title: Epstein-Barr virus LMP2A enhances B-cell responses in vivo and in vitro.
abstract: Epstein-Barr virus (EBV) establishes latent infections in a significant percentage of the population. Latent membrane protein 2A (LMP2A) is an EBV protein expressed during latency that inhibits B-cell receptor signaling in lymphoblastoid cell lines. In the present study, we have utilized a transgenic mouse system in which LMP2A is expressed in B cells that are specific for hen egg lysozyme (E/HEL-Tg). To determine if LMP2A allows B cells to respond to antigen, E/HEL-Tg mice were immunized with hen egg lysozyme. E/HEL-Tg mice produced antibody in response to antigen, indicating that LMP2A allows B cells to respond to antigen. In addition, E/HEL-Tg mice produced more antibody and an increased percentage of plasma cells after immunization compared to HEL-Tg littermates, suggesting that LMP2A increased the antibody response in vivo. Finally, in vitro studies determined that LMP2A acts directly on the B cell to increase antibody production by augmenting the expansion and survival of the activated B cells, as well as increasing the percentage of plasma cells generated. Taken together, these data suggest that LMP2A enhances, not diminishes, B-cell-specific antibody responses in vivo and in vitro in the E/HEL-Tg system.
authors.affiliation: Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Ward 6-231, 303 E. Chicago Ave., Chicago, IL 60611, USA.
authors.forename: Michelle
authors.initials: M
authors.lastname: Swanson-Mungerson
authors.forename: Rebecca
authors.initials: R
authors.lastname: Bultema
authors.forename: Richard
authors.initials: R
authors.lastname: Longnecker
mesh_terms: D000818:Animals; D000917:Antibody Formation / Q000235:genetics / Q000276:immunology*; D000941:Antigens / Q000276:immunology; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000235:genetics / Q000276:immunology; D020031:Epstein-Barr Virus Infections / Q000235:genetics / Q000276:immunology; D005260:Female; D008213:Lymphocyte Activation / Q000235:genetics / Q000276:immunology*; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009113:Muramidase / Q000235:genetics / Q000276:immunology; D010950:Plasma Cells / Q000276:immunology*; D019076:Transgenes / Q000235:genetics / Q000276:immunology; D014763:Viral Matrix Proteins / Q000235:genetics / Q000276:immunology*
chemical_list: D000941:Antigens; C037662:EBV-associated membrane antigen, Epstein-Barr virus; D014763:Viral Matrix Proteins; D009113:Muramidase