Viral Antigen, Virus Particles, and Infectivity of Tissues From Chickens With Marek's Disease

Summary

The same tissues from S-line chickens infected with the JM strain of Marek's disease virus were examined by the fluorescent antibody (FA) and agar-gel precipitin (AGP) tests and by electron microscopy (EM). In vitro virus assays of cellular and cell-free materials from some tissues were done. All samples of feather follicle epithelium (FFE) were positive for antigen detectable by FA and AGP, contained large numbers of both naked and enveloped herpesvirus particles, and were the source of infectious, cell-free virus. The bursa of Fabricius, kidney, leukotic gonad, and nerve plexuses also contained FA-detectable antigen but not so consistently or extensively as did the FFE. All these tissues, except kidney, were found positive by the AGP test and were determined by EM to be infected, but nearly all virus particles were naked and intranuclear. In vitro virus assays showed infectivity to be cell-associated.