NP-mPB expression has little effect on cell viability.

<p>To probe the potential cytotoxicity of mPB and NP-mPB expression, HEK293T cells were transfected with different amounts of the mPB, NP-mPB, mPB-tGFP, and NP-mPB-tGFP expression vectors. The relative cell viability was evaluated by the MTS assay. There was no significant difference among the different protein-expressing vectors. n  = 3 for each condition; bars indicate mean ± standard error; <i>P</i>>0.05.</p>