Transcriptomic analysis of skeletal muscle regeneration across mouse lifespan identifies altered stem cell states.

In aging, skeletal muscle regeneration declines due to alterations in both myogenic and non-myogenic cells and their interactions. This regenerative dysfunction is not understood comprehensively or with high spatiotemporal resolution. We collected an integrated atlas of 273,923 single-cell transcriptomes and high-resolution spatial transcriptomic maps from muscles of young, old and geriatric mice (~5, 20 and 26 months old) at multiple time points following myotoxin injury.

The Positive School Safety Program (PSSP) for School Officers: Implementation Processes and Outcomes.

Approximately 50% of U.S. students attend a school with a school officer.

Cutting Edge: Retinoic Acid Promotes Brain-homing of CD8+ T Cells during Congenital Cytomegalovirus Infection.

The most common congenital viral infection is CMV, which leads to numerous neurologic disabilities. Using a mouse model of congenital CMV, we previously determined that Ag-specific CD8+ T cells traffic to the brain in a CCR9-dependent manner. The mechanism by which these CD8+ T cells acquire a CCR9-dependent "brain-tropic" phenotype remains unclear.

Gene Regulatory Programs that Specify Age-Related Differences during Thymocyte Development.

T cell development is fundamental to immune system establishment, yet how this development changes with age remains poorly understood. Here, we construct a transcriptional and epigenetic atlas of T cell developmental programs in neonatal and adult mice, revealing the ontogeny of divergent gene regulatory programs and their link to age-related differences in phenotype and function. Specifically, we identify a gene module that diverges with age from the earliest stages of genesis and includes programs that govern effector response and cell cycle regulation.

Functionalized nanowires for miRNA-mediated therapeutic programming of naïve T cells.

Cellular programming of naïve T cells can improve the efficacy of adoptive T-cell therapy. However, the current ex vivo engineering of T cells requires the pre-activation of T cells, which causes them to lose their naïve state. In this study, cationic-polymer-functionalized nanowires were used to pre-program the fate of primary naïve CD8 T cells to achieve a therapeutic response in vivo.