Local immunometabolism modulating biomaterials for immunosuppressive applications

Abstract
Biomaterials-based strategies to modulate the immune responses has generated tremendous interest in the
past decade. Notably, biomaterials can not only be used for delivering drugs (synthetic or biologics) but by
themselves can modulate the function of different cells. Recently, we have demonstrated that the metabolite
alpha-ketoglutarate (aKG) can be polymerized, and these polymers by themselves are able to suppress
activation of dendritic cells (DCs – forms the bridge between innate and adaptive immune system).
Interestingly, our preliminary data also demonstrates that delivery of PFK15, an inhibitor of PFKFB3 enzyme (a
key step in glycolysis) downregulates CD86 (co-stimulatory molecule) but maintains MHC-II (stimulatory
antigen presenting molecules) on DCs. Notably, glycolysis can control the function of activated DCs.
Therefore, glycolysis-inhibition mediated prevention of DC activation and simultaneous antigen expression, can
lead to antigen-specific immunosuppression responses. However, systemic inhibition of glycolysis has
inherent toxicity (clinical trials) associated with it, and have regulatory hurdles for clinical use. Therefore, the
main goal of this R01 program is to develop drug delivery vehicles that can deliver glycolysis inhibitors and
antigens locally to DCs, which will then systemically suppress inflammation. The central hypothesis of this
proposal is that co-delivery of antigen and glycolytic inhibitor will induce DC tolerance and generate peripheral
antigen-specific suppressive T-cells, which will then promote reversal of tissue inflammation. This strategy will
be tested in a rheumatoid arthritis animal model. This hypothesis will be tested by performing experiments in
the following aims: AIM 1: Test if paKG formulations can generate long-term remission of RA by maintaining
metabolic homeostasis in joint tissues. AIM 2: Determine the effect of paKG formulations on cells associated
with arthritic tissue. AIM 3: Test the ability of paKG formulations to prevent progression of RA in K/BxN mice
AIM 4: Develop scaled paKG formulations for safety/toxicity profiles. This research will be an important
foundation in the development of technologies based on metabolic modulation of immune cells for autoimmune
disorder treatment. The results from this project will generate a sustained release platform, which after
application can prevent the progression of RA, or even reverse the damage.

Grant Number: 5R01AR078343-05
NIH Institute/Center: NIH
Principal Investigator: Abhinav Acharya