Expression of Six Possible Virulence Factors of C. pseudotuberculosis in Murine Macrophage

Abstract

Corynebacterium pseudotuberculosis is a gram-positive bacillus that causes caseous lymphadenitis in goats and sheep. Among its virulence factors are the pld proteins (Phospholipase D), cpp (Serine protease CP40), nanH (Neuraminidase H), sodC (Superoxide Dismutase C), spaC (Adesina SpaC) and pknG (Protein Kinase G). Objective: this study aimed to verify the transcription of these genes in macrophages of two lineage of mice infected in vitro with a virulent strain of C. pseudotuberculosis (CP1002), through the qRT-PCR technique. In parallel, the expression of pld, cpp, nanH, sodC and spaC genes in these same cells was also studied. Method: the total RNA from macrophages of C57BL/6 and Balb/c mice was extracted, and the complementary DNA was synthesized to the extracted RNA. The detection of messenger RNA from PknG, Pld, CP40, NanH, SodC and SpaC was obtained by quantitative PCR. Results: the six genes in infected mouse macrophages of Balb/c and C57BL/6 lineages were expressed in vitro in the three-time intervals (1, 12 and 24 hours after infection). The transcription intensity of pknG, pld, cpp, nanH, sodC and spaC genes one hour after infection appears to be greater than in the subsequent intervals, both in Balb/c macrophages and in C57BL/6 macrophages, although in the first cited all the genes show a supposedly accentuated transcript intensity in this interval. The pknG gene appears to have a more intense transcription magnitude than the others in both types of animals. Conclusion: the pknG, pld, cpp, nanH, sodC and spaC genes are transcribed into Balb/c and C57BL/6 macrophages, with apparently more pronounced expression in the first hour after infection in both types of cells. All genes appear to exhibit more intense transcription in Balb/c macrophages.