IL-4 rs2070874 T>C variants might be a protective factor for ESCC in male, ≥63 years old, never smoking, drinking and BMI < 24 kg/m² subgroups. In addition, we identified that the rs2243263 G>C polymorphism in IL-4 gene was a risk factor for ESCC development in the BMI ≥ 24 kg/m² subgroup (GC vs. GG: P=0.030 and GC/CC vs. GG: P=0.018). We identified an association of the IL-4 rs2070874 T>C SNP with the decreased susceptibility of ESCC in stage I/II subgroup. Finally, we found an association of the IL-10 rs1800872 T>G SNP with a worse differentiation (TG vs. TT: P=0.048 and GG/TG vs. TT: P=0.032). In conclusion, the findings indicate a potential importance of IL-4 rs2070874 T>C, IL-4 rs2243263 G>C and IL-10 rs1800872 T>G SNPs in the development of ESCC.

Roles of BTLA in Immunity and Immune Disorders

B and T lymphocyte attenuator (BTLA) is one of the most important cosignaling molecules. It belongs to the CD28 superfamily and is similar to programmed cell death-1 (PD-1) and cytotoxic T lymphocyte associated antigen-4 (CTLA-4) in terms of its structure and function. BTLA can be detected in most lymphocytes and induces immunosuppression by inhibiting B and T cell activation and proliferation. The BTLA ligand, herpesvirus entry mediator (HVEM), does not belong to the classic B7 family. Instead, it is a member of the tumor necrosis factor receptor (TNFR) superfamily. The association of BTLA with HVEM directly bridges the CD28 and TNFR families and mediates broad and powerful immune effects. Recently, a large number of studies have found that BTLA participates in numerous physiopathological processes, such as tumor, inflammatory diseases, autoimmune diseases, infectious diseases, and transplantation rejection. Therefore, the present work aimed to review the existing knowledge about BTLA in immunity and summarize the diverse functions of BTLA in various immune disorders.

Immune checkpoints in sepsis: New hopes and challenges

Sepsis is a life-threatening syndrome with a high incidence and a weighty economic burden. The cytokines storm in the early stage and the state of immunosuppression in the late stage contribute to the mortality of sepsis. Immune checkpoints expressed on lymphocytes and APCs, including CD28, CTLA-4, CD80, CD86, PD-1 and PD-L1, CD40 and CD40L, OX40 and OX40L, 4-1BB and 4-1BBL, BTLA, TIM family, play significant roles in the pathogenesis of sepsis through regulating the immune disorder. The specific therapies targeting immune checkpoints exhibit great potentials in the animal and preclinical studies, and further clinical trials are planning to implement. Here, we review the current literature on the roles played by immune checkpoints in the pathogenesis and treatment of sepsis. We hope to provide further insights into this novel immunomodulatory strategy.

A Genetic Variant of the BTLA Gene is Related to Increased Risk and Clinical Manifestations of Breast Cancer in Chinese Women

BACKGROUND

B and T lymphocyte attenuator (BTLA), an immunoinhibitory receptor, is shown to suppress the lymphocyte activation. Several studies addressed the relationship between the BTLA rs1982809 polymorphism and the risk of cancer.

PATIENTS AND METHODS

To identify the effects of this polymorphism on the risk of breast cancer (BC), this study examined Chinese women from China, Jiangsu Province. This study involved 324 patients with BC and 412 controls.

RESULTS

We observed that the BTLA rs1982809 polymorphism elevated the risk of BC. A similar finding was also shown in the subgroups of premenopausal women and those aged < 55 years old. In addition, this polymorphism was correlated with the estrogen receptor status, C-erbB-2 status, Ki-67 status, TNM stage, and tumor size of patients with BC.

CONCLUSIONS

Collectively, the BTLA rs1982809 polymorphism shows a significant association with elevated risk and clinical features of BC in Chinese women. Further studies involving other races are urgently needed to replicate these findings.

