FIGURES
Figure 1. Model illustrating the impact of IgG antibodies on Type I hypersensitivity . Allergens are taken up by antigen presenting cell which present processed antigen to TH cells. TH cells help B cells to produce IgE which binds to FcεRI on the surface of mast cell and sensitize them. Allergen-specific IgG antibodies neutralize allergens and/or engage the inhibitory receptor FcγRIIb thereby agonist mast cell activation.
Figure 2. Strength of interaction between antibody and antigen. A) Difference between antibody affinity and avidity. B-C) Lateral movement at 37°C facilitates multivalent and high-avidity binding of IgE antibodies to allergens, while temperatures below the Krafft point at (e.g. 4°C) inhibit lateral movement and multivalent binding.
Figure 3. The RNA dependency of VLP Peanut to induce high-avidity antibodies and to drive antibody class switching. A) Illustration of VLP Peanut (PDB file). VLP Peanut consists of CuMV-derived subunits (PDB code 1F15) and CuMV subunits that were modified by the incorporation of Ara h 2 (PDB code 3OB4). For the illustration, the Ara h 2 monomer was manually placed near the insertion loop present in the CuMV subunit by using COOT. Based on the obtained modified PDB file and icosahedral symmetry operators the image was created in pymol. The figure was curtosy of Prof Kaspars Tars, Riga B) Cartoon representation of VLP Peanut encapsulated RNA. C) Ara h 2 specific total IgG responses are highly dependent on the VLP Peanut-carried RNA. Illustrations depicted in B and C created with Biorender.com.
Figure 4. A cartoon illustrating a VLP nanoparticle-based vaccine against peanut allergy. The nanoparticles are packed with ssRNA, a TLR7/8 ligand, and display Ara h2 antigen. The natural pentameric IgM antibody can bind the VLPs with low affinity/high avidity. Such interaction contributes to the activation of classical complement cascade and binding of the formed immune-complex on FDCs for effective formation of GCs. This vaccine may induce high-affinity antibodies, drive antibody class-switching and establish long-lived memory. Abs; antibodies.