Browsing by Subject "zebrafish"

Tuberculosis (TB) still ranks as one of the most dangerous infectious diseases around the world and it is accountable for over 1.5 million deaths every year. World Health Organization has estimated that one fourth of the world’s population is infected with Mycobacterium tuberculosis. The current treatment against TB has drawbacks and the only available vaccine against TB does not provide sufficient protection against the disease and therefore new treatments are much needed. There has also been a lack of good animal models, but the zebrafish (Danio rerio) have been recently found to be a good model to study especially granuloma formation, latency, and reactivation of TB. Their natural pathogen, Mycobacterium marinum causes similar infection in the fish than M. tuberculosis in humans. One characteristic of TB is the formation of granulomas, which are aggregates of immune cells that contain the bacteria. However, M. tuberculosis can escape the granuloma and in such a way spread in the host. The inflammasome is an innate immune system mechanism that activates the immunological response in an infection and has a role in the formation of granulomas. PYCARD is an adaptor protein that has a role in inflammasome activation, which makes it an interesting target when studying the immunological response against M. tuberculosis infection. In this study, granuloma formation in pycard-/- and pycard+/+ zebrafish were compared. The granulomas were studied for their size, location, structure and hypoxicity, and the number of granulomas in each fish was counted. Also, the number of free bacteria was assessed. No significant differences were found in any of these aspects between pycard-/- and pycard+/+ fish. Variation between individual fish was great in both groups.