title: A 10 patient case report on the impact of plasmapheresis upon neutralizing factors against adeno-associated virus (AAV) types 1, 2, 6, and 8.
abstract: Adeno-associated viruses (AAV) are small, nonenveloped single-stranded DNA viruses which require helper viruses to facilitate efficient replication. These recombinant viruses are some of the most promising candidates for therapeutic gene transfer to treat many genetic and acquired diseases. Nevertheless, the presence of humoral responses to the wild-type AAV common among humans is one of the limitations of in vivo transduction efficacy in humans using cognate recombinant vector. In this study, based on the serum samples that we were able to collect from various clinical situations, we studied the impact of one to five plasmapheresis (PP), at 1-5 day intervals on neutralizing factor (NAF) titers specific for AAV types 1, 2, 6, and 8 in seropositive patients with diverse pathologies and immunosuppressor treatments. We show that frequent sessions of PP result in drastic reduction of NAF specific for AAV1, 2, 6, and 8 to undetectable levels or titers <1:5, mainly when initial titers, i.e., before the first PP were ≤1:20. Altogether, these results show that the use of PP and its possible association with pharmacological immunosuppressive treatments may help to design optimal management of seropositive patients for AAV gene therapy treatments.
authors.affiliation: Laboratoire d'Immunologie, R&D, GENETHON, Cedex, France.
authors.forename: Virginie
authors.initials: V
authors.lastname: Monteilhet
authors.forename: Samir
authors.initials: S
authors.lastname: Saheb
authors.forename: Sylvie
authors.initials: S
authors.lastname: Boutin
authors.forename: Christian
authors.initials: C
authors.lastname: Leborgne
authors.forename: Philippe
authors.initials: P
authors.lastname: Veron
authors.forename: Marie-Françoise
authors.initials: MF
authors.lastname: Montus
authors.forename: Philippe
authors.initials: P
authors.lastname: Moullier
authors.forename: Olivier
authors.initials: O
authors.lastname: Benveniste
authors.forename: Carole
authors.initials: C
authors.lastname: Masurier
mesh_terms: D000328:Adult; D057134:Antibodies, Neutralizing / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood*; D000229:Dependovirus / Q000235:genetics / Q000276:immunology*; D005260:Female; D005822:Genetic Vectors / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D010956:Plasmapheresis; D055815:Young Adult
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D007074:Immunoglobulin G