Photon Imager

MacroLens fluorescence acquisition of a mosquito expressing DsRed in its salivary glands, infected with GFP expressing malaria.
The malaria sporozoites first home in the insect thorax before migrating to the salivary glands of the mosquito. Such a migration is thought to be facilitated by specific chemo-attractants.
The acquisition clearly shows the GFP expression of the parasite in the insect's thorax and the DsRed expressing salivary glands. This double labeled image was overlayed with a white light picture of the mosquito, and the movie shows the two pictures overlayed with different transparency levels. Click on the image to get a larger view of the signal image.

Courtesy of Dr. Shigeto Yoshida, Department of infection and immunity, Jichi Medical school, Saimata, Japan.

After UV excitation, the particles were injected in the animal and emitted light during several minutes based on the time delayed fluorescence principle. This technique gives the best of both worlds: the high contrast of bioluminescence and great signal of fluorescence.
Le Masne de Chermont et al, Nanoprobes with near-infrared persistent luminescence for in vivo imaging, Proc Natl Acad Sci USA, 2007 (May) (link)

Fluorescence Imaging to detect human multiple myeloma (MM) cells, 7 weeks after intravenous injection into RAG2cg knock-out mice on the basis of CD38 expression. Myeloma cells show specific, but random homing to and outgrowth in the bone marrow compartment. 48 hours before acquisition, the mice were injected with Alexa647 labeled anti-human CD38. Multiple Myeloma tumors can be localized at various location throughout in the bone marrow compartment.
Courtesy of Dr. Anton C.M. Martens, Dept. of Immunology, UMC-Utrecht, The Netherlands

Ca²⁺ responses in a 7 day-old mtGA-expressing mouse. The mouse was injected with kainic acid intra peritoneally (25 mg/Kg). Imaging started right after injection. The calcium waves activated the Aequorin-GFP BRET mechanism, resulting in light production direclty linked with the propagation of the calcium transients. Calcium release was observed to reach a peak 15 minutes after kainate injection.

From Rogers et al: Non-invasive in vivo imaging of calcium signaling in mice, PLoS ONE, 2(10): e974 (2007) (link)