target cells in leishmania major as the causative agent of cutaneous leishmaniasis

Leishmaniasis is still a neglected tropical disease that can endanger more than 350 million people among 100 countries. leishmania can survive in macrophages, fibroblasts and some unknown cells as latent inactive forms. the structure of the skin is composed of three main layers: epidermis, dermis and hypodermis. this protozoon parasite is able to enter other cell types, such as amniotic epithelial cells, kidney cells, neutrophils, eosinophils, keratinocytes and dendritic cells as latent inactive forms. it was found that human fibroblast can uptake l. braziliensis, l. major and l. donovani promastigotes and l. amazonensis amastigotes. in recent studies, it has been determined that after the artificial inoculation of the parasite to the host s skin or the natural transmission of the parasite with the bite of phlebotomus or lutzomia sandflies, neutrophils are the first cells present at the entry site of leishmania species and phagocytose the parasites. although some leishmania are killed by neutrophils, some survive within neutrophils until apoptosis. uptake of infected neutrophils by macrophages leads to mertk signaling and increased tgfβ release, which induces an anti-inflammatory macrophage state and intracellular parasite proliferation. in a study was done based nimad grant no. 996647 cell culture of the hacat cell line of keratinocyte and the foreskin cell culture for human fibroblast were prepared. these cell cultures, co-cultured with dil labeled l. major separately for 6, 8, 24 hours and followed by fluorescence microscopic assay. according to the obtained results, the presence of parasites stained with vital dye in fibroblasts and keratinocytes, confirmed the importance of these cells as target for their hiding in the host. these findings can open a new window in diagnosis, pathogenesis and treatment of cutaneous leishmaniasis.