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Skvir, N. J.

Publications and source records attributed to Skvir, N. J..

2 recordsLinked to original sources

IPSC-based modeling of resiliency in centenarians reveals longevity-specific signatures

Centenarians represent a human model of resilience to age-related decline, yet resiliency mechanisms remain elusive. Here, we establish an induced pluripotent stem cell (iPSC)-based platform to interrogate resilience signatures in centenarians. IPSC-derived neurons from centenarians exhibit transcriptional programs promoting synaptic integrity, calcium homeostasis, and cholesterol biosynthesis, while suppressing proteostatic stress pathways. Functionally, these neurons maintain stable calcium dynamics, reduced baseline mitochondrial activity, and energy-efficient homeostasis. Upon challenge, centenarian-derived neurons mount a robust stress response, in contrast to attenuated responses in non-centenarian controls. This resilience signature parallels adaptations in long-lived mammals and aligns with healthy brain aging, while showing erosion in Alzheimers disease and cancer. Our platform provides a scalable human model for dissecting resilience biology offering a framework to extend healthspan and mitigate age-related decline.

molecular biology↗

High resolution spatial profiling of the hematopoietic landscape of the murine lung

Our current understanding of blood cell development and functionality stems primarily from the investigation of adult bone marrow (BM) and the fetal liver prenatally. However, emerging evidence highlights the lung as a previously underappreciated residence for hematopoietic cells. While a diversity of cells specific to the BM are known to promote the maturation and trafficking of hematopoietic cells, how the lung niche influences the development and functionality of resident cells is not known. Spatial in situ transcriptomics enables accurate mapping of cell identities and interactions within intact tissue, providing insights not accessible by dissociated single-cell profiling. Here, we present a high-resolution spatial transcriptomic atlas of the healthy adult murine lung placing specific emphasis on the hemato-endothelial landscape of this organ. As a case study, we developed a semi-automatic workflow to explicitly identify and curate rare - often multinucleated - megakaryocytes, requiring a combination of hex-binning spatial enrichment of canonical markers, expert curation, and cell boundary merging to correct for segmentation artifacts. We then characterized the spatial neighborhoods of megakaryocytes, illustrating their topological embedding within vascular, stromal, and immune microenvironments. Finally, we demonstrated the utility of this dataset for hypothesis-driven signaling studies by examining ligand-receptor interactions across pathways including BMP, VEGF, and ECM-integrin signaling. Together, this work defines the lung-blood niche and advances our understanding of the organ-specific properties of blood cells. We also provide a high-resolution spatial reference for the murine lung and demonstrate how targeted spatial in situ transcriptomics enable focused case studies of rare hematopoietic niches. KEY POINTSO_LIThis work represents the highest resolution gene expression mapping of the spatial symbiosis between the hematopoietic and pulmonary systems. C_LIO_LIPulmonary megakaryocytes localize within distinct vascular and stromal neighborhoods. C_LI

cell biology↗