Although bone marrow transplants have long been standard for acute leukemia, current treatments still rely on exact matches between donor and patient.
Now, scientists at the University of Perugia, Italy, and the Weizmann Institute of Science have improved on a method of transplanting bone marrow-based stem cells from a mismatched donor, making it safer for use when no exact match exists. They were invited to present their findings at the recent annual American Society of Hematology conference in New Orleans.
More than a decade ago, Prof. Yair Reisner of the Weizmann Institute's Immunology Department pioneered a method for transplanting stem cells from family members who are a partial match. Based on these studies (in mice), he joined forces with Prof. Massimo F. Martelli, Head of the Hematology and Clinical Immunology Section at the University of Perugia, to demonstrate in more than 300 patients that the cure rate of these so-called "mega dose" transplants is similar to that of transplants from matched, unrelated donors picked from international bone marrow donor registries. To combat the body's tendency to reject the foreign cells, these stem cells are stripped of immune cells called T cells and given in high doses that overwhelm the host's own immune system.
Although removing donor T cells from the bone marrow reduces the risk of graft-versus-host disease - caused when the T cells attack the recipient's tissues - the immune system is slow to recover after the transplant, leaving the patient at risk of serious infection. Doctors are faced with a difficult choice: Either remove the T cells from the bone marrow, increasing the risk of infection, or leave the T cells in the graft, putting the patient at risk for lethal graft-versus-host disease.
Martelli, working with Reisner, has now found a way to facilitate the recovery of the immune responses in recipients of T cell-depleted bone marrow transplants. In a clinical trial, 25 of 26 leukemia and lymphoma patients who received mismatched mega dose T cell-depleted stem cell transplants from relatives showed prompt immune recovery, and their immune systems were functioning well several months later.
The scientists knew that certain regulatory T cells (T regs), rather than causing graft-versus-host disease, could actually help to prevent it in mice. T regs have also been shown to keep other immune responses in check, including preventing autoimmune attacks on the body's own cells. In the present study, after purifying T regs from the donor's blood, the cells were infused intravenously into the cancer patients, who had previously undergone standard radiation and chemotherapy treatments. Three days later, the patients received the donor stem cells, along with another kind of T cell - those that fight disease.
The patients who underwent this procedure showed quick, lasting improvements in immune activity; most experienced no symptoms even though they received large doses of the T cells that are generally associated with lethal graft-versus-host disease.
Further follow up on these patients and additional clinical trials will be needed before the procedure can be widely adopted. But these results strongly suggest that T regs used in mega-dose stem cells will further enhance the cure rate for bone marrow transplant patients without a matched donor in the family.Prof. Yair Reisner's research is supported by the M.D. Moross Institute for Cancer Research; the Kirk Center for Childhood Cancer and Immunological Disorders; the Mario Negri Institute for Pharmacological Research Weizmann Institute of Science Exchange Program; the Gabrielle Rich Center for Transplantation Biology Research; the Russell Berrie Foundation; and Mr. and Mrs. Seymour Spira, Palm Beach Gardens, FL.
Prof. Reisner is the incumbent of the Henry H. Drake Professorial Chair in Immunology.
The Weizmann Institute of Science in Rehovot, Israel, is one of the world's top-ranking multidisciplinary research institutions. Noted for its wide-ranging exploration of the natural and exact sciences, the Institute is home to 2,600 scientists, students, technicians and supporting staff. Institute research efforts include the search for new ways of fighting disease and hunger, examining leading questions in mathematics and computer science, probing the physics of matter and the universe, creating novel materials and developing new strategies for protecting the environment.
Weizmann Institute news releases are posted on the World Wide Web at http://wis-wander.weizmann.ac.il, and are also available at http://www.eurekalert.org.
Yivsam Azgad | idw
Kidney tumor: Genetic trigger discovered
18.06.2018 | Julius-Maximilians-Universität Würzburg
New type of photosynthesis discovered
18.06.2018 | Imperial College London
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...
Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.
From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
18.06.2018 | Earth Sciences
18.06.2018 | Process Engineering
18.06.2018 | Life Sciences