OBJECTIVETo compare the efficiency of three different serotypes of adeno-associated virus (AAV) in mediating the transfection of enhanced green fluorescent protein (EGFP) in Tibet minipig fetal fibroblasts (PFFs).

METHODSThree recombinant AAV of different serotypes encoding EGFP were constructed and transfected into primary cultured PFFs at the multiplicity of infection (MOI) ranging from 10(3) to 10(5). The expression rates of EGFP in the PFFs were assessed 72 h after the infection by flow cytometry, and the transfected PFFs were observed under inverted fluorescence microscope. The toxicity of AAVs to PFFs was analyzed using MTT assay.

RESULTSThe transfection efficiency of AAV2-EGFP increased with MOI. At the MOI of 10(3), the transfection efficiency of AAV2-EGFP was (33.68∓1.18)%, which increased to (50.80∓2.59)% at the MOI of 10(4) but without obvious further increase at the MOI of 10(5). The other two serotypes of the virus (AAV8 and AAV9) showed no obvious changes in the infection efficiency at any MOIs. The transfection efficiency of AAV8 was (8.3∓0.02)% and that of AAV9 was (2.20∓1.02)% at the MOI of 10(5). Transfection with the 3 viruses caused no adverse effects on the normal cell growth of the PFFs.

CONCLUSIONSAAV2 has a significantly higher infection rate in cultured PFFs than AAV8 and AAV9, and the latter two have a rather low infection efficiency. All the three AAVs have no cell toxicity to the PFFs.