Real-World Practice and Challenges of Donor Lymphocyte Apheresis and Infusion: A Single-Center Experience

Although donor lymphocyte infusion (DLI) is a treatment option after posttransplant immunomodulation, data on donor lymphocyte apheresis (DLA) remain scarce.

We retrospectively analyzed 26 recipients receiving DLI and their related donors (human leukocyte antigen [HLA]-matched, n = 9; haploidentical, n = 17).

The median harvested CD3-positive cell count (CD3) was 6.71 × 10⁷ cells/kg (range, 3.55-19.74). A positive correlation was observed between harvested CD3 and preharvest lymphocyte counts (correlation coefficients = 0.78). In HLA-matched DLI, the median infused CD3 was 1.19 × 10⁷ per cycle and 4.56 × 10⁷ cells/kg in total; in haploidentical DLI, 0.25 × 10⁷ and 0.44 × 10⁷, respectively. The proportion of total infused CD3 relative to harvested CD3 was 26.3% (range, 2.7-100) in HLA-matched DLI and 4.5% (range, 1.4-26.0) in HLA-haploidentical DLI. [Correction added on 21 June 2025, after first online publication: The minimum and maximum value of range for infused CD3 proportion in HLA-matched DLI and HLA-haploindentical DLI has been corrected in this version.] CONCLUSIONS: Our findings reflect real-world practices and underscore the importance of tailoring DLA to donor and recipient characteristics, particularly in light of the increasing use of haploidentical donors.