How Are Stem Cells Collected from Bone Marrow? What Families Need to Know
The bone marrow aspiration procedure explained step by step: what happens, how long it takes, what the child experiences, and how cells are processed.
Why Bone Marrow Is the Primary Source
In autologous stem cell therapy for autism, bone marrow is the most commonly used source of mesenchymal stem cells (MSCs). Bone marrow contains a high concentration of these cells, they are well-characterised in terms of their anti-inflammatory and neurotrophic properties, and the collection procedure is safe and well-established in paediatric medicine.
The pelvic bone (posterior superior iliac crest) is the standard collection site: it is accessible, contains abundant marrow, and the procedure at this site carries a low complication rate.
What Happens Before Collection
The child undergoes a pre-procedure assessment including blood count, coagulation function and a general anaesthesia review. Fasting guidelines (typically nothing by mouth for 4–6 hours before the procedure) are provided to the family.
The procedure is performed under general anaesthesia in a properly equipped clinical setting. The child feels nothing during the collection.
The Collection Procedure
The anaesthesiologist confirms the child is safely anaesthetised before the procedure begins. The collection site — the posterior superior iliac crest on one or both sides — is sterilised.
The physician uses a specialised aspiration needle to withdraw marrow fluid. The collection takes approximately 20–40 minutes. The volume collected is calibrated to the child's weight and the target cell count required — typically 10–20 ml of bone marrow per collection point.
The bone marrow itself is not structurally damaged by aspiration. The marrow regenerates naturally, typically within 4–6 weeks.
What Happens to the Cells After Collection
The collected bone marrow is immediately transferred to the GMP-certified laboratory, where it undergoes:
1. Density gradient separation: Isolating the mononuclear cell fraction containing the stem cells
2. Cell counting and viability assessment: Confirming the number of viable cells collected
3. Sterility testing: Ensuring no contamination
4. Quality documentation: Full traceability record from collection through administration
The prepared cells are administered the same day or within a defined window, as cell viability decreases with time outside the body.
The Child's Experience
Under general anaesthesia, the child has no awareness of the procedure. Recovery from anaesthesia typically takes 30–90 minutes. Most children are alert and drinking fluids within a few hours.
The collection site is typically sore for 24–72 hours, similar to a bruise. Most children require only paracetamol-level analgesia during this period. Normal activity — walking, playing — can typically resume within 1–3 days.
Families are provided with written post-procedure care instructions including what to monitor, when to contact the clinical team, and what level of activity is appropriate during recovery.
Adipose Tissue as an Alternative Source
In some cases — particularly very young children or children where anaesthesia time should be minimised — adipose tissue (fat) obtained via a minor lipoaspiration procedure can serve as an alternative cell source. This procedure is also performed under anaesthesia and recovery is similarly straightforward.
The choice between bone marrow and adipose tissue as the collection source is made based on the child's specific profile, age and clinical judgement. Both sources produce cells with documented anti-inflammatory and neurotrophic properties; there are protocol-level differences in the cell populations obtained from each.
Questions Families Commonly Ask
Is general anaesthesia safe for young autistic children? General anaesthesia is routinely used in paediatric medicine for procedures ranging from dental work to surgery. With appropriate assessment, it is safe for the vast majority of children. The anaesthesiology team will review any specific concerns during the pre-procedure assessment.
Can cells be collected without anaesthesia? Not from bone marrow in a young child. Attempting this without anaesthesia would be distressing and counterproductive. The use of anaesthesia is a safety measure, not a risk.
What if insufficient cells are collected? Cell count is assessed immediately post-collection. In rare cases where the target count is not reached, the clinical team discusses next steps with the family.