Fig. 5: Intranasal vaccination with RBD-fused engineered HSA induces antibodies solely toward the subunit vaccine antigen. | Nature Communications

Fig. 5: Intranasal vaccination with RBD-fused engineered HSA induces antibodies solely toward the subunit vaccine antigen.

From: An intranasal subunit vaccine induces protective systemic and mucosal antibody immunity against respiratory viruses in mouse models

Fig. 5

a Illustration of the RBD-fused albumin with CpG site-specifically conjugated to cysteine 34 (C34) in domain I of albumin, distal from the principal FcRn binding site. b RBD-specific IgG and IgA in sera, BALF, nose, and saliva at endpoint after intranasal vaccination of female Tg32-hFc mice (prime dose: 20.0 μg RBD-QMP with or without 20 μg CpG, 21.4 μg CpG-RBD-QMP, or PBS). c Percentage antigen-specific B-cells in mediastinal lymph nodes. d Illustration of ELISA for detection of antibodies against human albumin (HSA) after vaccination, and HSA-specific antibodies generated at endpoint after intranasal prime and boost with QMP-containing albumin detected using human IgG. e Illustration of the HSA/hFcRn mouse model expressing human FcRn and HSA. Immune responses at endpoint after intranasal vaccination of female mice (prime dose: 6.2 μg RBD, 20.0 μg RBD-WT and 20.0 μg RBD-QMP in combination with 20 μg CpG) displaying f RBD-specific IgG and IgA antibodies in sera and BALF, respectively, and g HSA-specific mouse IgG antibodies in sera. Serology was detected using FCBA (b and f) or ELISA (d and g). Bars indicating group mean ± SD with individual mice represented as a single datapoint (except d) and curve plots presented as biological mean per group ± SD. b, d, f, g n = 6, except RBD-QMP n = 5. c All mediastinal lymph nodes per group n = 6, except RBD-QMP n = 5 were merged and samples prepared in technical triplicate for flow cytometry. b and f One-way ANOVA with Tukey’s multiple comparison. a and e Created or b, d, f, g partially created in BioRender86.

Back to article page