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Biology subjects

Ferris, R. L.

Publications and source records attributed to Ferris, R. L..

3 recordsLinked to original sources

Expression of Tim-3 drives naive Treg to an effector-like state with enhanced suppressive activity

Regulatory T cells (Treg) are critical mediators of self-tolerance but can also limit effective anti-tumor immunity. We and others previously reported that 40-60% percent of Treg-infiltrating head and neck cancer (HNC) and other tumors highly express Tim-3, compared with about 5% in lymphoid organs. Tumor-infiltrating Tim-3+ Treg also have enhanced suppressive function and display a more effector-like phenotype. Using a novel mouse model with cell type-specific Tim-3 expression, we show here that expression of Tim-3 by Treg is sufficient to drive Treg to a more effector-like phenotype, resulting in enhanced suppressive activity and increased tumor growth. These findings may help to reconcile previous reports that some Tim-3 antibodies enhance T cell responses in vivo, while expression of Tim-3 has a cell-intrinsic ability to enhance TCR signaling and T cell activation. Thus, we propose that Tim-3 regulates anti-tumor immunity at least in part through enhancement of Treg function. To our knowledge, this is the first example in which expression of a single co-stimulatory molecule is sufficient to drive differentiation of Treg in this manner.

immunology

Divergent cancer etiologies drive distinct B cell signatures and tertiary lymphoid structures

Current immunotherapy paradigms aim to reinvigorate CD8+ T cells, but the contribution of humoral immunity to antitumor immunity remains understudied1,2. Head and neck squamous cell carcinoma (HNSCC) is caused by either human papillomavirus (HPV+) or environmental carcinogens (i.e. tobacco and alcohol; HPV-)3,4. Here, we demonstrate that HPV+ HNSCC patients have transcriptional signatures of germinal center (GC) tumor infiltrating B cells (TIL-Bs) and spatial organization of immune cells consistent with GC-like tertiary lymphoid structures (TLS), both of which correlate with favorable outcomes in HNSCC patients. Further, our single-cell RNAseq data also indicate that GC TIL-Bs are characterized by distinct waves of gene expression consistent with dark zone, light zone and a transitional state of GC B cells. High-dimensional spectral flow cytometry permitted in depth characterization of activated, memory and GC TIL-Bs. Further, single cell RNAseq analysis and subsequent protein validation identified a role for semaphorin 4a (Sema4a) in the differentiation of GC TIL-Bs and indicated that expression of Sema4a was enhanced on GC TIL-Bs and within GC-like TLS in the TME. Thus, in contrast to some reports on the detrimental role of TIL-Bs in human tumors, our findings suggest that TIL-Bs play an instrumental role in antitumor immunity5,6. Novel therapeutics to enhance TIL-B responses in HNSCC should be prioritized as a compliment to current T-cell mediated immunotherapies.

immunology

Systemic immune dysfunction in cancer patients driven by IL6 and IL8 induction of an inhibitory receptor module in peripheral CD8+ T cells

Many cancer patients do not develop a durable response to the current standard of care immunotherapies despite substantial advances in targeting immune inhibitory receptors1-5. A potential compounding issue, which may serve as an unappreciated, dominant resistance mechanism, is an inherent systemic immune dysfunction that is often associated with advanced cancer6-12. Minimal response to inhibitory receptor (IR) blockade therapy and increased disease burden have been associated with peripheral CD8+ T cell dysfunction, characterized by suboptimal T cell proliferation and chronic expression of IRs (eg. Programmed Death 1 [PD1] and Lymphocyte Activation Gene 3 [LAG3])13, 14. Here, we demonstrate that up to a third of cancer patients express robust intracellular LAG3 (LAG3IC), but not surface LAG3 (LAG3SUR), in peripheral CD8+ T cells compared to CD4+ T cells and regulatory T cells (Tregs). LAG3IC is associated with: (i) expression of a LAG3IC-dominant IR module that includes PD1IC, NRP1IC, CD39IC, and TIGITIC; (ii) decreased CD8+ but not CD4+ T cell function that can be reversed by anti-LAG3 (and/or anti-PD1), despite limited constitutive surface IR expression; and (iii) poor disease prognosis. Systemic immune dysfunction is restricted to CD8+ T cells, including a high percentage of peripheral naive CD8+ T cells, indicating a TCR-independent mechanism that is driven by the cytokine IL6 and the chemokine IL8. Thus, the combination of an increased LAG3-dominant IR module and elevated systemic IL6 and/or IL8 may serve as predictive biomarkers and increase the possibility that cancer patients will benefit from therapeutic combinations targeting these systemic cytokines in the setting of PD1 and/or LAG3 blockade.

cancer biology