Involvement of lncRNAs in celiac disease pathogenesis

Celiac disease (CD) is an immune-mediated disease that develops in genetically susceptible individuals upon gluten exposure. Human Leukocyte Antigen (HLA) genes in the Major Histocompatibility Complex (MHC) have been described to represent the 40% of the genetic risk to develop CD. Aiming to gain understanding of the genetic involvement in CD, high throughput studies have been performed, revealing that many CD-associated variants are located in non-coding regions, hindering the study of the functional implications of these single nucleotide polymorphisms (SNPs). In the last decade, long non-coding RNAs (lncRNAs) have been described to be influenced by disease-associated SNPs and to drive many important mechanisms involved in the development of inflammatory diseases. Here we describe the lncRNAs identified and characterized in the context of celiac disease and highlight the importance of the study of these molecules in inflammatory and autoimmune disorders.

Natural and Induced Tolerogenic Dendritic Cells

Dendritic cells (DCs) are highly susceptible to extrinsic signals that modify the functions of these crucial APCs. Maturation of DCs induced by diverse proinflammatory conditions promotes immune responses, but certain signals also induce tolerogenic functions in DCs. These "induced tolerogenic DCs" help to moderate immune responses such as those to commensals present at specific anatomical locations. However, also under steady-state conditions, some DCs are characterized by inherent tolerogenic properties. The immunomodulatory mechanisms constitutively present in such "natural tolerogenic DCs" help to promote tolerance to peripheral Ags. By extending tolerance initially established in the thymus, these functions of DCs help to regulate autoimmune and other immune responses. In this review we will discuss the mechanisms and functions of natural and induced tolerogenic DCs and offer further insight into how their possible manipulations may ultimately lead to more precise treatments for various immune-mediated conditions and diseases.

Clinical significance of herpes virus entry mediator expression in hepatitis B virus-related hepatocellular carcinoma

Herpes virus entry mediator (HVEM) is overexpressed in several malignancies, including hepatocellular carcinoma (HCC). However, to the best of our knowledge, the clinical significance of HVEM in hepatitis B virus (HBV)-related HCC remains unclear. Thus, the present study aimed to explore the clinical significance of HVEM in HBV-related HCC. In the present study, HVEM expression was evaluated in HCC cell lines and HCC frozen samples. The prognostic value of HVEM was assessed in a cohort of 221 patients with HBV-related HCC, following radical resection. B- and T-lymphocyte attenuator (BTLA) expression in subsets of CD8⁺ T cells was determined via flow cytometry analysis. The results demonstrated high HVEM expression in HCC cell lines, and in HCC tissues compared with paired non-cancerous liver tissues. HVEM expression was demonstrated to be significantly associated with tumor encapsulation and vascular invasion. Furthermore, tumor HVEM status was significantly associated with infiltration of regulatory T cells, but not with CD8⁺ T cells. Notably, high HVEM expression in HCC was determined to be an independent predictor of an unfavorable outcome of patients with HCC following radical resection. Higher BTLA expression (the receptor of HVEM) was observed in both HCC-infiltrating CD8⁺ effector memory (CCR7^- CD45RA^-) and CD45RA⁺ effector memory (CCR7^- CD45RA⁺) T cells in HCC tissues and blood compared with those in paired peritumor tissues or peripheral blood. Taken together, the results of the present study suggest that HVEM may serve a critical role in HBV-related HCC, most likely by promoting tumor progression and tumor immune evasion, thus the HVEM/BLTA signaling pathway may be a potential target in tumor immunotherapy.

Association of BTLA rs1982809 polymorphism with lung cancer risk in Tunisian population

