Cytosine-phosphate-guanosine-DNA induces CD274 expression in human B cells and suppresses T helper type 2 cytokine production in pollen antigen-stimulated CD4-positive cells

Gene Signatures and Associated Transcription Factors of Allergic Rhinitis: KLF4 Expression Is Associated with Immune Response

This study is aimed at investigating the potential molecular features of allergic rhinitis (AR) and identifying gene signatures and related transcription factors using transcriptome analysis and in silico datasets. Transcriptome profiles were obtained using three independent cohorts (GSE101720, GSE19190, and GSE46171) comprising healthy controls (HC) and patients with AR. The pooled dataset (n = 82) was used to identify the critical signatures of AR compared with HC. Subsequently, key transcription factors were identified by a combined analysis using transcriptome and in silico datasets. Gene ontology: bioprocess (GO: BP) analysis using differentially expressed genes (DEGs) revealed that immune response-related genes were significantly enriched in AR compared with HC. Among them, IL1RL1, CD274, and CD44 were significantly higher in AR patients. We also identified key transcription factors between HC and AR using the in silico dataset and found that AR samples frequently express KLF transcription factor 4 (KLF4), which regulates immune response-related genes including IL1RL1, CD274, and CD44 in human nasal epithelial cells. Our integrative analysis of transcriptomic regulation provides new insights into AR, which may help in developing precision management for patients with AR.

Allergen Immunotherapy: Current and Future Trends

Allergen immunotherapy (AIT) is the sole disease-modifying treatment for allergic rhinitis; it prevents rhinitis from progressing to asthma and lowers medication use. AIT against mites, insect venom, and certain kinds of pollen is effective. The mechanism of action of AIT is based on inducing immunological tolerance characterized by increased IL-10, TGF-β, and IgG4 levels and Treg cell counts. However, AIT requires prolonged schemes of administration and is sometimes associated with adverse reactions. Over the last decade, novel forms of AIT have been developed, focused on better allergen identification, structural modifications to preserve epitopes for B or T cells, post-traductional alteration through chemical processes, and the addition of adjuvants. These modified allergens induce clinical-immunological effects similar to those mentioned above, increasing the tolerance to other related allergens but with fewer side effects. Clinical studies have shown that molecular AIT is efficient in treating grass and birch allergies. This article reviews the possibility of a new AIT to improve the treatment of allergic illness.

Regulatory B Cell Therapy in Kidney Transplantation

In the context of kidney injury, the role of Bregs is gaining interest. In a number of autoimmune diseases, the number and/or the function of Bregs has been shown to be impaired or downregulated, therefore restoring their balance might be a potential therapeutic tool. Moreover, in the context of kidney transplantation their upregulation has been linked to tolerance. However, a specific marker or set of markers that define Bregs as a unique cell subset has not been found and otherwise multiple phenotypes of Bregs have been studied. A quest on the proper markers and induction mechanisms is now the goal of many researchers. Here we summarize the most recent evidence on the role of Bregs in kidney disease by describing the relevance of in vitro and in vivo Bregs induction as well as the potential use of Bregs as cell therapy agents in kidney transplantation.

Successful management of severe bronchial asthma exacerbated by anti-PD-L1 treatment: A report of two cases

Immune checkpoint inhibitors (ICIs) have been used for various carcinomas. However, immune-related adverse events have been observed. There have been few reports of treatment with biologics for severe bronchial asthma induced by ICI; therefore, their efficacy is unknown. We report two cases of severe bronchial asthma requiring systemic steroid administration while using anti-programmed death-ligand 1 (PD-L1) antibody for advanced non-small-cell lung cancer. The anti-interleukin-5 antibody, mepolizumab, was introduced, resulting in the discontinuation of systemic prednisolone and good asthma control. These reports suggest that treatment with biologics may be effective in severe cases of poorly controlled bronchial asthma during ICI therapy.

Identification of key genes in allergic rhinitis by bioinformatics analysis

Objective

This study aimed to explore the potential molecular mechanism of allergic rhinitis (AR) and identify gene signatures by analyzing microarray data using bioinformatics methods.

