Immunohistochemical expression of mammary tumor virus antigens in mammary glands of virgin mice, in relation to Mtv genes.
MTV antigens in the resting mammary glands of GRS/A, SHN, C3H, and Balb/c virgin mice were detected by immunoperoxidase techniques using antiserum against MTV whole virion, gp 52 or p 25 to differentiate the expression between endogenous and exogenous MTV. Balb/c mice were crossed to infect MTV into each reciprocal hybrid or fosternursed inbred. Immunohistochemical stainings of gp 52 in the formol-fixed sections were almost the same as those of the whole MTV virion, and the results on various cases were as follows: In the mice with endogenous GR-MTV, positivity was first observed at the age of 14 days, while the first expression of exogenous GR-MTV was delayed to the age of 140 days. The mice with endogenous and/or exogenous SHN-MTV showed the first antigen appearance at the age of 65 days, and those with exogenous C3H-MTV did at the age of 80 days. The virgins with only endogenous C3H-MTV came to express the antigen after the age of 200 days. Staining of p 25 in Carnoy-fixed sections of MTV-positive mammary glands was found in the supranuclear cytoplasm and apical surface of the glandular cells and the lumen, all of which are the site of A and B particles. By means of preembedding method for gp 52, the reaction products were ultrastructurally detected not only on the MTV-budding apical surface, together with the intraluminal B particles, but also on the MTV-free apical cell membrane of the glandular cells in the mammary gland of the GR virgins.
D000818:Animals; D000956:Antigens, Viral / Q000032:analysis / Q000235:genetics*; D003433:Crosses, Genetic; D005260:Female; D005796:Genes; D005814:Genes, Viral; D005838:Genotype; D007124:Immunoenzyme Techniques; D008297:Male; D008321:Mammary Glands, Animal / Q000382:microbiology* / Q000648:ultrastructure; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics*; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D013045:Species Specificity
D000956:Antigens, Viral