[The effect of MTB antigens on the NFAT5 expression in monocytes from human peripheral blood].
OBJECTIVE
To study the effect of Mycobacterium tuberculosis antigens early secretory antigen target 6/culture filtrate protein 10 (ESAT-6/CFP-10) on nuclear factor of activated T-cells 5 (NFAT5) mRNA in monocytes from human peripheral blood.


METHODS
Fifteen patients with active pulmonary tuberculosis (age range: 33-42 y, mean: 37 y, male/female: 9/6) were recruited from the Institute of Tuberculosis in 309 Hospital, and 15 healthy subjects (age range: 37-42 y, mean: 40 y, male/female: 9/6) were recruited from Medical Examination Center of the hospital. Monocytes were isolated from peripheral blood and stimulated with whole cell lysate of H37Rv strain and peptide pool of ESAT-6/CFP-10. Fluorescence quantitative PCR was used to detect the mRNA expression of NFAT5, and differences of NFAT5 mRNA between unstimulated and stimulated monocytes were analyzed by paired t test statistic method.


RESULTS
The expression of NFAT5 mRNA in monocytes from patients with active pulmonary tuberculosis was significantly decreased when stimulated with peptide pool of ESAT-6/CFP-10 compared with unstimulated monocytes (0.18 ± 0.12 vs. 0.23 ± 0.15) (t = 2.591, P < 0.05). Similarly, the expression of NFAT5 mRNA in monocytes from healthy subjects was also significantly decreased when stimulated with peptide pool of ESAT-6/CFP-10 compared with unstimulated monocytes (0.17 ± 0.09 vs 0.21 ± 0.09) (t = 2.828, P < 0.05). However, the expression of NFAT5 mRNA in monocytes stimulated with whole cell lysate was not significantly changed (t = 1.142, P > 0.05), which was 0.28 ± 0.25 and 0.23 ± 0.15 in stimulated and unstimulated monocytes, respectively. Similarly, the expression of NFAT5 mRNA in monocytes from healthy subjects was also not significantly changed when stimulated with whole cell lysate (t = 0.451 9, P > 0.05), which was 0.20 ± 0.12 and 0.21 ± 0.09 in stimulated and unstimulated monocytes, respectively.


CONCLUSIONS
The MTB antigen ESAT-6/CFP-10 can inhibit NFAT5 expression in human monocytes in vitro.
Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing 100091, China.
Yanhua
Y
Liu
Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing 100091, China.
Ruo
R
Wang
Army Tuberculosis Prevention and Control Key Laboratory, Beijing Key Laboratory of New Techniques of Tuberculosis Diagnosis and Treatment, Institute for Tuberculosis Research, the 309th Hospital of Chinese PLA, Beijing 100091, China; Email: xcheng2@139.com.
Xiaoxing
X
Cheng
D000328:Adult; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D005260:Female; D006801:Humans; D008297:Male; D009000:Monocytes; D009169:Mycobacterium tuberculosis; D010455:Peptides; D012333:RNA, Messenger; D060888:Real-Time Polymerase Chain Reaction; D014157:Transcription Factors; D014376:Tuberculosis; D014397:Tuberculosis, Pulmonary
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C118125:NFAT5 protein, human; D010455:Peptides; D012333:RNA, Messenger; D014157:Transcription Factors; C072681:Mycobacterium tuberculosis antigens