Navigation Links
Carnegie Mellon develops non-invasive technique to detect transplant rejection at cellular level

Carnegie Mellon University scientist Chien Ho and his colleagues have developed a promising tool that uses magnetic resonance imaging (MRI) to track immune cells as they infiltrate a transplanted heart in the early stages of organ rejection. This pre-clinical advance, described in an upcoming issue of the Proceedings of the National Academy of Sciences (PNAS), ultimately could provide a non-invasive way to detect transplant rejection in patients.

"We have reported for the first time the ability to monitor single immune cells in a live animal using MRI. This could revolutionize the management of transplant patients," said Ho, professor of biological sciences at the Mellon College of Science.

"Successful translation of this work to the clinic ultimately will reduce the number of biopsy procedures and should greatly improve the quality of life for cardiac transplant patients, especially children," added Ho, who directs the Pittsburgh NMR Center for Biomedical Research. "Perhaps most importantly, this advance will allow doctors to provide highly personalized care that could prevent transplant rejection."

Organ transplantation is the preferred clinical approach to treat end-stage organ failure, but transplant patients face a lifetime of immunosuppressive therapy and the risk of losing the new organ due to rejection. Physicians typically monitor patients for organ rejection following a heart transplant by performing frequent heart biopsies for the first year. Heart biopsies are invasive procedures that involve threading a catheter through the jugular vein to the heart's right ventricle and snipping out several tiny pieces of tissue. A pathologist then tests the tissue to identify the presence of immune cells (such as macrophages) as well as other pathological changes in the transplanted heart tissue that indicate the graft is being rejected by the body's immune system.

These procedures are costly, uncomfortable and must be repeated annually for a few years to monitor and treat any rejection. Biopsies also are problematic, according to Ho, because they do not look at the whole organ. By only sampling several small areas, a biopsy may miss the area of the transplanted organ where immune cells are gathering -- one of the first signs of rejection.

Ho's novel approach investigates transplant rejection non-invasively by observing macrophage accumulation in heart tissues using MRI.

"We were able to use MRI to visualize individual macrophages. By tracking individual cells, we also were able to observe, for the first time, that rejection progresses from the outside of the heart to the inside," said Ho. "Up to now, this phenomenon hasn't been observed in pre-clinical or clinical research because biopsy samples are very limited in location and size."

The reported findings also have broader implications for biology and medicine, according to Ho.

"We now have the ability to visualize non-invasively and with sensitivity individual cells and their movement to targeted sites. Our new approach offers almost unlimited potential for monitoring cell therapies, such as those using stem cells, and for tracking cellular and developmental processes," Ho said.

For the research reported in PNAS, Yijen Wu, research biologist at the Pittsburgh NMR Center for Biomedical Research, tagged macrophages with nanometer (USPIO)- or micrometer (MPIO)-sized paramagnetic iron oxide particles, which are very sensitive to the magnetic fields used during MRI. Wu injected the MPIO or USPIO particles into rats that had received heart transplants three days earlier. Macrophages, which typically ingest foreign materials inside the body (bacteria, for example), incorporated the particles. Using MRI, the researchers then track tagged macrophages that infiltrate transplanted hearts. The locations of the tagged macrophages are highly defined and appear circular in shape, said Wu. This finding indicates that the new, real-time tracking method is very good at pinpointing exactly when and where rejection is taking place.

The researchers used a heterotropic heart model to study organ rejection. In this model, a rat receives a second functional heart, which is grafted into its abdomen. The rat's native heart functions normally. In this way, the researchers can study how a transplanted heart changes through sequential stages of rejection while the rat stays healthy. This aspect of the research was conducted primarily by Qing Ye, a research biologist at the Pittsburgh NMR Center for Biomedical Research.

Ho's team at the Pittsburgh NMR Center for Biomedical Research is now pursuing research using larger animal models. They are collaborating with researchers at the University of Pittsburgh School of Medicine, including Dr. David Cooper, professor of surgery in the Thomas E. Starzl Transplantation Institute; Dr. Jeffrey Teuteberg, assistant professor of medicine at the Cardiovascular Institute, Heart Failure/Transplantation; and Dr. Fernando Boada, associate professor in the Department of Radiology.


'"/>

Source:Carnegie Mellon University


Related biology news :

1. Carnegie Mellon scientists develop tool that uses MRI to visualize gene expression in living animals
2. Robot-based system developed at Carnegie Mellon detects life in Chiles Atacama desert
3. Green catalyst destroys pesticides and munitions toxins, finds Carnegie Mellon University
4. Carnegie Mellon University research reveals how cells process large genes
5. Carnegie Mellon cyLab researchers work to develop new red tide monitoring
6. Team led by Carnegie Mellon University scientist finds first evidence of a living memory trace
7. Carnegie Mellon scientists create PNA molecule with potential to build nanodevices
8. Carnegie Mellon U. transforms DNA microarrays with standard Internet communications tool
9. Carnegie Mellon scientists show brain uses optimal code for sound
10. DNA conclusive yet still controversial, Carnegie Mellon professor says
11. Teens unaware of sexually transmitted diseases until they catch one, Carnegie Mellon study finds
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:11/9/2018)... ... November 08, 2018 , ... Boekel Scientific launches a new ... as dry bath incubators are used in laboratories worldwide for controlling and maintaining ... new heating blocks, Boekel Scientific used the same interface design as their recently ...
(Date:11/7/2018)... Va. (PRWEB) , ... November 07, 2018 , ... ... today that Barb Geiger, a senior Clinical Operations professional with extensive experience in ... development in the US, Australia, Latin America, Europe, and Asia, has joined the ...
(Date:11/6/2018)... ... November 06, 2018 , ... uBiome, the leader in microbial genomics, ... the University of California, San Francisco (UCSF) and Co-President of Chan Zuckerberg Biohub, to ... uBiome since 2013, and we are honored that he is expanding his role as ...
Breaking Biology News(10 mins):
(Date:11/13/2018)... Sandy Springs, GA (PRWEB) , ... November 12, ... ... cosmetic dentist with state-of-the-art practices in Alpharetta and Sandy Springs, now welcomes ... clear aligners provide a discreet and comfortable alternative to traditional braces in the ...
(Date:11/11/2018)... DIEGO (PRWEB) , ... November 09, 2018 , ... Triple ... a CES® 2019 Innovation Awards Honoree for DFree ®, the first ... notifies you when it’s time to go to the bathroom. The announcement was made ...
(Date:11/7/2018)... (PRWEB) , ... November 07, 2018 , ... ... has been leading a campaign to increase awareness of the adult tissue stem ... During the month of November, the company is intensifying this effort with new ...
(Date:11/5/2018)... (PRWEB) , ... November 05, 2018 , ... ... and telemedicine company backed by Siemens Healthineers and several healthcare VC firms announces ... radiology solution and making a history by purchasing tokens and obtaining its first ...
Breaking Biology Technology: