Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2004-1-7
pubmed:abstractText
In mammalian skin, stem cell factor (SCF) regulates the proliferation and maturation of mast cells and melanocytes, which are thought to be the only cutaneous cells that express the Kit-tyrosine kinase receptor (Kit) and respond to epithelial and mesenchymal-derived SCF. We previously had noted, however, the presence of Kit+ cells in murine hair follicles, in an introepithelial tissue compartment devoid of melanocytes and mast cells. Here we have identified the nature of this Kit+ population of cells in hair follicles of C57BL/6 mice. Anagen hair follicles showed strong Kit immunoreactivity not only in the pigmentary unit above the follicular dermal papilla but also in a much more proximally located, homogenous group of nondendritic, nonmelanized cells. By immunohistochemistry (desmoplakin+/Trp-1-) and electron microscopy (presence of tonofilaments, desmosomes, lack of melanosomes), these Kit+ cells were shown to be hair matrix keratinocytes and were also found in melanocyte-deficient hair follicles (Kit(Sl)/Kit(Sl-d) mice, Kit-neutralizing antibody-treated C57BL/6 mice). Expression of Kit and SCF was strongly hair-cycle-dependent, suggesting a functional role of epithelial Kit expression in hair growth control. This was supported by the observation that mice unable to respond to SCF stimulation (Kit(W)/Kit(W-v)) showed a significant retardation of anagen development compared to their wild-type littermates. The expression of Kit in the most rapidly proliferating compartment of the hair follicle epithelium suggests intriguing, as yet unexplored new functions of Kit signaling in epithelial cell biology.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-202X
pubmed:author
pubmed:issnType
Print
pubmed:volume
121
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
976-84
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Kit is expressed by epithelial cells in vivo.
pubmed:affiliation
Department of Dermatology, University Hospital Hamburg Eppendorf, University of Hamburg, Hamburg, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't