title: Growth related secretion and production of GM-CSF by epithelial cell line.
abstract: Granulocyte-macrophage colony stimulating factor (GM-CSF) is a growth factor that supports the clonal development of normal granulocyte-macrophage progenitors. Especially in the skin, GM-CSF from keratinocytes may be a critical factor in the melanogenesis of the skin. In addition, GM-CSF is thought to play an important role in impaired wound healing. However, little is known regarding the synthesis and secretion of GM-CSF by keratinocytes of the skin. This investigation evaluated the effects of cell density on the production of GM-CSF by keratinocytes and the changes in the cell cycle. Interestingly, GM-CSF protein secretions and mRNA expressions were highly elevated in sub-confluent HaCat cells, and decreased in confluent state. In particular, GM-CSF production decreased in a density-dependent manner. We also found that the percentage of cells in the S phase of the cell cycle decreased markedly from 50 to 10% when HaCat cells reached a confluent state. These results showed that GM-CSF synthesis and secretion by HaCat cells increases when cells are rapidly proliferating such as in the wound healing process. Thus, it might be said that GM-CSF produced by proliferating keratinocytes possibly contributes to wound healing and melanogenesis at the site of injury.
authors.affiliation: Department of Dermatology and Artificial Organ Laboratory, Clinical Research Institute, Seoul National University College of Medicine, Yungon-dong 28, Chongno-gu, 110-744, Seoul, South Korea. gcpark@snu.ac.kr
authors.forename: K C
authors.initials: KC
authors.lastname: Park
authors.forename: D S
authors.initials: DS
authors.lastname: Kim
authors.forename: H J
authors.initials: HJ
authors.lastname: Kim
authors.forename: K I
authors.initials: KI
authors.lastname: Seo
authors.forename: K H
authors.initials: KH
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Chung
authors.forename: H C
authors.initials: HC
authors.lastname: Eun
authors.forename: H C
authors.initials: HC
authors.lastname: Jung
mesh_terms: D002452:Cell Count; D002453:Cell Cycle / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology* / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D016196:S Phase
chemical_list: D012333:RNA, Messenger; D016178:Granulocyte-Macrophage Colony-Stimulating Factor