Complement-dependent neutralization of transmissible gastroenteritis virus by monoclonal antibodies.

Monoclonal antibodies (MAb) to each of the 3 major structural proteins of transmissible gastroenteritis virus (TGEV) of swine were compared as to their virus neutralizing activity in the presence or absence of guinea pig complement. MAbs to the peplomer protein had neutralizing activity for TGEV with or without complement and the titers were similar in either case. MAbs to the matrix protein had neutralizing activity for TGEV only in the presence of complement. Antibodies to the nucleocapsid protein were without neutralizing activity with or without complement. High concentrations of guinea pig complement, but not swine complement, had neutralizing activity for TGEV even in the absence of any known TGEV antibodies.