Cell biology of Leishmania spp.: invading and evading.

Parasitic protozoa of the genus Leishmania infect mammalian mononuclear phagocytic cells causing a potentially fatal disease with a broad spectrum of clinical manifestations. The drugs of choice used in the leishmaniasis therapy are significantly toxic, expensive and faced with a growing frequency of refractory infections. Thus the search for new leishmanicidal compounds is urgently required. In order to perform a proper drug design and to understand the modes of action of such compounds it is necessary to elucidate the intricate cellular and molecular events that orchestrate the parasite biology. In order to invade the host cell Leishmania are able to recruit different surface receptors which may assist engaging the microbicidal responses. In the intracellular milieu these pathogens can deactivate and/or subvert the phagocyte signal transduction machinery rendering these cells permissive to infection. In the present review we attempted to approach some of the most relevant cellular and biochemical invasion and evasion strategies employed by Leishmania parasites.