Regulatory T cells (Tregs) are a type of immune cell that play an extremely important role in maintaining stability in the body and preventing the body’s immune system from attacking its own cells and organs. This unique property makes Tregs extremely valuable to researchers as a potential treatment for immune related issues. One of these is autoimmune disease, which is a disease in which the body’s own immune system attacks healthy cells. Some examples of this are type 1 diabetes, multiple sclerosis, and lupus. Another immune related issue is graft vs. host disease (GvHD), which can occur after receiving a transplantation where the donated bone marrow or stem cells start attacking the recipient.
For this reason, researchers at the La Jolla Institute for Immunology (LJI) and Emory University School of Medicine, partially supported by a CIRM training grant , have been working to generate stable induced Tregs (iTregs) for treating autoimmune diseases and rejection of a transplanted organ. The teams were led by LJI professor Anjana Rao, Ph.D, and Emory instructor Benjamin G. Barwick, Ph.D. The two team study showed evidence that vitamin C and and specific proteins called TET can be combined to give Tregs their life-saving power. Studies have previously found that vitamin C can enhance the activity of TET proteins and prompt the generation of stable iTregs under lab conditions.
For this study, the researchers also analyzed gene expression patterns as well as changes that altered the physical structure of DNA in the induced Tregs. The team found a major modification involving the DNA itself and showed that TET enzymes were also involved. All of these interactions can eventually change how cells “read” the DNA code. They also observed the alteration of DNA accessibility which depends on whether DNA is loosely or tightly coiled. As the DNA coils unwind, regulatory regions become exposed which subsequently influence gene expression.
In a news release, LJI instructor Xiaojing Yue, Ph.D elaborated on the results of this study.
“Vitamin C can be used to stabilize iTregs generated in vitro. We hope that these kinds of induced Tregs can be used in the future for treatment of autoimmune diseases and organ transplantation.”