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

Mononuclear cell recruitment during extracorporeal photopheresis: Partial results of a phase 1/2 randomized clinical trial in multiple sclerosis

BACKGROUND

Despite the routine clinical use of extracorporeal photopheresis (ECP) for the last decades, there has been no sufficient investigation on the intra-apheresis dynamics of mononuclear cells (MNCs).

OBJECTIVE

This research aims to verify the "intra-apheresis recruitment" (IAR) of MNCs, which may be particularly useful in cases with low preapheresis MNC counts.

METHODS

Prospective data of ECP procedures for patients with multiple sclerosis (MS) in the context of the PHOMS study (NCT05168384) were analyzed. ECPs were performed with the use of the Therakos® CellEx® Photopheresis System, and the recruitment factor (RF), collection efficiency 1 (CE1), and fold enrichment (FE) for MNCs, lymphocytes, monocytes, and neutrophils were calculated at various intervals per the approved protocol.

RESULTS

A total of 252 ECP procedures were performed on nine patients with MS, and data from 45 ECPs were analyzed for this study. IAR (RF ≥ 1) of MNCs, lymphocytes, and monocytes was observed in the 93.3 %, 95.5 %, and 88.8 % of the ECP procedures, respectively. CE1 exceeded 100 % for these populations in 13.3 %, 11.1 %, and 24.4 % of ECPs, while FE ≥ 1 for MNCs and lymphocytes was found in all ECPs, and in 97.8 % of ECPs for monocytes. Additionally, RF correlated positively with CE1 for MNCs (r = 0.40, p = 0.006) and lymphocytes (r = 0.43, p = 0.003), as well as with FE for monocytes (r = 0.39, p = 0.01) and lymphocytes (r = 0.48, p = 0.001), further improving collection quality.

CONCLUSIONS

Administering photopheresis with suboptimal MNC counts was plausible and did not worsen the anticipated cytopenias. Moreover, our findings revealed sustained IAR of MNCs in patients with MS who underwent ECP.

A paired study comparing mononuclear cell collection using a new in-line system with an off-line extracorporeal photopheresis apheresis system

BACKGROUND

Extracorporeal photopheresis (ECP) product characteristics are not well established. The aim of this study was to compare mononuclear cells (MNCs) collection using the new Amicus blue (AB) In-line ECP system to our standard Off-line ECP system using the Optia apheresis device and the MacoGenic G2 inactivation system (OM).

STUDY DESIGN AND METHODS

We assessed the ECP products and procedure parameters, patient characteristics, and adverse events for both AB and OM systems in paired patients. Comparisons were made with t-test for paired samples.

RESULTS

Thirteen patients underwent 15 double, paired procedures using both ECP protocols and processing the same blood volume of 4000 mL. Total MNC collected in the product were 51.6 × 108 (95% CI 30.0-73.1) and 42.2 × 108 (95% CI 22.4-62.0) for the AB and OM, respectively (not significant). Both products were also similar regarding volume, MNC concentration, purity, and hematocrit. However, total platelet count (×1011) was significantly lower in the AB products: 0.25 (95% CI 0.15-0.36) versus 1.2 (95% CI 0.9-1.5). The new AB system reduced significantly also the time invested and anticoagulant used per procedure compared with OM, albeit with similar collection efficiency and percentage of MNC captured per procedure. Hypocalcemia was the commonest adverse event with both systems, but it was not severe.

CONCLUSIONS

The new AB system collected MNC products comparable to our current experience with OM, although in a significantly shorter time, with a reduced use of anticoagulant and lower contamination with platelets, which are all valuable advantages of the new system.

Comparison of two inline photopheresis systems: A paired crossover trial

BACKGROUND

Extracorporeal photopheresis (ECP) has been demonstrated as an effective treatment for graft-versus-host disease (GvHD). The inline system was developed by Therakos in 1987. Recently, Fresenius Kabi implemented an integration of cell separator Amicus and a UVA photoactivation device (Phelix), realizing an inline photopheresis system.

