Release date: 2014-06-17 American scientists have recently used human-induced pluripotent stem cells to develop microscopic retinas with three-dimensional structure and sensitivity to light in the laboratory. This brings hope to patients who will treat retinal diseases and even blindness in the future. A paper on this research was published in the new issue of the British journal Nature-Communication. The first author of the paper, Zhong Xiufeng of Johns Hopkins University in the United States, told Xinhua News Agency that she and her colleagues used human-induced pluripotent stem cells to produce a "structuralally intact, functionally mature retina" in a culture dish. This retina is similar in structure and composition to the retina of the human eye and is sensitive. Stem cells are a class of cells that have the potential to differentiate into various organ tissues. There are a large number of such cells in embryos, which are called embryonic stem cells. In recent years, the scientific community has discovered that the use of genetic "reprogramming" techniques to treat adult cells, such as skin fibroblasts or blood cells, allows them to return to the embryonic stem cell state, thereby gaining the ability to multi-directionally differentiate, so that the resulting cells are called Inducing pluripotent stem cells. Zhong Xiufeng said that this study gradually cultivated human induced pluripotent stem cells into retinal precursor cells, which further differentiated into retinal tissues with three-dimensional structure. This retinal tissue contains all the cellular components of the retina of the human eye, in which various cells are spontaneously and orderly layered to form a tissue structure, which is similar to the structural level of the retina of the human eye. What excites the researchers most is that the photoreceptor cells in the retinal tissue that respond to light stimuli develop very maturely. The cells not only synthesize the proteins necessary for sensitization, but also generate important structures necessary for sensitization. The "outer node" structure, which is the place where photoreceptors convert light signals into bioelectrical signals. "For decades, the research community has not developed the 'outer node' structure of photoreceptor cells outside the body. This is a scientific problem," said Zhong Xiufeng. "We have achieved success, which is a huge advance in the field of retinal regeneration." Experiments have shown that when light waves illuminate the above photoreceptor cells, the cells undergo bioelectrical reactions. The waveform of this bioelectrical reaction is similar to that of photoreceptor cells when the human eye sees light. However, Zhong Xiufeng also pointed out that when people look at things, sensitization is only the first step, and other cells in the retina need to transmit bioelectrical signals to the brain to form a visual image. The diameter of the retina cultivated in this study was only about 1 mm in diameter, and it was not fully developed and was not as large as the retina of the human eye. For the significance of using human induced pluripotent stem cells to cultivate micro retina, Zhong Xiufeng said that one can be used as a research material to explore the cause of retinal diseases, rather than relying mainly on animals such as mice, the results of such research should be more reliable; It is possible for a personalized medicine, such as the use of micro retinas cultured in vitro to test the effectiveness of drugs, or for retinal cell transplantation, replacing the retinal cells that cause disease or death in the patient's eyes, bringing them back bright. Zhong Xiufeng also stressed that the retina they now cultivate cannot be transplanted into the human eye to treat diseases immediately. There are still many important issues to be explored. Source: China Science and Technology Network - Technology Daily Swing Turnstile,Swing Gate Turnstile,Turnstile Swing Gate,Sliding Gate Turnstile Shenzhen Unisec Technology Co.,ltd , https://www.uniqscansecurity.com