B and T lymphocyte attenuator (BTLA) is an immune-inhibitory receptor that negatively regulates the lymphocyte activation. A few studies have been devoted to the relationship between BTLA gene variations and cancer's risk. It has been essentially demonstrated to be involved in increasing cancer risk in chronic lymphocyte leukaemia, renal cell carcinoma, breast and colorectal cancer predispositions in Asian population. The aim of this study was to evaluate the association between BTLA gene polymorphisms and the risk of lung cancer in the Tunisian population. In a case-control study, three BTLA single-nucleotide polymorphism (SNP): rs1982809 (A > G), rs9288952 (G > A) and rs9288953(C > T) were genotyped with the use of TaqMan probes in 169 lung cancer patients and in 300 controls. The rs1982809 SNP was significantly associated with an increased risk of lung cancer compared with controls in codominant and dominant models. The heterozygous rs1982809-AG genotype carriers had a higher risk of developing lung cancer when compared to AA genotype carriers in Tunisian population (OR (95%CI) = 1.63 (1.09-2.42), p = .01]. The AG genotype is an important risk factor associated with lymphatic invasion (OR = 3.71) and large-sized lung tumour (OR = 1.80). It is also a risk factor for the development of an adenocarcinoma subtype (OR = 2.08). However, the BTLA rs9288953 and rs9288952 SNPs were not associated with susceptibility for lung cancer (p > .05). Haplotype comparison did not show any significant association in our research. For the survival analysis, there was no impact of BTLA SNPs on the mortality risk associated to lung cancer in Tunisian patients. The current study is the first to demonstrate an association between BTLA rs1982809 polymorphism and an increased lung cancer risk in the Tunisian population.

Lung-resident mesenchymal stem cells regulated the inflammatory responses in innate and adaptive immune cells through HVEM-BTLA pathway during ARDS

Acute respiratory distress syndrome (ARDS) is an organ failure syndrome caused by overactivation of the immune system. Mesenchymal stem cells (MSCs) have been found to be effective in ARDS therapy due to their excellent immunomodulatory abilities; however, people are concerned about the safety of infusing exogenous cells. We found that rat lung-resident mesenchymal stem cells (LRMSCs) (Sca-1⁺CD45^-CD31^-) played important roles in regulating inflammation in the lungs during the pathogenesis of ARDS. LRMSCs could regulate the production of cytokines (TNF-α, MCP-1, and IL-10) by both innate and adaptive immune cells following LPS stimulation in vivo or in vitro. We also found that Herpes Virus Entry Mediator (HVEM) expression in LRMSCs enhanced the immunomodulatory ability of LRMSCs, and expression of the HVEM ligand B and T Lymphocyte Attenuator (BTLA) in innate and adaptive immune cells was required. The clarification of this immunoregulatory mechanism may provide evidence for ARDS therapy mediated by mobilizing endogenous MSCs in the future.

The risk of rheumatoid arthritis among patients with inflammatory bowel disease: a systematic review and meta-analysis

Background

Studies have suggested that patients with inflammatory bowel disease (IBD) have an increased risk of rheumatoid arthritis (RA). However, the available data on this association are inconsistent. This meta-analysis aimed to determine the association between IBD and the risk of RA.

Methods

Observational studies investigating the RA risk among patients with IBD (Crohn disease (CD) and/or ulcerative colitis (UC)) were searched in PubMed, Embase, and Web of Science from the date of inception to December 2019. The methodological quality of the included studies was assessed using the Newcastle-Ottawa Scale. Relative risks (RRs) and corresponding 95% confidential intervals (CIs) were pooled with a random-effects model. Heterogeneity was evaluated using I² statistics while publication bias was determined using Begg’s and Egger’s tests. Subgroup and sensitivity analyses were performed.

Results

A total of three cohort studies, three cross-sectional studies, and two case-control studies were included in the meta-analyses. Compared to the non-IBD control or general population, there was a significantly higher risk of RA among patients with IBD (RR = 2.59; 95% CI: 1.93–3.48). Moreover, both CD (RR = 3.14; 95% CI: 2.46–4.01) and UC (RR = 2.29; 95% CI: 1.76–2.97) were associated with a significantly increased risk of RA. However, heterogeneity was substantial across studies and the subgroup analyses failed to identify the potential source of heterogeneity.

Conclusions

Patients with IBD have a greater risk of developing RA. Rheumatologists should be consulted when patients with IBD present with undifferentiated joint complaints. However, more prospective cohort studies are needed to validate these results.

