Necessity of extracellular domain of W (c-kit) receptors for attachment of murine cultured mast cells to fibroblasts.
The receptor encoded by the W (c-kit) locus (W receptor) is expressed on the surface of cultured mast cells (CMC) derived from normal (+/+) mice, whereas its ligand encoded by the Sl locus (Sl ligand) is expressed on the surface of fibroblast cell lines derived from murine embryos. Involvement of W receptors and Sl ligands in attachment of CMC to fibroblasts was investigated. CMC were cocultured with fibroblasts; nonattaching CMC were removed and the remaining CMC were counted. CMC derived from mice of the W/W genotype did not express the extracellular domain of W receptors, and attachment of W/W CMC to +/+ fibroblasts was significantly impaired. Fibroblasts derived from embryos of the Sl/Sl genotype did not express Sl ligands, and the attachment of +/+ CMC to Sl/Sl fibroblasts was also impaired. The Wv and W42 alleles are point mutations at the intracellular tyrosine kinase domain. Attachment of either Wv/Wv, W/Wv, or W/W42 CMC to +/+ fibroblasts was comparable with that of +/+ CMC. Moreover, the addition of monoclonal antibody against the extracellular domain of W receptors inhibited the attachment of +/+ CMC to +/+ fibroblasts. Thus, the extracellular domain of W receptors appeared to be necessary for attachment of CMC to fibroblasts.
Department of Pathology, Osaka University Medical School, Suita, Japan.
S
S
Adachi
Y
Y
Ebi
S
S
Nishikawa
S
S
Hayashi
M
M
Yamazaki
T
T
Kasugai
T
T
Yamamura
S
S
Nomura
Y
Y
Kitamura
D000483:Alleles; D000818:Animals; D002448:Cell Adhesion; D002478:Cells, Cultured; D005110:Extracellular Space; D005347:Fibroblasts / Q000166:cytology*; D007158:Immunologic Techniques; D066298:In Vitro Techniques; D008407:Mast Cells / Q000166:cytology*; D051379:Mice; D008817:Mice, Mutant Strains; D011518:Proto-Oncogene Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D019009:Proto-Oncogene Proteins c-kit; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
D011518:Proto-Oncogene Proteins; D011956:Receptors, Cell Surface; D019009:Proto-Oncogene Proteins c-kit