Frequency of epidermal langerhans cells in site of intradermal injection promastigotes of leishmania braziliensis in mice

ABSTRACT

We utilized inmunostaining assay with avidein boitin peroxidase technique and primary rat monoclonal antibody NLDC-145 specific for mouse dentritic cell, characterized langerhans cells (LC) in epidermis sheet of 1 mm² of skin of the footpads of inbred females BALB/c mice, intradermally (id) injected with 1.10ü cultured promastigotes of leishmania braziliensis. The result showed that the injection of the parasites in the skin of the animals produced a progressive increment of epidermal LC in the site of the previus injection, and statistically significant (P<0.05) in each study period. The density of epidermal LC was going up by parasite insult in early time, after the 15 minutes (m) post-infection (pi) with 162ñ31.2 LC/mm², reaching a maximal value of 4503ñ713 LC/mm² to 2 week (w) pi until 898ñ481 LC/mm² to 6 w pi. The number of LC was always higher in epidermis of the control healthy mice, these skin samples showed 120ñ28.9 LC/mm². Morphological changes of the promastigotes injected could to be detected in skin giemsa-stained imprints, the parasite showed form ovoid and a short flagel, between 15m and 2 hour (hr) pi. No parasites were even seen in the imprint samples than of as: activated macrfophages (33 percent) to 15 m pi, neutrophils (46,33 percent) to 4 hr pi, eosinophils (2,33 percent) to 4 hr pi, lymphocytes (15,67 percent) to 6 hr pi, degraded lymphocytes (8,33 percent) to 1 w pi, monocytes (4,33 percent) to 4 day (d) pi and activated monocytes (19,33 percent) to 1 d pi. The stained sections of skin inoculated, revealed amastigotes into macrophages dermal near of the perivascular area and inflammatory process in the dermis consisted of lymphocytes, monocytes, plasma cell and polymorphonuclear cells between 1 w and 6 w pi. No parasites were detected in the epidermis. the results showed that the promastigotes in the skin survived the first 2 hr out of the macrophages, and on the other hand, stinuled various cell types in sites of injection of the parasites, and the proliferation of antigen presentation by epidermalk langerhans cells, necessary for the initiation of the specific T cell inmune response