Preparation of peripheral blood culture medium
1. The majority of the prepared water culture medium is water, so the quality of water directly affects the quality of the culture medium. According to the Waymouth standard, the resistance of water should be 2 million ohms. Double-distilled or triple-distilled water prepared by a glass distiller in a general laboratory can meet the usage conditions.
2. The culture medium has two kinds, natural and artificial. The general laboratory uses RPMI-1640 powder medium, prepared with double or triple distilled water. NaHCO3 (or HCl) adjusts the pH to 7.2 to 7.4. If the pH exceeds 7.6 or is far below .8, most cells cannot grow. RPMI-1640 is not autoclavable, it needs to be filtered through a 0.22μm pore size filter membrane before use.
3. Calf serum (or fetal calf serum) is often used in serum culture. Serum cannot also be autoclaved. Sterile calf serum needs to be inactivated in a 56 ° C water bath for 30 minutes and stored in a 4 ° C refrigerator for use. The content during preparation depends on the type and time of the cultured cells, generally 10-15%. Because serum components are complex and conditions are not easy to control, serum-free medium can be used.
4. Antibiotics In order to prevent bacterial contamination during the cultivation period, appropriate antibiotics can be added to the culture medium. The general dosage is the same as that of tissue cell culture: kanamycin 100 units / ml, or double antibody-penicillin 100 units / ml, Streptomyces 100 μg / ml.
5. Phytohemagglutinin (PHA)
Cells in the non-proliferative phase cannot produce chromosomes, such as human peripheral blood lymphocytes, but in the process of in vitro culture, under the action of PHA, they can be stimulated to transform into lymphoblasts and enter mitosis. According to the experiment, the splitting peaks were 44-48 hours and 68-72 hours after cultivation.
PHA has two important components, mucopolysaccharide and protein. Mucopolysaccharides promote mitosis and proteins agglomerate. The number of cells activated by PHA increases with its concentration until all immunocompetent cells are activated, but too high a concentration of PHA will cause agglutination, generally 4% concentration is better
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