Measures to protect your cells from mycoplasma contamination
Note
This information is just for reference, operators (users) are solely responsible for how to handle cells and how to prevent mycoplasma contaminations. We do not take any responsibility for the direct or indirect loss, damage and disadvantage that caused by referring to this blog page.
What is mycoplasma
Mycoplasma is bacterium that causes infections in human body. It doesn’t have cell wall.
Mycoplasma is parasitic in eukaryotic cells and features with extremely small genome. Since mycoplasma is extremely small (0.2 – 0.8µm) and doesn’t have cell wall, it is likely to pass through even 0.22µm filter and often contaminate cultured cells in a laboratory.
Mycoplasma is resistant to penicillin and sometimes shows resistance to other antibiotics.
Besides, it is hard to detect it even under the microscope due to its small size, so researchers have difficulty finding that their culturing cells are contaminated with mycoplasma in some cases.
Mycoplasma contamination may cause change in gene expression, cell metabolism, and cell morphology etc. Therefore, research results might be eventually affected.
Contamination source of mycoplasma
Because mycoplasma contamination is difficult to be visually detected,even under microscope, it could spread to other cells without users’ realizing.
In Japan, it is said that more than 95% of mycoplasma contaminations are caused by 6 kinds of mycoplasma listed in the following table.
| Kinds / series / spieces | Host |
|---|---|
| Mycoplasma Orale | Human |
| Mycoplasma Fermentans | Human |
| Mycoplasma arginini | Human / Goat |
| Mycoplasma salivarium | Human |
| Mycoplasma hyorhinis | Pig |
| Acholeplasma Laidlawii | Cow |
Among these mycoplasmas, Mycoplasma hyorhinis, Mycoplasma arginini, and Mycoplasma orale, whose natural hosts are pig, cattle and human respectively, are the major sources of contamination.
Thus, we realized that a lot of mycoplasma contaminations are caused by contaminated serum derived from cow, trypsin derived from pig or improper handling in cell culture.
And then, there is the risk that mycoplasma could spread to healthy cells unintentionally if contaminants remain in the work area after handling contaminated cells.
Prevention of mycoplasma contamination
As mentioned above, it is thought that most of mycoplasma contaminations might be caused by animal-derived materials, and handling non contaminated cells in the contaminated area could spread the mycoplasma to other normal cells.
Mycoplasma orale is often detected in the mouth of human, so the improper behaviors, for example, talking, sneezing and throat clearing, while handling cells could be the cause of Mycoplasma contamination.
Therefore, in order to protect your precious cells from mycoplasma contamination, it is recommended you check regularly whether your cultured and cryopreserved cells are contaminated by mycoplasma or not. Besides, it is important to improve researchers’ skills of handling cells and reduce the risks of mycoplasma contamination caused by improper handling to bring cell-to-cell contamination to a stop.
In the case that your cells are contaminated by mycoplasma, throw away the contaminated cells immediately or remove mycoplasma by using dedicated reagent in order to protect other healthy cells.
Additionally, we recommend using devices which are effective against mycoplasma contamination to reduce the risk of contamination.
In summary, it is assumed that the risks of mycoplasma contamination can be reduced by taking measures in the following order.
- Regularly check whether your cells are contaminated by mycoplasma or not. If it is found out that the cells are already contaminated by mycoplasma, discard contaminated cells or remove mycoplasma with antibiotics that works effectively against mycoplasma.
- Improve researchers’ skills of cell culture to prevent other healthy cells from being contaminated.
- Consider using devices or reagents, for example, FOGACT, MC210 and so on, which can reduce the risk of mycoplasma contamination or remove mycoplasma.
Products for preventing mycoplasma contamination
As mentioned above, periodical check of mycoplasma contamination and improvement in researchers’ skills of cell culture are effective to prevent mycoplasma contaminasion. However, the simplest and most effective method is using new equipment like the protective container for culture flasks that allow culture cells to be placed in separated environment, CO2 incubators with decontamination functionalities or decontamination devices for CO2 incubators.
It must be noted that medium contaminated by mycoplasma could be the source of contamination to other equipment, such as incubator, clean bench, centrifuge, and so on.
