Introduction to Stem Cells
Stem cells are primitive cells with the ability of self-replication and the potential to differentiate into various cell types. According to their developmental biological origins, stem cells can be divided into embryonic stem cells (ESC) and somatic stem cells.
Based on their different differentiation potentials, stem cells can be categorized into totipotent stem cells, pluripotent stem cells, and unipotent stem cells.
Biological Characteristics of Stem Cells
① They are non-terminally differentiated cells, maintaining undifferentiated or poorly differentiated characteristics throughout life and lacking differentiation markers;
② Their number and location in the organism are relatively constant;
③ They possess the ability of self-renewal;
④ They can divide and proliferate indefinitely: stem cells can divide continuously for several generations, or remain in a quiescent state for a long period;
⑤ They have pluripotent differentiation potential and can differentiate into various types of tissue cells. In other words, they exhibit plasticity in differentiation and development. Under specific environments, they can be induced to differentiate into developmentally unrelated cell types, and their differentiation is influenced by the surrounding microenvironment [stem cell niche];
⑥ They have slow cycling of division, with the vast majority of stem cells remaining in the G0 phase;
⑦ Stem cells grow in two ways: one is symmetric division, which produces two identical stem cells; the other is asymmetric division. In asymmetric division, one daughter cell retains the characteristics of the parent and remains a stem cell, while the other irreversibly proceeds to terminal differentiation and becomes a specialized functional cell.
Application Fields
Stem cell drugs have broad application prospects, including but not limited to neurodegenerative diseases (such as Parkinson's disease, spinal cord injury), cardiovascular diseases, diabetes, liver diseases, hematological diseases, and skin trauma. Currently, the types of stem cells commonly used in clinical practice mainly include mesenchymal stem cells, hematopoietic stem cells, neural stem cells, skin stem cells, pancreatic islet stem cells, and adipose stem cells.
For a long time, hematopoietic stem cell transplantation has been one of the main treatment methods for patients with malignant hematological tumors. However, in China, hematopoietic stem cells are regulated as organ transplants rather than drugs. Mesenchymal stem cells are the most studied in stem cell clinical research in China. According to data from Boya Stem Cell, as of December 4, 2023, there were 127 registered stem cell research projects in China, among which 93 were related to mesenchymal stem cells.
Notably, although stem cell therapy has a promising future, it still faces challenges such as safety, long-term efficacy monitoring, and treatment costs. Global research institutions and enterprises are continuously advancing clinical trials to explore the therapeutic potential for more diseases, indicating that the field of stem cell drugs will continue to grow and expand in the future, bringing new therapeutic hope to patients.
Process Flow of Stem Cell Drugs
1.Cell Source and Collection
- Sources: Stem cells can be obtained from various tissues such as bone marrow, umbilical cord blood, adipose tissue, or embryos.
- Collection: Stem cell samples are collected through specific methods. For example, stem cells are collected from adipose tissue using aspiration, or hematopoietic stem cells are isolated from donors' blood.
2.Cell Isolation and Purification
- Preliminary treatment: The collected samples undergo preliminary processing to remove unwanted components.
- Isolation: Target stem cells are isolated using techniques such as density gradient centrifugation and immunomagnetic bead sorting.
- Purification: The purity of stem cells is further improved to ensure a high-purity target cell population.
3.Cell Expansion
- Culture medium: A suitable culture medium is selected to provide an appropriate growth environment for stem cells.
- Culture conditions: Large-scale culture is carried out in bioreactors or culture flasks under sterile conditions. Factors such as temperature, pH value, and oxygen concentration need to be controlled.
- Subculture: Regular subculture is performed to maintain cell viability and gradually expand the cell quantity.
4.Quality Control
- Cell identification: Detection of cell surface markers, gene expression analysis, etc., are conducted to ensure they meet expected characteristics.
- Sterility testing: Checks for bacterial, fungal, or other microbial contamination in cells and during the culture process.
- Functional verification: Evaluation of the functional characteristics of stem cells, such as differentiation potential and proliferation ability.
5.Cryopreservation
- Cryoprotectant: Cryoprotectants (such as DMSO) are added to prevent cell damage caused by ice crystal formation.
- Freezing process: A programmed cooling method is used to gradually reduce the temperature until reaching liquid nitrogen storage temperature (-196°C).
6.Formulation and Packaging
- Formulation forms: Stem cells are made into suspensions, lyophilized powders, etc., according to clinical application needs.
- Packaging: Encapsulation using sterile packaging materials, with label information attached, including batch number, expiration date, etc.
7.Transportation and Storage
- Transportation conditions: Ensure appropriate low-temperature conditions are maintained throughout the transportation process.
- Long-term storage: Store in dedicated liquid nitrogen tanks or other low-temperature storage equipment to ensure cell viability.
8.Preparation before Clinical Application
Junyan Bio's Stem Cell Quality Control Products
● Kanamycin ELISA Kit
● Gentamicin ELISA Kit
● Host Cell Residual DNA Sample Preparation Kit (Magnetic Bead)
● Automatic Nucleic Acid Purification Instrument
● Trypsin Like Enzyme ELISA Kit
● BSA ELISA Kit
● Ultra Nuclease ELISA Kit
● Mycoplasma DNA (qPCR) Detection Kit
● Bacteria DNA (qPCR) Detection Kit
● Fungal DNA (qPCR) Detection Kit
● Bacterial & FungalDNA Extraction and Purification Kit (Magnetic Bead)
