title: Hemopoietic stem cell inhibitor (SCI/MIP-1 alpha) also inhibits clonogenic epidermal keratinocyte proliferation.
abstract: The maintenance and regulation of continuously renewing tissues is ultimately controlled at the level of stem-cell proliferation. We have recently identified a reversible inhibitor of hemopoietic stem-cell proliferation (stem-cell inhibitor [SCI]), which is identical to the macrophage inflammatory protein, MIP-1 alpha, a 69-amino-acid heparin-binding cytokine. To test the cell/tissue specificity of the inhibition of proliferation by SCI/MIP-1 alpha, we have investigated its activity on epidermal keratinocytes, the principal cell type of another continuously renewing tissue. Here we show that SCI/MIP-1 alpha inhibits the proliferation of epidermal keratinocytes in vitro and that the MIP-1 alpha mRNA is present in epidermal Langerhans cells but not in keratinocytes. This suggests an important growth regulatory function for SCI/MIP-1 alpha in keratopoiesis, as well as hemopoiesis, and may also indicate a novel role for the epidermal Langerhans cell. As SCI/MIP-1 alpha can inhibit the proliferation of embryologically distinct precursor cells, this raises the possibility that it may also function in a number of other tissues.
authors.affiliation: CRC Beatson Laboratories, Beatson Institute for Cancer Research, Bearsden, Glasgow, U.K.
authors.forename: E K
authors.initials: EK
authors.lastname: Parkinson
authors.forename: G J
authors.initials: GJ
authors.lastname: Graham
authors.forename: P
authors.initials: P
authors.lastname: Daubersies
authors.forename: J E
authors.initials: JE
authors.lastname: Burns
authors.forename: C
authors.initials: C
authors.lastname: Heufler
authors.forename: M
authors.initials: M
authors.lastname: Plumb
authors.forename: G
authors.initials: G
authors.lastname: Schuler
authors.forename: I B
authors.initials: IB
authors.lastname: Pragnell
mesh_terms: D000818:Animals; D015152:Blotting, Northern; D002455:Cell Division / Q000187:drug effects; D054407:Chemokine CCL4; D016207:Cytokines / Q000032:analysis / Q000235:genetics / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology*; D007801:Langerhans Cells / Q000737:chemistry; D019402:Macrophage Inflammatory Proteins; D051379:Mice; D015846:Monokines / Q000032:analysis / Q000235:genetics / Q000494:pharmacology*; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D054407:Chemokine CCL4; D016207:Cytokines; D019402:Macrophage Inflammatory Proteins; D015846:Monokines; D012333:RNA, Messenger