Expression of granzyme A in salivary gland biopsies from patients with primary Sjögren's syndrome.
OBJECTIVE
To determine whether the destruction of salivary gland epithelial cells in Sjögren's syndrome (SS) could be mediated by granzyme A, a serine protease that is contained in the granules of activated lymphocytes.


METHODS
We used in situ hybridization and polymerase chain reaction amplification to determine the expression of granzyme A messenger RNA (mRNA) in salivary gland biopsy samples.


RESULTS
Granzyme A mRNA expression was detected in salivary glands from SS patients, but not in those from normal controls. Granzyme A mRNA content was significantly correlated (P < 0.001) with the size of lymphocytic infiltrates in the salivary glands and with the clinical activity of the disease.


CONCLUSIONS
Cells that express granzyme A mRNA may play a role in the destruction of the target organ (i.e., the salivary gland) in patients with SS. The strong association of granzyme A mRNA expression and larger lymphoid infiltrates in the patients' salivary glands suggests that granzyme A mRNA is expressed at a relatively late stage of the local inflammatory process. Therapies designed to modulate or block granzyme A induction and action should be investigated in SS patients.
Stanford University Medical Center, California.
S
S
Alpert
H I
HI
Kang
I
I
Weissman
R I
RI
Fox
D000328:Adult; D000368:Aged; D001483:Base Sequence; D001706:Biopsy; D002675:Child, Preschool; D005260:Female; D053804:Granzymes; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D016131:Lymphocyte Subsets / Q000166:cytology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000032:analysis; D012469:Salivary Glands / Q000201:enzymology* / Q000473:pathology*; D012697:Serine Endopeptidases / Q000235:genetics*; D012859:Sjogren's Syndrome / Q000201:enzymology*
D012333:RNA, Messenger; D053804:Granzymes; D012697:Serine Endopeptidases; C509212:GZMA protein, human