PROJECT SUMMARY
The immunogenicity of nanomaterials is directly related to their performance and toxicity. However, there is still
a lack of systematic studies of how nanomaterials interact with the immune system. In this work, we will focus
on the immunogenicity of lipid nanoparticles (LNPs). Various studies have raised concerns about the adverse
event of LNPs from PEG lipids, ionizable lipids, and even helper phospholipids, such as anti-polyethylene glycol
(PEG) antibodies found in BioNTech/Pfizer and Moderna COVID vaccines. During our recent studies of LNP-
based mRNA cancer vaccines, the side effects, including ulcerative dermatitis, were also found on vaccinated
mice after subcutaneous administrations. Most studies of LNPs via screening or design today have mainly
focused on LNP efficacy while few on LNP immunogenicity. Very limited human data on very limited formulations
in the context of COVID-19 vaccines following intramuscular administration have very limited scope in
immunogenicity such as accessing the overall outcome of immunogenicity only. The investigations have not
extensively delved into the underlying causes of the widely reported adverse effects associated with LNP-based
mRNA vaccines, the specific immunological pathways of immunogenicity, and the underlying relationship
between immunogenicity and components of LNPs. Currently, the mechanism of how LNPs induce adverse
events is yet to be fully understood. Here we will formulate three libraries of LNPs covering widely used lipids
and vary chemical properties of each component. We will perform immunological assays on primary murine cells
to evaluate cytokine secretion and profile inducible gene expression. Similar tests will be performed in human
peripheral blood mononuclear cells (hPBMCs). Toll-like receptor (TLR) and NOD-like receptor (NLR)-dependent
immune response will be evaluated by reporter assays and validated in deficient mouse primary cells.
Furthermore, the immunogenicity of LNPs will be profiled in the setting of intramuscular injections by assessing
local inflammatory responses at the injection sites, and intravenous injections by evaluating the systemic
response including accelerated blood clearance effects. Through these studies, we will identify key components
that are responsible for LNP immunogenicity, understand how the chemistry of each LNP component alters the
level of immune activation, and discover any synergistic effects on the immunogenicity among the components.
The success of this work will advance current LNP technologies and provide clinical benefits for applications
from vaccines to therapeutics.