CD4 and Abnormal emotional state: In addition, psychological distress attenuates tumor-infiltrating CD8+ T cells function by decreasing Blautia and acetic acid.53 Interestingly, we find that A. muciniphila reverses stress-induced CD4+ T cell proliferation and differentiation of Th2, Treg cells, while rescuing stress-inhibited CD4+ Th1 cell differentiation (data not shown).