GBP4 and infection: Guanylate binding protein 4 gene (GBP4) PBMC expression profiles for the N'Dama and Boran were synchronized after infection, with an early highly significant peak in expression at 14 dpi (3.3-fold, P = 0.0002 in N'Dama and 2.6-fold, P = 0.0029 in Boran) followed by a reduction in expression in both breeds.