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TRACK 4 TRACK 4 Technical Program

NF-kappaB activation in individual murine CH12.LX B cells was observed to 10:00am Assessment of Exploiting Protein Corona for Active
vary inversely with respect to the ligand linker length suggesting that signal Targeting of Nanoparticles to Desired Cells
strength may depend on local flexibility of the receptor-ligand complex,
which likely mediates the force transmitted between the two molecules. To- Technical Presentation. NEMB2016-6115
gether, these findings suggest that strength of intracellular signal induction
depends on the local mechanical environment, which may provide a means
to tune signal strength by employing nanostructures assembled by DNA ori- Vahid Mirshafiee, Raehyun Kim, University of Illinois at Urba-
gami. Our device could inspire novel designs used to study multiple intracel- na-Champaign, Urbana, IL, United States, Soyun Park, University
lular signaling pathways in a variety of biological systems as well as enhance of California, Berkeley, Berkeley, CA, United States, Morteza Mah-
efficacy of antibody-mediated therapeutics. Funded in part by start-up funds moudi, Stanford University School of Medicine, Stanford, CA, Unit-
provided to Dr. Castro by the Department of Mechanical and Aerospace En- ed States, Mary Kraft, University of Illinois at Urbana-Champaign,
gineering at The Ohio State University and in part by a Specialized Center of Urbana, IL, United States
Research from the Leukemia and Lymphoma Society, P50-CA140158.

Upon exposure of nanoparticles (NPs) to the physiological environments,
proteins and other biomolecules adsorb onto the nanoparticles’ surfaces,
TUESDAY, FEBRUARY, 23 and form a biomolecule layer, known as the “protein corona.” Previous stud-
ies have shown that this biomolecule corona could significantly reduce the
NPs’ targeting efficiency. Here, we investigated whether the NP’s surface
4-5 could be engineered to promote the binding of proteins that have natural
NANO-DESIGN CONCEPTS targeting capabilities, thereby forming a functional protein corona that could
be utilized for actively targeting NPs to the desired cells. We selected the
well-established opsonin-mediated phagocytosis of NPs as a simple model
Hidalgo 9:30am - 11:00am system to test the feasibility of this strategy. In order to promote binding
of opsonins to the NPs upon exposure to the plasma proteins, NPs were
first pre-coated with gamma-globulins, followed by incubation with human
Session Organizer: Ashutosh Agrawal, University of Houston, plasma for protein corona formation. Analysis of protein corona composition
Houston, TX, United States
indicated that the protein corona of gamma-globulin pre-coated NPs was
enriched with opsonins. Nonetheless, cellular uptake studies showed no
9:30am Meeting the Challenges of Adoptive Cell Immunothera- significant difference in the uptake of pre-coated and uncoated NPs that had
py with Protein Nanorings been exposed to human plasma by macrophages. Furthermore, our studies
indicated the opsonins in the protein corona of pre-coated NPs were unable
Keynote. NEMB2016-6153 to interact with their binding partners, most likely because these opsonins
were blocked by other plasma proteins in the corona. Thus, our study shows
Carston Wagner, University of Minnesota, Minneapolis, MN, United that the protein corona not only needs to be enriched with proteins that
have natural targeting abilities, but their spatial orientations and availabilities
States must also be controlled in order to utilize them for active NP targeting.

The recent development of chimeric antigen receptors (CARs) T-cells is one 10:20am Delineating the cellular uptake properties and intra-
of the most exciting recent developments in anti-cancer therapy research.
Typically, T-cells from a cancer patient are genetically engineered to express cellular Trafficking Pathway of Targeted Nanorods of Defined
a single chain antibody (scFv)-CD3 fusion protein that can target a cancer Aspect Ratios
cell surface biomarker. After re-introduction into the patient, CAR-expressing
T-cells selectively eliminate the target cancer cells. While successful, the Technical Presentation. NEMB2016-6152
genetic engineering of cell surfaces is time consuming and irreversible.
Furthermore, because there are no general non-invasive methods for mon- C.H. Jonathan Choi, The Chinese University of Hong Kong, Shat-
itoring the movement and location of modified T-cells in vivo, it is difficult to in,Hong Kong
correlate the therapeutic effect of CAR T-cells with their biodistribution.
The past decade has witnessed more investigations into the application of
Our group has shown that two dihydrofolate reductase molecules (DHFR2) anisotropic nanoparticles as intracellular delivery carriers of therapeutic and
fused to single chain antibodies (scFv) or peptides can be engineered to imaging agents, yet their “bio-nano” interactions with the cell remain poorly
spontaneously self-assemble upon the addition of the chemical dimerizer, elucidated.
bis-methotrexate (BisMTX), into either highly stable octavalent chemically
self-assembled nanorings (CSANs). CSANs have been prepared with BisMTX In this work, we will systematically explore the effect of nanoparticle geom-
containing a third arm, thus enabling it to be conjugated to oligonucleotides, etry on the mechanism for cellular uptake as well as the pathway of intra-
fluorophores, radiolabels and drugs. Recently, we have prepared bispecific cellular trafficking of anisotropic nanoparticles. For our model nanoparticle
anti-CD3 CSANs that are capable of simultaneously targeting a cancer an- system, we have chosen gold nanorods due to their easily tunable aspect
tigen and the pan T-cell antigen, CD3. The bispecific CSANs rapidly (min) ratios. Coating gold nanorods with poly(ethylene glycol) (PEG) chains on
and stably (days) bind to CD3 on T-cell membranes, thus forming chemically their surface renders them biocompatible with living cells, supporting our
self-assembled prosthetic antigen receptor (PAR) T-cells. Upon incubation of subsequent analysis of their “bio-nano” interactions solely based on aspect
the PAR T-cells with antigen positive cancer cells, rapid and selective cell kill- ratio. To ascertain whether these geometry-based conclusions will still hold
ing was observed. A unique feature of our approach is the ability to remove in the context of cellular targeting, we have also prepared gold nanorods
the CSANs from the T-cells by incubation with the FDA-approved non-toxic that are surface-modified with DNA oligonucleotides, noting that, by litera-
antibiotic trimethoprim at clinically relevant concentrations, thus allowing us ture precedent, three-dimensional DNA nanostructures can naturally target
to deactivate the cells pharmacologically. In addition, we have demonstrated Class A scavenger receptors (SR-A) on the cell surface. By tracking how
that the CSANs can be site specifically radiolabeled and used to prepare PEG-coated or DNA-coated gold nanorods interact with C166 cells (mouse
radiolabeled PAR T-cells enabling our ability to track the cells in vivo by PET/ endothelial cells with an appreciable expression level of SR-A), we will ad-
CT. We have also demonstrated that targeted radiolabeled CSANs can be dress two questions. (1) How do aspect ratio and receptor-mediated target-
used to image tumors. This lecture will discuss these and recent results of ing collectively dictate the uptake of nanorods by the cell? (2) How do both
our application of nanotechnology to provide a non-genetic and reversible parameters influence the movement of nanorods inside the cell? 53
method for the monitoring and preparation of targeted T-cells that can be ap-
plied to the clinical development of anti-cancer immunotherapy.