Dr. Yehudit Bergman
Hadassah Medical School
My research focuses on epigenetics — changes in gene activity governed by influences outside the genes themselves. WI e focus on two major topics: the role of epigenetics in the development of the immune system, and its involvement in stem cells, inflammation and cancer.
To prevent damage caused by stress and pathogens, the lymphocytes in our bodies generate a huge diversity of antibodies. Every single lymphocyte makes one specific antibody and each antibody is designed to attack and neutralize a specific intruder. My research team at the Hebrew University Medical School introduced new perspectives in our understanding of the molecular mechanisms that underlie the ability of each lymphocyte to generate a single type of antibody, a mechanism, termed allelic exclusion, which prevents chaos in the immune system. This is a cornerstone in immunology. We have shown that epigenetics plays a major role in this process, making one chromosome more accessible to the machineries needed for gene expression. Further understanding would potentially clarify the causes of autoimmune diseases and pave the way to their treatment.
Our laboratory has also made major contributions on the epigenetic regulation of embryonic stem cells.
At its initial stage, the embryo grows as the stem cells comprising it divide and multiply. At a given stage of the embryo's development, the genes that tell a stem cell to divide into daughter stem cells are silenced, and other genes are activated that tell different groups of embryonic stem cells to become specialized tissues of the body. This is called the epigenetic regulation of embryonic stem cells, which is yet another focus of my team's research effort. This silencing mechanism represents the major barrier to embryonic reprogramming and a key mechanism in cancer formation. Since this mechanism is characteristic of many types of tumors, studying it would potentially lead to a better understanding of cancer, and hopefully, to a treatment across a wide spectrum of cancers.
To summarize: my career has always focused on developmental programming both in the immune system and during early embryogenesis. It is this combination that led me to connect between cell-fate decisions made in embryonic cells and those involved in the hematopoietic system in order to help decipher the mechanisms that contribute to generation of the immune repertoire, carcinogenesis, reprogramming and more recently regeneration.