PDCD1 and metabolic dysfunction-associated steatohepatitis: Gene set enrichment analysis (GSEA), mRNA in situ hybridization, and histology of tumours developed in NASH mice that were treated prophylactically with anti-PD1 corroborated these data, showing increased CD8+ T cell abundance and enrichment for genes involved in inflammation-related signalling, apoptosis, and TGFβ signalling (Extended Data Fig. 5j–l).