Use of various offset settings in the Fenwal Amicus during hematopoietic progenitor cell collection to increase lymphocyte yield and reduce cross-cellular contamination

Introduction: Autologous HPC collection focus has been CD34+ cell yield but product content of other cells is important for patient survival, complications, and resource utilization. Methods: Prospective, paired study examining MNC and RBC offsets (opens and closes collect valve, respectively) was performed using Fenwal Amicus. Lymphocyte, CD34+ cell yields, and cross-cellular contamination were compared using different MNC/RBC offsets and retrospective Spectra data. Results: In paired comparisons, median lymphocyte yields were significantly different only between 0.0/7.0 (17.6 × 10 ⁹) and 1.5/5.0 (14.5 × 10 ⁹) offsets. CD34+ yields were not significantly different between offsets except 1.0/7.0 and 1.5/5.0 (230.3 vs. 156.7 × 10 ⁶). Granulocytes, RBC, and PLT were significantly greater with higher RBC offset. Comparing all offsets, 1.5/5.0 collected fewer lymphocytes, granulocytes, RBC, and PLT. 1.5/6.0 offsets collected more lymphocytes than 1.5/5.0 but fewer granulocytes and RBC than others except 1.5/5.0. For 1.5/6.0 offsets, PLT content was higher than 1.5/5.0, equivalent to the other offsets, and less than Spectra. CD34+ yields for 1.5/6.0 offsets were equivalent to others except 1.0/7.0. Manufacturer's default (2.3/6.8) collected equivalent lymphocytes and CD34+ to all offsets (except 1.0/7.0) and Spectra. Cross-cellular contamination was higher than 1.5/5.0 and 1.5/6.0 but equivalent to others with more RBC and fewer PLT than Spectra. Conclusion: For maximum lymphocyte yield and minimum contamination, 1.5/6.0 offsets appear optimal. For minimum lymphocyte yield and contamination, 1.5/5.0 offsets would be preferred. Manufacturer's default has CD34+ cell and lymphocyte yields similar to 1.5/6.0 with greater contamination. Amicus can achieve lymphocyte and CD34+ yields similar to Spectra but has significantly less PLT removal.