rROP2 from Toxoplasma gondii as a potential vaccine against oocyst shedding in domestic cats.

Revista brasileira de parasitologia veterinaria = Brazilian journal of veterinary parasitology : Orgao Oficial do Colegio Brasileiro de Parasitologia Veterinaria

PubMedID: 28403374

Zulpo DL, Igarashi M, Sammi AS, Santos JR, Sasse JP, Cunha IA, Taroda A, Barros LD, Almeida JC, Jenkins MC, Navarro IT, Garcia JL. rROP2 from Toxoplasma gondii as a potential vaccine against oocyst shedding in domestic cats. Rev Bras Parasitol Vet. 2017;26(1):67-73.
THE AIM
of the present study was to evaluate oocyst shedding in cats immunized by nasal route with T.gondii proteins ROP2. Twelve short hair cats (Felis catus) were divided in three groups G1, G2 and G3 (n=4).

ANIMALS
from G1 received 100 µg of rROP2 proteins plus 20 µg of Quil-A, G2 received 100 µg of BSA plus 20 µg of Quil-A, and the G3 only saline solution (control group).All treatments were done by intranasal route at days 0, 21, 42, and 63. The challenge was performed in all groups on day 70 with ? 800 tissue cysts of ME-49 strain by oral route.

ANIMALS
from G1 shed less oocysts (86.7%) than control groups. ELISA was used to detect anti-rROP2 IgG and IgA, however, there were no correlation between number of oocyst shedding by either IgG or IgA antibody levels. In the present work, in spite of lesser oocysts production in immunized group than control groups, it was not possible to associate the use of rROP2 via nostrils with protection against oocyst shedding. For the future, the use of either other recombinant proteins or DNA vaccine, in combination with rROP2 could be tested to try improving the efficacy of this kind of vaccine.