Avaliação de testes sorológicos para leishmaniose visceral canina utilizando coleta de amostra sanguíneas em papel de filtro
xviVisceral Leishmaniasis comes presenting important changes in its standard oftransmission, with gradual urbanization and geographic expansion, attacking undamagedconsidered regions previously. The control of the illness if has shown difficult andlaborious, e the experience acquired in the last decades discloses the necessity of if usingthe measures of control of integrated form. Enclosed it enters the strategies praised for thepublic agencies, the elimination of the canine reservoirs constitutes an important actionthat, to be executed, it demands a correct identification of the dogs with infection. Othermeasures, as the vaccination of the dogs, they have been also used. With the introduction inthe market of a vaccine against the Canine Visceral Leishmaniasis (Leishmune®), capableto cause the development of high levels of IgG antibodies, the use of new serologicalmarkers becomes necessary. Moreover, for the serodiagnosis of the infection forLeishmania chagasi, the use of blood desiccated in filter paper (SDPF) is desirable,therefore it presents advantages on the use of serum gotten for venopuncture, mainly withrelation to the involved costs with logistic and the easinesses for use in field conditions.Thus, in this work, one searched to validate, in samples of serum and SDPF, one hastested of indirect fluorescence antibody (IFA), developed for the Bio-Manguinhos, e twoenzyme linked immunosorbent assay (ELISA), being one of them also developed by theBio-Manguinhos and the other developed in accordance with the described technique forVoller (1976) with modifications, using dissolvable antigen gotten from promastigotas of L.major-like. The reproducibility of the levels of antibodies IgG, IgG1 and IgG2 was alsoevaluated, for these serological reactions, to long of the passed time after the collection.Moreover, it was determined capacity of the antibodies IgG1 and IgG2 of if constituting inmarkers of active infection of L. chagasi and their behavior in samples of SDPF.The samples of serum and eluates of SDPF gotten of 161 dogs - being 31 negatives,10 with Trypanosoma cruzi infection, 42 asymptomatic, 45 oligosymptomatic and 33polisymptomatic for L. chagasi infection - they had been assayed in duplicate in the 1º dayafter collection (D.A.C.), being that in 15º, 30º and 60º D.A.C. they had been assayedaliquot of samples of eluates of SDPF and compared with the results gotten with the serumin 1º D.A.C. The validity of the reactions, in serum and eluates, it was surveyed through theindices of the co-positivity (icp), co-negativity (icn), agreement of Youden (j) and thepreditivos values positive (vpp) and negative (vpn), using it reaction of IFA in serum asreference, a time that this reaction demonstrated allegiance in identifying the truily positiveand negative animals correctly. The IFA, ELISA (Bio-Manguinhos), ELISA IgG (Ag. L.major-like) and ELISA IgG2 (Ag. L. major-like), in samples of serum and eluates, if theyhad shown valid for the serodiagnosis of the LVC. The crossed distribution of the resultsgotten with serum and eluates, for each evaluated reaction, it disclosed and goodagreements for the IFI reactions excellent, ELISA (Bio-Manguinhos), ELISA IgG (Ag. L.major-like) and ELISA IgG2 (Ag. L. major-like). The analysis of the reproducibility of thereactions in SDPF, stored 4ºC with silica-gel, in function of the time, it demonstrated thatlevels of specific antibodies IgG, gifts in the samples of SDPF, they had been remainedsteady for up to 30 D.A.C. for the reaction of IFI and up to 60 D.A.C. for the reactions ofELISA (Bio-Manguinhos) and ELISA (Ag. L. major-like). The specific antibodies of thesubclasses IgG1 and IgG2, gifts in the samples of SDPF, also they had kept its steady levelsfor up to 60 D.A.C. for the reaction of ELISA (Ag. L. major-like). It was not possible toestablish a correlation enters the levels of the antibodies IgG, IgG1 and IgG2 with theclinical classification of the dogs with L. chagasi infection.
Advisor:Maria Terezinha Bahia; George Luiz Lins Machado Coelho; Aluízio Rosa Prata
School:Universidade Federal de Ouro Prêto
Source Type:Master's Thesis
Date of Publication:04/05/2005