Pseudotype and chimeric viruses
Highly pathogenic viruses with zoonotic potential such as H5N1 influenza viruses, Nipah virus, rabies virus, SARS coronavirus, Lassa fever virus, and Ebola virus require handling in BSL-3/4 containment, which makes diagnosis of and studies on these viruses difficult and expensive. Propagation-incompetent pseudotype viruses represent an elegant solution for this problem. Pseudotype viruses are equipped with the envelope proteins of heterotypic viruses and therefore behave similar to these in terms of cell tropism or antibody-mediated neutralization.
Vesicular stomatitis virus (VSV) is known to incorporate foreign viral glycoproteins in a more or less unspecific manner, in particular in the absence of the VSV G glycoprotein. Pseudotype virus can be generated by propagating the glycoprotein-deficient mutant VSVΔG on cells that express the viral envelope protein of interest. The virus particles released are capable of performing a single round of infection, which is mediated by the incorporated foreign envelope protein. Infection with these pseudotype particles can be easily followed by reporter proteins such as luciferase or GFP, which are encoded by the viral RNA genome. Alternatively, the foreign glycoprotein can be expressed from the VSVΔG genome which may result in propagation-competent chimeric viruses. The pseudotype/chimeric viruses are used in our laboratory for the detection of virus neutralizing antibodies and for analysing viral cell tropism and receptor usage.
- Federal Food Safety and Veterinary Office (grant number 1.13.09): Use of pseudotype replicons particle for the detection of neutralizing antibodies to highly pathogenic viruses.