PTGS2 and infection: A thorough review of candidate gene function, infection kinetics, and the immunologic response to B. suis infection reduced the number of putative candidate genes from 40 to three:(1) acyloxyacyl hydrolase (AOAH), (2) engulfment and cell motility 1 (ELMO1), and (3) prostaglandin synthase 2 (PTGS2).