Methods

The dataset GSE19187 was used to screen differentially expressed genes (DEGs) between samples from patients with AR and healthy controls. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were applied for the DEGs. Subsequently, a protein–protein interaction (PPI) network was constructed to identify hub genes. GSE44037 and GSE43523 datasets were screened to validate critical genes.

Results

A total of 156 DEGs were identified. GO analysis verified that the DEGs were enriched in antigen processing and presentation, the immune response, and antigen binding. KEGG analysis demonstrated that the DEGs were enriched in Staphylococcus aureus infection, rheumatoid arthritis, and allograft rejection. PPI network and module analysis predicted seven hub genes, of which six (CD44, HLA-DPA1, HLA-DRB1, HLA-DRB5, MUC5B, and CD274) were identified in the validation dataset.

Conclusions

Our findings suggest that hub genes play important roles in the development of AR.

Immunosuppressive Mechanisms of Regulatory B Cells

Regulatory B cells (Bregs) is a term that encompasses all B cells that act to suppress immune responses. Bregs contribute to the maintenance of tolerance, limiting ongoing immune responses and reestablishing immune homeostasis. The important role of Bregs in restraining the pathology associated with exacerbated inflammatory responses in autoimmunity and graft rejection has been consistently demonstrated, while more recent studies have suggested a role for this population in other immune-related conditions, such as infections, allergy, cancer, and chronic metabolic diseases. Initial studies identified IL-10 as the hallmark of Breg function; nevertheless, the past decade has seen the discovery of other molecules utilized by human and murine B cells to regulate immune responses. This new arsenal includes other anti-inflammatory cytokines such IL-35 and TGF-β, as well as cell surface proteins like CD1d and PD-L1. In this review, we examine the main suppressive mechanisms employed by these novel Breg populations. We also discuss recent evidence that helps to unravel previously unknown aspects of the phenotype, development, activation, and function of IL-10-producing Bregs, incorporating an overview on those questions that remain obscure.

Toll-Like Receptor Agonists as Adjuvants for Allergen Immunotherapy

Toll-like receptors (TLRs) are essential components of innate immunity and provide defensive inflammatory responses to invading pathogens. Located within the plasma membranes of cells and also intracellular endosomes, TLRs can detect a range of pathogen associated molecular patterns from bacteria, viruses and fungi. TLR activation on dendritic cells can propagate to an adaptive immune response, making them attractive targets for the development of both prophylactic and therapeutic vaccines. In contrast to conventional adjuvants such as aluminium salts, TLR agonists have a clear immunomodulatory profile that favours anti-allergic T lymphocyte responses. Consequently, the potential use of TLRs as adjuvants in Allergen Immunotherapy (AIT) for allergic rhinitis and asthma remains of great interest. Allergic Rhinitis is a Th2-driven, IgE-mediated disease that occurs in atopic individuals in response to exposure to otherwise harmless aeroallergens such as pollens, house dust mite and animal dander. AIT is indicated in subjects with allergic rhinitis whose symptoms are inadequately controlled by antihistamines and nasal corticosteroids. Unlike anti-allergic drugs, AIT is disease-modifying and may induce long-term disease remission through mechanisms involving upregulation of IgG and IgG4 antibodies, induction of regulatory T and B cells, and immune deviation in favour of Th1 responses that are maintained after treatment discontinuation. This process takes up to three years however, highlighting an unmet need for a more efficacious therapy with faster onset. Agonists targeting different TLRs to treat allergy are at different stages of development. Synthetic TLR4, and TLR9 agonists have progressed to clinical trials, while TLR2, TLR5 and TLR7 agonists been shown to have potent anti-allergic effects in human in vitro experiments and in vivo in animal studies. The anti-allergic properties of TLRs are broadly characterised by a combination of enhanced Th1 deviation, regulatory responses, and induction of blocking antibodies. While promising, a durable effect in larger clinical trials is yet to be observed and further long-term studies and comparative trials with conventional AIT are required before TLR adjuvants can be considered for inclusion in AIT. Here we critically evaluate experimental and clinical studies investigating TLRs and discuss their potential role in the future of AIT.

