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Difference between horse serum and FBS? - (Feb/13/2009 )

Does anybody know the difference between horse serum and FBS? If I put too much serum into the cell culture, say 30-40%, what will happen?

Many thanks!! :(


It depends on the cell line you're using and its preference. For example, 3T3 Fibroblasts prefer horse (equine) serum, whereas CHO-K1 much prefer to be cultured in FBS.

Honestly, I have no idea what happens if you add too much to your cells. I've never come across that before.
Too little will affect adherence (for an adherent line).. and given that logic, it would cause a attachment-free line to adhere.... other than that, I'm sorry. I don't know.


Horse serum will have horse (Equus) antibodies in it rather than cow (Bos) antibodies. Horse serum, unless it states otherwise, will have come from an adult animal which means that there will be a larger number of anitbodies present in it, as well as a lower concentration of growth factors. FBS comes from foetal cows (calfs) before they are born and as such is largely free of antibodies and has a high concentration of growth factors from the developing foetus.

Adding too much serum to a culture could cause an imbalance in the electrolyte and growth factor concentrations in the solution, which will result in your cells not being happy, and possibly cause them to grow in unusual ways. It is best not to add too much serum to cultures, 20% is typically the maximum people add commonly.