Dear Amalia Kotsifaki,

How long can I safely preserve tissue samples at 4°C without compromising cell viability and functionality?

For best results, you may use the tissue samples within 24 hours. If you are unable to work on the tissues immediately, you may store the tissues in sterile culture medium at 4 degree C until use. You may successfully isolate cells from tissue samples stored at 4 degree C up to a maximum of 24-48 hours. Please note the longer the time from surgery to culture, the more the tisue samples are likely to deteriorate. Tissue samples used to generate primary cultures cannot be stored long-term, unlike the tissues used to extract RNA/DNA, which can be stored at -80 degree C using special preservatives.

Are there specific preservation media or additives you recommend for maintaining tissue integrity during this period?

There are no specific preservative media to maintain the integrity of the tissue samples when stored at 4 degree C except the sterile culture medium. Although most surgical specimens are sterile when removed, problems may arise with subsequent handling. Therefore, additives in the form of antibiotic/antimycotic should be added to the culture medium to prevent contamination. Wash the tissues thoroughly well in the medium containing antibiotic/antimycotic at the start of the procedure.

What methods or assays can I use to assess the viability of the cells after preservation?

You may apply simple method like cell counting using viability dyes such as trypan blue or Calcein-AM to check for the percentage of viable cells.

Best.