Trypanosoma rhipicephalis sp. nov. (Protozoa: Kinetoplastida) isolated from Rhipicephalus microplus (Acari: Ixodidae) ticks in Rio de Janeiro, Brazil

Abstract

Parasites of the genusTrypanosomaare unicellular flagellated microorganisms of theTrypanosomatidae. This study describes an isolate of the genusTrypanosomanaturally infectingRhipicephalus microplusticks, characterized through molecular, morphological and biological analysis. Trypanosome cultures, designated strain P1RJ, were obtained by isolation fromR. microplushaemolymph in cultures of the tick cell line IDE8. After isolation, strain P1RJ grew well axenically in L15B medium at temperatures of 30, 32 and 34 °C. The new trypanosome remained stable in axenic culture over 14 passages in L15B at 30 °C and was successfully cryopreserved and resuscitated. Morphometric analysis was performed on randomly selected developmental forms. 18S rRNA and 24Sα rDNA sequence analyses confirmed that strain P1RJ is a new species of the genusTrypanosoma. The nucleotide sequences described were submitted to Genbank. Pathogenicity, involvement in vertebrate hosts, epidemiology, developmental cycle and transmission mechanisms of strain P1RJ are still unknown. Therefore, more studies will be necessary to determine life cycle aspects of this trypanosome, for which we propose the nameTrypanosoma rhipicephalissp. nov.

Trypanosoma amblyommi sp. nov. (Protozoa: Kinetoplastida) isolated from Amblyomma brasiliense (Acari: Ixodidae) ticks in Rio de Janeiro, Brazil

“…Trypanosoma amblyommi was propagated in L15B medium, which is used for culturing tick cells (Munderloh and Kurtti., 1989) and only at temperatures between 30 and 34°C. Similar behaviour was observed for the recently described T. rhipicephalis, also isolated into IDE8 cell culture from ticks in the state of Rio de Janeiro (Marotta et al 2018). In the present study, although no adverse effect of the initial crushed tick suspension on the IDE8 cells was detected, subsequent co-cultivation of T. amblyommi with tick cells resulted in detachment and death of the latter.…”

“…We recently reported isolation of a novel trypanosome, Trypanosoma rhipicephalis sp. nov, from Brazilian Rhipicephalus microplus ticks removed from cattle (Marotta et al 2018).…”

Isolation and partial characterisation of a novel Trypanosoma from the tick Ixodes ricinus

“…Morphometric analysis was performed to compare the isolate, designated Trypanosoma sp. Bratislava1, with other tick-associated Trypanosoma species for which equivalent data for culture-derived epimastigotes was available, namely Trypanosoma rhipicephalis isolated from Rhipicephalus microplus ( Marotta et al, 2018a ) and Trypanosoma amblyommi isolated from Amblyomma brasiliense ( Marotta et al, 2018b ) ( Table 1 ). For all three trypanosomes, the mean values for all measured parameters except the distance from the middle of the nucleus to the anterior end (NA) and the length of free flagellum (FF) fell within the same range.…”

“…Bratislava1 40.66 ± 4.96 (30.57–50.71) 10.71 ± 2.96 (5.59–20.34) 2.14 ± 1.61 (1.00–9.18) 8.30 ± 2.30 (2.17–12.34) 21.34 ± 3.02 (14.26–27.98) 10.55 ± 2.10 (7.27–16.00) 2.58 ± 0.63 (1.52–4.36) 1.11 ± 0.45 (0.63–2.96) Trypanosoma rhipicephalis 32.44 ± 4.13 13.29 ± 2.57 1.74 ± 1.60 13.34 ± 2.97 6.90 ± 2.67 11.90 ± 2.17 1.90 ± 0.43 1.21 ± 0.36 Trypanosoma amblyommi 41.72 ± 8.85 15.47 ± 4.26 1.18 ± 0.38 15.61 ± 5.12 10.74 ± 2.90 14.59 ± 4.09 1.84 ± 0.37 1.23 ± 0.39 Morphometric data (μm) for Trypanosoma sp. Bratislava1 epimastigotes (n = 23) were compared to published data from other T rypanosoma species isolated from ticks, Trypanosoma rhipicephalis ( Marotta et al, 2018a ) and Trypanosoma amblyommi ( Marotta et al, 2018b ). Parameters measured were total length (TL); posterior end to kinetoplast (PK); kinetoplast to middle of nucleus (KN); middle of nucleus to anterior end (NA); free flagellum (FF); posterior end to middle of nucleus (PN); nucleus diameter (NL); kinetoplast length (K).…”

“… Morphometric data (μm) for Trypanosoma sp. Bratislava1 epimastigotes (n = 23) were compared to published data from other T rypanosoma species isolated from ticks, Trypanosoma rhipicephalis ( Marotta et al, 2018a ) and Trypanosoma amblyommi ( Marotta et al, 2018b ). Parameters measured were total length (TL); posterior end to kinetoplast (PK); kinetoplast to middle of nucleus (KN); middle of nucleus to anterior end (NA); free flagellum (FF); posterior end to middle of nucleus (PN); nucleus diameter (NL); kinetoplast length (K).…”