Components of gene therapy experimentation that contribute to relative risk

Gene therapy is the purposeful delivery of genetic material to somatic cells for the purpose of treating disease or biomedical investigation. Either viral or non-viral vector methods can be used. The risk of collateral exposure of laboratory animal care personnel to gene therapy vectors is dependent on a number of factors. These factors are intrinsic to the gene therapy vector (the vehicle for genetic conveyance), product encoded by the genetic construct delivered, method of delivery, and immune status of the recipient. The component risks of gene therapy experiments can be analyzed to surmise the overall relative risk of the experiment. Knowledge of the components that contribute potential hazardous risk to a study can assist animal care staff in identifying area(s) where prudent practices should be focused. Gene therapy experiments involving viral vectors are generally performed at either biosafety level 2 or 3. The objective of this review is to report on various components of gene therapy experiments, focusing on characteristics of viral and non-viral vectors, to assist the laboratory animal science community in determining prudent biosafety practices.