A monoclonal antibody to ICP4 of MDV recognizing ICP3 of serotype 1 and 3 MDV strains

Monoclonal antibodies (MAbs) were prepared against ICP4 of Marek's disease virus (MDV). Mice were inoculated with ICP4 obtained from High-Five insect cells infected with a recombinant baculovirus expressing ICP4. MAbs were se lected by enzyme-linked immunosorbent assay (ELISA) using MDV-infected and control chick kidney cells as antigens. One of the MAbs, 5H8, recognized an epitope toward the carboxyl terminus of ICP4 based on staining of reticulo endotheliosis virus-transformed cells transfected with full-length and trun cated ICP4 constructs. This MAb recognized ICP4 in chicken embryo fibroblas ts (CEFs) infected with MDV strains JM16 and HVT but not with SB-1 strain. Using Western blot analysis a protein of 155 kDa was detected in CEFs infec ted with JM16 and HVT strains.