Hypertrophic scars (HTS) are a common complication of burn injuries and are characterized by excessive dermal fibrosis driven by the transformation of resident dermal fibroblasts to profibrotic myofibroblasts. Although single cell and bulk RNA transcriptomics analysis of HTS and normal skin tissue samples were performed previously, transcriptomics of the transformation of fibroblasts to myofibroblasts has not been studied. Here, we report the data obtained from RNA sequencing of fibroblasts before and after exposure to transforming growth factor beta 1 (TGF-β1) and highlight the pathways that are up- and down-regulated during myofibroblast transformation. Our results suggest increased cellular signalling and rewiring, proliferative surge, immune-like and metabolic reprogramming, and delayed structural remodelling as four groups of events during the transformation of human primary dermal fibroblasts to myofibroblasts.
Chronic alcohol consumption induces the pathogenic activation of hepatic stellate cells (HSC) and their conversion into proliferative myofibroblasts (Myo), which together constitute a disease hub in alcohol-associated liver disease (AALD). While natural killer (NK) lymphocytes efficiently target early activated HSC and ameliorate liver fibrosis in mouse models of diet- and alcohol-induced liver disease, late-activated HSC evade immune surveillance. To gain insight into evasive resistance mechanisms, we profiled the expression of immunoregulatory ligands by HSC and showed that HSC dynamically express CD80, a B7-family ligand that suppresses NK and T cell responses. Using a mouse model of acute-on-chronic alcohol consumption, we show that combined blockade of the CTLA-4//TIGIT/PD-1 inhibitory checkpoints overcomes this resistance mechanism, promoting the selective elimination of activated HSC (aHSC)/Myo, yet fails to diminish fibrosis or ameliorate liver function. Single-cell transcriptome profiling of liver non-parenchymal cells revealed that checkpoint blockade promotes hepatic infiltration of pro-fibrotic Th1 and Th17 T cell subpopulations, while decreasing immunosuppressive Treg. Strikingly, antibody-directed engagement of the PD-1 and TIGIT checkpoints also fails to reduce fibrosis or improve liver function. Thus, selective targeting of aHSC/Myo may be necessary to achieve significant therapeutic benefit.