In a study published in Nature Methods from the Nature group, Prof. Kellogg, Dr. Oded Ravavi, Dr. Itamar Goldstein and other researchers from Tel Aviv University and from around the world show the method that allows to identify the communication of cancer cells with the cells of the immune system, to fight in cells infected with viruses and more
Every cell in our body has the same DNA, but only some of the genes in it produce the proteins necessary for the functioning of that cell (and only some of the proteins common to all body cells). One of the problems faced by biologists and biochemists trying to understand what substances pass from cell to cell during intercellular communication (for example, in the scanning of a cancer cell by the cells of the immune system), is that it is not always possible to identify proteins in a cell that it did not produce but that other cells reached it.
Now a group of researchers led by Prof. Yoel Kellogg and Dr. Oded Rafi from the Department of Neurobiology in the Faculty of Life Sciences at Tel Aviv University is reporting on a method that will allow these proteins to be identified. The study was recently published in the journal Nature Methods from the group of the prestigious journal Nature which deals with basic methods for research in the field of life sciences.
The applications of the new method are many, one of the possible directions is to use the method to understand which proteins move from the cells of the immune system to other cells in the body and vice versa, thereby promoting, among other things, the understanding of mechanisms that cause cancer.
The research is part of the doctoral thesis of Oded Ravavi, currently a postdoctoral fellow at Columbia University in New York and then a doctoral student in the laboratory of Professor Yoel Kellogg at Tel Aviv University. The study was conducted in collaboration with Dr. Itamar Goldstein at the Sheba Hospital Cancer Center and Dr. Leonard Foster at the University of British Columbia in Vancouver, Canada.
"In the article in Nature Methods, we demonstrate in two ways how proteins move from cell to cell. We tested cells of the immune system that stick to another cell to check it and see, among other things, whether it is cancerous, we see that the cell that was scanned transfers hundreds of proteins to the cell of the immune system that were not Their ability to move between cells is known before.
"Since it is the same DNA, and we find the same protein in two different types of cells belonging to the same body, we were required to invent a method that would differentiate between "local" proteins and "foreign" proteins. To do this, we grew the cells on different growth media. We let one cell 'eat' acids Aminos are natural, and because of this all its proteins were composed of normal amino acids. We 'fed' the second cell with amino acids that we changed so that the atoms They will contain excess neutrons and therefore all the proteins that this cell produces will be a little heavier. Although this is a very small difference, it can be detected using extremely sensitive devices. After that, we made contact with each other. At the end of the process, we used specific cell isolation technologies Only one type of cell and we checked the composition of its proteins - which of the proteins are 'normal' and which are 'heavy'. This is how we were able to identify the origin of each protein."
