Background Live attenuated measles vaccine is based on immunogenecity of F and H viral glycoprotein. Each gene of this virus harbors non-coding regions which are important in controlling the viral coding regions. The 5’-UTR fusion protein gene is one of the non-coding regions which is prone to multiple point mutations and deletions that may affect the function of the fusion protein. Therefore we propose these mutations may have occurred by changing the measles virus cell cultures.
Objective In this research we tried to study the possible changes which may occur in the 5’-UTR non-coding sequence of the F gene after measles virus cell culture changes.
Methods Concerning the importance of F gene and the influence of the non-coding region on the immunogenicity and the tropism of this protein, evaluation was performed by RT-PCR, gene cloning and sequencing methods.
Results In this study the amplified region was cloned in pTZ57R, cloned plasmids were insert into E. coli DH5α, then amplified plasmids extracted from the bacterial cell and sent for sequencing. Comparison of the sequenced F gene 5’-UTR with the gene bank sequence of this region shows no variation and mutation after changing the measles virus cell lines from fibroblast to MRC-5, used for multiplication of measles vaccine strain.
Conclusion On comparison of F gene sequences no detection of mutational changes was observed between them. We conclude that producing a measles virus vaccine strain in the MRC-5 cell line possibly did not lead to changes in the immunogenecity of F protein.