Involvement of NF-κB and MAP-kinases in the transcriptional response of alveolar macrophages to

Astrid de Greeff , Laurentiu Benga , Paul J. Wichgers Schreur , Peter Valentin-Weigand , Johanna M.J. Rebel , Hilde E. Smith

Interaction of with primary porcine alveolar macropahges was studied using transcriptomics. Transcriptional response of macrophages to two different strains was studied: wild-type S10 that is resistant to phagocytosis, and it non encapsulated mutant that is phagocytosed efficiently. The macrophages' transcriptional response was observed only after 60minutes of incubation. Eleven genes were expressed significantly different between macrophages infected with streptococci and control mock-infected macrophages. These genes include IL-1-ß, MIP-2-α and TNF-α. When gene expression was studied as function of time, transcriptional changes occurred in all macrophages independent of streptococci. The fold induction of induced genes however, was much stronger in macrophages incubated with the non-encapsulated strain that was phagocytosed. The genes that were higher induced due to suggest an innate immune response is induced in macrophages. Pathway analysis revealed that genes that are part of the putative MAP-kinase signal transduction system are overrepresented among the regulated genes. Using an immortalized alveolar macrophage cell line it was shown that macrophages respond to interaction with by translocation of NF-κB to the nucleus, independent of phagocytosis. This translocation subsequently induced expression of innate immune genes. This strongly suggests besides the MAP-kinase signaling pathway, NF-κB signaling is also induced upon interaction with .

Mots clés: Transcriptional response; Macrophages

Astrid de Greeff, Laurentiu Benga, Paul J. Wichgers Schreur, Peter Valentin-Weigand, Johanna M.J. Rebel, et al.. Involvement of NF-κB and MAP-kinases in the transcriptional response of alveolar macrophages to. Veterinary Microbiology, 2010, 141 (1-2), pp.59. ⟨10.1016/j.vetmic.2009.07.031⟩. ⟨hal-00560842⟩