[Study on the detection method for determining the bioactivity of recombinant human interleukin-22].
OBJECTIVE
To develop a method for determining the bioactivity of recombinant human IL-22.


METHODS
pSTAT3-TA-Luc and pcDNA3. 1 plasmids were co-transfect to HepG2 cells to generate stable HepG2/ STAT3 cell line with G418 screen. After treating cell with IL-22, the luciferase activity was assayed. Orthogonal test was used to optimize the assay condition, and then the reproducibility and specificity of the assay was checked.


RESULTS
The best condition for this assay are: cell density as 4 x 10(5)/mL, stimulating time as 4 hours, luciferase substrate as 50 microL. 50% effective dose (ED50) of IL-22 assayed by this method is 16.89 ng/mL, relative standard deviation (RSD) is 7.09%. Neutralizing antibody test shows the high specificity. Comparing with ELISA, the method described here has more advantages, including higher stability, easier performance and less cost.


CONCLUSIONS
Luciferase reporter gene assay method is a fast, sensitive, reproducible method for IL-22 bioactivity determination.
Zhang
Jun-Yao
JY
Department of Biochemistry and Molecular Biology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu 610041, China.
Huang
Zhi-Hua
ZH
Huang
Yu-Liang
YL
Xu
Fei
F
Li
Xiao-Ying
XY
Xing
Rui-Qing
RQ
Fu
Qiang
Q
D001681:Biological Assay / Q000379:methods*; D017930:Genes, Reporter; D056945:Hep G2 Cells; D006801:Humans; D007378:Interleukins / Q000032:analysis*; D008156:Luciferases / Q000378:metabolism*; D011994:Recombinant Proteins / Q000032:analysis*; D050796:STAT3 Transcription Factor / Q000235:genetics*; D000097043:Interleukin-22
D007378:Interleukins; D008156:Luciferases; D011994:Recombinant Proteins; D050796:STAT3 Transcription Factor; D000097043:Interleukin-22