Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mayo researchers observe genetic fusion of human, animal cells -may help explain origin of AIDS

09.01.2004


Mayo Clinic genomics researchers are the first to demonstrate that mixing of genetic material can occur naturally, in a living body. The researchers have discovered conditions in which pig cells and human cells can fuse together in the body to yield hybrid cells that contain genetic material from both species and carry a swine virus similar to HIV (the virus that causes AIDS) that can infect normal human cells.



While the research does not answer the question of whether this infection can cause actual disease in humans, it does provide scientists with a new way to understand how viral infections can pass from animals to humans.

"What we found was completely unexpected," says Jeffrey Platt, M.D., director of the Mayo Clinic Transplantation Biology Program. "This observation helps explain how a retrovirus can jump from one species to another -- and that may speed discovery about the origin of diseases such as AIDS and SARS. The discovery also may help explain how cells in the circulation may become part of the solid tissue." The Mayo Clinic research appears in the online Express edition of the FASEB Journal. (www.fasebj.org) published by the Federation of American Societies for Experimental Biology. The print article will appear in the March issue of the journal (volume 18, issue 3).


Known as "zoonosis or zoonotic infection," the movement of an infectious agent between animals and humans is of intense interest to those who study public health, infectious diseases, immunology and transplantation. Some viruses, such as influenza, are well known to pass from one species to another. Other viruses do not appear to easily cross species -- and yet do so under rare, unknown circumstances.

Scientists want to know how and why viruses cross species because zoonosis may underlie some of the most devastating diseases. For example, researchers have long believed the HIV virus that causes AIDS in humans originated in wild primate populations and crossed into humans a few decades ago. More recently, scientists have thought that the coronavirus responsible for SARS crossed into humans from wild animals such as the palm civet cats of Asia.

A Possible New Model for Understanding AIDS

In the research reported today, Mayo Clinic investigators implanted human blood stem cells into fetal pigs. The pigs look and behave like normal pigs. But cellular analysis shows they have some human blood cells, as well as some cells that are hybrids -- part human, part pig -- in their blood, and in some of their organs. Molecular examination shows the hybrid cells have one nucleus with genetic materials from both the human and the pig. Importantly, the hybrid cells were found to have the porcine endogenous retrovirus, a distant cousin of HIV, and to be able to transmit that virus to uninfected human cells.

Background: What Led to This Research?

The Mayo Clinic research team has long been interested -- and is a world leader -- in xenotransplantation (ZEE-no-transplantation). This is an experimental field within transplant biology in which specially bred and raised pigs might eventually become donors for humans to meet the drastic shortage of suitable donor organs. Worldwide, thousands of people suffer failure of such organs as the liver, kidney, heart, lung and pancreas and require transplants -- but face death due to shortage of suitable donor organs. Xenotransplantation is just one experimental avenue being explored as a way to meet this shortage.

One central concern of investigators is the potential for zoonotic transmission of disease when an animal organ is surgically implanted into a human. One virus of concern is the porcine endogenous retrovirus, which is present in all pigs. The current research provided two important discoveries: the virus can pass to human cells in the body and it can be infectious. But whether it can actually cause disease in humans is not yet known.

Says Dr. Platt, "Perhaps this model or one like it can help to answer this question. And perhaps similar models can be used to identify other viruses of concern before outbreaks occur in humans."

The Next Step

The experiment has been repeated a number of times, but it needs to be further scrutinized. "We’re really working hard to figure out how it happened, and what implications it might have beyond the transmission of the one virus we studied," Dr. Platt says.

The research was conducted in the Transplantation Biology Program at Mayo Clinic. In addition to Dr. Platt, the research team consisted of Brenda Ogle, Ph.D., first author of the article, and Marilia Cascalho, M.D., Ph.D., who was in charge of genetics in the study.


Mayo Clinic conducts research in medical genomics in order to improve patient care. Its scientists and clinical investigators strive to turn laboratory discoveries into beneficial therapies as quickly as possible.

Bob Nellis | EurekAlert!
Further information:
http://www.mayo.edu/

More articles from Life Sciences:

nachricht 'Lipid asymmetry' plays key role in activating immune cells
20.02.2018 | Biophysical Society

nachricht New printing technique uses cells and molecules to recreate biological structures
20.02.2018 | Queen Mary University of London

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

'Lipid asymmetry' plays key role in activating immune cells

20.02.2018 | Life Sciences

MRI technique differentiates benign breast lesions from malignancies

20.02.2018 | Medical Engineering

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>