Enhanced mRNA expression of Th1 cytokines and IL-12 in active pulmonary sarcoidosis.
OBJECTIVE
Active sarcoidosis is considered to be a Th1 dominant condition. We examined whether Th1 cytokines are highly expressed at inflammed lesions of Japanese patients with sarcoidosis.


METHODS
To investigate the mRNA expression of Th1 cytokines and IL-12 in sarcoid BAL cells, we used semiquantitative reverse transcription--polymerase chain reaction method.


RESULTS
The mRNA expressions of Th1 cytokines (IFN-gamma and IL-2) in active sarcoid BAL cells were significantly elevated as compared with those in healthy volunteers. The proportion of positive IL-4 mRNA expression in sarcoid BAL cells was not significantly higher than that in healthy volunteers. Further, there was no significant difference in IFN-gamma mRNA levels between the groups positive and negative for IL-4 mRNA expression. Although the proportion of positive expression of IL-12 mRNA in active sarcoid BAL cells was not significantly higher than that in healthy volunteers, the group positive for IL-12 mRNA expression had significantly elevated levels of IFN-gamma mRNA than did the negative group.


CONCLUSIONS
These results may indicate that IL-12 induces IFN-gamma expression and subsequent Th1 dominant condition in Japanese patients with sarcoidosis.
Shigehara
K
K
Third Department of Internal Medicine, Sapporo Medical University School of Medicine. kenshin@jade.dti.ne.jp
Shijubo
N
N
Ohmichi
M
M
Kon
S
S
Shibuya
Y
Y
Takahashi
R
R
Morita-Ichimura
S
S
Tatsuno
T
T
Hiraga
Y
Y
Abe
S
S
Sato
N
N
D000328:Adult; D018893:Bronchoalveolar Lavage; D018929:Cell Culture Techniques; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000235:genetics; D018664:Interleukin-12 / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017565:Sarcoidosis, Pulmonary / Q000235:genetics / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D012333:RNA, Messenger; D018664:Interleukin-12; D007371:Interferon-gamma