Methods, agents and peptides for inducing an innate immune response in HIV vaccination
The present invention relates to enhancing, modulating or stimulating the innate immune response to HIV-1 and other viral pathogens and to the modulation and application of immune modulators and peptides for HIV-1 or other pathogen vaccines. The invention provides methods and means to activate an innate response to HIV-1 utilizing or via the HIV capsid protein or peptide, including modulating the binding of cyclophilin A to HIV capsid protein and modulating the ability of HIV to activate the major innate transcription factor IRF3 and interferon. Methods and assays are provided for screening for compounds, agents, or peptides capable of enhancing or activating innate immune response, particularly to HIV-1.
1. A method for stimulating or enhancing innate immune response to HIV-1 comprising administering in an immunogenic composition HIV-1 viral particles comprising a Vpx protein and a replication defective HIV-1 vector encoding an HIV-1 Gag polypeptide (SEQ ID NO: 4), wherein the Vpx protein is fused to a Vpr protein in a Vpx-Vpr fusion protein comprising SEQ ID NO: 51 and the Vpr protein of the Vpx-Vpr fusion protein facilitates incorporation of the Vpx-Vpr fusion protein into the HIV-1 viral particles.
2. The method of claim 1 , wherein dendritic cells are targeted for cellular uptake or delivery.
3. The method of claim 1 , wherein dendritic cells are infected by the HIV-1 viral particles following administration of the immunogenic composition and activated and express one of more of CD86, CD80, CD38, CD83, interferon, and a Type-I interferon response signature gene.
4. The method of claim 1 , further comprising assessing adaptive immunity, wherein adaptive immunity activation is detected as an increase in at least one of HIV-specific CD4+ T cells, HIV-specific CD8+ T cells, or naive CD4+ T cells.
5. The method of claim 1 , wherein trans-infection of CD4+ T cells is inhibited.
6. The method of claim 1 , wherein the Vpx-Vpr fusion protein is encoded by SEQ ID NO: 10.
7. The method of claim 1 , wherein the replication defective HIV-1 vector is missing at least one gene or activity essential for HIV-1 replication and/or budding.
8. The method of claim 7 , wherein the replication defective HIV-1 vector is an envelope-deficient HIV-1 vector; comprises a PTAP mutant comprising a mutation that inactivates the PTAP motif in p6; or is a vif-deficient, vpr-deficient, vpu-deficient, or nef-deficient HIV-1 vector.
9. The method of claim 1 , wherein the replication defective HIV-1 vector is HIVGFP (SEQ ID NO: 14).
10. The method of claim 9 , wherein the replication defective HIV-1 vector is HIVGFP (SEQ ID NO: 14), excluding nucleotides 6863-7579 of SEQ ID NO: 14.
11. The method of claim 1 , further comprising detecting at least one of dendritic cell activation or suppression of viral replication in T cells, wherein the dendritic cell activation or suppression of viral replication in T cells is positively correlated with stimulation or enhancement of the innate immune response to HIV.
12. The method of claim 1 , wherein the immunogenic composition consists essentially of HIV-1 viral particles comprising a Vpx protein and a replication defective HIV-1 vector encoding an HIV-1 Gag polypeptide (SEQ ID NO: 4), wherein the Vpx protein is fused to a Vpr protein in a Vpx-Vpr fusion protein comprising SEQ ID NO: 51 and the Vpr protein of the Vpx-Vpr fusion protein facilitates incorporation of the Vpx-Vpr fusion protein into the HIV-1 viral particles, and a pharmaceutically acceptable carrier.