Journal: The Journal of Experimental Medicine

Article Title: Early type I IFN blockade improves the efficacy of viral vaccines

doi: 10.1084/jem.20191220

Figure Lengend Snippet: Effects of short-term IFN-I blockade on experimental SIV/HIV vaccines. (A) Validation of the IFNAR1 antibody (MAR1-5A3) in vitro. CT2A cells were incubated with 20 µg of IgG1 (MOPC-21) or IFNAR1-blocking antibody (MAR1-5A3) for 30 min before treatment with IFN-I (1,000 units) overnight. Representative histograms of MHC-I expression are shown. Note that MHC-I expression is induced by IFN-I signaling. (B) C57BL/6 mice were immunized intramuscularly with 10 4 PFU of LCMV-SIV mixed with 100 µg of control antibodies or IFNAR1-blocking antibodies, similar to . Representative histograms of phosphorylated STAT1 (pSTAT1) in whole PBMCs 1 d after infection (naive levels represented by dashed histogram, which overlapped with the αIFNAR1 group). Note that pSTAT1 is induced by IFN-I signaling. (C) Representative FACS plots showing the frequencies of LCMV- and SIV-specific CD8 T cells (gated from live CD8 + lymphocytes) in spleen, lymph nodes, and liver. (D) Summary of LCMV- and SIV-specific CD8 T cells in spleen, lymph nodes, and liver. (E) In vitro SIV neutralization in LCMV-SIV–immunized mice; sera from IgG1- or αIFNAR1-treated mice were tested for their ability to neutralize SIV in vitro. Neutralization was measured by TZM-bl assay. (F) Representative FACS plots showing the frequencies of germinal center (GC) B cells in draining lymph nodes (gated from live CD3 − B220 + IgM − IgD − lymphocytes) at day 14. PNA, peanut agglutinin. (G) Levels of antibody that bind to heterologous HIV-1 (SF162, clade B envelope) at day 14. (H) Weight of mice following LCMV-HIV vaccination. (I) Representative FACS plots showing the frequencies of HIV-specific CD8 (left) and CD4 (right) T cells (gated from live CD8 + or CD4 + lymphocytes). (J) Summary of HIV-specific CD8 T cells that are double (IFNγ + TNFα + ) producers. (K) Summary of HIV-specific CD8 T cells that are triple (IFNγ + TNFα + IL-2) producers. (L) Summary of HIV-specific CD4 T cells that are double (IFNγ + TNFα + ) producers. (M) Summary of HIV-specific CD4 T cells that are triple (IFNγ + TNFα + IL-2) producers. Data in panels C and D are from day 48 after infection. All other panels are from day 14 after infection. All experiments were performed at least twice with n = 5–7 mice per group per experiment; data are from one representative experiment. *, P < 0.05; **, P < 0.01; ***, P < 0.001 by the Mann-Whitney U test. Error bars represent SEM.

Article Snippet: IgG isotype control (MOPC-21) or IFN-I receptor subunit 1 (IFNAR1)–blocking antibodies (MAR1-5A3) were purchased from BioXCell or Leinco and diluted in sterile PBS.

Techniques: Vaccines, Biomarker Discovery, In Vitro, Incubation, Blocking Assay, Expressing, Control, Infection, Neutralization, MANN-WHITNEY