Frequently Asked Questions
Q. What is the difference between viable cells and nonviable cells?A. Viable cells are cells that are able to grow. Frozen viable cells are cells that have been cryopreserved with a cryoprotectant such as DMSO (dimethylsulfoxide). The cryoprotectant allows the cells to be frozen safely, ensuring that they can be later thawed and grown. Nonviable cells are cells without viability they are "dead". The cells can not be grown.
Q. How long can samples remain viable when stored in liquid nitrogen?
A. Samples can remain stored in liquid nitrogen for years without loss of viability. The Cell Center has frequently revived samples that have been stored for 12 years with a post-freeze viability > 90%.
Q. How many lymphocyte separations have been performed at The Cell Center?
A. The lab has separated over 7,950 blood samples.
Q. How many blood samples have been processed at The Cell Center?
A. The Cell Center has processed over 22,000 blood samples.
Q. What is the success rate for transforming fresh and frozen lymphocytes at The Cell Center?
A. The success rate for transforming fresh lymphocytes is 99% and for frozen lymphocytes, 98%.
Q. How many fibroblasts lines have been established at The Cell Center?
A. Over 300 fibroblast lines have been established at The Cell Center.
Q. Why does the blood clot if it has been collected in a vacutainer containing a preservative to prevent clotting?
A. The blood should be inverted several times to mix the preservative and blood.
Q. Can blood be stored for more than 4 days prior to lymphocyte isolation?
A. No. The likelihood of a good separation is low.
Q. Should blood for lymphocyte separation or transformation be refrigerated?
A. No. Lymphocyte viability will be greatly lowered and cells may be lysed.
Q. Does The Cell Center isolate DNA?
A. No, but another lab within the Genetics Resources Core Facility does. Contact the manager of the GRCF Methods Development Lab, Laura Kasch-Semenza, at 410-614-3830.
Q. Should blood for viable cell isolation be refrigerated?
A. No
Q. Should blood for DNA isolation be refrigerated?
A. Yes.
Q. What is the difference between ACD solution A and ACD solution B?
A. The ACD (acid citrate dextrose) in solution A is concentrated for 8.5 mls of blood. The ACD in solution B is concentrated for 6 mls of blood.
Q. Does it matter if a vacutainer is not completely filled with blood?
A. Yes. From our experience, if an 8.5 ml tube is not filled with at least 4 mls of blood, the cells may lyse because of the concentrated preservative. A 6 ml tube should have at least 3 mls of blood.
Q. What is the latest time blood samples can arrive at The Cell Center on Fridays?
A. Blood samples must arrive at the lab by no later than 2 pm.