Relationship between TNF-alpha and TUNEL-positive chondrocytes in antigen-induced arthritis of the rabbit temporomandibular joint.
BACKGROUND
Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end-labeling (TUNEL) staining is a widely accepted method for the detection of DNA fragmentation in nuclei of apoptotic cells. Tumor necrosis factor (TNF)-alpha is closely associated with changes in condylar cartilage and modulates apoptosis in various tissues including cartilage. The aim of this study was to investigate the relationship between apoptotic chondrocytes and TNF-alpha in a rabbit model of arthritis.


METHODS
Unilateral temporomandibular joint (TMJ) arthritis was induced in 20 adult New Zealand White rabbits. From 1 day to 6 weeks after the induction of arthritis, immunohistochemical analysis for TNF-alpha and TUNEL was performed.


RESULTS
In condylar cartilage, TNF-alpha-positive cells and TUNEL-positive cells were localized together. TNF-alpha-positive chondrocytes seemed to precede TUNEL-positive cells.


CONCLUSIONS
The results of the present study suggest that TNF-alpha may be involved in apoptosis and/or apoptotic necrosis of chondrocytes as TMJ arthritis progresses from the acute to chronic stage.
Hirota
Yuriko
Y
Department of Oral and Maxillofacial Surgery, Kyushu Dental College, Kitakyushu, Japan.
Habu
Manabu
M
Tominaga
Kazuhiro
K
Sukedai
Miho
M
Matsukawa
Akihiro
A
Nishihara
Tatsuji
T
Fukuda
Jinichi
J
D000818:Animals; D000941:Antigens / Q000276:immunology; D017209:Apoptosis; D001169:Arthritis, Experimental / Q000473:pathology*; D002356:Cartilage / Q000473:pathology; D002467:Cell Nucleus / Q000648:ultrastructure; D049109:Cell Proliferation; D019902:Chondrocytes / Q000473:pathology*; D053938:DNA Fragmentation; D004195:Disease Models, Animal; D018450:Disease Progression; D006984:Hypertrophy; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D008297:Male; D008335:Mandibular Condyle / Q000473:pathology; D009336:Necrosis; D010047:Ovalbumin / Q000276:immunology; D011817:Rabbits; D013705:Temporomandibular Joint Disorders / Q000276:immunology / Q000473:pathology*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*
D000941:Antigens; D014409:Tumor Necrosis Factor-alpha; D010047:Ovalbumin