Review Article Plasminogen Binding Proteins and Plasmin Generation on the Surface of Leptospira spp.: The Contribution to the Bacteria-Host Interactions

Copyright © 2012 Monica L. Vieira et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Leptospirosis is considered a neglected infectious disease of human and veterinary concern. Although extensive investigations on host-pathogen interactions have been pursued by several research groups, mechanisms of infection, invasion and persistence of pathogenic Leptospira spp. remain to be elucidated. We have reported the ability of leptospires to bind human plasminogen (PLG) and to generate enzimatically active plasmin (PLA) on the bacteria surface. PLA-coated Leptospira can degrade immobilized ECM molecules, an activity with implications in host tissue penetration. Moreover, we have identified and characterized several proteins that may act as PLG-binding receptors, each of them competent to generate active plasmin. The PLA activity associated to the outer surface of Leptospira could hamper the host immune attack by conferring the bacteria some benefit during infection. The PLA-coated leptospires obstruct complement C3b and IgG depositions on the bacterial surface, most probably through degradation. The decrease of leptospiral opsonizationmight be an important aspect of the immune evasion strategy.We believe that the presenc