title: A systems perspective of host-pathogen interactions: predicting disease outcome in tuberculosis.
abstract: The complex web of interactions between the host immune system and the pathogen determines the outcome of any infection. A computational model of this interaction network, which encodes complex interplay among host and bacterial components, forms a useful basis for improving the understanding of pathogenesis, in filling knowledge gaps and consequently to identify strategies to counter the disease. We have built an extensive model of the Mycobacterium tuberculosis host-pathogen interactome, consisting of 75 nodes corresponding to host and pathogen molecules, cells, cellular states or processes. Vaccination effects, clearance efficiencies due to drugs and growth rates have also been encoded in the model. The system is modelled as a Boolean network. Virtual deletion experiments, multiple parameter scans and analysis of the system's response to perturbations, indicate that disabling processes such as phagocytosis and phagolysosome fusion or cytokines such as TNF-alpha and IFN-gamma, greatly impaired bacterial clearance, while removing cytokines such as IL-10 alongside bacterial defence proteins such as SapM greatly favour clearance. Simulations indicate a high propensity of the pathogen to persist under different conditions.
authors.affiliation: Bioinformatics Centre, Indian Institute of Science, Bangalore - 560012, India. nchandra@serc.iisc.ernet.in.
authors.forename: Karthik
authors.initials: K
authors.lastname: Raman
authors.forename: Ashwini Gurudas
authors.initials: AG
authors.lastname: Bhat
authors.forename: Nagasuma
authors.initials: N
authors.lastname: Chandra
mesh_terms: D003198:Computer Simulation; D016207:Cytokines / Q000235:genetics; D055786:Gene Knockout Techniques; D054884:Host-Pathogen Interactions / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D006801:Humans; D055633:Immune System Phenomena; D008954:Models, Biological; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D015398:Signal Transduction; D049490:Systems Biology / Q000379:methods*; D014376:Tuberculosis / Q000276:immunology / Q000378:metabolism / Q000382:microbiology*; D037521:Virulence Factors
chemical_list: D016207:Cytokines; D037521:Virulence Factors