Researchers at the University of Illinois have devised a novel imaging technique called spatial light interference microscopy (SLIM) that utilizes two light beams to quantify cell mass.
The fully non-invasive method, SLIM allows the researchers to investigate cells when they perform their usual functions. It utilizes white light and can be coupled with additional conventional microscopy technologies, such as fluorescence, to study cell growth.
SLIM-imaged cell. Credit: Quantitative Light Imaging Laboratory
The SLIM technique, a combination of holography and phase-contrast microscopy, can resolve the issue of whether cells develop exponentially or at a constant rate. This highly sensitive technique measures cells mass with femtogram precision. It can quantify a single cell growth as well as mass transport inside the cell.
The high sensitivity of the SLIM technique enables the researchers to observe cell growth at various cell cycle phases. They observed that mammalian cells grow exponentially only during the cell cycle’s G2 phase, before the cell divides and after the DNA reproduces. This finding is important not only for fundamental biology but also for tissue engineering, drug development and diagnostics.
The researchers plan to utilize the new information on cell growth to various disease models. They intend to utilize the SLIM technique to measure the growth rate between cancer cells and normal cells as well as the impact of curing methods on the growth rate.
Gabriel Popescu, who led the development of the SLIM technique, is launching SLIM as a common resource in the University of Illinois campus, expecting to exploit its versatility for fundamental and clinical research in various fields.