Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Transparent fish to make human biology clearer

07.02.2008
Researchers can watch cancer spread and bone marrow engraft

Zebrafish are genetically similar to humans and are good models for human biology and disease. Now, researchers at Children's Hospital Boston have created a zebrafish that is transparent throughout its life. The new fish allows scientists to directly view its internal organs, and observe processes like tumor metastasis and blood production after bone-marrow transplant in a living organism.


Caption: The transparent zebrafish.
Credit: Richard Whtie, MD, PhD

The fish, described in the February 7 issue of Cell Stem Cell, was created by Richard White, MD, PhD, a clinical fellow in the Stem Cell Program at Children's, with others in the laboratory of Leonard Zon, PhD.

The classic method for studying human diseases in animals is to allow the animal to get the disease, kill and dissect the animal, then ask, "what happened?" But in cancer and other fast-changing processes that traverse the body, this method is bound to miss something. "It's like taking a photograph when you need a video," says White, also an instructor of medicine at the Dana-Farber Cancer Institute.

Zebrafish embryos have enabled researchers to study disease in live organisms, since they are transparent. But zebrafish adults are opaque. "Everything after four weeks has been invisible to us," says White.

White's first experiment on the zebrafish examined how a cancer spreads. "The process by which a tumor goes from being localized to widespread and ultimately fatal is the most vexing problem that oncologists face," says White. "We don't know why cancer cells decide to move away from their primary site to other parts in the body."

White created a fluorescent melanoma tumor in the transparent fish's abdominal cavity. Viewing the fish under a microscope, White saw the cancer cells begin to spread within five days. He even saw individual cells metastasize, something that has not been observed, so readily and in real-time, in a living organism.

The spreading melanoma cells appeared to "home" to the skin after leaving the abdominal cavity. "This told us that when tumor cells spread to other parts in the body, they don't do it randomly," says White. "They know where to go."

White plans to study tumor cell homing, then look for ways to modify the tumor cells or cells of the host so that the spreading cells never find their new location.

The fish may also answer questions about stem cell transplants. While transplants of blood-forming stem cells help cancer patients rebuild healthy blood, some transplants don't "take," for reasons that are unknown. Scientists have lacked a full understanding what steps blood stem cells must take to do their job, says White.

White showed the process is observable in the fish. He first irradiated a transparent fish's bone marrow, then transplanted fluorescent blood-forming stem cells from another zebrafish. By four weeks, the fluorescent stem cells had visibly migrated and grown in the fish's bone marrow, which is in the kidney. Even individual stem cells were visible, something researchers haven't easily observed in a living organism, White says.

By studying how the stem cells embed and build blood in the fish, scientists can look for ways to help patients rebuild their blood faster. Drugs and genes could be tested in the living fish, with direct observation of results, White says.

White created the transparent fish simply by mating two existing zebrafish breeds. Zebrafish have three pigments in their skin—reflective, black, and yellow. White mated a breed that lacks reflective pigment, called "roy orbison," with one that lacks black pigment, called "nacre." The offspring had only yellow pigment in their skin, essentially looking clear. White named the new breed "casper."

The fish's brain, heart, and digestive tract are also visible, allowing researchers to study genetic defects of these organs from early embryonic development through adulthood. White hopes this tool will provide insight into how mutated genes cause diseases ranging from Alzheimer's disease to inflammatory bowel disease.

"What happens in a living organism is different than what happens in a dish," White says.

Elizabeth Andrews | EurekAlert!
Further information:
http://www.childrenshospital.org/newsroom

Further reports about: Pigment Stem Transparent White organism spread stem cells transplant

More articles from Life Sciences:

nachricht Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>