Regulatory B Cells and Its Role in Central Nervous System Inflammatory Demyelinating Diseases

Regulatory B (Breg) cells represent a population of suppressor B cells that participate in immunomodulatory processes and inhibition of excessive inflammation. The regulatory function of Breg cells have been demonstrated in mice and human with inflammatory diseases, cancer, after transplantation, and particularly in autoinflammatory disorders. In order to suppress inflammation, Breg cells produce anti-inflammatory mediators, induce death ligand-mediated apoptosis, and regulate many kinds of immune cells such as suppressing the proliferation and differentiation of effector T cell and increasing the number of regulatory T cells. Central nervous system Inflammatory demyelinating diseases (CNS IDDs) are a heterogeneous group of disorders, which occur against the background of an acute or chronic inflammatory process. With the advent of monoclonal antibodies directed against B cells, breakthroughs have been made in the treatment of CNS IDDs. Therefore, the number and function of B cells in IDDs have attracted attention. Meanwhile, increasing number of studies have confirmed that Breg cells play a role in alleviating autoimmune diseases, and treatment with Breg cells has also been proposed as a new therapeutic direction. In this review, we focus on the understanding of the development and function of Breg cells and on the diversification of Breg cells in CNS IDDs.

The relationship between B7 homologous 1 with interleukin-4, interleukin-17 and interferon gamma in patients with allergic rhinitis

Background: The etiology of allergic rhinitis includes an increase in cytokine levels, including IL- 4, IL-13, IL-17, and reduction in B7 homologous 1 (B7-H1) or programmed cell death-1 ligand-1 (PD-L1), a new member of the CD28: B7 stimulant molecule family. The aim of this study was to determine the relationship between cytokines and PD-L1. Methods: In this experimental study, 80 patients with allergic rhinitis were enrolled according to inclusion and exclusion criteria. The severity and stage of the disease were determined by a specialist physician. A 5 cc venous blood sample was collected from the patients. IL-4, IL-17, INFγ and PD-L1 were measured using ELISA technique. Results: There was a significant correlation between SPD-L1 and INFγ, IL-4 and IL-17 in allergic rhinitis patients (P < 0.05). Statistical analysis based on the severity of the disease (Mild, Moderate and Severe) showed a significant positive correlation between the SPD-L1 and INFγ in all three levels (P < 0.001). There was also a significant negative correlation between SPD-L1 and two cytokines IL-4 and IL-17 (P < 0.001). Conclusion: PD-L1 may have a protective role against allergic rhinitis, although the precise mechanism requires further detailed studies.

Targeting the tumor microenvironment to overcome immune checkpoint blockade therapy resistance

The ability of immune checkpoint inhibitors (ICIs) to reactivate the killing function of the immune system to tumor cells has led to long lasting immune response presenting highly promising clinical advances. Recently, immune checkpoint inhibitors related resistance due to the specialized tumor microenvironment has also drawn a widely attention. To overcome resistance to immune checkpoint blockade therapy, understanding the relationship of this type of therapy and tumor microenvironment is necessary and critical. This review will focus on how the tumor environment influences the effectiveness of the immunotherapeutic check inhibitors. Finally, we provide a briefly succinct glimpse into the most exciting pre-clinical discoveries and ongoing clinical trials to overcome the resistance of ICIs.

PD-L1+ Regulatory B Cells Are Significantly Decreased in Rheumatoid Arthritis Patients and Increase After Successful Treatment

