A paired trial comparing mononuclear cell collection in two machines for further inactivation through an inline or offline extracorporeal photopheresis procedure

Abstract

BACKGROUND Extracorporeal photopheresis (ECP) is an effective treatment. However, protocols differ widely, and some questions, such as the number of cells to be collected or the number of ECP treatment days per treatment cycle, are still unsolved. The aim of this study was to compare a multistep (offline) (Spectra Optia and Macogenic G2) against an integrated (inline) ECP system (Therakos Cellex system) with respect to mononuclear cell (MNC) collection. STUDY DESIGN AND METHODS The number and quality parameters of the MNC products collected were evaluated together with some machine parameters, such as collection time. Comparisons were made through paired sample analysis with the t test. RESULTS Fourteen patients underwent 15 double‐paired procedures using both ECP protocols. The average MNC collected in the multistep procedure was 77.4 × 108, four times more than in the integrated procedure (18.5 × 108). MNC purity (84.4% vs. 63.8%) and enrichment (27.9 vs. 5.9) in the product collected were also higher in the multistep procedure. The whole ECP time was higher in the multistep than in the integrated procedure (272 vs. 106 min), but the calculated time to collect 25 × 108 MNCs in the multistep was shorter compared with the one‐step procedure (77.8 vs. 172 min). All these differences between the two protocols were statistically significant. CONCLUSIONS These two ECP protocols are different with respect to MNC collection and length of procedure. Some unresolved questions, such as the better MNC dose to inactivate or the number of consecutive days that ECP should be performed for optimal clinical efficacy, require further review.

Inline extracorporeal photopheresis: evaluation of cell collection efficiency

“…We observed results aligned with previously reported experiences according to FE and %CC methods: 6.6, 7.4, 6.8 FE for lymphocytes, monocytes, and MNCs, respectively; 19.5, 21.4, 21.0 %CC for lymphocytes, monocytes, and MNCs, respectively (see Table ). We used these methods to compare our data with previously published data even if, in our opinion and confirmed by other authors, these methods are simple but largely influenced by differences in patient characteristics (total blood volume) and by real processed blood volume.…”

“…In literature, non‐standard measurement methods were used to assess CellEx collection efficiency: fold enrichment (FE) and % captured cells (%CC) …”

“…According to other authors, collection efficiency was also assessed using: 1) fold enrichment (FE), the ratio of WBC (or lymphocytes, or monocytes, or MNCs) counts in buffy coat to those in peripheral blood and 2) % captured cells (%CC), the percentage of WBCs (or lymphocytes, or monocytes, or MNCs) collected during leukocytapheresis [(cell count in buffy coat × volume in treatment bag × 100)/(peripheral blood cell count x total blood volume estimated based on height and weight)].…”

“…Since the second half of 2016, according to increasing transplant activity in our institution, ECP procedures increased and we began to use also the inline system CellEx (Mallinckrodt Pharmaceuticals, formerly Therakos Inc.). In literature, we found only few reports about CellEx collection efficiency to qualify the device and to validate the procedure …”

Does Offline Beat Inline Treatment: Investigation into Extracorporeal Photopheresis

“…The upper limit of the processed volume is restricted to 2,000 mL. The inline system collected more granulocytes, as also shown by other authors [23, 24]. Recent findings indicate a promoting role of neutrophils at GvHD onset [25]; however, there is a lack of data on whether apoptotic neutrophils might have any effect in this regard.…”