Study of the Effects of Nanoparticles in the Antigen-Presentation Mechanism

Zhicheng Wei (1) and LUPITA D. MONTOYA (2)

(1) Rensselaer Polytechnic Institute, Troy NY; (2) University of Colorado at Boulder

     Abstract Number: 265
     Last modified: November 9, 2009

Abstract
The possible health effects of nanoparticles (NPs) are increasingly becoming a concern as they are being used more ubiquitously; however, very little is known about the possible effects NP may have on the human immune system. Macrophages (MØ) are key phagocytic cells in the immune system, which can both scavenge foreign particulate matter as well as process and present foreign antigens to CD4+ T cells to elicit T cell help. In preliminary studies, antigen-pulsed resting or IFN-g-activated bone marrow-derived MØ (BMMØ) were co-cultured with CD4 T cells and resultant IL-2 and IL-5 cytokine production determined by cytometric bead array (CBA). Results showed that the presence of NP in an antigen presentation environment affects the subsequent production of T-cell cytokines like interleukins 2 and 5 (IL-2 and IL-5).
This study seeks to further research this effect by determining the mechanism by which NP may impact antigen presentation. In particular, this study focuses on the impact of various NPs (TiO2, Al2O3 and SiO2) of different sizes (5, 50, 200 nm) on the ability of MØ to process or present antigens to T cells. It is hypothesized that changes on IL-2 and IL-5 production could occur either because NPs cause MØ to release a soluble factor that alters T-cell cytokine production or because NPs have a direct effect on MØ altering the way of presenting antigen and altering T-cell cytokine production.