Oral administration of chitosan/DNA nanoparticles containing DNA coding for FVIII and FC IgG fragment or IL-10 for the modulation of immune responses to FVIII in hemophilia mice
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Date
2016
Authors
Yerkesh, Zhadyra
Journal Title
Journal ISSN
Volume Title
Publisher
Nazarbayev University School of Science and Technology
Abstract
Hemophilia A is an X-linked bleeding disorder, which occurs due to deficiency of
clotting protein FVIII. Current treatment involves regular lifelong infusion of
recombinant or plasma-derived FVIII protein, which is suboptimal, invasive and very
expensive. One of the biggest challenges of the current therapy is the recognition of
FVIII by immune system as a foreign substance, leading to the development of
neutralizing antibodies, which makes further administration of FVIII ineffective.
Therefore, an alternative cost effective and safe treatment to Hemophilia A is highly
desirable. We propose chitosan-mediated oral non-viral gene therapy as a safe and costeffective
strategy for immune modulation in severe hemophilia A cases. Having a
strong affinity for DNA and forming nanoparticles, chitosan-DNA complexes protect
plasmid DNA fi-om degradation by the low pH envu-onment of the stomach and from
nucleases in the GI tract; further, safe re-administration of nanoparticles is possible. We
also propose to include in the plasmid DNA coding for the Fc fragment of IgG heavy
chain region, which contains Tregitope sequences, T cell epitopes that specifically
activate regulatory T cells or anti-inflammatory cytokine IL-10 that may modulate the
immune response against FVIII protein. Therefore, it is hypothesized that orally
administered chitosan/DNA nanoparticles will lead to clinically relevant amount of
FVIII in the host without an immune response, providing long term, cost-effective and
safe treatment for hemophilia A.
For this study we aimed to: I) optimize nanoparticles in terms of effective gene
expression in vitro; 2) treat hemophilic mice orally with chitosan nanoparticles
containing DNA coding for FVIII and for immunomodulatory elements (Fc fragment of
IgG and IL-10) to induce tolerance to FVIII. We found that the key factors contributing
to the effectiveness of gene expression in chitosan/DNA nanoparticles are the type of
chitosan, the charge ratio (N/P) and the DNA concentration. In vivo, the optimized
nanoparticles containing FVIII+Fc DNA significantly decreased antibody formation
specific to F V I I I in prophylactic group of mice, and in 4/6 mice receiving nanoparticles
containing FVIII+IL-10. It is tempting to hypothesize that this strategy might also be
extended to modulate immune responses to other antigens.
Description
Keywords
Hemophilia A, FVIII, DNA
Citation
Zhadyra Yerkesh. 2016. Oral administration of chitosan/DNA nanoparticles containing DNA coding for FVIII and FC IgG fragment or IL-10 for the modulation of immune responses to FVIII in hemophilia mice. Nazarbayev University. School of Science and Technology