GAPDH and infection: To assess the upregulation of inflammatory cytokines critical for immune responses and fibrosis markers associated with kidney damage, kidney was collected from experimental mice on day 15 post-infection and processed for mRNA expression analysis of TNF-α, TGF- β1, IL-1β, IFN-γ, IL-6, IL-23, IL-17a, iNOS and ColA1 by RT-PCR using glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as the calibrator to normalize gene expression.