STUDY DESIGN AND METHODS

In 2022 we designed a prospective paired crossover trial (NCT05718674) comparing two integrated ECP protocols: Therakos CELLEX and Amicus ECP system. Twenty patients affected by corticosteroid resistant GvHD were submitted to 80 ECP, 40 paired procedures.

RESULTS

All procedures were well tolerated, with no significant differences in procedure duration. CELLEX cell product showed higher granulocytes and platelet content, while Amicus cell product exhibited higher enrichment of lymphocytes, resulting in significantly higher MNC purity (92.9% vs. 84%). A significantly higher granulocytes and platelets absolute content was observed in CELLEX cell products, while Amicus cell products showed a significantly higher number of TNCs and MNCs. Differences in granulocyte and platelet content remained significant even after normalization of the data according to blood volume processed. These findings are confirmed by a statistically significant higher CE2% for CELLEX for granulocytes and platelets along with the lack of significant difference observed for TNCs and MNCs.

DISCUSSION

Our analysis shows differences in the characteristics of the procedure and the cell product. Anyway, both devices are effective for performing ECP procedure, as they collect a cell product suitable for photopheresis. At present, our results represent the first data set comparing two available inline ECP devices.

Evaluating a New Photopheresis System: A Comparison with Two Established Systems on Cell Yield and Collection Efficiency

Background/Objectives: Extracorporeal photopheresis (ECP) is a well-established and efficacious cell therapy for a range of diseases. The objective of this retrospective study was to compare the new Amicus Blue inline system with the Therakos Cellex inline system and the Spectra Optia offline system in terms of collection efficiency, mononuclear cell (MNC) yield of mononuclear cell products (MCPs), processing time and correlation between MCP cell count and peripheral blood count of patients.

METHODS

This retrospective study compared 127 procedures utilizing the Spectra Optia offline system, 93 procedures employing the Amicus Blue inline system, and 81 procedures applying the Therakos Cellex inline system. The MNCs were subjected to flow cytometry analysis for CD45 and CD14 expression in order to ascertain the precise composition of the collected lymphocyte and monocyte fractions.

RESULTS

The Therakos inline system demonstrated the highest MNC collection efficiency (Therakos: 74.42 ± 1.82; Optia: 65.79 ± 1.48; Amicus: 56.32 ± 2.80; p < 0.01). Regarding the content of collected MNCs (×10⁶/kg body weight), the Spectra Optia offline system was superior to the other systems (Optia: 42.69 ± 1.42; Therakos: 31.21 ± 1.66; Amicus: 27.56 ± 1.54; p < 0.01).

CONCLUSIONS

This study represents the first direct comparison of the new Amicus Blue inline system with the two most commonly used ECP systems in the same patient cohort of a single center. The data show that the Amicus Blue inline system collects sufficient MNCs to perform an ECP, but it has a significantly lower CE than the other systems and a significantly lower amount of collected MNCs than the Spectra Optia offline system.

Extracorporeal photopheresis reduces inflammation and joint damage in a rheumatoid arthritis murine model

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammatory reactions and tissue damage in the joints. Long-term drug use in clinical practice is often accompanied by adverse reactions. Extracorporeal photopheresis (ECP) is an immunomodulatory therapy with few side effects, offering a potential and safe therapeutic alternative for RA through the induction of immune tolerance. This study aimed to investigate the therapeutic effects of ECP on RA using a collagen-induced arthritis (CIA) murine model, as well as to explore its immunomodulatory effects in vivo. Additionally, particular attention was given to the significant role of monocytes during the ECP process.

METHODS

A murine model of rheumatoid arthritis was established by administering two injections of bovine type II collagen to DBA/1J mice. ECP, ECP-MD (mononuclear cells were depleted during the ECP), MTX, and PBS treatment were applied to the CIA mice. During the treatment process, clinical scores and body weight changes of CIA mice were closely monitored. After six treatment sessions, micro-CT images of the hind paws from live mice were captured. Ankle joints and paws of the mice were collected and processed for histological evaluation. Spleen samples were collected to measure the Th17/Treg cells ratio, and serum samples were collected to assess cytokine and anti-type II collagen IgG levels. Monocytes and dendritic cells populations before and after ECP in vitro were detected by flow cytometry.

