Identification of mutations in herpes simplex virus envelope glycoproteins that enable or enhance vector retargeting to novel non-HSV receptors
In one embodiment, the invention provides an HSV vector comprising a mutant gB and/or a mutant gH glycoprotein, where the viral envelope further comprises a non-native ligand specific for a protein present on the surface of a predetermined cell type. In another embodiment, the invention provides an HSV vector comprising (a) a mutant gC and/or gD envelope glycoprotein which comprises a non-native ligand specific for a protein present on the surface of a predetermined cell type; and (b) a mutant envelope glycoprotein other than gD.
1. A mutant HSV vector comprising a modified glycoprotein selected from the group consisting of a modified gB glycoprotein and a modified gH glycoprotein, wherein, when the parental vector is HSV1 K26GFP, the modified glycoprotein comprises a substitution in one or more amino acid residues selected from the group consisting of gB:A549, gB:S668, gH:N753, and gH:A778, or wherein when the parental vector is a homologous HSV vector, the modified glycoprotein comprises a substitution in one or more amino acid residues of the homologous HSV vector selected from amino acids that correlate to gB:A549, gB:S668, gH:N753, and gH:A778 of HSV1 K26GFP wherein the gB:A549 residue correlates to X in KLNPNXIAS (SEQ ID NO:2) of HSV1 K26GFP, the gB:S668 residue correlates to X in ITTVXTFID (SEQ ID NO:3) of HSV1 K26GFP, the gH:N753 residue correlates to X in VDTDXTQQQ (SEQ ID NO:4) of HSV1 K26GFP, and the gH:A778 residue correlates to X in VPSTXLLLF (SEQ ID NO:5) of HSV1 K26GFP; and wherein the homologous HSV vector is an HSV-1 or HSV-2 vector, and wherein the mutant HSV exhibits enhanced entry into B78/TMC or B78H1 cells relative to the parental HSV vector.
2. The mutant HSV vector according to claim 1 , wherein the substitution at residue gB:A549 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector replaces the residue with a threonine.
3. The mutant HSV vector according to claim 1 , wherein the substitution at residue gB:S668 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector replaces the residue with an asparagine.
4. The mutant HSV vector according to claim 1 , wherein the substitution at residue gH:N753 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector replaces the residue with a lysine.
5. The mutant HSV vector according to claim 1 , wherein the substitution at residue gH:A778 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector replaces the residue with a valine.
6. The mutant HSV vector according to claim 1 , wherein, when the vector is HSV1 K26GFP, the vector comprises a substitution in the amino acid residue gB:D285, or wherein when the vector is a homologous HSV vector, an amino acid that correlates to gB:D285 of HSV1 K26GFP, wherein the gB:D285 residue correlates to X in VYPYXEFVL (SEQ ID NO: 1) of HSV1 K26GFP.
7. The mutant HSV vector according to claim 6 , wherein the substitution at residue gB:D285 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector replaces the residue with an asparagine.
8. The mutant HSV vector according to claim 1 , wherein the vector comprises a modified gD glycoprotein comprising a substitution in residue gD:A185 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector.
9. The mutant HSV vector according to claim 8 , wherein the substitution at residue gD:A185 of HSV1 K26GFP or the corresponding amino acid in a homologous HSV vector replaces the residue with a threonine.
10. The mutant HSV vector according to claim 1 , wherein the cells are deficient for the gD receptor.
11. The mutant HSV vector according to claim 1 , wherein the enhanced entry into cells comprises an accelerated rate of entry into cells.
12. The mutant HSV vector according to claim 1 , comprising a genome comprising an exogenous expression cassette.
13. The mutant HSV vector according to claim 12 , wherein the expression cassette comprises a target sequence for a cellular microRNA.
14. A viral stock comprising the mutant HSV vector according to claim 1 .
15. A composition comprising the mutant HSV vector according to claim 1 and a pharmaceutical excipient.