Single Cell Optical Manipulations

CLaP takes advantage of the lasers of a confocal microscope to bind biotin molecules to the plasma membrane of individually selected cells. Streptavidin of different colors are used to label cells or streptavidin-coated ferromagnetic beads and a simple magnet can be used to capture only illuminated cells with high purity. This novel technology allows to explore many biological processes of interest in the fields of axon guidance, cell migration, cancer biology, immunology and many more.

Fluorescent cancer cells; some decorated with ferromagnetic beads

We adapted CLaP to different applications :

Icon of a 3 cells, one being fluorescent

CLaP

Single-cell labeling

Icon of 3 cells, one being pulled by a magnet

scMOCa

Single-cell capture

Icon of a Laser shining on a microscopy slide

LAPAP

Protein patterning

CLaP

Single-cell labeling

schematic CLaP 1 out of 4

schematic CLaP 2 out of 4

schematic CLaP 3 out of 4

schematic CLaP 4 out of 4

Cells are incubated with B4F, a small molecule that can easily reach the cell membrane, including the space between the glass surface and the cell. A laser beam photobleaches and crosslinks fluorescein-conjugated biotin. After rinsing, only illuminated cells retain biotin molecules on their plasma membrane and are revealed with fluorescent streptavidin. Biotin molecules attached to the plasma membrane freely diffuse along the lipid bilayer to yield a rather uniform distribution of fluorophores throughout the cell.

Selected Publication:

Binan L, et al. (2016) Live single-cell laser tag. Nat Commun. 2016 May 20;7:11636. pdf

CLaP Gallery of Images:

scMOCa

Single-cell capture

schematic scMOCa 1 out of 5

schematic scMOCa 2 out of 5

schematic scMOCa 3 out of 5

schematic scMOCa 4 out of 5

schematic scMOCa 5 out of 5

Biotin-4-fluorescein is crosslinked to cell membranes with a laser. Biotin-tagged cells are labeled with streptavidin-coated ferromagnetic beads and captured with a magnet.

Selected publications:

Binan L, et al. (2019) Opto-magnetic capture of individual cells based on visual phenotype. eLife 2019;8:e45239. PDF

scMOCa Gallery of Images:

LAPAP

Pattern for cell guidance

schematic LAPAP 1 out of 4

schematic LAPAP 2 out of 4

schematic LAPAP 3 out of 4

schematic LAPAP 4 out of 4

We have developed a technique to functionalise cell culture substrates with fluorescent labels, called Laser-Assisted Protein Adsorption by Photobleaching (LAPAP). This technique consist of photobleaching a fluorophore conjugated to molecules such as axon guidance cues or other chemotactic cues. By adjusting the intensity and the location of the laser, we create a haptotactic gradient for cells to follow.

Selected publications:

Bélisle JM, et al. (2008) Patterning protein concentration using laser-assisted adsorption by photobleaching, LAPAP. Lab Chip. 2008 Dec;8(12):2164-7. PDF

LAPAP Gallery of Images: