Expansion of CD4+ cytotoxic T lymphocytes with specific gene expression patterns may contribute to suppression of tumor immunity in oral squamous cell carcinoma: single-cell analysis and in vitro experiments

Background

Cancer immunotherapy targeting CD8+ T cells has made remarkable progress, even for oral squamous cell carcinoma (OSCC), a heterogeneous epithelial tumor without a substantial increase in the overall survival rate over the past decade. However, the therapeutic effects remain limited due to therapy resistance. Thus, a more comprehensive understanding of the roles of CD4+ T cells and B cells is crucial for more robust development of cancer immunotherapy.

Methods

In this study, we examined immune responses and effector functions of CD4+ T cells, CD8+ T cells and B cells infiltrating in OSCC lesions using single-cell RNA sequencing analysis, T cell receptor (TCR) and B cell receptor (BCR) repertoire sequencing analysis, and multi-color immunofluorescence staining. Finally, two Kaplan-Meier curves and several Cox proportional hazards models were constructed for the survival analysis.

Results

We observed expansion of CD4+ cytotoxic T lymphocytes (CTLs) expressing granzymes, which are reported to induce cell apoptosis, with a unique gene expression patterns. CD4+ CTLs also expressed CXCL13, which is a B cell chemoattractant. Cell-cell communication analysis and multi-color immunofluorescence staining demonstrated potential interactions between CD4+ CTLs and B cells, particularly IgD- CD27- double negative (DN) B cells. Expansion of CD4+ CTLs, DN B cells, and their contacts has been reported in T and B cell-activated diseases, including IgG4-related disease and COVID-19. Notably, we observed upregulation of several inhibitory receptor genes including CTLA-4 in CD4+ CTLs, which possibly dampened T and B cell activity. We next demonstrated comprehensive delineation of the potential for CD8+ T cell differentiation towards dysfunctional states. Furthermore, prognostic analysis revealed unfavorable outcomes of patients with a high proportion of CD4+ CTLs in OSCC lesions.

Conclusion

Our study provides a dynamic landscape of lymphocytes and demonstrates a systemic investigation of CD4+ CTL effects infiltrating into OSCC lesions, which may share some pathogenesis reported in severe T and B cell-activated diseases such as autoimmune and infectious diseases.

"Age could not wither her…" because of her cytotoxic CD4+ T cells?

Cytotoxic CD4⁺ T cells specific for CMV cull senescent skin fibroblasts.

Idiopathic pulmonary fibrosis diagnosed concomitantly with diffuse squamous cell lung cancer on surgical lung biopsy: a case report

Background

Idiopathic pulmonary fibrosis is a disease with a poor prognosis and has been associated with increased lung cancer incidence.

Case presentation

We report the case of a Caucasian 75-year-old woman, a former smoker, hospitalized for breathlessness with a chest computed tomography scan showing an interstitial lung disease. A surgical lung biopsy was performed, confirming a pattern of usual interstitial pneumonia but also numerous disseminated foci of well-differentiated focally invasive squamous cell carcinoma without hypermetabolic lung nodule, mass, or enlarged lymph node visualized on chest computed tomography or positron emission tomography scan. Nintedanib was started for its antifibrotic and antitumor properties, without any other antineoplastic treatment. Three years after initiation of nintedanib, clinical, functional, and computed tomography scan evaluations were stable, and there was no evidence for evolution of the squamous cell carcinoma.

Conclusions

Data are scarce regarding the benefit of nintedanib in patients with idiopathic pulmonary fibrosis-associated lung cancer, and it is unclear whether nintedanib could have a preventive role in lung carcinogenesis in idiopathic pulmonary fibrosis patients. This experience could help the scientific community in case of similar incidental findings.

Incidence of allergic rhinitis in children with residual snoring and sleep symptoms after adenotonsillectomy

BACKGROUND AND OBJECTIVES

Allergic rhinitis may contribute to sleep disordered breathing (SDB) in children. Although adenotonsillectomy is commonly performed to treat SDB, some patients will return to their primary practitioners with residual sleep symptoms. The aim of this study was to assess the incidence of allergic rhinitis via radioallergosorbent testing (RAST) in children undergoing adenotonsillectomy who had residual snoring or sleep symptoms.

METHOD

A retrospective analysis of 500 patients post-adenotonsillectomy was undertaken. The incidence of residual snoring, residual sleep symptoms and results of RAST, as well as total immunoglobulin E (IgE) after surgical intervention, were documented.

RESULTS

Children with positive RAST results or elevated total IgE had a significantly greater incidence of residual snoring post-adenotonsillectomy (P = 0.049) and residual sleep symptoms after surgery (P <0.0001).

DISCUSSION

A positive RAST or elevated IgE in children with SDB was associated with incomplete resolution of snoring and residual sleep symptoms after adenotonsillectomy. Thus, there should be raised suspicion of allergic rhinitis in this population.

Cutaneous immuno-surveillance and regulation of inflammation by group 2 innate lymphoid cells (P6374)

Type 2 immunity is critical for defense against cutaneous infections, but also underlies the development of allergic skin diseases. We report the identification in normal murine dermis of an abundant, phenotypically unique group 2 innate lymphoid cell (ILC2) subset that depends on IL-7 and constitutively produces IL-13. Intravital multiphoton microscopy revealed that dermal ILC2 specifically interact with mast cells, whose function is suppressed by IL-13. Treatment of Rag1−/− mice with IL-2 led to a marked expansion of activated, IL-5-producing dermal ILC2, resulting in the development of spontaneous dermatitis characterized by eosinophil infiltrate and activated mast cells. Our data uncover a novel interactive pathway between two innate immune cell populations implicated in type 2 immunity, and demonstrate that ILC2 exhibit both pro- and anti-inflammatory properties.