In more recent research conducted at the Weizmann Institute, Krizhanovsky uncovered the molecular mechanisms that underlie the clearance of senescent cells. He identified the receptors on their surface that help their identification by the NK cells; in addition, he found that the NKs kill the senescent cells by releasing a protein that perforates cellular membranes and lets a killer protein get into the cell.
With the help of drugs based on these mechanisms, it may be possible in the future to prevent fibrosis of the liver or other organs, or to treat aging-related diseases, such as certain forms of arthritis or atherosclerosis, in which senescent cells are involved. The drugs will help remove senescent cells that the body is not clearing properly.
Such drugs may also help prevent cancer. In the past few years, scientists have shown that cellular senescence is one of the body’s natural mechanisms for blocking cancer in its early stages. That is probably the reason many precancerous growths, such as moles that with time might turn into melanoma, contain a large proportion of senescent cells. An efficient removal of these cells from the body may help avert the transformation of precancerous lesions into full-blown cancer.
And in a more distant future, it may even be possible to remove senescent cells from tissues to delay aging and promote health over the years.
From Embryos to Aging Cells
During his doctoral research at the Hebrew University of Jerusalem, Dr. Valery Krizhanovsky studied the fate of cells in embryonic development. But his interest in cellular fate in more general terms ultimately led him to the other extreme of the cellular lifespan: senescence.
Krizhanovsky, born in Ukraine, had begun his studies at the University of Kursk in Russia, in the faculty of pharmacology. When he immigrated to Israel with his parents in 1991, he continued his studies at the Hebrew University. Starting in 2005, he went on to conduct postdoctoral research at Cold Spring Harbor Laboratory in New York, before joining the faculty of the Weizmann Institute in 2010.
Krizhanovsky lives in Rehovot with his wife Regina and their two daughters, Maya and Mika. In his spare time, he enjoys reading, particularly on theories and the psychology of economics.