It is my understanding that FBS (fetal bovine serum) is preferable to calf serum or adult bovine serum for two reasons. The first reason is that FBS contains more growth-promoting hormones, etc. than does calf or adult bovine serum. The second is that FBS contains fewer antibodies than calf or adult bovine serum. This makes perfect sense.
I’m confused about the merits of using or not using “heat inactivation” or irradiation on FBS. It has been mentioned by manufacturers of FBS that heat inactivation is not necessary, since FBS can be filtered through 1.0 micron filters. I’m inclined to believe this. However, this raises some questions regarding use of non heat-inactivated FBS. If FBS is heat inactivated, to what degree are biomolecules degraded? If using heat-inactivated FBS, should it be assumed that ALL biomolecules must be supplemented from another source, or can it be assumed that a sufficient percentage of biomolecules (hormones, vitamins, etc.) will remain biologically active?
Furthermore, if heat-inactivated FBS is used, and a sufficient percentage of hormones, vitamins, etc. remain biologically active, it seems that the ONLY advantage to using FBS rather than calf or adult bovine serum would be that the FBS would contain a greater compliment of growth-promoting biomolecules than would the latter two types of serum (calf and adult bovine). Is this correct?
In other words,
- If heat-inactivated FBS is used in culture, must supplementary biomolecules be added that would not have had to have been added if using non heat-inactivated FBS?
- Under what circumstances could one use calf or adult bovine serum rather than FBS? If used, would calf or adult serum HAVE to be supplemented with growth-promoting biomolecules (because of their lack of presence relative to FBS)? If supplementation isn’t necessary, would it be advisable? Also, I'd assume that heat inactivation MUST be implemented, given the far greater presentation of antibodies and biomolecules related to the complement immune system in calf and adult bovine serum than in FBS. Is this true?