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Biology subjects

Ventre, K. S.

Publications and source records attributed to Ventre, K. S..

3 recordsLinked to original sources

Lymphatic egress recycles tumor-experienced effector CD8 T cells to sustain immune surveillance

Successful anti-tumor immune surveillance depends on stem-like CD8+ T cells that are enriched in tumor-draining lymph nodes (LN), but how they are maintained over time remains poorly understood. Here, we identify a continuous lymphatic circuit that sustains stem-like CD8+ T cells. Using photoconversion to fate-map intratumoral T cells we demonstrate that effector cells exit the tumor microenvironment and migrate back to the draining LN. These tumor-specific, migratory effector T cells avoid chronic antigen stimulation, re-express the transcription factor associated with self-renewal, TCF1, and enter a stem-like state in the LN. Antigen presentation in LNs by dendritic cells drives their proliferation thereby inflating the LN stem-like population. Consequently, maintenance of stem-like T cells and ICB response depends on constitutive lymphatic transport, while LN metastasis compromises the stem-like niche, diminishing ICB response. We, therefore, define a continuous, peripheral lymphatic circuit that recycles tumor-experienced effector T cells to fuel durable, systemic immune surveillance.

immunology↗

NF1 Loss Remodels Tumor Niches for Immune Evasion

Genetic and transcriptional alterations in cancer cells shape their interactions with immune and stromal compartments, influencing tumor progression, immune evasion, and response to immune checkpoint inhibitors (ICI). Yet, how these interactions are organized within tumor architecture and linked to clinical outcomes remains unclear. Neurofibromin 1 (NF1) is a tumor suppressor gene that is frequently inactivated across multiple cancer types. NF1 loss-of-function mutations occur in up to 27% of melanoma cases and are associated with poor clinical outcomes. Here, we used spatial multi-omics analysis to uncover 12 meta-niches, each comprising distinctive cell types with distinct characteristics, in human melanoma tissues. We found that niches containing immunosuppressive cancer-associated fibroblasts (CAFs) and macrophages were significantly enriched in NF1 mutant melanoma (NF1Mut) tissues. In contrast, niches containing cytotoxic CD8 T cells were significantly diminished. NF1 loss correlates with increased epidermal growth factor signaling (EGFR) signaling and reduced antigen presentation in tissues with limited CD8 T cell infiltration in both human and mouse melanoma. We demonstrate that EGFR inhibition restores antigen presentation and activates immune responses in a syngeneic Nf1 knockdown model resistant to ICIs. These data, therefore, define functionally distinctive niches enriched in NF1Mut melanoma that likely contribute to their aggressive nature and nominate EGFR signaling as a specific target to reinvigorate ICI responses. We therefore link an understudied genetic driver to specific immune architectures and ultimately therapy resistance and suggest a therapeutic strategy expected to improve treatment outcomes in NF1Mut melanoma patients.

cancer biology↗

Epigenetic Reprogramming Alters Intestinal Stem Cell Fate in Pouchitis

Intestinal stem cells (ISCs) mediate the continuous renewal of the epithelium during homeostasis and recovery from injury. To investigate the molecular impact of inflammation on human ISCs and the role of janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling, we established an organoid model derived from individuals with pouchitis, a form of inflammatory bowel disease that develops in an organ generated from ileal pouch-anal anastomosis (IPAA) surgery. Compared with non-inflamed specimens, pouchitis organoids exhibited increased apoptosis and secretory lineage differentiation that were stable after multiple passages, mirroring findings in primary pouch tissue. Chromatin accessibility and histone modification profiling of ISCs revealed inflammation-driven epigenetic remodeling, particularly involving activator protein 1 (AP-1) transcription factors such as c-Jun and excessive STAT1 activity. Loss of c-Jun disrupted ISC viability and enhanced secretory cell differentiation in non-inflamed organoids, whereas therapies targeting JAK/STAT reversed these ISC defects and chromatin changes in pouchitis organoids. Together, these results associated inflammation with epigenetic changes in human ISCs, suggesting that immune-mediated injury has lasting effects on the pouch epithelium that can potentially be reversed through JAK/STAT therapies.

cell biology↗