title: Quantitative correlation between transcriptional levels of ER chaperone, peroximal protein and FVIII productivity in human Hek-293 cell line.
abstract: Hek-293 cell line presents good production platform for recombinant therapeutic proteins, however little is known about the components that contribute to the cellular control of recombinant protein production. In this study, we generated a Hek-293 producing recombinant factor VIII (FVIII) and we evaluated the immunoglobulin-binding protein (BiP) and phytanoil-CoA α-hydroxylase (PAHX) expression levels which are known for diminishing FVIII production. Our analyses showed that the recombinant cell population expresses 3.1 ± 1.4 fold of BIP mRNA (P = 0.0054) and 97.8 ± 0.5 fold of PAHX mRNA (P = 0.0016) compared to nontransduced cells. The amount of these proteins was inversely correlated to the secreted FVIII. In conclusion, BIP and PAHX expression are augmented in human cells producing FVIII and they antagonize the amount of therapeutic factor VIII in the cell culture.
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil ; Faculty of Pharmaceutical Sciences in Ribeirão Preto-FCFRP, University of São Paulo-USP, São Paulo, Brazil ; Hemocentro de Ribeirão Preto, National Institute of Science and Technology in Stem Cell and Cell Therapy, Avenida Tenente Catão Roxo, 2501 - Ribeirão Preto, São Paulo, 14051-140 Brazil.
authors.forename: Evandra Strazza
authors.initials: ES
authors.lastname: Rodrigues
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil.
authors.forename: Virgínia
authors.initials: V
authors.lastname: Picanço-Castro
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil.
authors.forename: Marta Regina
authors.initials: MR
authors.lastname: Espanhol
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil.
authors.forename: Luiz Alberto Martins
authors.initials: LA
authors.lastname: de Andrade
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil.
authors.forename: Patricia Vianna Bonini
authors.initials: PV
authors.lastname: Palma
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil ; Faculty of Pharmaceutical Sciences in Ribeirão Preto-FCFRP, University of São Paulo-USP, São Paulo, Brazil ; Hemocentro de Ribeirão Preto, National Institute of Science and Technology in Stem Cell and Cell Therapy, Avenida Tenente Catão Roxo, 2501 - Ribeirão Preto, São Paulo, 14051-140 Brazil.
authors.forename: Simone
authors.initials: S
authors.lastname: Kashima
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil ; Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil.
authors.forename: Aparecida Maria
authors.initials: AM
authors.lastname: Fontes
authors.affiliation: Hemotherapy Center of Ribeirão Preto , Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil ; Faculty of Medicine in Ribeirão Preto-FMRP, University of São Paulo-USP, São Paulo, Brazil ; Hemocentro de Ribeirão Preto, National Institute of Science and Technology in Stem Cell and Cell Therapy, Avenida Tenente Catão Roxo, 2501 - Ribeirão Preto, São Paulo, 14051-140 Brazil.
authors.forename: Dimas Tadeu
authors.initials: DT
authors.lastname: Covas
keywords: ER BIP chaperone; Factor VIII; Hemophilia A; PAHX gene expression and Recombinant Factor VIII∆B