Critical injury in humans induces a genomic storm with simultaneous changes in expression of innate and adaptive immunity genes.

Regulatory T cells (Treg) play a central role in counteracting inflammation and autoimmunity. A more complete understanding of cellular heterogeneity and the potential for lineage plasticity in human Treg subsets may identify markers of disease pathogenesis and facilitate the development of optimized cellular therapeutics. To better elucidate human Treg subsets, we conducted direct transcriptional profiling of CD4+FOXP3+Helios+ thymic-derived Treg (tTreg) and CD4+FOXP3+Helios− T cells, followed by comparison to CD4+FOXP3−Helios− T conventional (Tconv) cells. These analyses revealed that the coinhibitory receptor T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) was highly expressed on tTreg. TIGIT and the costimulatory factor CD226 bind the common ligand CD155. Thus, we analyzed the cellular distribution and suppressive activity of isolated subsets of CD4+CD25+CD127lo/− T cells expressing CD226 and/or TIGIT. We observed TIGIT is highly expressed and upregulated on Treg following activation and in vitro expansion and is associated with lineage stability and suppressive capacity. Conversely, the CD226+TIGIT− population was associated with reduced Treg purity and suppressive capacity following expansion, along with a marked increase in IL-10 and effector cytokine production. These studies provide additional markers to delineate functionally distinct Treg subsets that may help direct cellular therapies and provide important phenotypic markers for assessing the role of Treg in health and disease.

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GCRI gene function is required for high-level glycolytic gene expression in Saccharomyces cerevisiae.Recently, we suggested that the CTTCC sequence motif found in front of many genes encoding glycolytic enzymes lay at the core of the GCR1-binding site. Here we mapped the DNA-binding domain of GCR1 to the carboxy-terminal 154 amino acids of the polypeptide. DNase I protection studies showed that a hybrid MBP-GCR1 fusion protein protected a region of the upstream activating sequence of TPI (UASTpI), which harbored the CTTCC sequence motif, and suggested that the fusion protein might also interact with a region of the UAS that contained the related sequence CATCC. A series of in vivo G methylation protection experiments of the native TPI promoter were carried out with wild-type and gcrl deletion mutant strains. The G doublets that correspond to the C doublets in each site were protected in the wild-type strain but not in the gcrl mutant strain. These data demonstrate that the UAS of TPI contains two GCRl-binding sites which are occupied in vivo. Furthermore, adjacent RAPl/GRFI/TUF-and REB1/GRF2/QBP/Y-binding sites in UASTp, were occupied in the backgrounds of both strains. In addition, DNA band-shift assays were used to show that the MBP-GCR1 fusion protein was able to form nucleoprotein complexes with oligonucleotides that contained CTTCC sequence elements found in front of other glycolytic genes, namely, PGK, ENO], PYK, and ADHi, all of which are dependent on GCRI gene function for full expression. However, we were unable to detect specific interactions with CTTCC sequence

The African spiny mouse (Acomys spp.) can heal full thickness excisional skin wounds in a scar-free manner with regeneration of all dermal components including hair and associated structures. Comparing Acomys scar-free healing from Mus scarring identifies gene expression differences that discriminate these processes. We have performed an extensive comparison of gene expression profiles in response to 8mm full-thickness excisional wounds at days 3, 5, 7 and 14 post-wounding between Acomys and Mus to characterize differences in wound healing, and identify mechanisms involved in scar-free healing. We also identify similarities with scar-free healing observed in fetal wounds. While wounding in Mus elicits a strong inflammatory response, wounding in Acomys produces a moderated immune response and little to no increase in expression for most cytokines and chemokines assayed. We also identified differences in the ECM profiles of the Acomys wounds, which appear to have a collagen profile more similar to fetal wounds, with larger increases in expression of collagen types III and V. In contrast, Mus wounds have very high levels of collagen XII. This data suggests that an overall lack of induction of cytokines and chemokines, coupled with an ECM profile more similar to fetal wounds, may underlie scar-free wound healing in Acomys skin. These data identify candidate genes for further testing in order to elucidate the causal mechanisms of scar-free healing.