Navigation Links
Transparent fish to make human biology clearer
Date:2/6/2008

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.

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 skinreflective, 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.


'/>"/>

Contact: Elizabeth Andrews
elizabeth.andrews@childrens.harvard.edu
617-919-3110
Children's Hospital Boston
Source:Eurekalert  

Related medicine news :

1. Transparent Fish Gives New Window on Disease
2. Transparent zebrafish help researchers track breast cancer
3. Keystone Human Services Acquires Impact Systems, Inc.
4. Human Resource Executive(R) 6th Annual NY HR Week(TM) to Feature HRO World(TM) Conference & Expo
5. Connection between health of wetlands and humans in focus
6. Globetrotting black rat genes reveal spread of humans and diseases
7. A taxing issue: How human T-lymphotropic virus
8. Study finds genetic link to human herpes susceptibility
9. Common human viruses threaten endangered great apes
10. Humanities Texas Announces Winners of The First Humanities Texas Award
11. Evolutionary phenomenon in mice may explain human infertility
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Transparent fish to make human biology clearer
(Date:4/27/2017)... ... April 27, 2017 , ... The Incentive Research Foundation ... A Nudge Guide," a groundbreaking analysis of how behavioral economics can be applied ... immediately to IRR programs, the report highlights proven behavioral economics approaches and the ...
(Date:4/27/2017)... ... April 27, 2017 , ... Thinksport, ... the heels of Thinksport’s award-winning sunscreen they’ve used the same scientific approach to ... , Countless deodorants flood the aisles that contain harmful chemicals that should be ...
(Date:4/27/2017)... ... April 27, 2017 , ... Last night, ... CAREGiverSM of the Year for her extraordinary compassion and lifelong dedication to serve ... American professional caregivers for the prestigious award each year – identifying a CAREGiver ...
(Date:4/27/2017)... ... April 27, 2017 , ... Goodcents Deli Fresh Subs announced a franchise ... area this year. , The first new location will open at the corner ... at 84th and Northern Lights Drive this fall. And the third location is in ...
(Date:4/27/2017)... (PRWEB) , ... April 27, 2017 , ... Are you ... tragic spike in water-related accidents and drownings during the summer. While most of us ... that these situations occur every day. Very few people are taking the time to ...
Breaking Medicine News(10 mins):
(Date:4/18/2017)... Cogentix Medical, Inc. (NASDAQ: CGNT), a global medical device ... markets with innovative and proprietary products, will release financial ... after the market close on Tuesday, May 2, 2017. ... call and webcast to discuss its financial results the ... p.m. Eastern Time (3:30 p.m. Central Time). Darin ...
(Date:4/18/2017)... Research and Markets has announced the addition of the "Global ... ... at a CAGR of 6.35% during the period 2017-2021. ... based on an in-depth market analysis with inputs from industry experts. ... the coming years. The report also includes a discussion of the ...
(Date:4/18/2017)... and BLOOMINGTON, Minn. , ... IMMY ) ("Imprimis"), an ophthalmology-focused pharmaceutical ... ("Precision Lens"), today announced the signing of a ... Precision Lens will deploy a dedicated sales team ... in the U.S., primarily focused in 13 states ...
Breaking Medicine Technology: