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Biology subjects

Kunning, S.

Publications and source records attributed to Kunning, S..

3 recordsLinked to original sources

Immunocompetent murine model of Ewing sarcoma reveals role for TGFβ inhibition to enhance immune infiltrates in Ewing tumors during radiation

Ewing sarcoma (ES) is an aggressive cancer diagnosed in adolescents and young adults. The fusion oncoprotein (EWSR1::FLI1) that drives Ewing sarcoma is known to downregulate TGFBR2 expression (part of the TGF{beta} receptor). Because TGFBR2 is downregulated, it was thought that TGF{beta} likely plays an inconsequential role in Ewing biology. However, the expression of TGF{beta} in the Ewing tumor immune microenvironment (TIME) and functional impact of TGF{beta} in the TIME remains largely unknown given the historical lack of immunocompetent preclinical models. Here, we use single-cell RNAseq analysis of human Ewing tumors to show that immune cells, such as NK cells, are the largest source of TGF{beta} production in human Ewing tumors. We develop a humanized (immunocompetent) mouse model of ES and demonstrate distinct TME signatures and metastatic potential in these models as compared to tumors developed in immunodeficient mice. Using this humanized model, we study the effect of TGF{beta} inhibition on the Ewing TME during radiation therapy, a treatment that both enhances TGF{beta} activation and is used to treat aggressive ES. Utilizing a trivalent ligand TGF{beta} TRAP to inhibit TGF{beta}, we demonstrate that in combination with radiation, TGF{beta} inhibition both increases ES immune cell infiltration and decreases lung metastatic burden in vivo. The culmination of these data demonstrates the value of humanized models to address immunobiologic preclinical questions in Ewing sarcoma and suggests TGF{beta} inhibition as a promising intervention during radiation therapy to promote metastatic tumor control.

cancer biology↗

Bifurcated monocyte states are predictive of mortality in severe COVID-19

Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 infection presents with varied clinical manifestations1, ranging from mild symptoms to acute respiratory distress syndrome (ARDS) with high mortality2,3. Despite extensive analyses, there remains an urgent need to delineate immune cell states that contribute to mortality in severe COVID-19. We performed high-dimensional cellular and molecular profiling of blood and respiratory samples from critically ill COVID-19 patients to define immune cell genomic states that are predictive of outcome in severe COVID-19 disease. Critically ill patients admitted to the intensive care unit (ICU) manifested increased frequencies of inflammatory monocytes and plasmablasts that were also associated with ARDS not due to COVID-19. Single-cell RNAseq (scRNAseq)-based deconvolution of genomic states of peripheral immune cells revealed distinct gene modules that were associated with COVID-19 outcome. Notably, monocytes exhibited bifurcated genomic states, with expression of a cytokine gene module exemplified by CCL4 (MIP-1{beta}) associated with survival and an interferon signaling module associated with death. These gene modules were correlated with higher levels of MIP-1{beta} and CXCL10 levels in plasma, respectively. Monocytes expressing genes reflective of these divergent modules were also detectable in endotracheal aspirates. Machine learning algorithms identified the distinctive monocyte modules as part of a multivariate peripheral immune system state that was predictive of COVID-19 mortality. Follow-up analysis of the monocyte modules on ICU day 5 was consistent with bifurcated states that correlated with distinct inflammatory cytokines. Our data suggests a pivotal role for monocytes and their specific inflammatory genomic states in contributing to mortality in life-threatening COVID-19 disease and may facilitate discovery of new diagnostics and therapeutics.

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↗