PCV2 infection upregulates pDNAJB6 expression in PK-15 cells. A–C PK-15 cells were infected with 1 MOI of PCV2 or mock infection for indicated time, the mRNA level of pDNAJB6 (A), the protein level of pDNAJB6 (B) and the relative viral titers of different infected time were measured by TCID50 (C). D, E qPCR and Western blot analysis of pDNAJB6 mRNA and protein levels in PK-15 cells infected with different doses of PCV2 (MOI = 0, 0.5, 1, or 5) for 36 h. β-actin served as an internal control. Results are shown as the mean ± SD (n = 3). *p < 0.05, **p < 0.01 versus mock infected cells at same time points; #p < 0.05, ##p < 0.01 versus cells infected with PCV2 for 24 h.