title: Verification of the Inactivation of Melanocytic Nevus in vitro Using a Newly Developed Portable High Hydrostatic Pressure Device.
abstract: High hydrostatic pressure (HHP) technology is a physical method for inactivating tissue. We reported that nevus specimens were inactivated after HHP at 200 MPa and that the inactivated nevus could be used as autologous dermis for covering skin defects. In this study, we verified the inactivation of nevus specimens using a newly developed portable HHP device which will be used in a clinical trial. Nevus tissue specimens were obtained from 5 patients (mean age 7.2 years, range 1-19). We cultured fibroblasts and nevus cells from the tissue specimens and then evaluated their inactivation after HHP at 200 MPa by confirming the attachment of the suspensions and by the live/dead staining of the suspensions, through the dissociation of the cells on chamber slides and by the live/dead staining of the remaining cells. The cells were also quantitatively evaluated by WST-8 assay. We then confirmed the inactivation of the nevus specimens after HHP using explant culture. Our results indicated that fibroblasts and nevus cells were inactivated after HHP at 200 MPa, with the exception of a small percentage of green-colored cells, which reflected the remaining activity of the cellular esterases after HHP. No cells migrated from the nevus specimens after HHP at 200 MPa. We verified the inactivation of fibroblasts and nevus cells cultured from nevus specimens, and in the nevus samples themselves after pressurization at 200 MPa using this device. This device could be used in clinical trials for giant congenital melanocytic nevi and may thus become useful in various medical fields.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Morimoto
authors.forename: Chizuru
authors.initials: C
authors.lastname: Jinno
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mahara
authors.forename: Natsuko
authors.initials: N
authors.lastname: Kakudo
authors.forename: Toshia
authors.initials: T
authors.lastname: Fujisato
authors.forename: Kenji
authors.initials: K
authors.lastname: Kusumoto
authors.forename: Shigehiko
authors.initials: S
authors.lastname: Suzuki
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Yamaoka
mesh_terms: D000293:Adolescent; D002470:Cell Survival; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D005347:Fibroblasts / Q000166:cytology / Q000473:pathology*; D006801:Humans; D006874:Hydrostatic Pressure; D007223:Infant; D009508:Nevus, Pigmented / Q000473:pathology* / Q000628:therapy*; D012867:Skin / Q000473:pathology*; D012878:Skin Neoplasms / Q000473:pathology* / Q000628:therapy*; D055815:Young Adult