CXCL2 and infection: To explore the effects of UP ascending infection on inflammation, protein levels (enzyme-linked immunosorbent assay (ELISA)) of TNFα and (C–X–C motif) ligand 2 (CXCL-2), and mRNA expression (quantitative PCR (qPCR)) of the pro-inflammatory cytokines TNFα, IL-1β, CXCL-1, CXCL-2 or IL-6 were examined in the placenta, myometrium, foetal membranes and foetal lung in frozen tissue collected at 48 hpi.