Vaccination with Leishmania histone H1-pulsed dendritic cells confers protection in murine visceral leishmaniasis.

Visceral leishmaniasis is the most severe form of leishmaniases affecting millions of people worldwide often resulting in death despite optimal therapy. Thus, there is an urgent need for the development of effective anti-infective vaccine(s). In the present study, we evaluated the prophylactic value of bone marrow-derived dendritic cells (BM-DCs) pulsed with the Leishmania (L.

Leishmania histone H1 overexpression delays parasite cell-cycle progression, parasite differentiation and reduces Leishmania infectivity in vivo.

Episomal expression of Leishmania histone H1 sense mRNAs in Leishmania major promastigotes was found previously to result in overexpression of this molecule and to reduce parasite infectivity in vitro. Herein, we evaluated the in vivo infectivity of these transfectants, in BALB/c mice, and showed that it is dramatically reduced. No lesions were observed in this group of mice and this was associated with an extremely low number of parasites both in the footpad and in the draining lymph nodes.

Expression of a novel Leishmania gene encoding a histone H1-like protein in Leishmania major modulates parasite infectivity in vitro.

We describe identification and characterization of a novel two-copy gene of the parasitic protozoan Leishmania that encodes a nuclear protein designated LNP18. This protein is highly conserved in the genus Leishmania, and it is developmentally regulated. It is an alanine- and lysine-rich protein with potential bipartite nuclear targeting sequence sites.