Fluorescence Microscopy

Here is a picture I made at work with some amazing technology. This is a sample of HeLa cells, which are human cancer cells derived from a cervical cancer from a woman named Henrietta Lacks some time in the 1950s (without her permission...). They have since devolved into a cell-line able of infinate self-replication (hence they are used in a variety of medical experiments). So anyways, to visualize these cells I have stained the nucleus blue and my protein of interest red.

...which absorbs the
emmited photons and then fluoresces
red...

Because proteins are too small to be seen with microscopes I had to be tricky to be able to see this particular signalling molecule. First I added an antibody against my molecule (so basically I made a large protein which will stick selectively to my protein), and a second antibody against my first antibody with a luminescent protein attached to it (derived from a phosfluorescent jellyfish protein!!). In the solution is a fluor which absorbs the emmitted photons and then fluoresces bright red under the proper wavelength. I then took a picture of these cells and imaged with the red wavelength, revealing that my protein is indeed in the cytoplasm of the cell (i.e. not in the middle of the cell). The blue staining was a similar process, except staining for DNA in the nucleus. I then imaged a second time under a blue wavelength of light, which allowed me to see the nuclei of the cells only. Using the computer that controls this microscope I was able to merge the two images to create the picture above. Fun, eh?