Cytokine analysis can provide excellent “snapshots” into the current state of a biological system. By knowing the levels of various cytokines, cell to cell interaction can be monitored. However, to provide accurate data, the process begins with good practices in sample collection and storage. We will provide some of the basics below, but recommend reviewing “Cytokine assays: an assessment of the preparation and treatment of blood and tissue samples,” available on PubMed.
Collection
When working with cell culture media, it is important to remove the media from the cells, and freeze the media to -80°C as quickly as possible. For serum and plasma samples, a variety of different tubes (Heparin, Citrate, EDTA, etc.) may be used for collection. Regardless of the type of tube drawn, the blood should be spun down and plasma or serum collected as soon as possible after collection. Plasma or serum should then be frozen, ideally to -80°C, as soon as possible. If the blood cannot be separated at the time of collection, tubes should be stored at 4°C until they can be processed – ideally within four hours of collection. To ensure that results are comparable among all of your samples, we highly recommend that you standardize your collection procedure.
Storage
Cytokines are fairly stable for up to two years when in frozen samples, provided that freeze thaw cycles are avoided, and that they are stored at -80°C, as opposed to -20°C. If a -80°C freezer is not available, consider putting your samples inside a styrofoam box with some ice packs to avoid the degradation associated with freeze thaw cycles. Lastly, consider the appropriate number of aliquots to store for each sample – your project may require multiple runs, separate setups, repeated runs, etc. Each time a sample must be thawed and re-frozen, they will degrade slightly.
Shipping
Before shipping your samples, please make sure that you are in contact with a team member. Our staff can guide you through the preparation of your shipment, track its progress, and confirm its safe receipt. If you aren’t in communication with our staff, we will not know if we haven’t received a package, and therefore will not be able to react if the carrier (UPS/FedEx/etc.) does not complete delivery on time.
Please ship your samples on a quantity of dry ice sufficient to keep your samples at -80°C all throughout shipment. We recommend shipping overnight air with either UPS or FedEx, but understand weight and cost limitations. Two-day shipments may also work, but again – ensure a sufficient quantity of dry ice. Note that IATA guidelines must be followed when shipping dry ice via air. Instructions can be found both at FedEx and UPS‘s websites.
We recommend shipping samples Monday through Thursday, for delivery on Friday at the latest. Again, please make sure you communicate with a team member prior to shipping. We are happy to help you with this process.
Submission
The Cytokine Core requires that you include a manifest of sample list with your submitted samples. We highly recommend that this document be typed, so that clerical errors can be avoided. Please include any relevant sample groupings, special handling requirements, or other information that we may need to know on this document.