Heavyweight! Prof. Gang Zhao, the main committee member of Yinfeng Cryomedicine Specialized Committee, published another article "Advanced Cryopreservation Engineering Strategies - A Critical Step in Utilizing Stem Cell Products".
Cryopreservation is known as the technique of solidifying time, by cooling biological materials (e.g. cells, tissues and organs) to low temperatures with the addition of cryoprotectants (generally -196°C liquid nitrogen preservation), and then rewarming them to normal temperatures (37°C) in an effective manner when needed, at which time the biological samples can still be restored and maintain their activity.
In recent years, low-temperature biomedicine, a less popular subject, is attracting more and more attention, attracting more and more scientists to join it. Among them, the cryopreservation technology of cells, tissues and organs, and even the entire human body continues to make progress and is gradually used in clinical applications.
On June 30, 2023, Science Magazine published the article "Frozen in time" by Warren Cornwall, detailing the first successful transplantation of vitrified-preserved and nanoheated rat kidneys by Professor John Bischof's team at the University of Minnesota (UMN). . As the most exciting research in the field of cryopreservation of tissues and organs, this article successfully appeared on the cover of Science, Volume 380, Issue 6652.
At present, cryopreservation technology (temperature at minus 196°C) has become the most commonly used and effective long-term preservation method for single cells, and has successfully achieved human sperm, oocytes, embryos, red blood cells, monocytes, embryonic stem cells, and hematopoiesis. Vitrified preservation of stem cells, pancreatic islets, etc. At the same time, cryopreservation is relatively more difficult because tissues and organs contain multiple types of cells, as well as large volumes and complex spatial structures.
The human body is composed of about 40 trillion to 60 trillion cells. It is composed of cell groups and intercellular substance with the same or similar shape and function. It is a structural unit composed of a variety of tissues that can perform a (specific) function. That is the organ. The four major tissues of the human body are: epithelial tissue, connective tissue, muscle tissue, and nervous tissue; the structural characteristics of different organs are adapted to their functions, such as: eyes, ears, nose, tongue and other sensory organs, and another example: internal organs Organs heart, liver, lungs, stomach, kidneys, etc.
At 14:30 pm on June 19, 2018, at Shandong Yinfeng Institute of Life Sciences (hereinafter referred to as "Yinfeng Institute of Life Sciences"), a special farewell visit was a quick glance through the glass window, and then another Watching a kind old man being transferred to a liquid nitrogen tank at -196°C. Those who came to visit her were her close relatives - her husband, who had been with her for 53 years, her four children whom she had worked hard to raise, and her little granddaughter, whom she regarded as a treasure, and more than a dozen people.
"Every neuron and process appears to be intact in the brain," said Kenneth Hayworth, president of the Brain Conservation Foundation. Fontana, California, February 10, United Press International reported - A scientific team called "21st Century Medicine" successfully froze a rabbit brain and restored it back at a research institution in California.
In most people's minds, human cryopreservation is both mysterious and unfamiliar. In 2015, news that a female writer from Chongqing had her brain frozen at the Alcor Life Extension Foundation (Alcor) in the United States attracted great attention. This was also the first case of cryopreservation of human brains in China. Now, it is funded by the Shandong Yinfeng Life Science Charity Foundation.
At normal temperature, isolated ischemic tissues and organs will die within a short period of time (from a few minutes to a few hours at most) and cannot be used for transplantation. It is impossible to complete the transplant operation in such a short period of time. Therefore, tissue and organ cryopreservation technology is needed to maintain their activity.
Cryoprotectants are the basis for research on cryopreservation of various human cells, tissues, and organs. Since the discovery of the cryoprotective effect of glycerol in the 1960s, more than 50 drugs or reagents have been used for cryoprotection. In recent years, with the development of vitrification technology, in-depth research on cryoprotectants has attracted the attention of many researchers.
The relationship between the energy difference input to the sample under test and the reference substance and temperature (or time) can be measured through programmable temperature control. The application range is very wide, especially in the research and development, performance testing and quality control of materials, such as glass transition temperature, cold crystallization, phase transition, melting, crystallization, product stability, solidification/cross-linking, oxidation induction period and other research fields.