NFKB1 and infection: To determine if old murine BMMs displayed an abnormally high immune response to oral pathogenic infection that contributes to the high CD38 expression in old murine BMMs after infection with an oral pathogen, we quantified the protein levels of CD38 and some protein kinases (including NF-κB, PI3K, and MAPKs) by Western blot in old and young murine BMMs at various time points (1, 2, 4, 6, 8, and 24 h) after infection with Aa or Pg.