Background: B cells play an important role in the development and maintenance of rheumatoid arthritis (RA). Although IL-10-producing B cells represent a major subset of regulatory B cells (Bregs) able to suppress autoimmune and inflammatory responses, recent reports showed that B cell-mediated immune suppression may also occur independent of IL-10. For instance, B cells can modulate T cell immune responses through the expression of regulatory molecules such as PD-L1. So far, PD-L1-expressing B cells have not been analyzed in RA patients. Objective: To analyze the frequency of PD-L1-expressing B cells in the peripheral blood of RA patients compared to healthy controls (HC) matched for sex and age, their function on T cell response and their changes in response to therapy. Methods: Fresh peripheral blood B cells from RA patients and HC were characterized by flow cytometry and their functionality assessed in a co-culture system with autologous T cells. Results: The frequencies of CD19⁺PD-L1⁺ B cells, CD24^hiCD38^-PD-L1⁺ and CD24^hiCD38^hiPD-L1⁺ B cells were significantly lower in untreated RA patients than in HC. In a follow-up study, the frequencies of PD-L1⁺ B cells (CD19⁺PD-L1⁺ B cells, CD24^hiCD38^-PD-L1⁺ and CD24^hiCD38^hiPD-L1⁺ B cells) increased significantly after treatment in good responder patients, although the frequency of total CD24^hiCD38^hi B cells decreased. CD19⁺ B cells from untreated RA patients and HC upregulated PD-L1 expression similarly upon stimulation with CpG plus IL-2 and were able to suppress, in vitro, CD8⁺ T cell proliferation and cytokine production in a PD-L1-dependent manner. Conclusions: Our results show that PD-L1⁺ B cells exhibiting T cell suppressive capacity are significantly decreased in untreated RA patients but increase in response to successful treatment. PD-L1 expression on B cells from RA patients can be modulated in vitro and PD-L1⁺ B cells could thus provide new perspectives for future treatment strategies.

Competing endogenous RNA network analysis of CD274, IL‑10 and FOXP3 co‑expression in laryngeal squamous cell carcinoma

Laryngeal squamous cell carcinoma (LSCC) is one of the most common types of head and neck malignant tumor; however, there is a lack of effective molecular targets for therapy. The present study detected the expression of three immunity‑associated molecules [forkhead box (FOX)3, interleukin (IL)‑10 and cluster of differentiation (CD)274] in 133 LSCC samples using immunohistochemistry (IHC); subsequently, the association between their expression and the clinical characteristics of LSCC were analyzed. Spearman's rank correlation method, Kaplan‑Meier and Cox regression model were used to analyze the correlations of the three proteins and their clinical significance. StarBase and miRTarBase databases were used to establish the competitive endogenous (ce)RNA network of the three molecules. IHC demonstrated that the positive expression rates of FOXP3, IL‑10 and CD274 were 68.4, 73.7 and 58.6% in 133 LSCC samples, respectively. In addition, it was identified that the expression of the three proteins was closely correlated with the clinical characteristics of LSCC, including lymph node metastasis and prognosis (P<0.05). There was also a significant association of co‑expression between any two proteins (P<0.001). Furthermore, the expression levels of FOXP3, IL‑10 and CD274 were negatively associated with the survival rate of patients with LSCC (P<0.05). The results of a Cox regression model suggested that the three proteins were prognostic risk factors for LSCC (P<0.05). The ceRNA network revealed that 10 microRNAs (miRs; including miR‑16‑5p and miR‑214‑3p), 123 long non‑coding RNAs (including X‑inactive specific transcript, H19 and metastasis associated lung adenocarcinoma transcript 1) and 408 circular RNAs (including ATP‑binding cassette subfamily C member 1 hsa_circ_001569 and ISY1 splicing factor homolog hsa_circ_001859) may regulate the expression of FOXP3, IL‑10 and CD274. The data generated from the present study may increase the understanding of the immune escape mechanisms of LSCC and may be beneficial for the development of a specific immunotherapy.