Immune Checkpoint Axes Are Dysregulated in Patients With Alcoholic Hepatitis

Alcoholic hepatitis (AH) is a severe inflammatory liver disease that develops in some heavy drinkers. The immune system in patients with AH is hyperactive and yet dysfunctional. Here, we investigated whether this immune-dysregulated state is related to the alcoholic impact on immune checkpoints (ICPs). We used multiplex immunoassays and enzyme-linked immunosorbent assay to quantify plasma levels of 18 soluble ICPs (sICPs) from 81 patients with AH, 65 heavy drinkers without liver diseases (HDCs), and 39 healthy controls (HCs) at baseline, 33 patients with AH and 32 HDCs at 6-month follow-up, and 18 patients with AH and 29 HDCs at 12-month follow-up. We demonstrated that baseline levels of 6 sICPs (soluble T-cell immunoglobulin and mucin domain 3 [sTIM-3], soluble cluster of differentiation [sCD]27, sCD40, soluble Toll-like receptor-2 [sTLR-2], soluble herpesvirus entry mediator [sHVEM], and soluble lymphotoxin-like inducible protein that competes with glycoprotein D for herpes virus entry on T cells [sLIGHT]) were up-regulated, while 11 sICPs (soluble B- and T-lymphocyte attenuator [sBTLA], sCD160, soluble cytotoxic T-lymphocyte-associated protein 4 [sCTLA-4], soluble lymphocyte-activation gene 3 [sLAG-3], soluble programmed death 1 [sPD-1], sPD ligand 1 [sPD-L1], sCD28, soluble glucocorticoid-induced tumor necrosis factor receptor-related protein [sGITR], sGITR ligand [sGITRL], sCD80, and inducible T-cell costimulator [sICOS]) were down-regulated in patients with AH compared to HDCs. The up-regulated sICPs except sLIGHT and down-regulated sCD80, sCD160, sCTLA-4, and sLAG-3 correlated positively or negatively with AH disease severity, bacterial translocation, and inflammatory factors. At follow-up, abstinent patients with AH still had higher levels of several sICPs compared to HDCs. We also compared expression of 10 membrane-bound ICPs (mICPs) on peripheral blood mononuclear cells (PBMCs) from patients with AH and HCs by flow cytometry and found that several mICPs were dysregulated on blood cells from patients with AH. The function and regulation of sICPs and mICPs were studied using PBMCs from patients with AH and HCs. Recombinant sHVEM affected tumor necrosis factor (TNF)-α and interferon-γ production by T cells from patients with AH and HCs. Conclusion: Both sICPs and mICPs were dysregulated in patients with AH, and alcohol abstinence did not fully reverse these abnormalities. The HVEM axis plays a role in regulating T-cell function in patients with AH.

Increased expression of the TNF superfamily member LIGHT/TNFSF14 and its receptors (HVEM and LTßR) in patients with systemic sclerosis

OBJECTIVES

This study aimed to assess the potential role of the TNF superfamily member lymphocyte T-related inducible ligand that competes for glycoprotein D binding to herpesvirus entry mediator on T cells (LIGHT) in SSc through evaluation of: skin expression of LIGHT and its receptors, herpesvirus entry mediator and lymphotoxin ß-related receptor, and serum concentration of LIGHT in SSc patients.

METHODS

Expression of LIGHT and its receptors was investigated by immunohistochemistry and evaluated semi-quantitatively in skin biopsies from 19 SSc patients and 9 healthy controls. Serum levels of LIGHT were measured using ELISA in 329 patients with SSc and 50 control subjects.

RESULTS

Expression of LIGHT and both receptors was higher in SSc patients compared with controls (P < 0.05 for all comparisons). Patients with early SSc (⩽ 3 years from the first non-Raynaud's phenomenon symptom) showed higher expression of LIGHT and herpesvirus entry mediator compared with patients with longer disease duration (P < 0.05 for both comparisons). The mean serum concentration of LIGHT was significantly higher in SSc patients compared with the controls (P < 0.05). High serum concentration of LIGHT was associated with male sex, presence of digital ulcers, muscle involvement (defined by elevated serum creatine kinase levels), steroid treatment and lack of ACA. However, in multivariate regression analysis only presence of digital ulcers and creatine kinase elevation were independently associated with serum concentration of LIGHT.

CONCLUSION

These data provide the first evidence of overexpression of LIGHT and its receptors in SSc and suggest that the LIGHT axis might contribute to the pathogenesis of SSc. Increased serum concentrations of LIGHT seem to reflect vascular injury in SSc.

