Objective        To construct a Lactococcus lactis system which could express the truncated F1 protein (F

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) of human respiratory syncytial virus and to identify the immunoreactivity of the obtained protein in order to evaluate the possibility of recombinant bacteria as an oral vaccine.       Methods        Firstly

egfp and f

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gene were amplified by PCR

and then the product was inserted into the pMD18T vector for sequencing. Secondly

recombinant bacteria pMG36e-egfp/MG1363 and pMG36e-f

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/MG1363 were constructed. Finally

fluorescence microscopy

SDS-PAGE and

Western blotting were used to investigate the expressed protein.       Results        Expression of enhanced green fluorescent protein (EGFP) was found in the recombinant bacteria pMG36e-egfp/MG1363. F

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 was detected in the recombinant bacteria by Western blotting.       Conclusion        The protein F

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is correctly expressed by the recombinant Lactococcus lactis with its immunoreactivity.