Construction of a eukaryotic expression system for granulysin and its protective effect in mice infected with Mycobacterium tuberculosis

Abstract
A full-length cDNA of granulysin was inserted into the pcDNA3.1(−) vector to construct a eukaryotic expression plasmid for granulysin. The recombinant plasmids were injected intramuscularly into mice infected withMycobacterium tuberculosisto evaluate the protective effect of granulysin. Granulysin significantly decreased the weight index (WI) of the spleen, reduced the numbers of viable bacteria in lung and spleen, and reduced the lesions of lung tissue in granulysin-rDNA-immunized mice compared with those of control group mice.In vitro, the serum of the recombinant-plasmid-immunized mice inhibited the viability ofM. tuberculosisby the physical disruption of cell membranes. Therefore, granulysin has a therapeutic effect againstM. tuberculosis.