| Popis: |
Plasma and serum protein fractions have been investigated as potential sources of protein supplement for animal cell culture media by several workers since the 1950s. The results however have been often confused and sometimes conflicting. Recently using very careful control of the processing conditions, especially temperature and pH, it has been found that it is possible to use Cohn fraction IV as a source of medium supplement although it appears that there is some variation in the properties of Cohn fractions prepared by different manufacturers. This development opens the way to cell culture for the production of proteins for clinical use using a nutrient medium containing proteins exclusively of human origin. While reducing the demands made on down-stream purification the use of these fractions introduces new problems of possible infectious contamination which will make it essential that all cell products produced using these supplements are submitted to an effective virus inactivation procedure. |