RESULT

ECP therapy significantly attenuated the progression of CIA, alleviated the severity of clinical symptoms in CIA mice and effectively suppressed synovial hyperplasia, inflammation, and cartilage damage. There was an expansion in the percentage of CD3 + CD4 + CD25 + FoxP3 + Tregs and a decrease in CD3 + CD4 + IL17A + Th17 cells in vivo. Furthermore, ECP reduced the serum levels of pro-inflammatory cytokines IL-6 (53.47 ± 7.074 pg/mL vs 5.142 ± 1.779 pg/mL, P < 0.05) and IL-17A (3.077 ± 0.401 pg/mL vs 0.238 ± 0.082 pg/mlL, P < 0.0001) compared with PBS. Interestingly, the depletion of monocytes during the ECP process did not lead to any improvement in clinical symptoms or histological scores in CIA mice. Moreover, the imbalance in the Th17/Treg cells ratio became even more pronounced, accompanied by an augmented secretion of pro-inflammatory cytokines IL-6 and IL-17A. In vitro, compared with cells without ECP treatment, the proportion of CD11b + cells were significantly reduced (P < 0.01), the proportion of CD11c + cells were significantly elevated (P < 0.001) 24 h after ECP treatment. Additionally, the expression of MHC II (P < 0.0001), CD80 (P < 0.01), and CD86 (P < 0.001) was downregulated in CD11c + cells 24 h after ECP treatment.

CONCLUSION

Our study demonstrates that ECP exhibits a therapeutic effect comparable to conventional therapy in CIA mice, and the protective mechanisms of ECP against RA involve Th17/Treg cells ratio, which result in decreased IL-6 and IL-17A. Notably, monocytes derived from CIA mice are an indispensable part to the efficacy of ECP treatment, and the proportion of monocytes decreased and the proportion of tolerogenic dendritic cells increased after ECP treatment in vitro.

Collection efficiency in apheresis

Significant advances in procedural information displayed by current apheresis machines have been made, but analyses of cell collection efficiency (CE) still rely on calculations done by apheresis professionals. Accordingly, understanding CE equations can support the optimization of apheresis techniques and identification of incidents that could impact the procedure's effectiveness. This report summarizes classical and novel CE analyses applied to apheresis exemplified by an actual case of hematopoietic progenitor cell collection. In addition to the apheresis yield and most common CE1 and CE2 formulas, we present the instantaneous and corrected CE, fold enrichment, collection throughput, collection rate and its variants, average inlet rate, classical and adjusted captured cells, recruitment pool, recruitment factor, recruitment coefficient, blood component loss, predictive apheresis yield, and performance ratio calculations. Moreover, the mathematical relationship between these CE equations is also shown, which can be helpful in many apheresis procedures.

Extracorporeal Photopheresis in Graft-versus-Host Disease

Graft-versus-host disease (GVHD) is a major cause of mortality and morbidity following allogeneic hematopoietic stem cell transplantation. Extracorporeal photopheresis (ECP), which exposes mononuclear cells to ultraviolet A irradiation in the presence of a photosensitizing agent, has shown efficacy in the treatment of GVHD. Recent observations in molecular and cell biology have revealed the mechanisms by which ECP can reverse GVHD, including lymphocyte apoptosis, differentiation of dendritic cells from circulating monocytes, and modification of the cytokine profile and T cell subpopulations. Technical innovations have made ECP accessible to a broader range of patients; however, logistical constraints may limit its use. In this review, we scrutinize the development of ECP from its origins to recent insights into the biology underlying ECP efficacy. We also review practical aspects that may complicate successful ECP treatment. Finally, we analyze how these theoretical concepts translate into clinical practice, summarizing the published experiences of leading research groups worldwide.

