Healed Lesions of Human Cutaneous Leishmaniasis Caused By Do Not Shelter Persistent Residual Parasites.

In human cutaneous leishmaniasis (HCL) caused by () , the cutaneous lesions heal spontaneously and induce a Th1-type immunity that confers solid protection against reinfection. The same holds true for the experimental leishmaniasis induced by in C57BL/6 mice where residual parasites persist after spontaneous clinical cure and induce sustainable memory immune responses and resistance to reinfection. Whether residual parasites also persist in scars of cured HCL caused by is still unknown.

Intra-Specific Diversity of Isolates: A Key Determinant of Tunisian Zoonotic Cutaneous Leishmaniasis Clinical Polymorphism.

The clinical expression of zoonotic cutaneous leishmaniasis (ZCL) caused by () parasites has a broad spectrum ranging from asymptomatic infection to self-limited cutaneous sores or severe disease. In concert with the host immune responses, the vector variability and the number of bites, genetic variation between isolates might impact on the clinical output of the disease. We investigated herein the intra-specific variability of field isolates independently of host or vector factors and then tried to correlate parasite variability to ZCL severity in corresponding patients.

A prospective cohort study of Cutaneous Leishmaniasis due to Leishmania major: Dynamics of the Leishmanin skin test and its predictive value for protection against infection and disease.

Background: Leishmanin Skin Test (LST) is considered as a useful indicator of past infection by Leishmania parasites. However, the temporal dynamics of a positive LST under different epidemiologic scenarios and whether it relates to the protection against the recurrence of an overt disease are not fully documented.

Methodology/principal Findings: We report here on a population based prospective study conducted on 2686 individuals living in two foci located in Central Tunisia, to assess over a one-year epidemiologic season, the incidence of Leishmania (L.

Genetic micro-heterogeneity of Leishmania major in emerging foci of zoonotic cutaneous leishmaniasis in Tunisia.

Tunisia is endemic for zoonotic cutaneous leishmaniasis (ZCL), a parasitic disease caused by Leishmania (L.) major. ZCL displays a wide clinical polymorphism, with severe forms present more frequently in emerging foci where naive populations are dominant.

Human cellular immune response to the saliva of Phlebotomus papatasi is mediated by IL-10-producing CD8+ T cells and Th1-polarized CD4+ lymphocytes.

Background: The saliva of sand flies strongly enhances the infectivity of Leishmania in mice. Additionally, pre-exposure to saliva can protect mice from disease progression probably through the induction of a cellular immune response.

Methodology/principal Findings: We analysed the cellular immune response against the saliva of Phlebotomus papatasi in humans and defined the phenotypic characteristics and cytokine production pattern of specific lymphocytes by flow cytometry.

Characterization of the antibody response to the saliva of Phlebotomus papatasi in people living in endemic areas of cutaneous leishmaniasis.

Important data obtained in mice raise the possibility that immunization against the saliva of sand flies could protect from leishmaniasis. Sand fly saliva stimulates the production of specific antibodies in individuals living in endemic areas of parasite transmission. To characterize the humoral immune response against the saliva of Phlebotomus papatasi in humans, we carried out a prospective study on 200 children living in areas of Leishmania major transmission.