title: A human papillomavirus 8 E7 protein produced in plants is able to trigger the mouse immune system and delay the development of skin lesions.
abstract: We investigated the potential of Nicotiana benthamiana to express the E7 protein of human papillomavirus 8 (HPV-8), a paradigm genotype among cutaneous HPVs. The protein, modified in its putative pRb-binding domain (E7(QGD)), was transiently expressed in leaves following infiltration with agrobacteria carrying either a binary vector combined with silencing suppressor constructs or replicating tobacco mosaic virus (TMV)-based vectors with different targeting signals. HPV-8 E7(QGD) yields ranged from 250 ng to 4.6 mg per gram of fresh leaf tissue. The highest yields were obtained with TMV-based vectors targeting the antigen to the apoplast. HPV8-CER (H2(q)) mice transformed with the complete early region of HPV-8 showed a delay in the onset of skin papillomatous lesions and produced E7-specific immunoglobulins G when inoculated subcutaneously with leaf extracts expressing E7(QGD). Furthermore, we demonstrated that the plant-made HPV-8 E7(QGD) induced a specific cytotoxic response in C57BL/6 (H2(b)) mice.
authors.affiliation: Istituto di Virologia Vegetale, Consiglio Nazionale delle Ricerche, Strada delle Cacce 73, Turin, Italy. e.noris@ivv.cnr.it
authors.forename: Emanuela
authors.initials: E
authors.lastname: Noris
authors.forename: Alice
authors.initials: A
authors.lastname: Poli
authors.forename: Rodica
authors.initials: R
authors.lastname: Cojoca
authors.forename: Massimo
authors.initials: M
authors.lastname: Rittà
authors.forename: Federica
authors.initials: F
authors.lastname: Cavallo
authors.forename: Stany
authors.initials: S
authors.lastname: Vaglio
authors.forename: Slavica
authors.initials: S
authors.lastname: Matic
authors.forename: Santo
authors.initials: S
authors.lastname: Landolfo
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D003602:Cytotoxicity, Immunologic; D004195:Disease Models, Animal; D007074:Immunoglobulin G / Q000097:blood; D007279:Injections, Subcutaneous; D051379:Mice; D008810:Mice, Inbred C57BL; D009856:Oncogene Proteins, Viral / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D010212:Papilloma / Q000276:immunology / Q000517:prevention & control*; D053918:Papillomavirus Vaccines / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012867:Skin; D012878:Skin Neoplasms / Q000276:immunology / Q000517:prevention & control*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D009856:Oncogene Proteins, Viral; D053918:Papillomavirus Vaccines; D011994:Recombinant Proteins; C066076:oncogene protein E7, Human papillomavirus type 8