Susceptibilidad de diferentes especies de Rhodnius (Hemiptera, Reduviidae, Triatominae) a una cepa brasileña de Trypanosoma rangeli (SC58/KP1-)

Abstract

Introduction: Specific host-parasite associations have been detected experimentally and suggest that triatomines of the genus Rhodnius act as biological filters in the transmission of Trypanosoma rangeli. Objective: To analyze the susceptibility of four Rhodnius species (Rhodnius robustus, Rhodnius neglectus, Rhodnius nasutus and Rhodnius pictipes) to a Brazilian strain of T. rangeli (SC-58/KP1-). Materials and methods:We selected thirty nymphs of each species, which were fed on blood infected with T. rangeli. Periodically, samples of feces and hemolymph were analyzed. Triatomines with T. rangeli in their hemolymph were fed on mice to check for transmission by bites. Later, the triatomines were dissected to confirm salivary gland infection. Results: Specimens of R. pictipes showed higher rates of intestinal infection compared to the other three species. Epimastigotes and trypomastigotes were detected in hemolymph of four species; however, parasitism was lower in the species of the R. robustus lineage. Rhodnius robustus and R. neglectus specimens did not transmit T. rangeli by bite; after dissection, their glands were not infected. Only one specimen of R. nasutus and two of R. pictipes transmitted the parasite by bite. The rate of salivary gland infection was 16% for R. pictipes and 4% for R. nasutus. Conclusions: Both infectivity (intestinal, hemolymphatic and glandular) and transmission of T. rangeli (SC58/KP1-) were greater and more efficient in R. pictipes. These results reinforce the hypothesis that these triatomines may act as biological filters in the transmission of T. rangeli.

Peculiarities of Trypanosoma rangeli KP1(-) Strains Isolated from the Wild Rodent Phyllomys dasythrix (Santa Catarina, Brazil): Comparisons with T. rangeli KP1(+) strains and Trypanosoma lewisi (Kinetoplastea, Trypanosomatidae)

“…Recent molecular studies (Sincero et al 2015) point to a subdivision within the KP1(-) group, which corroborate the uniqueness of these isolates, besides others from wild Panstrongylus megistus from the same region (Vallejo et al 2002(Vallejo et al , 2015. This may reflect a process of speciation within T. rangeli, as advanced by some authors (Macedo et al 1993, closely associated to the vector lineages (Machado et al 2001;Vallejo et al 2002Vallejo et al , 2015Urrea et al 2005Urrea et al , 2011Maia-da-Silva et al 2007;Salazar-Antón et al 2009;Barreto-Santana et al 2015;Sincero et al 2015). At present, with so much available knowledge on T. rangeli genetic diversity, we question whether the KP1(-) group from southern Brazil could be a subspecies.…”

Los patrones electroforéticos de proteínas salivales permiten diferenciar los grupos transandino y cisandino de las especies de Rhodnius de Colombia

“…Recientemente, se ha reportado que las glándulas salivales de R. pictipes pueden ser infectadas por la cepa SC-58 de T. rangeli KP1(-). Por lo tanto, R. pictipes podría transmitir el genotipo KP1(-) de T. rangeli, exhibiendo así características biológicas similares a las evidenciadas en las especies del grupo transandino (34).…”

Revisiting Trypanosoma rangeli Transmission Involving Susceptible and Non-Susceptible Hosts

“…rangeli completes its development only in triatomines from the genus Rhodnius [ 15 ]. Biological and molecular studies suggest that these parasites and their vectors have coexisted over a long period, with diverging lineages that are associated with sympatric species of Rhodnius but without an apparent association with vertebrate host species [ 18 – 20 ]. This evolutionary relationship between T .…”