CD8A and pachyonychia congenita: Through human-to-mice fecal microbiota transplantation (FMT) experiments involving patients with PC with short survival (STS), patients who had PC resected more than 5 years previously showed no evidence of disease (LTS-NED), and in healthy controls (HC), research demonstrated that the favorable impact of LTS-NED-associated GI/tumor microbiota is mediated by CD8+ T cells [181].