Endpoint titre of 36104) when used alone. Significant increases in specific IgG above antigen alone were seen when TT was administered with FSL-1, Poly I:C, CpG B or chitosan (p = 0.007), while an increase in specific IgA was seen for FSL-1 and chitosan (p = 0.007) (Figure 2A and B). In contrast, co-administration of TT with MPLA significantly decreased systemic IgA responses (p = 0.008). TT administered alone induced poor or undetectable MedChemExpress BIBS39 vaginal IgG responses (Figure 2C), however FSL-1, Poly I:C, and CpG B induced detectable vaginal IgG responses in all animals within each group, although these were still low. However, specific vaginal IgA responses were detectable for all animals receiving TT alone and these responses were similar to those seen with all adjuvants, with the exception of MPLA, which reduced Tetracosactrin titres of specific vaginal IgA (p = 0.015) (Figure 2C and D).Specific IgG subclass analysis demonstrated that TT when given alone induced a balanced systemic IgG1/IgG2a ratio of 0.9 (Figure S1B) and this was maintained with all adjuvants except chitosan which gave a significantly increased IgG1/IgG2a ratio relative to TT alone.Nasal immunisation with gp140 and TTThe administration of gp140 alone via the nasal route induced barely detectable systemic or local IgG and IgA responses. However, all adjuvant candidates tested promoted strong systemic IgG production, giving titres up to 5.336105 (p,0.01) (Figure 3A). Likewise, specific serum IgA titres were induced by all adjuvant candidates with serum titres of up to 3.46104. These were significant for all adjuvants (Figure 3B), however the effect of R848 was significantly lower than that of the other adjuvants for both IgG and IgA (p = 0.01). In vaginal wash samples, all adjuvants significantly increased specific IgG titres (p,0.01), which were below or at the cut-off for detection when gp140 was given alone. FSL-1 and R848 also augmented vaginal IgG responses but to a lesser extent (Figure 3C). For specific IgA, all the 
candidates significantly increased vaginal antibody titres but the enhancement mediated by R848 was significantly lower than that of the other adjuvants (Figure 3D). IgG subclass analysis indicated that all candidates tested significantly increased both specific IgG1 and, with the exception of chitosan, IgG2a antibody titres (p,0.01) (data not shown). gp140 when administered alone gave an IgG1/IgG2a ratio of 3.5. FSL-1, MPLA, Pam3CSK4 and chitosan increased IgG1/IgG2a ratios promoting a Th2 biasing of responses that were significant for Pam3CSK4 and Chitosan. Conversely, poly I:C and CpG-BFigure 1. Sublingual immunisation with gp140. Endpoint titres for IgG (A, C) and IgA (B, D) in sera (upper panels) and vaginal washes (lower panels) from animals immunised three times with gp140 sublingually. Asterisks indicate significant differences between the different adjuvant/ antigen groups and the PBS control group. doi:10.1371/journal.pone.0050529.gMucosal TLR Adjuvants for HIV-gpFigure 2. Sublingual immunisation with Tetanus toxoid. Endpoint titres for IgG (A, C) and IgA (B, D) in sera (upper panels) and vaginal washes (lower panels) from animals immunised three times with Tetanus toxoid sublingually. Asterisks indicate significant differences between the different adjuvant/antigen groups and the PBS control group. doi:10.1371/journal.pone.0050529.gFigure 3. Intranasal immunisation with gp140. Endpoint titres for IgG (A, C) and IgA (B, D) in sera (upper panels) and vaginal wash.Endpoint titre of 36104) when used alone. Significant increases in specific IgG above antigen alone were seen when TT was administered with FSL-1, Poly I:C, CpG B or chitosan (p = 0.007), while an increase in specific IgA was seen for FSL-1 and chitosan (p = 0.007) (Figure 2A and B). In contrast, co-administration of TT with MPLA significantly decreased systemic IgA responses (p = 0.008). TT administered alone induced poor or undetectable vaginal IgG responses (Figure 2C), however FSL-1, Poly I:C, and CpG B induced detectable vaginal IgG responses in all animals within each group, although these were still low. However, specific vaginal IgA responses were detectable for all animals receiving TT alone and these responses were similar to those seen with all adjuvants, with the exception of MPLA, which reduced titres of specific vaginal IgA (p = 0.015) (Figure 2C and D).Specific IgG subclass analysis demonstrated that TT when given alone induced a balanced systemic IgG1/IgG2a ratio of 0.9 (Figure S1B) and this was maintained with all adjuvants except chitosan which gave a significantly increased IgG1/IgG2a ratio relative to TT alone.Nasal immunisation with gp140 and TTThe administration of gp140 alone via the nasal route induced barely detectable systemic or local IgG and IgA responses. However, all adjuvant candidates tested promoted strong systemic IgG production, giving titres up to 5.336105 (p,0.01) (Figure 3A). Likewise, specific serum IgA titres were induced by all adjuvant candidates with serum titres of up to 3.46104. These were significant for all adjuvants (Figure 3B), however the effect of R848 was significantly lower than that of the other adjuvants for both IgG and IgA (p = 0.01). In vaginal wash samples, all adjuvants significantly increased specific IgG titres (p,0.01), which were below or at the cut-off for detection when gp140 was given alone. FSL-1 and R848 also augmented vaginal IgG responses but to a lesser extent (Figure 3C). For specific IgA, all the candidates significantly increased vaginal antibody titres but the enhancement mediated by R848 was significantly lower than that of the other adjuvants (Figure 3D). IgG subclass analysis indicated that all candidates tested significantly increased both specific IgG1 and, with the exception of chitosan, IgG2a antibody titres (p,0.01) (data not shown). gp140 when administered alone gave an IgG1/IgG2a ratio of 3.5. FSL-1, MPLA, Pam3CSK4 and chitosan increased IgG1/IgG2a ratios promoting a Th2 biasing of responses that were significant for Pam3CSK4 and Chitosan. Conversely, poly I:C and CpG-BFigure 1. Sublingual immunisation with gp140. Endpoint titres for IgG (A, C) and IgA (B, D) in sera (upper panels) and vaginal washes (lower panels) from animals immunised three times with gp140 sublingually. Asterisks indicate significant differences 
between the different adjuvant/ antigen groups and the PBS control group. doi:10.1371/journal.pone.0050529.gMucosal TLR Adjuvants for HIV-gpFigure 2. Sublingual immunisation with Tetanus toxoid. Endpoint titres for IgG (A, C) and IgA (B, D) in sera (upper panels) and vaginal washes (lower panels) from animals immunised three times with Tetanus toxoid sublingually. Asterisks indicate significant differences between the different adjuvant/antigen groups and the PBS control group. doi:10.1371/journal.pone.0050529.gFigure 3. Intranasal immunisation with gp140. Endpoint titres for IgG (A, C) and IgA (B, D) in sera (upper panels) and vaginal wash.