Testing the effect of liver transplantation on cell mortality from different tissues using methylation patterns in free cfDNA from cells in the blood Supervisor: Netanel Loepfer Laboratory: Prof. Tommy Kaplan

DNA methylation is a biochemical process which effects gene expression. In each cell type in the body there are different genes that are expressed, hence, each cell type is characterized by some methylated genes (meaning methylation occurs in them) and some un-methylated genes. As a result, the source of different DNA fragments can be identified, and among those, DNA fragments from dead cells that have been excreted into the blood flow. Using this, there is a growing concept in the field of bioinformatics and computational biology of analyzing the methylation of cell-free DNA found in the blood samples of various patients known to be at a certain risk and also as a routine test, to monitor cell death in their body as a way of detecting diseases.

In this research I have created tools which allowed me to explore the changes in cell deaths from different tissues in liver transplantation (LT) patients pre and post transplantation. My research was based on analysis of DNA methylation of cell-free DNA from blood samples collected from LT patients. I have found that the amount of hepatocyte (liver cells) deaths rises significantly post transplantation, as, safe to assume, do deaths of various immune system cell types. In the future, it is plausible to assume that similar research on a larger number of samples will contribute to the treatment of LT patients in general and transplant rejection cases in particular.