GRHL2 suppresses EMT to give a default epithelial phenotype. GRHL2 inhibits this process through the histone acetyltransferase coactivator p300, repressing the partial EMT and preventing induction of MMPs. The results demonstrate novel roles for p300 and GRHL2 in promoting or suppressing EMT in morphogenesis and tumor progression.
Aging profoundly affects immune system function, rendering the elderly more susceptible to pathogens, cancers and chronic inflammation. We previously identified a population of IL-10-producing, T follicular helper-like cells ("Tfh10"), linked to suppressed vaccine responses in aged mice. Here, we use the power of single-cell (sc)genomics and genome-scale modeling to characterize Tfh10 — and the full CD4+memory T cell (CD4+TM) compartment — in young and old mice. Unprecedented scRNA-seq coverage of the CD4+TM compartment and parallel chromatin accessibility measurements (scATAC-seq) enabled identification of 13 CD4+TM populations, which we validated as a reference through comprehensive cross-comparison to aging cell atlases and scRNA-seq studies reporting Tfh10 in other contexts. Beyond robust characterization of age- and cell-type-dependent transcriptional landscapes, we used integrative computational modeling to predict the underlying regulatory mechanisms: We inferred gene regulatory networks (GRNs) that describe transcription-factor control of gene expression in each T-cell population and how these circuits change with age. Furthermore, we integrated our data with prior, pan-cell scRNA-seq studies to identify intercellular-signaling networks driving age-dependent changes in CD4+TM. Our atlas of finely resolved CD4+TM subsets, GRNs and cell-cell communication networks is a critical resource for analysis of biologic processes operative in memory T cells in youth and old age. The resource presents new opportunities to manipulate regulatory circuits in CD4+TM, which, long-term, could improve immune responses in the elderly.
Aging and obesity are two conditions characterized by chronic, low-grade inflammation. While both conditions are also associated with dysfunctional immune responses, the shared and distinct underlying mechanisms are just starting to be uncovered. In fact, recent findings have suggested that the effects of obesity on the immune system can be thought of as a state of accelerated aging. Here we propose that chronic, low-grade inflammation seen in obesity and aging is complex, affects multiple cell types, and results in an altered basal immune state. In aging, part of this altered state is the emergence of regulatory immune populations that lead to further immune dysfunction in an attempt to reduce chronic inflammation. While in obesity, part of the altered state is the effect of expanding adipose tissue on immune cell function. Thus, in this review, we compare, and contrast altered immune states in aging and obesity and discuss their potential contribution to a shared clinical problem- decreased vaccine responsiveness.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.