FIG. 1.

Immunization with nonintegrating lentivectors. (A) All vectors have an invariant chain-OVA fusion (IiOVA) expressed under the control of the ubiquitin promoter and EGFP, activated MKK6, or vFLIP under the control of the SFFV promoter. Mutations in the attachment sites within the LTRs are indicated with arrows. LTR, HIV-1 LTR; ψ, HIV packaging signal; RRE, Rev response element; cPPT, central polypurine tract; UBI, human ubiquitin promoter; ΔU3 LTR, LTR with a deletion in the U3 region. (B) HIV-1 integrase consists of three domains: the N-terminal domain, the C-terminal domain, and a catalytic core domain. Mutations were introduced in two residues within the catalytic core (D64 and N120) and in one residue within the N-terminal domain (W235). (C) Summary of mutations within the expression and packaging plasmid for each of the vectors. WT, wild type. (D) OVA mRNA expression in lymph nodes. Samples were prepared from draining lymph nodes at 24 and 72 h after subcutaneous injection of 500 ng RT of the WT, DNW/2Δatt, MKK6/DNW, and vFLIP/DNW vectors as shown. (E) CD8⁺ T-cell responses to immunization. The x axis shows the dose of vector used for immunization measure by RT ELISA. The y axis depicts the number of IFN-γ spots per 10⁶ splenocytes. The heat-inactivated control is 250 ng RT of WT vector inactivated at 95°C for 15 min.