CHM and infection: At the later stage of infection (48 h p.i.), p-p38-MAPK was detected in the PCV1-Rep2-infected cells, but the level of p-p38-MAPK was lower in PCV1-Rep2-infected cells than that in PCV2- and PCV2-Rep1-infected cells and the level of p-p38-MAPK in the PCV2-Rep1-infected cells was lower than that in the PCV2-infected cells (Figure 5A,B).