Abstract:
The homing of Hematopoietic Stem/Progenitor Cells (HSPC) is an important biological phenomenon. It is a multi-step process that delivers cells into their niche (bone marrow) to establish the production of various blood cell types after bone marrow transplantation therapy. This phenomenon has been extensively studied to expand our understanding of the homing mechanism that will have an impact on Hematopoietic Stem Cell (HSC) therapy. In addition, this phenomenon facilitates the widespread of a metastatic type of cancer into different organs. The homing step is initiated in the vascular system, where circulating cells must first come in contact with the endothelial cells, which occurs against the shear stress exerted by blood flow. Tethering of HSPCs to endothelium is mediated by spatiotemporally organized ligand-receptor interaction of ligands expressed on HSPCs to their receptors “selectins” on endothelial cells. Many research studies that used in-vitro approaches adopted various high-resolution imaging techniques for direct visualization of subcellular structures and analyzed their dynamics. However, characterizing the nanoscopic spatiotemporal interactions and migration patterns of a rolling cell on an endothelium cell layer remains little known and challenging. Our research study provides new insight into characterizing homing mechanisms using microfluidics-based advanced imaging techniques. Specifically, it enables imaging of stem cell-intrinsic spatiotemporal details at the nanoscale level while homing on an endothelial layer under external shear stress. Thus, it will simulate a closer picture of what happens under physiologically relevant conditions and will contribute a step further in understanding stem cell behavior during homing and transmigration.

Bio:
Abdullah Alghamdi is a PhD candidate at the King Abdullah University of Science and Technology (KAUST) under Prof. Satoshi Habuchi’s supervision. His research focuses on investigating the bio-molecular aspect of the cancer cells to understand the mechanisms playing a key role in tumor development while keeping a commitment to fulfilling the transitional promise of developing novel cancer therapies. He is currently exploring the process by which immune and stem cells move in the circulatory system and home at their targeted sites within the human body by using a multidisciplinary approach that combines biochemical, biophysical, and imaging techniques.