The Co-inhibitor BTLA Is Functional in ANCA-Associated Vasculitis and Suppresses Th17 Cells

Objectives: The activation and inhibition of T-cells has been well-studied under physiological conditions. Co-inhibition is an important mechanism to keep effector T-cells in check. Co-inhibitors mediate peripheral self-tolerance and limit the immune response. Dysfunctional co-inhibition is associated with loss of T-cell regulation and induction of autoimmunity. Therefore, we investigated the co-inhibitor B- and T-Lymphocyte attenuator (BTLA) in ANCA-associated vasculitis (AAV). Methods: Fifty-six AAV patients and 32 healthy controls (HC) were recruited. Flow cytometry was performed to investigate the expression of BTLA on T-cells. Double negative T-cells were defined as CD3⁺CD4^-CD8^-. To assess the functionality of BTLA, CFSE-labeled T-cells were stimulated in presence or absence of an agonistic anti-BTLA antibody. In addition, impact of BTLA-mediated co-inhibition on Th17 cells was studied. Results: AAV patients in remission had a decreased expression of BTLA on double negative T-cells (CD3⁺CD4^-CD8^-). On all other subtypes of T-cells, expression of BTLA was comparable to healthy controls. TCR-independent stimulation of T-cells resulted in down-regulation of BTLA on Th cells in AAV and HC, being significantly lower in HC. Co-inhibition via BTLA led to suppression of T-cell proliferation in AAV as well as in HC. As a result of BTLA mediated co-inhibition, Th17 cells were suppressed to the same extent in AAV and HC. Conclusion: BTLA expression is altered on double negative T-cells but not on other T-cell subsets in quiescent AAV. BTLA-induced co-inhibition has the capacity to suppress Th17 cells and is functional in AAV. Thus, BTLA-mediated co-inhibition might be exploited for future targeted therapies in AAV.

Rs1982809 is a functional biomarker for the prognosis of severe post-traumatic sepsis and MODs

BTLA is a useful biomarker to characterize the immune states of sepsis patients. We investigated the association between genetic variations of BTLA and morbidity of sepsis and MODS in severe traumatic patient. Three tag single nucleotide polymorphisms of BTLA were genotyped in 562 severe trauma patients. To further elucidate the mechanism, mRNA stability, BTLA 3ʹ-UTR activity, and its expression on T lymphocytes were measured. Only rs1982809 which located in 3ʹ-UTR of BTLA showed a significant clinical relevance with the incidence rate of sepsis and MOD scores. The sepsis incidence and MOD score of rs1982809 CC genotype carriers were higher than TT carriers. The percentage of circulating BTLA + CD4 + CD3 +  T lymphocytes was markedly lower in CC genotype carriers. Luciferase activity in plasmids containing C allele was lower than that of T allele. Thus, the differential expression of BTLA on T lymphocytes might be caused by the different 3ʹ-UTR activity induced by rs1982809 T/C. Therefore, rs1982809 is a useful clinical biomarker in the prognosis evaluating of sepsis and subsequent MODS. Moreover, it is also a functional single nucleotide polymorphism affecting the activity of BTLA 3ʹ-UTR and the expression of BTLA in peripheral blood T lymphocytes.

Impact statement

This work is useful in the field of genetic mechanism of severe post-traumatic complications, as it provides important evidence for the influence of BTLA gene polymorphism on sepsis and MODS susceptibility. The results are useful and of importance because rs1982809 is a useful clinical biomarker in the prognosis evaluating of sepsis and subsequent MODS. It is also a functional single nucleotide polymorphism affecting the activity of BTLA 3ʹ-UTR and the expression of BTLA in peripheral blood T lymphocytes.

