Miltefosine was the first oral compound approved for visceral leishmaniasis chemotherapy, and its efficacy against Leishmania donovani has been well documented. Leishmania amazonensis is the second most prevalent species causing cutaneous leishmaniasis and the main etiological agent of diffuse cutaneous leishmaniasis in Brazil. Driven by the necessity of finding alternative therapeutic strategi...

TO THE EDITOR—We appreciate Drs Torres and Suárez’s interest in our article, “High-Dose Oral Fluconazole Therapy Effective for Cutaneous Leishmaniasis Due to Leishmania (Vianna) braziliensis” [1]. They refer to evidence of Leishmania amazonensis isolated from human as well as domestic and wild reservoir hosts from the state of Ceará and suggest it is an important etiologic agent of cutaneous le...

Leishmaniasis is a highly diverse group of diseases caused by kinetoplastid of the genus Leishmania. These parasites are taxonomically diverse, with human pathogenic species separated into two subgenera according to their development site inside the alimentary tract of the sand fly insect vector. The disease encompasses a variable spectrum of clinical manifestations with tegumentary or visceral...

Most experimental studies on leishmaniasis compare two different inbred strains of mice that are resistant or susceptible to one species of Leishmania. In the present study we characterized some cytokines and nitric oxide production as well as histological changes related to resistance and susceptibility in isogenic CBA mice infected with Leishmania major or Leishmania amazonensis. CBA mice are...

During Leishmania major infection in mice, gamma interferon (IFN-gamma) plays an essential role in controlling parasite growth and disease progression. In studies designed to ascertain the role of IFN-gamma in Leishmania amazonensis infection, we were surprised to find that IFN-gamma could promote L. amazonensis amastigote replication in macrophages (Mphis), although it activated Mphis to kill ...

C3HeB/FeJ mice challenged with Leishmania major develop a polarized Th1 response and subsequently heal, whereas Leishmania amazonensis challenge leads to chronic lesions with high parasite loads at 10 weeks postinfection. In this study, a comparison of draining lymph node cells from L. amazonensis- and L. major-infected mice at 10 weeks postinfection showed equivalent percentages of effector/me...

Several antigens have been tested as vaccine candidates against Leishmania infections but controversial results have been reported when different antigens are co-administered in combined vaccination protocols. Immunization with A2 or nucleoside hydrolase (NH) antigens was previously shown to induce Th1 immune responses and protection in BALB/c mice against Leishmania donovani and L. amazonensis...

Cutaneous leishmaniasis associated with Leishmania amazonensis infection is characterized by uncontrolled parasite replication and profound immunosuppression; however, the underlying mechanisms remain largely unclear. One possibility is that the L. amazonensis parasite modulates antigen-presenting cells, favoring the generation of pathogenic Th cells that are capable of recruiting leukocytes bu...

Leishmania is an intracellular parasite in vertebrate hosts, including man. During infection, amastigotes replicate inside macrophages and are transmitted to healthy cells, leading to amplification of the infection. Although transfer of amastigotes from infected to healthy cells is a crucial step that may shape the outcome of the infection, it is not fully understood. Here we compare L. amazone...

This study evaluated two vaccine candidates for their effectiveness in protecting BALB/c mice against Leishmania chagasi infection. These immunogenic preparations were composed of Leishmania amazonensis or Leishmania braziliensis antigenic extracts in association with saponin adjuvant. Mice were given three subcutaneous doses of one of these vaccine candidates weekly for three weeks and four we...