CD8A and neoplasm: These results showed that increased diversity and enrichment for Ruminococcaceae family bacteria correlate with improved response to anti-PD-1 and increases in CD8+ T cell activity (Gopalakrishnan et al., 2018) and that Bifidobacterium longum, Collinsella aerofaciens, and Enterococcus faecium may also augment responses by expanding tumor-specific CD8+ T cells without affecting Treg numbers (Matson et al., 2018).