Trypanosoma cruzi amastigotes present receptors for human transferrin as indicated by the saturable binding of 125I-transferrin to this form of the parasite. Computerized Scatchard analysis revealed one class of receptors present at 8.1 X 10(4) receptors per amastigote with a Kd of 2.82 microM. Immunofluorescence studies indicate that more than 90% of amastigotes bind human transferrin, whereas...

balb/c mice are highly susceptible to infection with the protozoan parasite leishmania major. this susceptibility has been attributed in part to the expansion of th2 cells and production of their cytokines, il-4 and il-10 and down-regulation of th1 cytokine, inf-γ. the inability of susceptible hosts to mount the immune response necessary to activate macrophage and destroy the parasites can be d...

Antitrypanosomal activity of chloroform extract of Senna villosa leaves was evaluated in the sub acute phase of mice infected with Trypanosoma cruzi. Oral doses of 3.3, 6.6 and 13.2 µg/g were tested during 15 days on infected mice BALB/c, beginning treatment 40 days after infection to evaluate specifically the antitrypanosomal activity over the amastigote form of the parasite. Two different amo...

The onset of infections by Leishmania parasites mainly caused by amastigote growth inside the macrophages. One of the important properties of lesion-derived amastigote is thought to be the attachment of various host proteins including immunoglobulins on the surface of amastigote. In this study, the presence of immunoglobulins on the surface of lesion-derived amastigotes was detected by Western ...

This study was performed in order to define the cellular immune response of 12 recovered cutaneous leishmaniasis subjects to different soluble antigens of the amastigote form of Leishmania major. A soluble leishmanial antigen preparation (SLA) derived from highly-purified amastigotes from infected nude mice was fractionated by Mono Q column using Fast Protein Liquid Chromatography (FPLC) s...

this study was carried out to identify the efficacy of caparis spinosa root extract on promastigotes and amastigotes of leishmania major . caparis spinosa extracts were prepared. promastogotes of  l.major (1×10 6 parasites/ml)were incubated at 26 ºc for 24,48 and 72hours in fresh medium(nnn), in absence or presence of different concentrations (0.1,0.3,0.5,0.7,0.9 mg/ml) of caparis spinosa metha...

A massive and homogeneous amount of amastigote-like forms was detected in the stomodeal valve (SV) and the thoracic mid-gut (TMG) of Leishmania major-infected Phlebotomus papatasi, which received a second blood meal 13 to 21 days post-infection on healthy anaesthetized hamsters. After re-feeding, the infected sand flies were dissected out to examine the morphology of the parasite in SV, TMG and...

This work aims at identifying an effective protocol to raise anti-Leishmania chagasi amastigote antibodies in different animal species. Protocols of immunization by subcutaneous injections of L. chagasi promastigote and amastigote lysates or by either intravenous or subcutaneous inoculation of live metacyclic promastigotes were assessed in mice, rabbits, and dogs. The immunization with live pro...

The parasitic protozoan Leishmania alternates between an invertebrate and a mammalian host. Upon their entry to mammalian macrophages, Leishmania promastigotes differentiate into amastigote forms within the harsh environment of the phagolysosomal compartment. Here, we provide evidence for the importance of translational control during the Leishmania differentiation process. We find that exposur...