Technical Topics of Interest
Cell culture contamination has been a major concern for researchers since cell culture was introduced in the early 1900’s. One particular villain to the field of in vitro research has been endotoxin. But what do we really know about it?
Information or Misinformation?
Labels may not always tell the truth. Some labels offer little useful information about the product in the bottle, while some may even seek to mislead a buyer into believing something untrue about that product.
You may be familiar with the terms “traceability” and “origin” in reference to fetal bovine serum (FBS), but how do these topics really impact the use of serum in cell culture? “Origin” is simply the country in which the raw material was collected. “Traceability” refers to the documentation roadmap that connects serum origin to final manufacturing and distribution.
Albumin is one of the most extensively used proteins in biological research today. It acts as a powerful antioxidant in cell culture. It binds, sequesters and stabilizes a variety of molecular species which are often unstable. This acidic, soluble protein has both high- affinity and secondary binding sites, optimizing the roles that fatty acids, metals, disulfides, and other molecules play in cellular metabolism.
With all of the choices for bovine serum albumin (BSA) available, you may be wondering what the differences are and which product is right for your application.
What is Heat Inactivation?
The practice of heat inactivating serum was originally developed when only serum from adult animals was available for cell culture. Adult serum contains various immune factors, particularly serum complement, which may inhibit or destroy cells under certain conditions.
Tried and True?
The majority of those who heat inactivate serum products for cell culture probably do not consider whether or not this step is still desirable; they are simply following an original protocol. At one time, heat inactivation was considered necessary because of concerns over possible contaminants in serum. Things have changed. Today, many feel that exposing serum to heat degrades valuable biomolecules, such as growth factors, vitamins, and amino acids–and is no longer generally advisable.
The most important question is, “will precipitates in serum cause harm to my cells?” The answer to this question is no. Serum is an excellent supplement for cell culture media because it contains many of the components necessary for cell growth (proteins, electrolytes, lipids, minerals, vitamins, hormones, and many undefined growth factors). It is important to note specifically what these components are, as each of these has different physiological properties, affecting the appearance of serum and ultimately how Gemini processes and stores serum.
The in vitro culture of animal cells commonly requires a medium rich in nutrients. These nutrients are usually supplied by supplementing a chemically defined medium with animal serum. Serum offers a highly bioavailable complex of proteins and amino acids, lipids and triglycerides, vitamins, inorganic minerals and salts, as well as other minor components and growth factors that promote culture success. Serum may also contain varying concentrations of iron- sequestering heme and mitogenic endotoxin.