In vitro insights of Leishmania (Viannia) species related to their outcomes and virulence in American tegumentary leishmaniasis

• DOI: 10.22533/at.ed.1592127091

• Palavras-chave: Leishmaniose cutanea, leishmaniose do novo mundo, virulência, Lleishmania, hospedeiro-parasita-interação, metaloprotease

• Keywords: cutaneous leishmaniasis; new world leishmaniasis; virulence; Leishmania; host-parasite interactions; metalloproteases

• Abstract:

  Different Leishmania species cause cutaneous leishmaniasis. Leishmania (Viannia) braziliensis [L(V)b] is responsible for the cutaneous and mucosal form, while L. (V.) lainsoni [L(V)l] and L. (V.) naiffi [L(V)n] are associated with the cutaneous one only, and the latter is responsible for self-healing. Since these mechanisms are not fully understood, we investigated in vitro aspects of these species that could be related to their different leishmaniasis outcomes. Three strains of L(V)b, one strain of L(V)n and one from L(V)l were selected for this study. The morphologies of the Leishmania species were observed. The activity of peptidases present into the membrane of promastigote forms of Leishmania spp. and in the supernatant of macrophages infected by Leishmania spp. were studied by the zymographic and inhibition assay. The infectiveness in vitro of each Leishmania spp. was evaluated in macrophages J774A.1 at 0h and 24h post-infection. The results showed that these parasites have different body lengths, forms, the activity of promastigote cell-related metalloproteases and metalloproteases secreted by macrophages in response to the infection. Low expression of Leishmania peptidases may be associated with the cure after the treatment in L(V)b strains. Pro-metalloproteinase 2 seems to be related with more complicated cases of cutaneous leishmaniasis. L(V)n has the lowest infection index in macrophages. These species have differences in parasite constitution and host interaction that may explain their clinical manifestation in humans and further studies can contribute to the elucidation of new drug targets and biomarkers.

• Número de páginas: 29