BTLA Expression on Th1, Th2 and Th17 Effector T-Cells of Patients with Systemic Lupus Erythematosus Is Associated with Active Disease

An imbalanced T-cell homeostasis plays an important role in the pathogenesis of systemic lupus erythematosus (SLE). Co-stimulatory and co-inhibitory molecules regulate T-cell differentiation, survival, and cytokine production. B- and T-lymphocyte attenuator (BTLA) is a co-inhibitory molecule which negatively regulates T-cell activation. The aim of this study was to investigate BTLA expression on regulatory and effector CD4⁺ T-cells in SLE patients with and without lupus nephritis (LN) during active and inactive disease. Therefore, peripheral blood of forty-one SLE patients and twenty-one healthy controls (HC) was phenotypically analyzed. Next, ex vivo stimulated T-cells were analyzed for the expression of BTLA on Th1-, Th2-, and Th17-effector cells by flow cytometry. Renal involvement was defined as biopsy-proven LN. Disease activity was assessed by SLE disease activity index (SLEDAI). Percentages of peripheral unstimulated BTLA⁺ CD4⁺ T-cells were significantly decreased in SLE patients with active disease. However, ex vivo stimulated Th1, Th2, and Th17 effector T-cells, expressed increased percentages of BTLA expression in active disease. In contrast, the BTLA expression on CD4⁺CD25⁺⁺CD127⁻ regulatory T-cells was not significantly different. BTLA seems to be an important co-inhibitory molecule in the T-cell homeostasis of patients with systemic lupus erythematosus and crucial for disease activity.

BTLA/HVEM Signaling: Milestones in Research and Role in Chronic Hepatitis B Virus Infection

B- and T-lymphocyte attenuator (BTLA) is an immune-regulatory receptor, similar to CTLA-4 and PD-1, and is mainly expressed on B-, T-, and all mature lymphocyte cells. Herpes virus entry mediator (HVEM)-BTLA plays a critical role in immune tolerance and immune responses which are areas of intense research. However, the mechanisms of the BTLA and the BTLA/HVEM signaling pathway in human diseases remain unclear. This review describes the research milestones of BTLA and HVEM in chronological order and their role in chronic HBV infection.

Characterization of Sex Differences in Ocular Herpes Simplex Virus 1 Infection and Herpes Stromal Keratitis Pathogenesis of Wild-Type and Herpesvirus Entry Mediator Knockout Mice

Sex differences related to immune response and inflammation play a role in the susceptibility and pathogenesis of a variety of viral infections and disease (S. L. Klein, Bioessays 34:1050-1059, 2012, https://doi.org/10.1002/bies.201200099). Herpes simplex virus 1 (HSV-1) causes chronic inflammatory disease in the cornea, an immune-privileged tissue, resulting in irreversible damage and blindness in affected individuals (A. Rowe, A. St Leger, S. Jeon, D. K. Dhaliwal, et al., Prog Retin Eye Res 32:88-101, 2013, https://doi.org/10.1016/j.preteyeres.2012.08.002). Our research focuses on the role of herpesvirus entry mediator (HVEM) as an immune regulator during ocular HSV-1 infection. Mice lacking HVEM (HVEM knockout [KO] mice) exhibit lower levels of immune cell infiltrates and less severe ocular disease in the cornea than wild-type (WT) mice. As sex differences contribute to pathogenesis in many inflammatory diseases, we tested whether sex acts as a biological variable in the immune response to HSV-1 infection and herpes stromal keratitis (HSK) pathogenesis. Adult male and female WT and HVEM KO mice were inoculated with HSV-1 via corneal scarification and monitored daily for disease course. Viral titers were determined, and immune cell infiltrates were collected and analyzed. Our results indicated no significant differences in viral titers in tear film or affected tissues, in immune cell infiltration, or in clinical symptoms between males and females of either genotype. These results suggest that sex is not a significant biological variable in this experimental model and that male and female mice of the C57BL/6 background can be used similarly in studies of ocular HSV-1 pathogenesis.IMPORTANCE Sex hormones have come to be considered an important factor for the development of certain diseases only recently and as such should continue to be considered a biological variable. Ocular HSV-1, and the resulting HSK, is the leading cause of infectious blindness worldwide. We compared levels of ocular HSV-1 infection and pathogenesis in the two sexes and found no significance differences between male and female WT mice or HVEM KO mice.

