Features | Partner Sites | Information | LinkXpress
Sign In
PZ HTL SA
GLOBETECH PUBLISHING
GLOBETECH PUBLISHING

T-cells Derived from Human Embryonic Stem Cells May Prevent Graft Rejection

By BiotechDaily International staff writers
Posted on 29 May 2013
Image: Senior author Dr. Matthias Hebrok (Photo courtesy of the University of California, San Francisco).
Image: Senior author Dr. Matthias Hebrok (Photo courtesy of the University of California, San Francisco).
Image: Contributing author Dr. Mark Anderson (Photo courtesy of the University of California, San Francisco).
Image: Contributing author Dr. Mark Anderson (Photo courtesy of the University of California, San Francisco).
A recent paper described the development of a method for using human embryonic stem cells (hESCs) to generate fully functional thymus tissue capable of supporting T-cell development and proliferation.

Inducing immune tolerance to prevent rejection is a key step toward successful engraftment of stem-cell-derived tissue in a clinical setting. Using human pluripotent stem cells to generate thymic epithelial cells (TECs) capable of supporting T-cell development represents a promising approach to reach this goal; however, progress toward generating functional TECs has been limited.

Investigators at the University of California, San Francisco (USA) developed a new method for directing differentiation of hESCs into thymic epithelial progenitors (TEPs), cells that mature into TECs. The in vitro method was based on the precise chronological regulation of several signaling factors including TGF-beta (transforming growth factor-beta), BMP4 (bone morphogenetic protein 4), Wnt (wingless-type MMTV integration site family), Shh (sonic hedgehog), and FGF (fibroblast growth factor).

Timing the activation of these signaling factors was critical. "If we used one factor for a day longer or shorter it would not work," said senior author Dr. Matthias Hebrok, professor of diabetes research at the University of California, San Francisco. "It would be like driving down the highway and missing your exit."

Results published in the May 16, 2013, online edition of the journal Cell Stem Cell revealed that the hESC-derived TEPs matured into functional TECs that supported T-cell development upon transplantation into thymus-deficient mice. Furthermore, the engrafted TEPs produced T-cells capable of in vitro proliferation as well as in vivo immune responses.

"The thymus is an environment in which T-cells mature, and where they also are instructed on the difference between self and nonself," said contributing author Dr. Mark Anderson, professor of medicine at the University of California, San Francisco. "Some T cells are prepared by the thymus to attack foreign invaders—including transplants, while T cells that would attack our own tissues normally are eliminated in the thymus."

The protocol described in this study prompted only about 15% of hESCs to differentiate into functional thymus tissue. Even so, Dr. Anderson said, "We now have developed a tool that allows us to modulate the immune system in a manner that we never had before."

Related Links:
University of California, San Francisco



Channels

Drug Discovery

view channel

Retinoic Acid Prevents Precancerous Breast Cells from Progressing to Full-Blown Cancer

Retinoic acid, a derivative of vitamin A, was found to prevent pre-cancerous breast cells from progressing to full-blown cancer but did not have any effect on breast tumor cells. Investigators at Thomas Jefferson University (Philadelphia, PA, USA) worked with a novel breast cancer model that had been developed by treating... Read more

Biochemistry

view channel

Mitochondrial Cause of Aging Can Be Reversed

Researchers have found a cause of aging in lab animals that can be reversed, possibly providing an avenue for new treatments for age-related diseases including type 2 diabetes, cancer, muscle wasting, and inflammatory diseases. The researchers plan to begin human trials late 2014. The study, which was published December... Read more

Therapeutics

view channel

Cytokine Identified That Causes Mucositis in Cancer Therapy Patients

The action of the cytokine interleukin 1-beta (IL-1beta) has been found to underlie the onset of mucositis, a common, severe side effect of chemotherapy and irradiation of cancer patients. Mucositis occurs as a result of cell death in reaction to chemo- or radiotherapy. The mucosal lining of the mouth becomes thin, may... Read more

Business

view channel

Analytical Sciences Trade Fair Declared a Rousing Success

Organizers of this year's 24th "analytica" biosciences trade fair have reported significant increases in both the number of visitors and exhibitors compared to the 2012 event. The analytica trade fair for laboratory technology, analysis, and biotechnology has been held at the Munich (Germany) Trade Fair Center every... Read more
 
Copyright © 2000-2014 Globetech Media. All rights reserved.