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.