the leishmania major parasite surface antigen-2 (psa-2) is a family of glycoinositol phospholipids anchored glycoprotoins expressed in both promastigotes and amastigotes. promastigote psa-2 comprises three polypeptides with approximate molecular weight of 96, 80 and 50 kda. amastigote express a distinct but closely psa-2 polypeptide with molecular weight of 50 kda. in this study fusion of sp2/0...

Leishmaniasis is a group of diseases caused by protozoan parasites of the Leishmania genus. Previous studies have shown that a DNA vaccine encoding Leishmania donovani antigen nucleoside hydrolase 36 and L. mexicana glycoprotein 63 is protective in mice. We investigated here the efficacy of this DNA vaccine to induce protection in golden hamsters. Male hamsters were more susceptible to infectio...

Activated natural killer (NK) cells release interferon (IFN)-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major,...

Visceral leishmaniasis, a disease caused by Leishmania infantum chagasi, represents a major public health problem in many areas of the world. However, there is currently no vaccine for human use. The aim of this work was to purify the 503 antigen of Leishmania i. chagasi directly from unclarified Escherichia coli feedstock through expanded bed adsorption (EBA) chromatography. Batch experiments ...

Membrane-associated Leishmania Ags (MLA) or soluble Leishmania Ags were used in vitro to stimulate cord blood or PBMC from healthy donors noninfected by Leishmania parasites. MLA, but not soluble Leishmania Ags, constantly induce strong proliferation of cord blood mononuclear cells and PBMC from noninfected individuals. Responding cells are CD3+, CD4+, TCRalphabeta+, CD45RO+, and CD45RA+ and se...

in this study, a crude leishmanial antigen, was prepared by sonicating leishmania major promastigotes used to induce immunity in balb/c mice against cutaneous leishmaniasis. correlation between the route of antigen injection and the efficacy of induced protection was examined. to enhance the effectiveness of the antigen, an immunostimulant drug, daraprim (pyrimethamine), was administered simult...

BACKGROUND An important issue associated with the control of visceral leishmaniasis is the need to identify and understand the relevance of asymptomatic infection caused by Leishmania infantum. The aim of this study was to follow the course of asymptomatic L. infantum infection in children in an area of Brazil where it is endemic. The children were assessed twice during a 12-month period. MET...