Monocyte enrichment from leukapheresis products by using the Elutra cell separator.
BACKGROUND
Dendritic cells (DCs), used in clinical trials for cancer immunotherapy, require processing on an expanded scale to conform to current good manufacturing practice guidelines. This study evaluated a large-scale monocyte enrichment procedure with a commercially available cell separator (Elutra, Gambro BCT) and analyzed the capacity of enriched monocytes to differentiate into DCs.


METHODS
Mononuclear cells were collected in two patients with malignant melanoma and seven healthy donors by leukapheresis. Continuous-counterflow elutriation with the Elutra was performed to enrich and purify monocytes from leukapheresis products. Purity and recovery of enriched monocytes were analyzed by flow cytometry. DCs were generated from the elutriated monocytes and characterized by phenotypic surface marker and stimulatory capacity in an allogeneic mixed lymphocyte reaction.


RESULTS
In the leukapheresis products, the total MNC count was 7.3 x 10(9) +/- 0.7 x 10(9) and the mean percentage of CD14+ monocytes was 16.5 +/- 3.8 percent, which increased to 68.9 +/- 7.4 percent after elutriation with the Elutra. The mean monocyte recovery was 94.3 percent. Elutriated monocytes were successfully cultured into phenotypically and functionally mature DCs.


CONCLUSIONS
These results indicate that the Elutra cell separator allows for fast and easy enrichment of monocytes within a closed system. Furthermore, these monocytes can be differentiated into functionally mature DCs. Compared to plastic adherence and immunomagnetic selection methods, the elutriation procedure is inexpensive, efficient, and very effective.
Kim
Sinyoung
S
Department of Laboratory Medicine, Yonsei Cell Therapy Center, Department of Dermatology, Yonsei University College of Medicine, Seoul, Korea.
Kim
Hyun Ok
HO
Baek
Eun-Jung
EJ
Choi
Youjeong
Y
Kim
Han-Soo
HS
Lee
Min-Geul
MG
D002469:Cell Separation / Q000295:instrumentation / Q000379:methods*; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology; D006801:Humans; D007937:Leukapheresis / Q000379:methods*; D007963:Leukocytes, Mononuclear / Q000166:cytology* / Q000276:immunology; D018950:Lipopolysaccharide Receptors / Q000032:analysis; D015203:Reproducibility of Results
D018950:Lipopolysaccharide Receptors