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Biology subjects

Kupper, T. S.

Publications and source records attributed to Kupper, T. S..

4 recordsLinked to original sources

Regulatory T cells inhibit CD8+ TRM-like cells during the early stages of tumor immune escape

How the immune system surveys nascent tumors and how this surveillance is subverted remain poorly understood. Using high-plex cyclic immunofluorescence and 3D imaging, we identified regulatory T (Treg) cells that co-localize with tissue-resident memory (TRM)-like T cells in early-stage human melanoma. In an autochthonous Braf/PTEN melanoma model expressing a defined tumor antigen, the initial CD8+ T cell infiltrate adopts a CD103+CD101+ TRM-like fate, establishing active immunosurveillance within nascent lesions. TRM-like cells dominate early tumors, occupy a stable epidermal niche, express effector molecules, and initiate T cell recruitment. However, Treg cells adopt a parallel tissue-resident phenotype, co-localizing with TRM-like cells and restraining both cytotoxic and sentinel functions. Tumor-site-specific Treg depletion reactivated TRM-like cells, drove robust T cell recruitment, expanded tumor-specific responses, and limited tumor growth. These findings reveal how early immunosurveillance is established through tissue-resident programs and identify Treg co-option of this response as a critical mechanism of tumor immune evasion. One Sentence SummaryNascent melanoma imprints a tissue-resident program on the initial CD8+ T cell infiltrate, which is suppressed by regulatory T cells as a critical checkpoint in immune evasion.

immunology↗

Human skin rejuvenation via mRNA

Aging is characterized by a gradual decline in function, partly due to accumulated molecular damage. Human skin undergoes both chronological aging and environmental degradation, particularly UV-induced photoaging. Detrimental structural and physiological changes caused by aging include epidermal thinning due to stem cell depletion and dermal atrophy associated with decreased collagen production. Here, we present a comprehensive single-cell atlas of skin aging, analyzing samples from young, middle-aged, and elderly individuals, including both sun-exposed and sun-protected areas. This atlas reveals age-related changes in cellular composition and function across various skin cell types, including epidermal stem cells, fibroblasts, hair follicles, and endothelial cells. Using our atlas, we have uncovered basal stem cells as a highly variable population across aging, more so than other skin cell populations, such as fibroblasts. In basal stem cells, we identified ATF3 as a novel regulator of skin aging. ATF3 is a transcriptional factor for genes involved in the aging process, with its expression reduced by 20% during aging. Based on this discovery, we developed an innovative mRNA-based treatment to mitigate the effects of skin aging. After treatment with ATF3 mRNA, cell senescence decreased 25%, and we observed an over 20% increase in proliferation in treated basal stem cells. Importantly, we also found communication between keratinocytes and fibroblasts as a critical component of therapeutic interventions, with ATF3 mRNA rescue of basal cells significantly enhancing fibroblast collagen production by approximately 200%. Furthermore, we validated the efficacy of ATF3 mRNA treatment in ex vivo human skin and in vivo mouse models. In ex vivo human skin, microneedle-mediated delivery of ATF3 mRNA induced robust rejuvenation, expanding the basal stem-cell population and enhancing dermal ECM reconstruction. In a wound healing mouse model, ATF3 mRNA reduced scarring, demonstrating strong regenerative potential for reversing age-related skin decline. We conclude that ATF3 mRNA treatment effectively reverses the effects of skin aging by modulating specific cellular mechanisms, offering a novel, targeted approach to human skin rejuvenation.

synthetic biology↗

Resident memory T cell development is associated with AP-1 transcription factor upregulation across anatomical niches.

Tissue-resident memory T (TRM) cells play a central role in immune responses to pathogens across all barrier tissues after infection. However, the underlying mechanisms that drive TRM differentiation and priming for their recall effector function remains unclear. In this study, we leveraged both newly generated and publicly available single-cell RNA-sequencing (scRNAseq) data generated across 10 developmental time points to define features of CD8 TRM across both skin and small-intestine intraepithelial lymphocytes (siIEL). We employed linear modeling to capture temporally-associated gene programs that increase their expression levels in T cell subsets transitioning from an effector to a memory T cell state. In addition to capturing tissue-specific gene programs, we defined a consensus TRM signature of 60 genes across skin and siIEL that can effectively distinguish TRM from circulating T cell populations, providing a more specific TRM signature than what was previously generated by comparing bulk TRM to naive or non-tissue resident memory populations. This updated TRM signature included the AP-1 transcription factor family members Fos, Fosb and Fosl2. Moreover, ATACseq analysis detected an enrichment of AP-1-specific motifs at open chromatin sites in mature TRM. CyCIF tissue imaging detected nuclear co-localization of AP-1 members Fosb and Junb in resting CD8 TRM >100 days post-infection. Taken together, these results reveal a critical role of AP-1 transcription factor members in TRM biology and suggests a novel mechanism for rapid reactivation of resting TRM in tissue upon antigen encounter.

immunology↗

Skin Delivery of Modified Vaccinia Ankara Viral Vectors Generates Superior T Cell Immunity Against a Respiratory Viral Challenge

Modified Vaccinia Ankara (MVA) was recently approved as a Smallpox vaccine. Transmission of Variola is by respiratory droplets, and MVA delivered by skin scarification (s.s.) protected mice far more effectively against lethal respiratory challenge with VACV than any other route of delivery, and at much lower doses. Comparisons of s.s. with intradermal, subcutaneous or intramuscular routes showed that MVAOVA s.s.-generated T cells were both more abundant and transcriptionally distinct. MVAOVA s.s. produced greater numbers of lung Ova-specific CD8+ TRM and was superior in protecting mice against lethal VACVOVA respiratory challenge. Nearly as many lung TRM were generated with MVAOVA s.s. compared to direct pulmonary immunization with MVAOVA, and both routes vaccination protected mice against lethal pulmonary challenge with VACVOVA. Strikingly, MVAOVA s.s.-generated effector T cells exhibited overlapping gene transcriptional profiles to those generated via direct pulmonary immunization. Overall, our data suggest that heterologous MVA vectors delivered via s.s. are uniquely well-suited as vaccine vectors for respiratory pathogens like COVID-19. In addition, MVA delivered via s.s. could represent a more effective dose-sparing smallpox vaccine.

immunology↗