Autologous Bone Marrow Harvest and Cryopreservation
Bone marrow is obtained by a series of aspirations from the posterior iliac crests, occasionally the anterior iliac crests and/or sternum.
- Sufficient marrow is aspirated to provide a target nucleated cell count of 3.0 x 108/kg of patient. This usually represents approximately 10-15 mL/kg of marrow. More marrow is required if further processing or manipulation is to be performed.
- Normally the patient is under a general anaesthetic. Occasionally a spinal anaesthetic is used.
For full details, refer to procedure 5014 Bone Marrow Harvest Procedure.
For details of bone marrow cryopreservation, see 
Bone Marrow Cryopreservation.
- The harvested marrow undergoes centrifugation for removal of the plasma and buffy coat.
- The buffy coat is then mixed with an equal volume of 20% DMSO (the cryoprotectant dimethylsulphoxide) in autologous plasma and cryopreserved in a controlled rate freezer at a rate of 10C per minute to –800C.
It is stored in the vapour phase of liquid nitrogen at –1960C. Small aliquots of the processed marrow are frozen concurrently and then thawed.
These samples are used to estimate the nucleated cell count and cell viability of the cryopreserved marrow.
- In general, the cryopreserved marrow should contain sufficient cells to reinfuse >1.0 x 108 nucleated cells/kg of patient, with >40% viability. CD34 positive cell count is not routinely performed on autologous bone marrow.
- Samples of marrow are taken at the completion of the harvest and during the processing for microbiological culture to detect any bacterial contamination. (Contamination with coagulase negative staphylococci does not necessarily preclude transplantation).
Topic Code: 9009
