title: Differential expression of endogenous virus glycoprotein in fibroblasts and sera of some adult chickens.
abstract: A rapid and convenient assay for the expression of endogenous retrovirus glycoprotein in adult chickens has been developed based on the enzyme-linked immunosorbent assay (ELISA) principle. This method has been standardized using the conventional chick helper factor test. In the course of establishing this method with a large number of specific pathogen-free (VALO) chickens, an interesting diversity became apparent; about 20% of the birds which, according to chick helper factor tests performed with feather follicle fibroblast cultures were negative for endogenous virus glycoprotein expression, exhibited relatively high titres of reactive glycoprotein in serum. However, in no case was a chick helper factor-positive animal negative in serological tests. The possibility of endogenous virus antigen expression which either cannot be detected in fibroblasts, or is incapable of functioning in the chick helper factor complementation, is discussed.
mesh_terms: D000818:Animals; D001358:Avian Sarcoma Viruses / Q000254:growth & development; D001681:Biological Assay; D002478:Cells, Cultured; D002645:Chickens / Q000097:blood / Q000378:metabolism* / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000032:analysis*; D006023:Glycoproteins / Q000032:analysis*; D012190:Retroviridae / Q000032:analysis*; D014764:Viral Proteins / Q000032:analysis*
chemical_list: D006023:Glycoproteins; D014764:Viral Proteins