Navigation Links
Gene pattern may identify kidney transplant recipients who don't need lifelong anti-rejection drugs

To prevent rejection of their new kidneys, kidney transplant recipients need to take immunosuppressive drugs for the rest of their lives. A handful of people, out of the thousands who have undergone transplantation, have been able to stop taking these drugs without losing their kidneys.

Researchers studying these rare individuals have identified a pattern of genes turned on in their white blood cells, which may one day be used to help identify other transplant recipients who could reduce or completely taper their immunosuppressive therapy without ill effect.

The study, whose results were reported this week in the Journal of Clinical Investigation, was performed by the Immune Tolerance Network (ITN), an international research consortium with headquarters at University of California, San Francisco.

The paper's lead author is Kenneth Newell, MD, PhD, director of the Living Donor Kidney Program at Emory Transplant Center and professor of surgery at Emory University School of Medicine. Senior authors are Laurence Turka, MD, of Harvard Medical School and Beth Israel Deaconess Medical Center, and Vicki Seyfert-Margolis, PhD, former chief scientific officer at the ITN, now an advisor in the Food and Drug Administration Office of the Chief Scientist.

The authors emphasize that their study looked at "tolerant" patients. These are patients who had stopped taking their prescribed immunosuppressive medications for at least a year, yet did not reject their kidneys. They are not encouraging others to follow the same course of action.

"The signature that we discovered in these individuals may be useful for identifying kidney transplant recipients who are already tolerant. Whether or not this same signature will identify those kidney transplant recipients still taking immunosuppressive medications who are predisposed to developing tolerance in the future remains unknown," Newell says. "Carefully supervised studies will be necessary to answer this question as well as to determine whether attempting to completely withdraw all immunosuppressive drugs will prove advantageous in the long term."

A representative of "tolerant" transplant recipients is Lisa Robinson, who owns her own real estate company in Colorado Springs. She received a kidney from her sister at age 30 in 1996. Robinson needed the kidney transplant because of Wegener's granulomatosis, a condition in which her immune system was attacking her own blood vessels, causing kidney and lung damage.

Three years after her kidney transplant, she found it hard to tolerate the side effects of the immunosuppressive drugs, which included swelling, weight gain and depression. On top of that, her creatinine levels were rising, indicating that her donated kidney was losing function. Without explicit approval from her doctor, she decided to taper off her drugs, first cyclosporine and then steroids.

"This turned out to be the right choice for me, but I'm not suggesting that others do what I did," she says. "Everyone has to figure out what works for them. My main motivation was that I didn't want to go through another kidney transplant."

The drugs taken by transplant recipients can reduce an individual's ability to fight infections, lead to high blood pressure and high blood sugar and, ironically, tend to damage the kidney over time. In rare cases, a physician may stop a transplant recipient's immunosuppressive drugs because of a serious medical problem such as cancer or life-threatening infection; in other cases, transplant recipients decide to reduce or stop their immunosuppression therapy against their physicians' advice, even though by doing so, they risk losing their transplanted organ. Only in a very small percentage of such cases, rejection does not occur after the drugs are stopped.

"In the vast majority of patients, stopping or reducing immunosuppression medications without doctor supervision will have serious health consequences, including loss of the transplanted kidney," cautions Newell. "We certainly don't encourage anyone to try this on their own."

The ITN study examined 25 kidney transplant recipients who had ceased taking their immunosuppressive drugs and yet had retained normal kidney function for more than one year. The researchers compared this group with two other groups: recipients who were still taking their medication and had healthy kidneys, as well as healthy, non-transplanted controls.

The ITN team analyzed the genes turned on in samples of blood cells from each of the three groups and observed that the transplant recipients who were not taking medication had a distinct pattern of genes turned on in B cells, a type of white blood cell. Further study showed that zeroing in on three B cell genes could distinguish patients who had stopped taking their medications yet maintained good graft function.

White blood cells include both T and B cells. Most studies of immune tolerance have focused on the role of a subset of T cells, called regulatory T cells (Tregs). More recent work in animal models, however, indicates that some kinds of B cells may also help regulate the immune system and promote tolerance of a transplanted organ.

"We expected to find a difference between the tolerant and immunosuppression groups in the genes associated with Tregs," Newell says. "However, we were surprised that our data showed that B cell genes may play an important role in maintaining and possibly inducing tolerance to transplanted organs."

A European group that conducted a similar study in kidney transplant patients found corroborating results, which appear in the same issue of the Journal of Clinical Investigation.


Contact: Holly Korschun
Emory University

Related medicine news :

1. Bees Can Be Trained to Recognize Face-Like Patterns
2. New Paperback Dating Advice Book, Love in 90 Days, Reveals 16 Men's Dead-End Dating Patterns and What To Do About Them
3. Wistar-led research team discovers genetic pattern that indicates early-stage lung cancer
4. Researchers find new patterns in H1N1 deaths
5. Study Offers Insights Into Male Pattern Baldness
6. Research identifies patterns of CD24, a novel biomarker for non-small cell lung carcinomas
7. Genetic pattern that predicts leukemia relapse discovered
8. Genetic Pattern May Predict Leukemia Relapse
9. Gene pattern may identify kidney transplant recipients who dont need life-long anti-rejection drugs
10. UCSF Researchers Identify Regulator of Human Sperm Cells
11. NIH scientists identify maternal and fetal genes that increase preterm birth risk
Post Your Comments:
(Date:11/28/2015)... ... November 28, 2015 , ... Pixel Film Studios is back again with ... the possibilities are endless. Users have full control over angle of view, speed method, ... users are sure to get heads to turn. , ProPanel: Pulse offers fully customizable ...
(Date:11/27/2015)... (PRWEB) , ... November 27, 2015 , ... According to ... out by the University of Toronto and the University of British Columbia suggested that ... for head injuries. The article explains that part of the reason for the controversial ...
(Date:11/27/2015)... ... November 27, 2015 , ... A team of Swiss doctors has ... it. Surviving Mesothelioma has just posted the findings on the website. Click here ... the cases of 136 mesothelioma patients who were treated with chemotherapy followed by EPP ...
(Date:11/27/2015)... ... 2015 , ... Lizzie’s Lice Pickers just announced a special promotion that will ... their purchase of lice treatment product. In addition, customers will receive a complimentary head ... “Finding lice is a sure way to ruin the holidays, so we encourage all ...
(Date:11/27/2015)... ... November 27, 2015 , ... MPWH, the No.1 Herpes-only dating community in the world, revealed that ... ). More than 3.7 billion people under the age of 50 – or 67% ... WHO's first global estimates of HSV-1 infection . , "The data shocks us highly!" ...
Breaking Medicine News(10 mins):
(Date:11/25/2015)... Nov. 25, 2015  Amgen (NASDAQ: AMGN ) ... (BLA) with the United States ... a biosimilar candidate to Humira ® (adalimumab). Amgen ... submitted to the FDA and represents Amgen,s first BLA ... E. Harper , M.D., executive vice president of Research ...
(Date:11/25/2015)... N.Y. , Nov. 25, 2015  Linden Care, ... and optimizing treatment outcomes for patients suffering from chronic ... request for a Temporary Restraining Order (TRO) enjoining Express ... the two companies. --> ... pursuing all of its legal options. ...
(Date:11/25/2015)... On Tuesday, November 24, 2015, the ... Wright Medical Technology, Inc. for product liability and ... implant device, awarded $11 million in favor of ... and three days of deliberations, the jury found ... designed and unreasonably dangerous, and that Wright Medical ...
Breaking Medicine Technology: