You must used an antifungal in the media such as flucanzole or miconazole

Hello Yulduz Baltaeva

You haven’t used any antibiotics in the culture medium, which is the right way to culture cells provided you maintain sterile conditions.

Yeast contamination can occur through the airborne route. The ducts in a laminar flow hood can be a potential source of contamination. Laminar flow hoods are designed to maintain a sterile environment by filtering and directing air, but even these systems can be compromised if not properly maintained and checked.

So, besides maintaining sterility, you should also check the HEPA filters, which should be replaced regularly. Check the ducts to see for any signs of damage or contamination. Make sure that the laminar flow hood is functioning properly and providing adequate protection by conducting airflow tests. Utilize UV lights within the hood to further sterilize the work area but remember to remove the UV-sterilized air by proper air circulation.

Best,

Contamination in podocyte cell culture—whether yeast or any other microorganism—is a serious issue and must be addressed immediately and carefully. Here are the steps to follow:

Steps to Handle Possible Yeast Contamination:

1. Confirm the Type of Contamination:

• Examine the culture under a microscope (at 40X or higher): Yeast: Oval cells, smaller than podocytes, often in clusters or showing budding. Bacteria: Very small, fast-moving, spread throughout the medium. Mycoplasma: Not visible under a standard microscope – requires specific testing.

If you're unsure, take an image or send a sample to a microbiology lab for confirmation.

2. Immediately Isolate the Contaminated Culture:

• Move the infected flask or plate to a separate incubator.
• Do not open the container inside the cell culture hood to avoid spreading contamination.

3. Dispose of the Contaminated Culture:

• Once confirmed contaminated, discard the culture completely using a disinfectant (e.g., soak in 10% bleach for at least 20 minutes).
• Clean any tools and surfaces that came into contact with the culture.

4. Check Other Cultures:

• Examine other flasks or plates stored in the same incubator.
• It's best to discard any that show signs of contamination or are suspicious.

5. Disinfect Equipment:

• Thoroughly clean the incubator, biosafety cabinet, and any reusable tools using bleach or 70% ethanol.
• Autoclave pipettes and reusable containers if possible.

6. Investigate the Source of Contamination:

• Check: Media and serum used Filters and pipettes Sterile technique (e.g., glove use, bottle handling)

7. Restore Cultures from a Clean Stock:

• Recover cells from a frozen, verified clean cryovial or order fresh cells from a trusted source (e.g., ATCC).

Thank you so much for all of you!