Journal of Bacteriology & Parasitology

Immune responses to Mycobacterium avium infection and the role of MAPK pathway in regulation of signal transduction during the infection

3^rd International Congress on Bacteriology and Infectious Diseases

August 04-06, 2015 Valencia, Spain

Mohammed Shukur, Sabine Tötemeyer, Nawzat Issa, Paul Barrow and Michael A Jones

Scientific Tracks Abstracts: J Bacteriol Parasitol

Abstract:

Mycobacterial infection is a major problem in both human and animal health. Several cell signaling pathways are involved
in the mediation of expression of a number of cytokines induced by mycobacterial infection. The mitogen activated
protein kinase (MAPK) pathway plays a crucial role in the pathogenesis of mycobacterial infection. In this study we aimed
to evaluate the role of ERK and p38 MAPK in cellular regulation by Mycobacterium avium infection in human and chicken
macrophages-like cells. THP-1 and HD11 cells were infected with eight clinical isolates of Mycobacterium avium. The cells
were pre-treated with highly specific inhibiters of the ERK (PD98059 or U0126) and p38 (SB203580) pathways 30 min prior to
infection and the levels of cytokine production at 6 and 24 hour post infection were assessed using ELISA and RT-qPCR. M.
avium infection resulted in differential expression of cytokines and chemokines in THP-1 and HD11 cells. Treatment of the
cells with PD98059 or U0126 inhibited production of cytokines in THP-1 and completely blocked their expression in HD11
cells. In addition, p38 inhibition differentially modulated cytokine production in THP-1 cells compared to non-inhibited
M. avium-infected cells. It inhibited release of IL-6 while the level of IL-1β and TNF-α showed an increase in THP-1 cells in
response to M. avium infection following treatment of the cells with SB203580. The results suggest that signalling events are
significantly different in avian and human cells following M. avium infection. Both p38 and ERK are involved in regulation of
IL-6 production while p38 negatively regulates IL-1β and TNF-α production in response to M. avium in THP-1 cells. In HD11
cells, it is suggested that multiple signal pathways simultaneously participate in regulation of cytokine signal transduction
during M. avium infection.

Biography :

Mohammed Shukur is currently a PhD student in School of Veterinary Medicine and Science, University of Nottingham, UK. He has completed his MSc from School
of Veterinary Medicine University of Duhok, Iraq.