[Nitric oxide production and expression of cytokines by macrophages infected by M. tuberculosis H(37)R(v)].
OBJECTIVE
To study nitric oxide (NO) production and cytokine expression by macrophages infected by M. tuberculosis H(37)R(v), and to compare the difference between dead and live M. tuberculosis in the induction of immune responses, and thus to show if dead bacteria could be a possible candidate for new vaccines.


METHODS
Reverse transcription-polymerase chain reaction (RT-PCR) and ELISA were used to measure the production of NO and cytokines in macrophages infected by H(37)R(v).


RESULTS
Macrophages infected by viable M. tuberculosis produced more NO, IL-1, IL-12, IL-18, TNF-alpha and inducible nitric oxide synthases (iNOS), as compared with macrophages infected by dead bacteria. The number of bacteria was also an important factor determining the production of NO and cytokines.


CONCLUSIONS
Viable M. tuberculosis H(37)R(v) can induce the activation of macrophages and the production of more NO and cytokines which play important roles in the host immune response. Heat-killed M. tuberculosis H(37)R(v) failed to induce activation of macrophages and the production of NO and cytokines, which makes it unlikely to be a candidate for vaccine development.
Li
Chuan-you
CY
Beijing Tuberculosis & Thoracic Tumor Research Institute, Beijing 101149, China.
Xing
Ai-ying
AY
Li
Liang
L
Wei
Pan-jian
PJ
Gu
Shu-xiang
SX
Chen
Xiao-you
XY
Duan
Hong-fei
HF
Chen
Xi
X
Xie
Li
L
Ma
Yu
Y
D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis; D008262:Macrophage Activation; D008264:Macrophages / Q000378:metabolism* / Q000382:microbiology*; D009169:Mycobacterium tuberculosis; D009569:Nitric Oxide / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D016207:Cytokines; D007375:Interleukin-1; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide