Recombinant viral vectors

Abstract

The present relation relates to recombinant vesicular stomatitis virus for use as prophylactic and therapeutic vaccines for infectious diseases of AIDS. The present invention encompasses the preparation and purification of immunogenic compositions which are formulated into the vaccines of the present invention.

1 . A recombinant vesicular stomatitis virus (VSV) vector wherein the gene encoding the VSV surface glycoprotein G (VSV G) is functionally replaced by HIV Env. 
     
     
         2 . The vector of  claim 1  wherein the HIV Env is recognized by antibodies PG9, PG16, 2G12, b12, 2F5, 4E10 or Z13, or other Env-specific antibodies, including broad potent neutralizing trimer-specific antibodies. 
     
     
         3 . A recombinant vesicular stomatitis virus (VSV) vector encoding a modified form of VSV G, wherein the modified form of VSV G harbors natural or modified epitopes from the HIV Env membrane proximal external region (MPER). 
     
     
         4 . The vector of  claim 3  wherein the MPER sequence is inserted into the membrane proximal region of VSV G. 
     
     
         5 . The vector of  claim 3  wherein a G-MPER protein binds with high avidity to 2F5 and 4E10 monoclonal antibodies. 
     
     
         6 . A recombinant vesicular stomatitis virus (VSV) vector encoding a an N-terminally truncated form of VSV G (G/Stem), wherein the G/Stem presents Env epitope sequences on the surface of VSV particles. 
     
     
         7 . The vector of  claim 6  wherein G/Stem contains a cytoplasmic tail (CT) and trans-membrane (TM) spanning domains of G, a 16- to 68-amino acid membrane proximal extracellular polypeptide (the Stem), wherein HIV Env epitopes are appended to the Stem. 
     
     
         8 . The vector of  claim 7  wherein the HIV Env epitopes are MPER epitopes. 
     
     
         9 . The vector of  claim 8  wherein the G/Stem-MPER molecules bind to 2F5 and 4E10 monoclonal antibodies with high affinity. 
     
     
         10 . A method of generating novel chimeric EnvG molecules expressed and incorporated into VSV comprising:
 (a) serially passaging replication-competent chimeric VSV-HIV viruses that lack the capacity to encode wild-type G and are dependent on Env or EnvG for infection and propagation on cells to promote emergence of viruses with greater replicative fitness and   (b) identifying novel mutations that enhance Env or EnvG function.   
     
     
         11 . The method of  claim 10 , wherein the cells are CD4/CCR5 +  cells. 
     
     
         12 . The method of  claim 10  wherein the novel mutations escalate trimer abundance on the virus particle and/or increase the stability of the functional trimeric form of Env or EnvG. 
     
     
         13 . The method of  claim 10  further comprising determining whether the Env or EnvG immunogens bind and elicit broadly neutralizing anti-Env antibodies. 
     
     
         14 . The method of  claim 10  further comprising applying selective pressure to generate novel Env or EnvG molecules expressed and incorporated into VSV, wherein the selective pressure is binding to broad and potent neutralizing antibodies. 
     
     
         15 . The method of  claim 14  wherein the antibody is PG9, PG16, b12, 2G12, 2F5 or 4E10 or any other broad potent neutralizing Env trimer specific antibody. 
     
     
         16 . A method of producing an immune response or eliciting an immune response comprising administering to a mammal the vector of any one of  claim 1 ,  3  or  6 .