Detailed Instructions: In this task, you are given an abstract of article. Your task is to generate title for this article. Preferred titles are under thirty words.
Q: Hematopoietic stem cell transplantation is associated with a severe immune deficiency. As a result, the patient is at high risk of infections. Innate immunity, including epithelial barriers, monocytes, granulocytes, and NK cells recovers within weeks after transplantation. By contrast, adaptive immunity recovers much slower. B- and T-cell counts normalize during the first months after transplantation, but in particular, T-cell immunity may remain impaired for years. During the last decade, much of the underlying mechanisms have been identified. These insights may provide new therapies to accelerate recovery.
A:
Reconstitution of the immune system after hematopoietic stem cell transplantation in humans