Outbreak Multi-drug resistant Strains of M. tuberculosis (Mtb) induce differential IL-8 secretion from human bronchial epithelial cells altering therefore polymorphonuclear cells (PMN) chemotaxis

KVIATCOVSKY D; BALBOA L; LANDONI V; COUGOULE C ; LOPEZ B; MARIDONNEAU-PARINI I; SASIAIN MC; DE LA BARRERA S

Congreso; IV Lasid Meeting, LXII SAI, II French Argentinean Immunology Meeting,; 2015

Mtb infects the lung by interacting with airway epithelium and resident macrophages. The epithelium not only constitutes an anatomical barrier for bacterial invasion but also responds to pathogens by producing anti-microbial molecules, proinflammatory cytokines and chemokines like IL-8 that recruit macrophages and PMN in order to mount an early inflammatory response and control the infection. Besides, metalloproteinases play an important role in Mtb-induced-tissue destruction and enhance the recruitment of macrophages contributing to granuloma formation and control of bacterial expansion. Objectives: We evaluated whether Mtb strains induce differential secretion of IL-8 and metalloproteinases by Calu-6 cells, PMN chemoattractant activity and PMN adherence to the bronchial epithelium. Results: i) Lower IL-8 secreted levels were detected in M- stimulated Calu-6 supernatants than H37Rv-stimulated; ii) M-stimulated Calu-supernatants induced lesser chemoattraction of PMN than H37Rv; iii) PMN adherence to Calu-6 showed no differences between strains; iv) not only macrophages secrete MMP?s in the presence of Mtb but also alveolar epithelial cells that were stimulated with those macrophages supernatants (CoMtb), secrete MMP-9 and MMP-2, but we have seen no differences between strains. Conclusions: Mtb strains could differentially stimulate Calu-6 which results in a lower PMN chemoattraction associated to lower IL-8 levels triggered by the M strain