title: Adipose Tissue is A Better Source of Immature Non-Hematopoietic Cells than Bone Marrow.
abstract: Adipose tissue (AT) is an alternative source of the adult stem cells that can also be harvested from bone marrow (BM). Cultured AT-derived stem cells (ASCs) have been well characterized by many groups. However, non-cultured ASCs remain to be characterized. Hoechst 33342 dye efflux is a characteristic that is common to stem cells, as well as chemotherapy-resistant cancer cells. Thus, we compared the Hoechst 33342-stained side population (SP) cells in murine adipose-tissue (AT-SP cells) to the SP cells from murine bone marrow (BM-SP cells). The AT-SP cells were detected much more frequently in the 22 AT samples that were tested (0.42∼6.00%, mean 2.57%) than the BM-SP cells were detected in the 6 BM samples (0.02∼0.36%, mean 0.12%). After Hoechst staining, SP cells were analyzed by fluorescence-activated cell sorting (FACS) and electron micrograms. FACS analysis revealed that the AT-SP cells were CD44-, CD45-, CD45R+, Sca-1± and c-kit-, while the BM-SP cells were CD44-, CD45±, CD45R-, Sca-1+ and c-kit+. This indicates that the AT-SP cells differ phenotypically from the BM-SP cells. Electron microscopic analysis revealed that the AT-SP cells are small cells with a diameter of about 5 um. Some of the BM-SP cells had granules, similar to eosinophils or basophils, whereas the AT-SP cells had fewer organelles and a higher N/C ratio than the BM-SP cells. This suggests that the AT-SP cells are considerably more immature than the BM-SP cells. Thus, it appears that AT is a better source of immature non-hematopoietic cells than BM.
authors.affiliation: Department of Pediatrics, Nippon Medical School, Tokyo, Japan ; Department of Pharmacology, Nippon Medical School, Tokyo, Japan.
authors.forename: Juri
authors.initials: J
authors.lastname: Fujimura
authors.affiliation: Tumor Stem Cell Team, Biological Research Group, Pharmaceutical Research Laboratories, Research & Development Group, Nippon Kayaku Co. Ltd., Tokyo, Japan.
authors.forename: Hidemitsu
authors.initials: H
authors.lastname: Sugihara
authors.affiliation: Department of Pediatrics, Nippon Medical School, Tokyo, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Fukunaga
authors.affiliation: Department of Pharmacology, Nippon Medical School, Tokyo, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Plastic, Reconstructive and Aesthetic Surgery, Nippon Medical School, Tokyo, Japan ; Division of Plastic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: Rei
authors.initials: R
authors.lastname: Ogawa
keywords: Adipose stem cells; Adipose tissue; Adipose-derived stem cells; Bone marrow; Mesenchymal stem cells; Sp cells