Producción y caracterización de anticuerpos monoclonales contra la fiebre aftosa

Se describen los anticuerpos monoclonales (AcMs) producidos contra los virus de la fiebre aftosa tipo O, A y C. Para la caracterización preliminar se utilizaron las pruebas de virus-neutralización y seroprotección, y para la reacción de los AcMs, la prueba EITB con la proteína desnaturalizada del virus. Algunos AcMs que no neutralizaron la infección del virus en cultivos de tejidos se mostraron capaces de neutralizarla en ratones lactantes. Los AcMs designados 7EE6 y 7jA1, originarios del virus C3 Indaial, mostraron reacción cruzada con los virus heterólogos O1 Campos y A24 Cruzeiro de la fiebre aftosa.

Monoclonal antibodies (MAbs) produced against foot-and-mouth disease virus (FMDV) types O, A, and C are described. The preliminary characterization id discussed in terms of virus neutralization and mouse protection test results and the reactivity of MAbs in enzyme-linked immnoelectrotransfer blot assays with the denatured protein of the virus. Some MAbs which did not neutralize virus infectivity in tissue culture were able to neutralize virus infectivity in suckling mice. The MAbs designated as 7EE6 and 7JA1 which originated from C, Indaial virus cross-reacted with heterologus FMDV O(1) Campos and A(24) Cruzeiro viruses.

Extensive antigenic heterogeneity of foot-and-mouth disease virus of serotype C.

The antigenic behavior of 46 field isolates of foot-and-mouth disease virus (FMDV) of serotype C has been studied with a panel of 24 monoclonal antibodies (MAbs) prepared against FMDV C1 or FMDV C3 Indaial. Reactivities were assayed by immunodot, immunoelectrotransfer blot, and neutralization of infectivity. The epitopes recognized by the 10 nonneutralizing MAbs are conserved in all isolates analyzed. In contrast, extreme antigenic heterogeneity is documented with regard to reactivity with 14 MAbs that, on this basis, define at least 12 epitopes involved in neutralization of FMDV of serotype C. The 31 isolates from South America were divided into 17 distinct antigenic groups and the 15 isolates from Europe into 7 groups. Lack of correspondence between antigenic composition and the origin--date and place of isolation--of the viruses was noted in several instances. Antigenic heterogeneity is shown among epidemiologically closely related FMDVs. In most--but not all--cases tested, a good correlation was found between binding of a neutralizing MAb to virions and its ability to neutralize infectivity. It is concluded that variation of epitopes involved in neutralization of FMDV is extensive among subtypes of serotype C and also among individual isolates of one subtype.