Protective activity against oocyst shedding in cats vaccinated with crude rhoptry proteins of the Toxoplasma gondii by the intranasal route.
This study evaluated a vaccine made from crude rhoptry proteins of Toxoplasma gondii with Quil-A, which was administered to cats by the intranasal route. Eleven short-hair domestic cats were divided into four groups: G1 (n=3) received three doses (200 microg/dose) of the rhoptry vaccine with Quil-A (20 microg); G2 (n=3) received PBS with Quil-A (20 microg); G3 (n=3) and G4 (n=2) received only PBS. Treatments were administered at days 0, 21, and 42 by the intranasal route. Challenge was done to G1, G2, and G3 animals with 600 cysts of the VEG strain on day 51 (challenge day); G4 animals were unchallenged. The anti-T. gondii IgG and IgA antibody levels from sera were measured by indirect enzyme-linked immunosorbent assay (ELISA). At challenge, two animals from G1 revealed antibody levels for both IgG and IgA; oocysts were not detected in feces of these two cats. There were no differences in hematological values between groups throughout the experiment (p>0.10). Preventable fractions were 67% in G1 and 0% in G2 and G3. Comparatively, G1 animals shed 89.3% and 90.8% less oocysts than G3 and G4, respectively. Two out of three cats were protected against T. gondii oocyst shedding when the rhoptry vaccine was administered by the intranasal route. This is the first study using crude rhoptry proteins as vaccine by the intranasal route in cats to evaluate protection against oocysts shedding.
Garcia
João Luis
JL
Protozoology laboratory, Departamento de Medicina Veterinária Preventiva, Universidade Estadual de Londrina, Postal Box 6001, 86050-970 Londrina, PR, Brazil. jlgarcia@uel.br
Navarro
Italmar Teodorico
IT
Biazzono
Luciane
L
Freire
Roberta Lemos
RL
da Silva Guimarães Junior
José
J
Cryssafidis
Andréas L
AL
Bugni
Felipe Monteiro
FM
da Cunha
Ivo Alexandre Leme
IA
Hamada
Fernando N
FN
Dias
Renata Cristina Ferreira
RC
D000281:Administration, Intranasal; D000818:Animals; D002371:Cat Diseases / Q000517:prevention & control*; D002415:Cats; D005243:Feces / Q000469:parasitology; D005260:Female; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008565:Membrane Proteins / Q000276:immunology; D033661:Oocysts; D015800:Protozoan Proteins / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D013997:Time Factors; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000517:prevention & control*
D007070:Immunoglobulin A; D007074:Immunoglobulin G; D008565:Membrane Proteins; D015800:Protozoan Proteins; D016052:Protozoan Vaccines