Differential Plasma-cell evolution is linked with Dermatophagoides pteronyssinus immunotherapy response

Sequential class switch recombination to IgE and allergen-induced accumulation of IgE+ plasmablasts occur in the nasal mucosa of local allergic rhinitis patients

BACKGROUND

The involvement of allergen-specific (s)IgE in local allergic rhinitis (LAR) has been debated. Here, we investigate the effect of nasal allergen challenge with Dermatophagoides pteronyssinus (NAC-DP) in mucosal and peripheral B-cell subpopulations in LAR patients.

METHODS

Nine LAR, 5 allergic rhinitis (AR), and 5 non-atopic healthy control (HC) individuals were subjected to a 3-day NAC-DP protocol, and nasal biopsies and blood samples were collected before and after provocation. Nasal biopsies were used for immunohistochemistry and gene expression studies, whereas the frequency of lymphocyte subsets and basophil activation test (BAT) were analyzed in blood samples by flow cytometry. sIgG was measured in sera.

RESULTS

NAC-DP induced an increase in IgE⁺ CD38⁺ plasmablasts in the nasal mucosa of LAR patients, but not in AR or HC individuals. Markers of sequential recombination to IgE (εCSR) (from IgG) were observed in 33% of LAR, 20% of AR, and 0% of HC subjects. NAC-DP increased the proportion of peripheral CD19⁺ CD20⁺ CD38⁺ plasmablasts in AR and LAR patients, but not in HC. Expression of the mucosal homing receptor CXCR3 in peripheral CD19⁺ CD20⁺ CD38⁺ plasmablasts from LAR, AR, and HC individuals was 7%, 5%, and 0.5%, respectively. In vitro DP stimulation increased proliferating CD19⁺ CD20⁺ CD38⁺ plasmablasts in LAR and AR patients, but not in HC. Serum DP-sIgG was higher in LAR and AR patients as compared to HC. BAT was positive in 33%, 100%, and 0% of LAR, AR, and HC subjects, respectively.

CONCLUSION

These results suggest that allergen exposure induces the sequential εCSR of IgG⁺ CD19⁺ CD20⁺ CD38⁺ plasmablasts in the nasal mucosa of LAR patients.

Prediction of clinical efficacy of subcutaneous immunotherapy for Artemisia sieversiana pollen allergic rhinitis by serum metabolomics

BACKGROUND/PURPOSE

Specific immunotherapy is the only effective etiological treatment for allergic rhinitis, but subcutaneous immunotherapy has a slow onset and poor compliance. Predicting the clinical efficacy of subcutaneous immunotherapy in advance can reduce unnecessary medical costs and resource waste. This study aimed to identify metabolites that could predict the efficacy of subcutaneous immunotherapy on seasonal allergic rhinitis by serum metabolomics.

METHODS

Patients (n = 43) with Artemisia sieversiana pollen allergic rhinitis were enrolled and treated with subcutaneous immunotherapy for one year. Patients were divided into the ineffective group (n = 10) and effective group (n = 33) according to the therapeutic index. Serum samples were collected before treatment. Metabolomics was determined by liquid chromatography-mass spectrometry combined with gas chromatography-mass spectrometry and analyzed differential compounds and related metabolic pathways.

RESULTS

A total of 129 differential metabolites (P < 0.05) were identified and 4 metabolic pathways, namely taurine and hypotaurine metabolism, pentose and glucuronate interconversions, pentose phosphate pathway, and alanine, aspartate, and glutamate metabolism, were involved.

CONCLUSION

Some metabolites, such as hypotaurine, taurine, and l-alanine, have the potential to become predictive biomarkers for effective subcutaneous immunotherapy.

