Differences between early and late membrane antigens on cultured cells infected with herpesvirus of turkeys.

The synthesis of membrane antigen (MA) and intracellular antigen (IA) in arginine-deficient cultures infected with herpesvirus of turkeys (HVT) and their antigenic relationships were examined. By the indirect immunofluorescence test, two kinds of MA were detected using anti-HVT chicken serum [early appearing MA (EMA) and late appearing MA (LMA)], but few IA positive cells were detected. Absorption of the serum by MA positive cells resulted in reduction of reactivity to MA but not to IA. Differential absorption of the serum by EMA positive cells and LMA positive cells considerably reduced their reactivities to homologous cells but not to heterologous cells which were used in the absorptions. Both absorbed sera had similar IA reactivity when compared with the reactivity of un-absorbed serum, but the serum absorbed by LMA positive cells decreased its neutralising titre. These results provide evidence that (1) MA and IA are antigenically different from each other; (2) EMA is different from LMA; and (3) antibody against LMA is closely related to antibody for neutralisation of HVT.