How is the donor marrow delivered to the patient in a transplant?

• A. Injected through IV
• B. Ingested orally
• C. Injected into bone
• D. Inhaled as mist

Answer: (A)

Donor marrow is delivered through a vein, typically via a central line or IV, in a way that's very similar to a blood transfusion. The hematopoietic stem cells in the donor material circulate through the bloodstream and migrate to the recipient’s bone marrow, where they engraft and begin producing new blood cells. This IV route is used because it allows cells to travel the circulation and reach marrow sites throughout the skeleton. Other delivery methods—oral ingestion, direct injection into bone, or inhalation—would not reliably get viable stem cells to the marrow and are not used for transplantation.