Imaging of dense cell cultures by multiwavelength lens‐free video microscopy

Abstract

They present results for lens-free microscopy for the imaging of dense cell culture. With this aim, they use a multiwavelength LED illumination with well separated wavelengths, together with the implementation of an appropriate holographic reconstruction algorithm. This allows for a fast and efficient reconstruction of the phase image of densely packed cells (up to 700 cells/mm ) over a large field of view of 29.4 mm . Combined with the compactness of the system which fits altogether inside an incubator, lens-free microscopy becomes a unique tool to monitor cell cultures over several days. The high contrast phase shift images provide robust cell segmentation and tracking, and enable high throughput monitoring of individual cell dimensions, dry mass, and motility. They tested the multiwavelength lens-free video-microscope over a broad range of cell lines, including mesenchymal, endothelial, and epithelial cells. © 2017 International Society for Advancement of Cytometry.

Cell Segmentation for Image Cytometry: Advances, Insufficiencies, and Challenges

“…It has taken the community many decades and great endeavor to segment, identify, and analyze cells for explaining the cellular and molecular processes of health and disease. Studies have showed that cell segmentation can contribute to the better cell recognition in various fields of cell biology (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) and great advances have been achieved. However, it still has a long way to go before meeting the ultimate goal that the developed method can segment and identify different types of cells autonomously and the biologists can trust the segmentation and identification results blindly.…”

Quantitative phase imaging of adherent mammalian cells: a comparative study

“…Lens-free acquisitions were performed with a Cytonote microscope (Iprasense, Montpellier, France). This setup is inspired by the lens-free imaging system described in [17], which was modified to perform continuous monitoring of cellular cultures inside an incubator at a controlled temperature and humidity [15,16]. Multiple wavelength illumination is provided by a RGB LEDs with red (647 nm, FWHM 13 nm), green (527 nm, FWHM 21 nm) and blue (450 nm, FWHM 15 nm) color.…”

“…D in Eq. (15) measures the misfit between forward model predictions and actual measurements; since the variance of M Z is constant, equal to 1/4, the data matching term can be written as a χ 2 criterion: (16) where N p is the number of pixel of acquisition, N c is the number of color (here N c = 3) used and where for the sake of simplicity of the text, the symbol ∫ dì r is used to replace the discrete summation: for any function f , such an integral replace:…”

“…In this article, we present a comparison study of three different QPI techniques. We used three commercially available QPI instruments: digital holographic microscopy (DHM) [12], quadriwave lateral sheering interferometry (LSI) [13] and lens-free microscopy (LFM) [14][15][16]. To ensure consistency, the measurements with the different techniques were performed on the same day, in the same room and on the same set of cells.…”

Curvature Dependent constraints drive remodeling of epithelia

“…To follow epithelium formation within the alginate tubes at large as well as cellular scales, we took advantage of a lens-free microscope that allows the acquisition of large fields of view (up to 29.4 mm 2 , CMOS sensor) over long period of time (days) directly into the incubator (Allier et al, 2017). After an holographic reconstruction process, it is possible to obtain a phase image of the biological sample.…”