Combination of Cobe AutoPBSC and Gambro Elutra as a platform for monocyte enrichment in dendritic cell (DC) therapy: Clinical study

Abstract

Monocytes are a common source for generating dendritic cells (DCs). The aim of the present study was to evaluate the efficiency of a platform for monocyte collection and enrichment in a clinical setting. The platform was based on the combination of two semiautomated devices; the Cobe Spectra Auto PBSC for mononuclear cells (MNC) collection followed by counterflow elutriation for monocyte enrichment (Gambro BCT Elutra). Twenty-four patients with various types of epithelial cancer participated in the study. MNC collections were first performed as large volume leukapheresis (LVL). Subsequently, MNC products were processed with an elutriation system for monocyte isolation. LVL resulted in the collection of MNC at a median of 8.1 x 10(9) cells, containing of 31.4% monocytes. A similar efficacy was also shown in patients with lower peripheral blood counts. Elutriation of the MNC product with the Cobe Elutra device resulted in the enrichment of monocytes at a median of 2.7 x 10(9) cells, with a recovery of 80.2% and a purity of 90.7%. These monocytes were then successfully developed into DCs for clinical therapy after in vitro manipulation. These data suggest that the combination of the Cobe Spectra Auto PBSC and the Gambro BCT Elutra is an effective platform for monocyte enrichment in clinical practice according to GCP standards and GMP guidelines, and can be easily implemented in the clinical routine under current DC protocols.

Counter-flow elutriation of clinical peripheral blood mononuclear cell concentrates for the production of dendritic and T cell therapies

“…However, almost all neutrophils were also found in fraction 5 with monocytes and almost all RBCs were in fractions 1 and 2 with lymphocytes. These results are similar to those of other reports which evaluated the same instrument to isolate monocytes from small numbers of PBMC concentrates collected from healthy subjects [7,9,11,20–23], pooled whole blood buffy coat products [8,24] and PBMCs from up to 24 patients with cancer [10,11,16]. …”

“…We found that only about one-third of the products met these criteria, but the quantity of neutrophils among the monocytes could be reduced greatly by density gradient separation with little loss of monocytes. We investigated factors that might influence the neutrophil content of the elutriated monocytes and found that the portion of neutrophils in the monocyte rich fraction 5 was dependent on the quantity of neutrophils loaded into elutriator at the onset of the process; this result is similar to the findings of Chen et al [10]. While we elected to deplete neutrophils from some elutriated monocytes, others have reported that the presence of as much as 20% to 30% neutrophils in elutriated monocytes used to manufacture DCs does not affect the quality of the final mature DC product [24].…”

“…While elutriation has been used to enrich for and separate monocytes [10,16] and lymphocytes [17] for clinical applications, little information is available on the consistency and quality of monocyte and lymphocyte concentrates obtained from PBMC concentrates collected for autologous clinical therapy. We summarized our experience using an automated instrument to elutriate 59 PBMC concentrates, which were processed to enrich for either monocytes to manufacture clinical DC products or lymphocytes to manufacture T cell products for clinical immunotherapy.…”

Potent antitumor effects of combination therapy with IFNs and monocytes in mouse models of established human ovarian and melanoma tumors

“…Elutriated monocytes were obtained from healthy adult donors, after signing informed consent forms, from the Department of Transfusion Medicine at the National Institutes of Health using the Gambro Elutra method [30]. The preparation, in general, contained over 85% monocytes, <10% neutrophils, and <5% lymphocytes.…”