Edward A Botchwey, PhD
Department of Biomedical Engineering
Georgia Institute of Technology
Cell Manufacturing and Lipidomics
Our long-term objective is to develop processes to maintain and enhance the therapeutic potency of biomanufactured MSCs based on modulation of sphingolipid (SL) metabolism. SLs are a highly diverse family of molecules which are important building blocks of eukaryotic membranes. We apply state of the art RNA sequencing (RNA-seq) combined with mass-spectrometry-based lipidomics to investigate how changes in SL network metabolism regulate immune modulatory functions of cultured human MSCs (see Awojoodu et al. Blood 2014). I also perform high throughput liquid chromatography-mass spectrometry (LC-MS) lipidomics experiments and assessments of MSC osteogenic capacity and immune modulatory potency. We apply LC-MS analysis (see Ogle et al. Acta Biomat 2014) to determine whether variation of in vivo potency is accompanied by significant changes in production of bioactive signaling SLs and subspecies selective-changes of acyl chains in complex SLs . We use multi-variate analysis of lipidomic network profiles will yield mechanistic insight into the origin of observed changes in bioactive SL concentrations. This analysis highlights the particular reactions in the SL metabolic network that may be targeted to prevent reductions in immune modulatory potency during culture and expansion. We employ pathways analysis to investigate whether the SLs, fatty acid elongation and differential concentrations will be correlated with osteogenic capacity.
We investigate traumatic injuries resulting from ischemic damage, nerve transection injuries, or volumetric defects in bone and soft tissues. Because surgical reconstruction can lead to extensive morbidity, we are particularly interested in treatments to prevent disorganized tissue remodeling, gradual fatty/fibrous degeneration and chronic strength deficits. As the sequelae of traumatic injuries increase at a disproportionate rate with advancing age, we study how to restore endogenous tissue healing capacity in aged animal models. We seek to understand the microenvironmental factors that govern healing outcomes in musculoskeletal tissues and skin in order to harness endogenous mechanisms of repair. Efficient wound healing requires the angiogenic and fibrogenic activity of macrophages, which are derived at least in part from circulating monocytes that undergo differentiation post-extravasation. We focus specifically on unlocking the therapeutic potential of pro-regenerative monocyte subsets and their progeny. We are specifically investigating how transient immuno-regulation using targeted agonists/antagonists of S1P receptors can be exploited control trafficking of host stem cells, enhance tissue vascularization, and resolve inflammation. We also combine approaches in medicinal chemistry and biomaterials science to develop strategies for delivery of naturally occurring and biomimetic small molecule therapeutics.