Expression of neutrophil gelatinase-associated lipocalin in human salivary glands.
OBJECTIVE
We performed an observational study of RNA and protein expression in human tissue to examine the distribution of neutrophil gelatinase-associated lipocalin (NGAL) in normal and chronic inflammatory salivary tissues, and to investigate the expression level of NGAL in inflammatory conditions of salivary glands.


METHODS
Normal salivary gland tissues and tissue samples of salivary glands with chronic sialadenitis were obtained. Expression of NGAL was investigated by reverse transcriptase-polymerase chain reaction, and semiquantitative analysis of these results was also performed. The differential localization and amount of immunoreactivity to NGAL protein was evaluated by immunohistochemistry and Western blot analysis in normal salivary gland tissues and salivary glands with chronic sialadenitis.


RESULTS
NGAL messenger RNA transcripts were detected in the tissues from the salivary glands with chronic sialadenitis, but only a small amount was detected in the tissues from the normal salivary glands. A weak expression of NGAL protein was occasionally seen in a few ductal epithelial cells of normal salivary gland tissue. However, in tissue samples from glands with chronic sialadenitis, the NGAL protein was expressed strongly in ductal epithelial cells and infiltrating inflammatory cells.


CONCLUSIONS
These results imply that NGAL is associated with the regulation of inflammation in salivary glands.
Woo
Jeong-Soo
JS
From the Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of Medicine, Seoul, Korea.
Kim
Kyoung-Min
KM
Kang
Jae Seong
JS
Zodpe
Prakash
P
Chae
Sung-Won
SW
Hwang
Soon-Jae
SJ
Lee
Heung-Man
HM
D000209:Acute-Phase Proteins / Q000235:genetics*; D015153:Blotting, Western; D002908:Chronic Disease; D005786:Gene Expression Regulation / Q000502:physiology; D006801:Humans; D007124:Immunoenzyme Techniques; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012793:Sialadenitis / Q000235:genetics* / Q000473:pathology; D013363:Submandibular Gland / Q000378:metabolism* / Q000473:pathology; D013364:Submandibular Gland Diseases / Q000235:genetics* / Q000473:pathology
D000209:Acute-Phase Proteins; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger