title: Identification and functional characterization of ion channels in CD34(+) hematopoietic stem cells from human peripheral blood.
abstract: Hematopoietic stem cells (HSCs) are used therapeutically for hematological diseases and may also serve as a source for nonhematopoietic tissue engineering in the future. In other cell types, ion channels have been investigated as potential targets for the regulation of proliferation and differentiation. However, the ion channels of HSCs remain elusive. Here, we functionally characterized the ion channels of CD34(+) cells from human peripheral blood. Using fluorescence-activated cell sorting, we confirmed that the CD34(+) cells also express CD45 and CD133. In the CD34(+)/CD45(+)/CD133(high) HSCs, RT-PCR of 58 ion channel mRNAs revealed the coexpression of Kv1.3, Kv7.1, Nav1.7, TASK2, TALK2, TWIK2, TRPC4, TRPC6, TRPM2, TRPM7, and TRPV2. Whole-cell patch clamp recordings identified voltage-gated K(+) currents (putatively Kv1.3), pH-sensitive TASK2-like back-ground K(+) currents, ADP-ribose-activated TRPM2 currents, temperature-sensitive TRPV2-like currents, and diacylglycerol-analogue-activated TRPC6-like currents. Our results lend new insight into the physiological role of ion channels in HSCs, the specific implications of which require further investigation.
authors.affiliation: Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang 790-784, Korea.
authors.forename: Kyoung Sun
authors.initials: KS
authors.lastname: Park
authors.forename: Bo
authors.initials: B
authors.lastname: Pang
authors.forename: Su Jung
authors.initials: SJ
authors.lastname: Park
authors.forename: Yun-Gyoo
authors.initials: YG
authors.lastname: Lee
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Bae
authors.forename: Seonyang
authors.initials: S
authors.lastname: Park
authors.forename: Inho
authors.initials: I
authors.lastname: Kim
authors.forename: Sung Joon
authors.initials: SJ
authors.lastname: Kim
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D018952:Antigens, CD34 / Q000096:biosynthesis; D000943:Antigens, Differentiation / Q000378:metabolism; D002469:Cell Separation; D002478:Cells, Cultured; D005434:Flow Cytometry; D006402:Hematologic Diseases / Q000628:therapy*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007473:Ion Channels / Q000737:chemistry / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D024642:Potassium Channels, Voltage-Gated / Q000737:chemistry / Q000378:metabolism*; D033581:Stem Cell Transplantation; D013696:Temperature
chemical_list: D018952:Antigens, CD34; D000943:Antigens, Differentiation; D007473:Ion Channels; D024642:Potassium Channels, Voltage-Gated; D000244:Adenosine Diphosphate