Interactions of murine leukemia virus (MuLV) with isolated lymphocytes. II. Infections of B and T cells with Friend virus complex indiffusion chambers and in vitro: effect of polyclonal mitogens.
The infection of isolated B and T cells by a murine leukemia virus (Friend) MuLV-F) was studied both in vitro and in vivo with an implanted diffusion chamber system. Lymphocytes were obtained from pools of normal spleen cells by filtration of the cell suspension through a nylon-wool column. The purity for both Ig positive and theta-positive cells varied between 85% and 90% in the B-cell and T-cell fractions; both lymphocyte fractions responded very well to stimulation with their respective specific polyclonal mitogens, bacterial lipopolysaccharide (LPS) and concanavalin A (Con A). Lymphocytes were infected by incubating pelleted cells in 2-6 x 10(4) FFU MuLV for 1 h at 4 degrees C and were then cultured for 5-10 days. Cells releasing infectious MuLV were enumerated as infectious centers (IC). IC were really detectable in the cultures of infected B-cells but none were found in the T-cell cultures. Addition of LPS to the culture medium increased the number of IC in B-cell fractions up to 1,000-fold. Furthermore, in T-cell cultures with LPS, IC also appeared in number which approximately correlated with the contaminating Ig+ cells of the T-cell fraction. In contrast, Con A had no consistent effect on the infection of either B or T cells. In the absence of MuLV-F, mitogenic stimulation alone did not elicit any endogenous IC. In subsequent experiments, purified lymphocytes were infected in diffusion chambers in vivo. The number of IC in infected B cells increased 1,000-fold as compared to infection in tissue culture. The peak of infection at 10 days was followed by a slight decline. Infected cells were also found in diffusion chambers containing T-cell fractions; these IC had very similar kinetics to those in B-cell-containing chambers, but their number was 10 times lower, suggesting that the infected cells were B cells, which comprised about 10% of the T-cell fraction. The virus-related antigens were detectable by immunofluorescence on the membrane of cells recovered from B-cell-bearing chambers but not on cells from T-cell-bearing chambers.
D000818:Animals; D000956:Antigens, Viral / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D002462:Cell Membrane / Q000276:immunology; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D005260:Female; D005622:Friend murine leukemia virus / Q000276:immunology*; D007942:Leukemia, Experimental / Q000276:immunology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D008934:Mitogens / Q000494:pharmacology*; D011135:Polysaccharides, Bacterial / Q000494:pharmacology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014779:Virus Replication / Q000187:drug effects*
D000956:Antigens, Viral; D008070:Lipopolysaccharides; D008934:Mitogens; D011135:Polysaccharides, Bacterial; D003208:Concanavalin A