The Tumor Necrosis Factor Family: Family Conventions and Private Idiosyncrasies

The tumor necrosis factor (TNF) cytokine family and the TNF/nerve growth factor (NGF) family of their cognate receptors together control numerous immune functions, as well as tissue-homeostatic and embryonic-development processes. These diverse functions are dictated by both shared and distinct features of family members, and by interactions of some members with nonfamily ligands and coreceptors. The spectra of their activities are further expanded by the occurrence of the ligands and receptors in both membrane-anchored and soluble forms, by "re-anchoring" of soluble forms to extracellular matrix components, and by signaling initiation via intracellular domains (IDs) of both receptors and ligands. Much has been learned about shared features of the receptors as well as of the ligands; however, we still have only limited knowledge of the mechanistic basis for their functional heterogeneity and for the differences between their functions and those of similarly acting cytokines of other families.

Increased expression of TNFRSF14 indicates good prognosis and inhibits bladder cancer proliferation by promoting apoptosis

Despite advances in management, bladder cancer remains a principal cause of cancer‑associated complications. Tumor necrosis factor receptor superfamily member 14 (TNFRSF14) is dysregulated in certain types of cancer; however, limited data are available on the expression and function of TNFRSF14 in bladder cancer. In the present study, the aim was to evaluate the expression and biological functions of TNFRSF14 in bladder cancer. Firstly, the expression levels of TNFRSF14 in bladder cancer tissue were examined using The Cancer Genome Atlas (TCGA) database. Secondly, reverse transcription‑quantitative polymerase chain reaction was utilized to investigate the expression levels of TNFRSF14 in the T24, SW780 and EJ‑M3 bladder cancer cell lines. Transfection and Cell Counting kit‑8 (CCK‑8) assay was used to evaluate whether TNFRSF14 overexpression or silencing would have an effect on cell proliferation of T24 and EJ‑M3 cells. In addition, TNFRSF14‑induced apoptotic cells were identified using Annexin V‑fluorescein isothiocyanate and propidium iodide staining. Western blot analysis was used to detect proteins associated with the phosphatidylinositol 3‑kinase pathway. According to the TCGA dataset, the expression levels TNFRSF14 were decreased in bladder cancer tissue compared with in normal control samples. Patients with bladder cancer exhibiting low expression levels of TNFRSF14 had a worse prognosis compared to those with high expression levels of TNFRSF14. Overexpression of TNFRSF14 in T24 cells led to increased apoptosis and inhibited cell proliferation in vitro. Western blotting demonstrated that TNFRSF14 overexpression increased the expression levels of caspase3‑p17 in T24 cells, but significantly decreased the expression levels of phosphorylated (p)‑protein kinase B (AKT) and P70 S6 kinase (P70). TNFRSF14 silencing in EJ‑M3 cells enhanced cell growth, inhibited cell apoptosis, increased the expression levels of p‑AKT and P70, and decreased the expression levels of caspase3‑p17. In conclusion, TNFRSF14 may serve a tumor suppressive role in bladder cancer by inducing apoptosis and suppressing proliferation, and act as a novel prognostic biomarker for bladder cancer.

Distinct Changes of BTLA and HVEM Expressions in Circulating CD4+ and CD8+ T Cells in Hepatocellular Carcinoma Patients

BTLA/HVEM (B and T lymphocyte attenuator/herpes virus entry mediator) pathways play a critical role in T cell suppression in tumor. However, its dynamic changes in different T cell subsets in peripheral blood and their clinical significance are largely unclear in cancer patients. In the current study, we showed distinct changes of BTLA and HVEM expressions on peripheral blood CD4⁺ and CD8⁺ T cells in patients with hepatocellular carcinoma (HCC); BTLA expression were significantly upregulated on circulating CD4⁺ but not CD8⁺ T cells. In sharp contrast, the levels of HVEM expression were significantly downregulated on circulating CD8⁺ but not CD4⁺ T cells. A strong positive correlation between BTLA expression on circulating CD4⁺ T cells and BTLA expression on autologous CD8⁺ counterparts was observed in healthy donors but absent in HCC patients. More importantly, we found that blockade of the BTLA/HVEM pathway increased IFN-γ production in both circulating CD4⁺ and CD8⁺ T cells. Collectively, our data suggested that the BTLA/HVEM pathway contributes to peripheral T cell suppression in HCC patients, and BTLA/HVEM may serve as attractive targets for HCC immunotherapy.