So it is important to decontaminate the equipment regularly.
Wiping out cell culture related devices and machines with 70% ethanol or decontamination them with UV lamps is also effective to prevent contamination or remove mycoplasma.
However, there is a chance that the corner and the gap of the equipment cannot be wiped out completely.
Further, becuase the irradiation intensity of UV lamp is decreased by distance, there might be almost no effect in the areas in which UV does not reach enough.
A lot of useful products that can prevent contamination, for example, individual protective containers for culture flasks, mycoplasma removal agent and decontamination equipment for incubators are available and distributed by WAKEN B TECH
MyCanister
MyCanister is useful for protecting your precious cells from contamination by isolation the cell culture flasks from the outer environment. It also contibutes to reducing the risk of crosss-contamination during cell culture in an incubator or transportation.
MyCanister can keep its inside clean with the high-performance filter so it reduces contamination risks effectively.
FOGACT – Small decontamination device
FOGACT is the device which can decontaminate lab equipment such as CO2 incubator, clean benches and so on by generating decontaminant “dry fog” of peracetic acid agent “Spore-Clentz”.
Since the diameter of dry fog particle is extremely small (≦6µm), the equipment surfaces do not get wet by decontaminant, and you do not need to wipe them out after decontamination by FOGACT.
The device is so small and light that it can be placed in incubators, clean benches, centrifuges and so on, and you can decontaminate inside of them.
The suitable decontamination time is automatically calculated according to device type to be decontaminated, so anyone can perform decontamination easily by using this device. Typically, the decontamination process for CO2 incubator is completed within just an hour and for a safety cabinet, within 2 hours.
BI (Biological Indicator) is also available, you can check whether the decontamination can be performed successfully.
WATERBAG
WATERBAG is a unique product.
It is intended to be used for humifying CO2 incubator chambers and made of polyethylene and Dupont Tyvek.
Taking advantage of Tyvek’s special properties that it is impervious to microorgaisms while it is pervious to air and humidity, WATERBAG was developed as a safe humidification tool that can be substituted for water tray.
By using WATERBAG, you can reduce contamination risks from humidification water and protect your cells from these risks.
*WATERBAg is very useful tool, but it cannot be used with CO2 incubators that have a dew point in the chamber.
Products for checking mycoplasma contamination
We do not have device and reagents used for checking mycoplasma contamination but many companies distribute similar products, you can find many of the products on the internet.
In the case your cells are already contaminated by mycoplasma…
No matter how strictly you manage the cell culture environment and cells, the risk of contamination cannot be eliminated as long as cell culture is handled by human beings.
If there is a possibility that your cells are contaminated by mycoplasma, separate them immediately and discard them or start disinfection process as soon as possible.
If your cells are precious and you cannot throw them away, you should immediately start disinfection process by using anibiotics.
MC-210
MC-210 is one kind of quinolone antibiotic and developed by Dainippon Sumitomo Pharma Laboratory and it is effective against many kinds of mycoplasmas.
It usually takes only 1 week to remove mycoplasma from cells by using MC-210 at 0.5μg/mL (The concentration can be increased up to 1.0ｇ/ｍL).
Further, there is no damage to cultured cells and, thus, MC-210 removes mycoplasmas effectively.
Notice:
Using MC-210 for preventive purpose could allow mycoplasmas to have resistance to antibiotics. Do not use MC-210 for preventive purpose, only use when cells are contaminated by mycoplasmas.
At last
There are many causes of mycoplasma contamination, for example, lack of cell handling skills, inefficient decontamination, failure in using lab equipment, air conditioner, room environment and so on.
It is so difficult to eliminate the risks of contamination.
But you can reduce the risks by periodical check of contamination and disinfection of contamination source, skill training, use of equipment and devices that are effective against contamination.
We recommend you regularly check whether your cells are contaminated by mycoplasma or not, and take proper measures to remove mycoplasmas if you confirm your cells are contaminated.
We carry a wide variety of products that are useful and helpful for cell culture processes.
Please see our product pages through the following button for more detailed information about the products.