The CD4+CD25+FoxP3+ Regulatory T Cells Regulated by MSCs Suppress Plasma Cells in a Mouse Model of Allergic Rhinitis

Background:

Allergic Rhinitis (AR) is the most common immunological disease that has been associated with inflammatory responses and is characterized by sneezing. Previous studies found that AR's allergen exposure significantly induces plasma cells and reduces regulatory T (Treg) cells, a population that contributes to control AR. Therefore, upregulating Treg expression can regulate plasma cells leading to inhibit sneezing in AR. Mesenchymal stem cells (MSCs) are multipotent stem cells that have the immunoregulatory and antiinflammation ability by secreting various cytokines including IL-10 and TGF-β which potent as a promising therapeutic modality for allergic airway diseases, including AR.

Objective:

To investigate the role of MSCs in generating CD4+, CD25+, and Foxp3+ Regulatory T cells associated with suppressing plasma cell in AR model.

Methods:

In this study, fifteen male Wistar rats (6 to 8 weeks old) were randomly divided into three groups (control group, sham group, and MSCs treatment group). OVA nasal challenge was conducted daily from day 15 to 21, and MSCs (1x10⁶) were administrated intraperitoneally to OVA-sensitized rats on day 21. Sneezing was observed from day 22 to 28. The rats were sacrificed on day 22 and day 28. The expression of CD4+ CD25+ Foxp3+ in Treg and plasma cells was analyzed by flow cytometry assay.

Results:

This study showed that the percentage of plasma cell and sneezing times significantly decreased in MSCs treatment. This finding was aligned with the significant increase of CD4+CD25+Foxp3+ Treg level.

Conclusion:

MSCs administration suppress plasma cells population and sneezing times by up regulating Treg to control AR.

Analysis of tumor mutation burden combined with immune infiltrates in endometrial cancer

BACKGROUND

Tumor mutational burden (TMB) is widely regarded as a predictor of response to immunotherapy. Few researchers have focused on the activity and prognosis of TMB in endometrial cancer (EC) and immune cells. Our study aimed to identify the prognostic role of TMB in EC.

METHODS

We downloaded transcriptome data from The Cancer Genome Atlas (TCGA) database. Kaplan-Meier analysis with log-rank test was conducted to assess the difference in overall survival (OS) between the high and low TMB groups. The "CIBERSORT" scripts were performed to evaluate the immune compositions of EC patients. Cox regression analysis and survival analysis were used to verify the prognostic value prognosis of TMB.

RESULTS

We obtained the single nucleotide mutation data for 529 EC patients. A missense mutation was the most common mutation type. TMB was associated with survival outcome, tumor grades, and pathological types. We identified 10 hub TMB-related signature and found that elevated T-cell subsets infiltrating density in the high TMB group revealed improved survival outcomes. According to Kaplan-Meier analysis, T cells gamma delta and T cells regulatory were prognostic immune cells in EC samples. Moreover, many top gene set enrichment analysis (GSEA) results, including amino sugar and nucleotide sugar metabolism, nucleotide excision repair, or p53 signaling pathway, were enriched significantly with TMB level as phenotype.

CONCLUSIONS

TMB is an important prognostic factor for EC, and TMB-related genes may be potential therapeutic targets for EC.

Leukotriene A4 Hydrolase Is a Candidate Predictive Biomarker for Successful Allergen Immunotherapy

Background

Allergic rhinitis is a common disorder that affects 10% to 40% of the population worldwide. Allergen immunotherapy (AIT) represents the only therapy that has the potential to resolve clinical symptoms of allergic rhinitis. However, up to 30% of patients do not respond to AIT. Biomarkers predicting the clinical efficacy of AIT as early as possible would significantly improve the patient selection and reduce unnecessary societal costs.

Methods

Artemisia pollen allergic patients who received at least 1-year AIT were enrolled. Clinical responses before and after 1-year AIT were evaluated to determine AIT responders. Artemisia specific IgE and IgG4 levels were measured by using ImmunoCAP and enzyme-linked immunosorbent assay (ELISA) separately. Stepwise regression analysis was performed to identify which rhinitis-relevant parameters explained the most variability in AIT results. Liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics was applied to identify the potential candidate biomarkers in the sera of responders and non-responders collected before and after 1-year therapy. The diagnostic performance of the potential biomarkers was then assessed using enzyme-linked immunosorbent assay (ELISA) in 30 responders and 15 non-responders.

