4 Cell Culture Hazards to Avoid

Cell culture work is, of course, the preferred method over traditional animal testing (we all know about the SV40 case), but there are still a number of hazards to take into consideration when working with cell lines. Cell culture work is far from perfect. Here are 4 common hazards to guard against:

1. Mycoplasma Contamination

Depending on which source you read, the prevalence of mycoplasma contamination ranges from around 15 percent to a whopping 80 percent. The effects are essentially unlimited, and it's believed there's still a great deal we're yet to learn about the ways in which mycoplasma can alter cell lines. What we do know, however, is that cell lines across the world have been found to be contaminated with 20 individual species of mycoplasma, with M. orale, M. fermentans, M. hominis, M. hyorhinis, and M. arginini being the most common, accounting for around 90 to 95 percent of all contaminations.

Non-sterile supplies or media that have already been contaminated from an external source may play a role in contamination, but it's believed that we're the ones that are the greatest risk. With the exception of M. hyorhinis and M. arginini, the remainder of the most common species of mycoplasma come from humans, and it's reported that around 80 percent of laboratory technicians are carriers of the bacteria. Unfortunately, there's no miracle solution. Reducing the incidence of contamination is based on an improvement in lab techniques, purchasing media from reputable sources, and testing regularly.

2. Misidentified Cell Lines

There are currently 475 known misidentified cell lines in circulation - a figure that's up from 438 just 2 years ago. Caused by cross contamination, mislabeling, or errors within the lab, these rogue cell lines can have a significant impact upon our work, and there have been many concerns voiced that misidentified cell lines could be severely hindering progress in certain areas, particularly in regard to cancer research. It's reported that at least 15 percent of the human cells we work with do not come from where we think they do, although this figure could be closer to 40 percent.

Cross contamination is one of the primary ways in which misidentified cell lines enter circulation. The HeLa line is currently the most common contaminant, accounting for 29 percent of all human cell line contaminations, including Chang Liver which was believed to be derived from normal liver tissue. T-24 (bladder cancer), CCRF-CEM (human acute lymphoblastic leukemia), and HT-29 (colon cancer) are also common contaminants. Chromosomal analysis and isoenzyme analysis are two of the ways to test cell lines, with the ATCC and International Cell Line Authentication Committee also keeping databases.

3. Antibiotic Use

The use of antibiotics in cell culture work is very much a double edged sword. While it is typically not advised, there are a number of situations in which we find we have very little in the way of alternative choices. One scenario is, of course, the use of selection antibiotics - you may have used Geneticin for eukaryotic cell selection in the past, for example. Antibiotics are also often considered essential in educational research establishments, to protect against microbial contamination and provide a 'buffer' to counteract the effects of substandard practices which are common among interns.

However, there are many concerns regarding the use of antibiotics, most notably that overuse can significantly affect cell biochemistry and alter findings. Studies have found that the overuse of antibiotics can reduce cell growth rate by up to 40 percent, reducing the overall efficiency of cell culture work. There are also concerns that the 'security blanket' effect of antibiotics can encourage poor aseptic techniques in the lab, and that antibiotics can mask the presence of certain bacteria, such as mycoplasma. Antibiotics are sometimes necessary, but they can be a large cell culture hazard.

4. Poor Aseptic Technique

Perhaps the biggest hazard in terms of cell culture work is ourselves and our colleagues. A good aseptic technique in the laboratory is essential if we wish to effectively maintain and preserve cell cultures, protecting them from contamination, such as mycoplasma contamination, reducing the risk of cell misidentification, and protecting the overall value of the cell line. By ensuring high standards of personal hygiene and environmental cleanliness, we're given greater control over the structure, the function, and the behavior of our cell line, reducing the risk of rogue activity from microbial contamination.

The issue, of course, is that we know that 'cell culture material can be maintained aseptically and free of contamination without the need for completely sterile laboratory facilities', and we're playing fast and loose with this information. As we've already discussed, 'cheat' methods such as the use of antibiotics are contributing towards a poor aseptic technique generation, but there are still a number of standard operating procedures that need to be adhered to:

• Keep cells in liquid nitrogen until thawing;
• Store glycerol correctly (in the dark);
• Discard contaminated cells correctly; &,
• Keep your hair tied back!

A VitaScientific we provide a full range of tissue culture solutions including:

• NEST Scientfic Cell Culture Plates, Dishes, Flasks, Pipettes, & Cell Scrapers
• New: Nanosurface ANSF Biomimetic Plates & Dishes, &
• Incubators