[The construction and expression of eukaryotic expression plasmid of Legionella pneumophila immunogenic protein].

OBJECTIVE

To construct the recombinant plasmid of Legionella pneumophila immunogenic protein gene (ip) and detect the immunoprotein expression in NIH3T3 cells.

METHODS

The immunogenic protein gene was amplified from DNA of Legionella pneumophila by polymerase chain reaction (PCR), then inserted into pcDNA3. 1 (+) vector. The recombinant plasmid was named as pcDNA3. 1-ip and analyzed with restriction-endonuclease Hind III and BamH I digestion, PCR and DNA sequencing techniques. The NIH3T3 cell was transfected by recombinant plasmid pcDNA3. 1-ip with lipofection strategy. The transient and stable expression products of immunogenic protein gene were detected by immunofluorescence and Western blot.

RESULTS

We have successfully constructed the recombinant plasmid of Legionella pneumophila immunogenic protein gene. It was found that there was dark green fluorescence on the cell membrane and inside the cell. Our results showed that NIH3T3 cell was transfected by pcDNA3. 1-ip successfully. The rabbit serum antibody of Legionella pneumophila detected the NIH3T3 cell transfected stably by pcDNA3. 1-ip to express the immunogenic protein with the relative molecular mass 29 X 1093).

CONCLUSION

We have successfully expressed immunogenic protein of Legionella pneumophila. The expressed product showed the good immunogenicity and immunoreactivity.