Soluble CD80 Protein Delays Tumor Growth and Promotes Tumor-Infiltrating Lymphocytes

Tumor cells use various immune-suppressive strategies to overcome antitumor immunity. One such method is tumor expression of programmed death ligand-1 (PD-L1), which triggers apoptotic death or anergy upon binding programmed death-1 (PD-1) on T cells. Our previous in vitro cellular studies with human and mouse PD-L1⁺ tumor cells demonstrated that a soluble form of the costimulatory molecule CD80 prevented PD-L1-mediated immune suppression and restored T-cell activation by binding PD-L1 and blocking interaction with PD-1. We now report that in vivo treatment of established syngeneic PD-L1⁺ CT26 colon carcinoma and B16F10 melanoma tumors with CD80-Fc delays tumor growth and promotes tumor-infiltrating T cells. Studies with PD-1^-/- and CD28^-/- mice demonstrate that soluble CD80 acts in vivo by simultaneously neutralizing PD-1 suppression and activating through CD28. We also report that soluble CD80 mediates its effects by activating transcription factors EGR1-4, NF-κB, and MAPK, downstream signaling components of the CD28 and T-cell receptor pathways. Soluble CD80 binds to CTLA-4 on activated human peripheral blood mononuclear cells. However, increasing quantities of CTLA-4 antagonist antibodies do not increase T-cell activation. These results indicate that soluble CD80 does not suppress T-cell function through CTLA-4 and suggest that CTLA-4 acts as a decoy receptor for CD80, rather than functioning as a suppressive signaling receptor. Collectively, these studies demonstrate that soluble CD80 has therapeutic efficacy in vivo in mouse tumor systems and that its effects are due to its ability to inhibit PD-1-mediated suppression while concurrently activating T cells through CD28. Cancer Immunol Res; 6(1); 59-68. ©2017 AACR.

Inverse correlation of soluble programmed cell death-1 ligand-1 (sPD-L1) with eosinophil count and clinical severity in allergic rhinitis patients

BACKGROUND

T-cell response outcome is determined by co-stimulatory/inhibitory signals. Programmed cell death-1 ligand-1 (PD-L1) is a member of these co-signaling molecules with known soluble form in human serum. Soluble PD-L1 (sPD-L1) is also recognized in patients with some types of malignancy or autoimmune disorders, though there are few studies on sPD-L1 roles in allergic diseases. The purpose of this survey was to evaluate the association between sPD-L1 levels with eosinophil count as well as disease severity in allergic rhinitis (AR) patients.

METHODS

90 patients with AR were selected. Disease severity was determined by a modified Allergic Rhinitis and its Impact on Asthma (ARIA) classification as mild, moderate and severe. Whole blood samples were collected. Then eosinophil count and serum sPD-L1 were detected by a hematologic analyzer and a commercial ELISA kit.

RESULTS

13 (14.44%), 31 (34.44%), and 46 (51.12%) of patients had mild, moderate and severe disease, respectively. The mean levels of sPD-L1 and eosinophil count were ascertained 18.38 ± 14.42 ng/ml and 422.43 ± 262.26 cell/μl. A significant inverse correlation was determined between sPD-L1 levels and eosinophil count (r = -0.364, P < 0.001). Moreover, we detected a significant negative association between sPD-L1 levels and disease severity (r = -0.384, P < 0.001).

CONCLUSIONS

It is deduced that sPD-L1 can be used as a helpful marker to determine the severity of AR. Furthermore, this study indicated that sPD-L1 may have an inhibitory role in AR development, and its modulation may be considered as a useful accessory therapeutic approach for reduction of AR progression.

Impairment of B-cell functions during HIV-1 infection

A variety of B-cell dysfunctions are manifested during HIV-1 infection, as reported early during the HIV-1 epidemic. It is not unusual that the pathogenic mechanisms presented to elucidate impairment of B-cell responses during HIV-1 infection focus on the impact of reduced T-cell numbers and functions, and lack of germinal center formation in lymphoid tissues. To our understanding, however, perturbation of B-cell phenotype and function during HIV-1 infection may begin at several different B-cell developmental stages. These impairments can be mediated by intrinsic B-cell defects as well as by the lack of proper T-cell help. In this review, we will highlight some of the pathways and molecular interactions leading to B-cell impairment prior to germinal center formation and B-cell activation mediated through the B-cell receptor in response to HIV-1 antigens. Recent studies indicate a regulatory role for B cells on T-cell biology and immune responses. We will discuss some of these novel findings and how these regulatory mechanisms could potentially be affected by the intrinsic defects of B cells taking place during HIV-1 infection.