title: An assessment of the effects of ectopic gp91phox expression in XCGD iPSC-derived neutrophils.
abstract: For the treatment of monogenetic hematological disorders, restoration of transgene expression in affected cell populations is generally considered to have beneficial effects. However, X-linked chronic granulomatous disease (XCGD) is unique since the appearance of functional neutrophils in the peripheral blood following hematopoietic stem cell gene therapy is transient only. One contributing factor could be the occurrence of detrimental effects secondary to ectopic gp91phox expression in neutrophils, which has not been formally demonstrated previously. This study uses iPSCs to model XCGD, which allows the process of differentiation to be studied intensely in vitro. Alpharetroviral vectors carrying a ubiquitous promoter were used to drive the "ectopic" expression of codon optimized gp91phox cDNA. In the mature fraction of neutrophils differentiated from transduced XCGD-iPSCs, cellular recovery in terms of gp91phox expression and reactive oxygen species production was abruptly lost before cells had fully differentiated. Most critically, ectopic gp91phox expression could be identified clearly in the developing fraction of the transduced groups, which appeared to correspond with reduced cell viability. It is possible that this impedes further differentiation of developing neutrophils. Therefore, affording cellular protection from the detrimental effects of ectopic gp91phox expression may improve XCGD clinical outcomes.
authors.affiliation: Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo , Tokyo, Japan ; Division of Stem Cell Processing/Stem Cell Bank, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo , Tokyo, Japan.
authors.forename: Huan-Ting
authors.initials: HT
authors.lastname: Lin
authors.affiliation: Japan Science Technology Agency, Exploratory Research for Advanced Technology Nakauchi Stem Cell and Organ Regeneration Project , Tokyo, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Masaki
authors.affiliation: Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo , Tokyo, Japan ; Japan Science Technology Agency, Exploratory Research for Advanced Technology Nakauchi Stem Cell and Organ Regeneration Project , Tokyo, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yamaguchi
authors.affiliation: Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University , Kanazawa, Japan.
authors.forename: Taizo
authors.initials: T
authors.lastname: Wada
authors.affiliation: Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University , Kanazawa, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Yachie
authors.affiliation: Research Center for Stem Cell Engineering, National Institute of Advanced, Industrial Science and Technology , Tsukuba, Japan ; Laboratory of Gene Regulation, Faculty of Medicine, University of Tsukuba , Tsukuba, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Nishimura
authors.affiliation: Research Center for Stem Cell Engineering, National Institute of Advanced, Industrial Science and Technology , Tsukuba, Japan.
authors.forename: Manami
authors.initials: M
authors.lastname: Ohtaka
authors.affiliation: Research Center for Stem Cell Engineering, National Institute of Advanced, Industrial Science and Technology , Tsukuba, Japan.
authors.forename: Mahito
authors.initials: M
authors.lastname: Nakanishi
authors.affiliation: Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo , Tokyo, Japan ; Japan Science Technology Agency, Exploratory Research for Advanced Technology Nakauchi Stem Cell and Organ Regeneration Project , Tokyo, Japan.
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Nakauchi
authors.affiliation: Division of Stem Cell Therapy, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo , Tokyo, Japan ; Division of Stem Cell Processing/Stem Cell Bank, Center for Stem Cell Biology and Regenerative Medicine, Institute of Medical Science, University of Tokyo , Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Otsu