Discipline: Nanoscience
Subcategory: Biomedical Engineering
Session: 1
Chinwendu Chukwu - Rutgers University
Co-Author(s): Randall Toy, Georgia Institute of Technology, Atlanta, GA; Krishnendu Roy, Georgia Institute of Technology, Atlanta, GA
Cell therapies involving genetically engineered antigen-specific T cells exhibit curative properties for cancer and other chronic diseases. The efficacy of these therapies depends upon efficient transduction and expansion of the T cells. Because antigen-presenting dendritic cells (DCs) play a major role in stimulating T cell expansion, strategies to modify the adeptness of antigen presentation to DCs may enhance T cell potency. Thus, the use of adjuvants to stimulate in-vivo antigen-presentation to DCs is critical in inducing strong T cell-mediated responses. However, delivery of soluble adjuvants causes systemic toxicity due to their widespread biodistribution. Therefore, utilizing polymeric nanoparticles as an adjuvant delivery system may guide adjuvant release to target areas, thus inducing local antigen presentation. A nanoparticle-adjuvant delivery system was designed in which the adjuvants are “loaded” onto the surface of the nanoparticles. The formulation of the loaded nanoparticles may affect how well the adjuvants stimulate antigen presentation to immune cells. To study these effects, the following procedures were performed; 1) characterization of the loaded nanoparticles, and 2) treatment of immune cells with the loaded nanoparticles. The nanoparticles were first loaded with different doses and combinations of adjuvants and further characterized through measurement of their size, surface charge, and the amount of adjuvant loaded onto the nanoparticles. Consistency in the surface charge of the nanoparticles was observed, averaging around +20 mV, but particle size increased, ranging from 350 nm to over 600 nm, due to loading-induced aggregation of the nanoparticles. 100% loading of adjuvants was measured onto the surface of the nanoparticles, which allows us to conclude an overall successful loading process. We then activated human peripheral blood mononuclear cells (PBMCs), which contain DC and T cell subsets, by treating them with the adjuvant-loaded nanoparticles. The cells’ subsequent protein secretion levels were quantified through a Luminex assay. High secretion levels of the IL-1β, IFN-α, & TNF-α proteins were measured from PBMCs treated with nanoparticles with the adjuvant PUUC. Based on these preliminary results, we predict that the PUUC adjuvant-nanoparticle formulations may play a substantial role in assisting antigen presentation to immune cells. Future research includes treating sorted DC and T cells with the adjuvanted nanoparticles to decipher the effects of the adjuvanted nanoparticles specific to those subsets. References: Sallusto F, Lanzavecchia A. The instructive role of dendritic cells on T-cell responses. Arthritis Research. 2002;4(Suppl 3):S127-S132. doi:10.1186/ar567. Petrovsky, N. and Aguilar, J. C. (2004), Vaccine adjuvants: Current state and future trends. Immunol Cell Biol, 82: 488-496. Sadelain M, Rivière I, Riddell S. Therapeutic T cell engineering. Nature. 2017;545(7655):423-431. doi:10.1038/nature22395.
Funder Acknowledgement(s): I would like to thank Dr. Krishnendu Roy, Randall Toy, and the Roy Lab team for accepting me into their lab. I also thank Aaron Levine and Lakeita Servance, as well as Dr. Tia Jackson, for facilitating the research program. Funding was provided by an NSF grant to the CMAT REU program.
Faculty Advisor: Krishnendu Roy, krish.roy@gatech.edu
Role: I took part in both phases of my research project. For the first phase, I loaded the adjuvants onto the nanoparticles by following a protocol for adjuvant loading. After the nanoparticles were loaded, I was then tasked with measuring the size and zeta potential of the nanoparticles, which I was able to do on a ZetaSizer software. I also measured the amount of adjuvant that loaded onto the nanoparticles by using a plate reader. After loading several nanoparticle samples, I chose certain adjuvant-nanoparticle formulations to feed to the immune cells and conducted a Luminex assay with the activated cells. I then gathered and analyzed the data from the assay to draw conclusions. All of this was done through the mentorship of my research advisor, who facilitated my research project.