GZMA and infection: On the other hand, the network model for the downregulated genes (sFig. 4b) showed that UCB-MSCs predominantly upregulated the pathways induced by pathogen infections, which were downregulated by MCT, including complement cascade (Fcnb and C4bpa), NK cell activation (Klrb1a/c, Spon2, and Slit2), cytotoxic T cell-mediated cell killing pathways-MHC1 class 1 presentation (RT1-A/A1, RT1-CE2/3/4/12/14/15/16, RT1-S2/3, and Tap1/2), and killing of target cells (Gzma/b/c/k/m, and Prf1).