Transcriptome analysis of murine macrophages infected with different strains of Leptospira spp

Leptospirosis is a neglected zoonotic disease of global importance. Despite its prevalence, pathogenesis is still poorly understood. Our aim was to discover transcripts responsable for pathogenicity of leptospirosis. We compared the transcriptome profiles of saprophyte, attenuated and virulent strain of Leptospira spp. Four treatments were performed in triplicates in J774A.1 macrophages in vitro, as follows: non-infected control cells and cells infected with virulent, attenuated and saprophyte strains of Leptospira. Following 6h of infection, total RNA was extracted and 250 ng of total RNA (RIN 10) was used to evaluate the mRNA profile using the microarray Affymetrix® Mouse Gene 2.1 ST Array Strips. Raw intensity values were background corrected, log2 transformed and then quantile normalized by the software Expression Console (Affymetrix) using the Robust Multi-array Average (RMA-Sketch) algorithm. Next, statistical analysis was performed in the TAC software (Affymetrix) by ANOVA (fold change ± 2, FDR-corrected p<0.01).