Bcl-2 family expression in salivary glands from patients with primary Sjögren's syndrome: involvement of Bax in salivary gland destruction.
To investigate the molecular mechanism of glandular parenchyma destruction in Sjögren's syndrome (SS), Bcl-2, Bax, Bcl-X, and Bak expression were studied. SS (n = 18) and control salivary glands (n = 6) were examined by immunohistochemistry. Apoptosis was assessed by in situ DNA nick end labeling. Infiltrating mononuclear cells in the SS salivary gland showed elevated Bcl-2. These mononuclear cells expressed increased Bax but did not undergo apoptosis. Both SS and control salivary gland ductal epithelial cells expressed Bcl-2, Bax, and Bcl-X. SS, but not normal, salivary gland acinar cells expressed Bax and underwent apoptosis. These results suggest that elevated Bax expression in SS salivary gland acinar cells may play an important role in the apoptotic pathway. In contrast, Bcl-2 expression in SS infiltrating mononuclear cells and ductal cells may contribute to their survival.
Division of Clinical Immunology, The University of Texas Health Science Center at San Antonio, San Antonio, Texas, 78284, USA.
L
L
Kong
N
N
Ogawa
H S
HS
McGuff
T
T
Nakabayashi
K M
KM
Sakata
R
R
Masago
N
N
Vela-Roch
N
N
Talal
H
H
Dang
D017209:Apoptosis / Q000502:physiology; D004848:Epithelium / Q000378:metabolism / Q000502:physiology; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008565:Membrane Proteins / Q000096:biosynthesis; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000502:physiology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis* / Q000502:physiology; D018987:Salivary Ducts / Q000737:chemistry / Q000166:cytology / Q000378:metabolism; D012469:Salivary Glands / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D012859:Sjogren's Syndrome / Q000378:metabolism*; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein
C494772:BAK1 protein, human; C494826:BAX protein, human; C494811:BCL2L1 protein, human; D008565:Membrane Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051028:bcl-2-Associated X Protein; D051020:bcl-X Protein