Isolation and characterization of synovial cells from the human temporomandibular joint.
BACKGROUND
The synovial tissues with temporomandibular disorders (TMDs) often show chronic inflammatory changes and the synovial cells participate in the pathogenic processes of TMDs. The synovial membrane is composed of a synovial lining layer and a connective sublining layer. The synovial lining layer is made up of two kinds of cells: macrophage-like type A and fibroblastic type B cells. The aim of this study was to isolate and characterize synovial cells from the human temporomandibular joint (TMJ).


METHODS
Synovial cells were isolated using an explant culture method. Then, we characterized the cultured synovial cells (SGA2 cells) using immunocytochemistry.


RESULTS
SGA2 cells expressed the fibroblastic markers vimentin and prolyl 4-hydroxylase; they also expressed laminin and heat shock protein 27, all of which are markers of type B cells. However, some cells expressed the macrophage marker CD68. These CD68-positive cells simultaneously expressed laminin.


CONCLUSIONS
We isolated and cultured synovial type B cells from the human TMJ, and identified the presence of intermediate type synovial lining cells, having the phenotypic properties of both type A and type B cells, among the synovial lining cells.
Nagai
H
H
Division of Dentistry and Oral Surgery, Akita University Hospital, Akita, Japan. hnagai@med.akita-u.ac.jp
Miyamoto
Y
Y
Nakata
A
A
Hatakeyama
S
S
Iwanami
Y
Y
Fukuda
M
M
D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D002469:Cell Separation; D002478:Cells, Cultured; D003239:Connective Tissue Cells / Q000166:cytology; D005347:Fibroblasts / Q000166:cytology; D006360:Heat-Shock Proteins / Q000032:analysis; D006801:Humans; D007150:Immunohistochemistry; D007797:Laminin / Q000032:analysis; D008264:Macrophages / Q000166:cytology; D010641:Phenotype; D011393:Procollagen-Proline Dioxygenase / Q000032:analysis; D013583:Synovial Membrane / Q000166:cytology*; D013704:Temporomandibular Joint / Q000166:cytology*; D014746:Vimentin / Q000032:analysis; D000097382:CD68 Molecule
D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D015415:Biomarkers; D006360:Heat-Shock Proteins; D007797:Laminin; D011393:Procollagen-Proline Dioxygenase; D014746:Vimentin; C067980:CD68 antigen, human; D000097382:CD68 Molecule