In gene therapy of Adenosine Deaminase (ADA) deficiency, the patient requires periodic infusion of genetically engineered lymphocytes because:
- ARetroviral vector is introduced into these lymphocytes
- BGene isolated from marrow cells producing ADA is introduced into cells at embryonic stages
- CLymphocytes from patient’s blood are grown in culture, outside the body
- DGenetically engineered lymphocytes are not immortal cells
Solution & Step-by-step Explanation
In the gene therapy for ADA deficiency, functional ADA cDNA is introduced into the patient's own lymphocytes. However, because lymphocytes have a finite lifespan (they are not immortal), the patient must undergo periodic infusions of these engineered cells to maintain a functional immune system.