Results

Artemisia specific IgE and IgG4 levels were elevated only in the responders. Regression analysis of allergic rhinitis-relevant parameters provided a robust model that included two most significant variables (sneeze and nasal congestion). Thirteen candidate biomarkers were identified for predicting AIT outcomes. Based on their association with allergy and protein fold change (more than 1.1 or less than 0.9), four proteins were identified to be potential biomarkers for predicting effective AIT. However, further ELISA revealed that only leukotriene A₄ hydrolase (LTA₄H) was consistent with the proteomics data. The LTA₄H level in responders increased significantly (P < 0.001) after 1-year therapy, while that of non-responders remained unchanged. Assessment of LTA₄H generated area under curve (AUC) value of 0.844 (95% confidence interval: 0.727 to 0.962; P < 0.05) in distinguishing responders from the non-responders, suggesting that serum LTA₄H might be a potential biomarker for predicting the efficiency of AIT.

Conclusion

Serum LTA₄H may be a potential biomarker for early prediction of an effective AIT.

Immunological Changes Induced in Peach Allergy Patients with Systemic Reactions by Pru p 3 Sublingual Immunotherapy

SCOPE

Sublingual immunotherapy using peach extract enriched in Pru p 3 (Pru p 3-enriched-SLIT) brings a new perspective to treating patients with allergy to lipid transfer proteins. We evaluate the immunological changes induced by Pru p 3-enriched-SLIT during one year.

METHODS AND RESULTS

Three groups are included: peach allergic patients who receive Pru p 3-enriched-SLIT, peach allergic untreated patients, and controls. Peripheral blood mononuclear cells are obtained before treatment and at different time-points. Monocyte-derived dendritic cells (moDCs) maturation and lymphocyte proliferation are assessed by flow cytometry. Data showed a significant reduction of moDCs maturation status during one year of treatment and an increase in PD-L1. Moreover, we observed a significant decrease of the Pru p 3-specific proliferation of effector cells and an increase in regulatory T (Treg) cells with higher PD-L1 expression and IL-10 production. These are observed in patients treated only.

CONCLUSION

Successful Pru p 3-enriched-SLIT is linked to an important immunosuppression of allergen-specific effector T cells, potentially due to an increase of allergen-specific Treg cells. These cellular changes are orchestrated by the activity of moDCs promoting the expression of PD-L1 that will participate in the regulatory response. These changes may serve as biomarkers during SLIT alongside other features such as IgE/IgG₄ ratio.

Dermatophagoides pteronyssinus immunotherapy changes the T-regulatory cell activity

Subcutaneous specific immunotherapy (SCIT) has been shown to modify the Dermatophagoides pteronissinus (DP) allergic response, characterized by generation of Treg cells. However, studies have reported no changes in the proportion of Treg cells after immunotherapy, indicating that the effects may be due to modifications in their regulatory activities. We aimed to determine whether Tregs generated by DP-SCIT can switch the allergic response to tolerant and study the involvement of suppressive cytokines on it. Twenty-four DP-allergic rhinitis patients were recruited, 16 treated with DP-SCIT and 8 untreated. Treg and T effector cells were isolated before and after DP-SCIT, and cocultured in different combinations with α-IL-10, α-TGF-β blocking antibodies and nDer p 1. Treg cells after DP-SCIT increased Th1 and decreased Th2 and Th9 proliferation. Similarly, they increased IL-10 and decreased IL-4 and IL-9-producing cells. α-IL-10 affected the activity of Treg cells obtained after DP-SCIT only. Finally, DP-specific IgG4 levels, Treg percentage and IL-10 production were correlated after DP-SCIT. These results demonstrate that DP-SCIT induces Treg cells with different suppressive activities. These changes could be mediated by IL-10 production and appear to play an important role in the induction of the tolerance response leading to a clinical improvement of symptoms.