Ask A Scientist: How to Thaw, Handle & Store Frozen Cells

ask a scientist

Thawing frozen immune cell products can be tricky if you don’t take the proper precautions. It’s best to be well versed in thawing, handling and storage techniques before receiving your cells so you can ensure viability and function for your research.

Many customers have similar cell handling questions, so we’ve compiled some of the most frequently asked questions into one post for your reference. Review this list before receiving your next shipment so you can get the most out of your immune cell products.

Thawing Frozen Immune Cells

How are your cells cryopreserved?

We use a solution consisting of 90% phosphate buffered saline, 10% DMSO with 2 g/100 mL (2%) human serum albumin. We first suspend the cells in PBS-human albumin, and then add PBS-albumin-20% DMSO and gently mix the cell suspension. We rapidly dispense the solution into vials and place the vials in an insulated container, which goes into a –80°C freezer for at least 18 hours before we transfer the vials to liquid nitrogen freezer storage.

The exception to the procedure above is that we freeze neutrophils and mouse cells in CryoStor® CS10 from BioLife Solutions.

How are your cells shipped? At what temperature?

We ship our cells on dry ice, which is about –79°C. We can also ship cells in liquid nitrogen vapor, but it is much more expensive, so we only recommend this if absolutely necessary.  

We usually ship orders upon receipt when in stock, so you can expect your shipment the next day. If weather or other shipping delays are predicted, we will hold your shipment to prevent damage in transit.

Can I thaw and then refreeze cells?

While it is possible to refreeze cells, we do not recommend it. To prevent the need for this, we offer most cell products in different vial sizes so you can use only what you need for your experiment with no waste.

If you insist on thawing and refreezing cells:

  1. Thaw the vial
  2. As soon as the ice is gone, mix the vial contents gently
  3. Remove only the volume you need for your experiment
  4. Immediately freeze the remaining contents of the vial in a –75°C freezer in an insulated container

The refrozen cells may have poor viability and function upon the second thaw, so consider this when selecting a vial size from the catalog.

How long will it take to thaw frozen cells?

Temperature and speed are very important factors of successful thawing. The temperature should not exceed 37°C, but we have experienced better results when cells are transferred into warm medium. It is also important to thaw cells rapidly and to remove the DMSO from the cell suspension as quickly as possible.

 

Browse Cryopreserved Cells

 

Handling Immune Cell Products

What media do you recommend for culturing cells?

When it comes to media selection, the answer is an unsatisfying “it depends.” We recommend testing several media in your own lab setting to see how each influences your experimental design.

We’ve experimented with the best medium for culturing human and mouse macrophages.  We also have research from SITC 2018 that explores the impact of culture media on T cell expansion and function.

 

See Detailed Protocols for Methods & Materials

 

Storing Frozen Immune Cells

How do I store cells after receiving them?

Cells should ideally be stored in the vapor phase of liquid nitrogen as soon as you receive them. At liquid nitrogen temperatures, no biologically relevant processes can occur aside from cosmic radiation.

If you don’t have access to liquid nitrogen storage, store your cells in a freezer at –75°C or below. The cells will slowly decline in viability when stored in the freezer, so do not store cells at this temperature for longer than one month.

 

Have More Questions About Cells, Ordering or Custom Requests?

Read more of our FAQs, give us a call at 425-481-4180 (toll free: 866-513-1894) or send an email to tech_support@astartebio.com.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.