Mutations in the Non-Structural Protein-Coding Sequence of Protoparvovirus H-1PV Enhance the Fitness of the Virus and Show Key Benefits Regarding the Transduction Efficiency of Derived Vectors
Hamidreza Hashemi,
Alexandra-Larisa Condurat,
Alexandra Stroh-Dege,
Nadine Weiss,
Carsten Geiss,
Jill Pilet,
Carles Cornet Bartolomé,
Jean Rommelaere,
Nathalie Salomé,
Christiane Dinsart
Affiliations
Hamidreza Hashemi
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Alexandra-Larisa Condurat
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Alexandra Stroh-Dege
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Nadine Weiss
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Carsten Geiss
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Jill Pilet
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Carles Cornet Bartolomé
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Jean Rommelaere
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Nathalie Salomé
Institut National de la Santé et de la Recherche Médicale U701, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
Christiane Dinsart
Infection, Inflammation and Cancer Program, Tumor Virology Division (F010), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, 69120 Heidelberg, Germany
Single nucleotide changes were introduced into the non-structural (NS) coding sequence of the H-1 parvovirus (PV) infectious molecular clone and the corresponding virus stocks produced, thereby generating H1-PM-I, H1-PM-II, H1-PM-III, and H1-DM. The effects of the mutations on viral fitness were analyzed. Because of the overlapping sequences of NS1 and NS2, the mutations affected either NS2 (H1-PM-II, -III) or both NS1 and NS2 proteins (H1-PM-I, H1-DM). Our results show key benefits of PM-I, PM-II, and DM mutations with regard to the fitness of the virus stocks produced. Indeed, these mutants displayed a higher production of infectious virus in different cell cultures and better spreading capacity than the wild-type virus. This correlated with a decreased particle-to-infectivity (P/I) ratio and stimulation of an early step(s) of the viral cycle prior to viral DNA replication, namely, cell binding and internalization. These mutations also enhance the transduction efficiency of H-1PV-based vectors. In contrast, the PM-III mutation, which affects NS2 at a position downstream of the sequence deleted in Del H-1PV, impaired virus replication and spreading. We hypothesize that the NS2 protein—modified in H1-PM-I, H1-PM-II, and H1-DM—may result in the stimulation of some maturation step(s) of the capsid and facilitate virus entry into subsequently infected cells.