Increasing the collection flow rate to 2 mL/min is effective and reduces the procedure time in off-line photopheresis

BACKGROUND

Extracorporeal photopheresis (ECP) treatment, mostly based on apheresis technology, is used for immunomodulation in various diseases such as cutaneous T-cell lymphoma, graft versus host disease and other (auto)immune disorders. The aim of this study was to collect high cell counts and purity in shorter procedure times using an ECP off-line system with an increased collection flow rate of 2 mL/min to a target volume of 200 mL buffy coat.

STUDY DESIGN AND METHODS

In this prospective study, data of routinely performed off-line photopheresis treatments were collected and analyzed at the Central Institute for Blood Transfusion & Department of Immunology (ZIB) of the Tirol Kliniken, to assess absolute cell counts and procedure times and to calculate collection efficiencies (CE2).

RESULTS

A total of 22 patients participated in this study. The processed blood volume was 4312 mL, the collection time 120 min, overall procedure time 157 min and the absolute cell counts of treated white blood cells (WBC) and mononuclear cells (MNC) were 5.0 and 4.3 × 109 respectively (median values). The calculated CE2 for WBC and MNC was 21.1% and 58.5%, the proportion of treated MNCs of the total number of MNCs present was 55.0%.

CONCLUSION

The data presented in this study show high therapeutically effective cell counts collected with a high MNC purity within a shorter overall collection/procedure time due to an increased collection flow rate.

Validation of a new automated irradiation system for off-line ECP

Extracorporeal photopheresis (ECP) is a cell therapy originally employed for cutaneous T cell lymphoma and later for GvHD, solid organ rejection and other immunological diseases demonstrating an excellent safety profile. Mononuclear cell (MNCs) apoptosis triggered by UV-A light irradiation in the presence of 8-methoxypsoralene has a key role in priming the cells, ultimately leading to immunomodulation. We report preliminary data about an evaluation of the new automated irradiator device LUMILIGHT (Pelham Crescent srl) for off-line ECP. Fifteen MNCs samples collected by apheresis from 15 adult patients undergoing ECP at our Center were cultured immediately after irradiation along with untreated samples and evaluated at 24, 48 and 72 h timepoints for T cell apoptosis and viability by flow cytometry with Annexin V and Propide Iodidum staining. Post irradiation Hematocrit (HCT), calculated by the device, was compared with that of the automated cell counter. Bacterial contamination was also tested. In irradiated samples after 24-48 and 72 h, the average total apoptosis was 47 %, 70 % and 82 %, respectively, showing a significant difference from untreated samples; residual viable lymphocytes at 72 h were, on average, 18 %. The greatest initiation of apoptosis occurred from 48 h of irradiation onwards. Average early apoptosis of irradiated samples decreased over time (26 %, 17 % and 10 % at 24, 48 and 72 h, respectively). HCT measured by LUMILIGHT was over-estimated, possibly due to the low pre irradiation red blood cell contamination. Bacterial tests resulted negative. Our study showed the LUMILIGHT device to be a valid instrument for MNCs irradiation with good handling and no major technical problems as well as no adverse events in the patients. Our data need to be confirmed in larger studies.

Role of extracorporeal photopheresis in the management of children with graft-vs-host disease

INTRODUCTION

Graft-vs-host disease (GVHD) is a frequent cause of morbidity and mortality in allogeneic stem cell transplants. Extracorporeal photopheresis (ECP) is one of the most accepted second-line treatments, but technical issues of ECP in children might be prohibitive.

MATERIALS AND METHODS

Patients under 18 y of age with corticodependant or corticorefractory GVHD receiving ECP at our hospital were included in this retrospective study. ECP was performed with an in-line system (CellExTherakos) in 2013-2014 and with an off-line system (Spectra Optia) from 2015 onwards. Cumulative incidence curves were obtained to compare ECP efficacy among patients grouped by different baseline, apheresis, and disease characteristics. Significant variables on univariate analysis (Gray's test) were pooled into a multivariate analysis (Fine-Gray proportional hazard regression for competing events).

RESULTS

A total of 701 ECP sessions were performed on 33 patients between October 2013 and December 2021. In total, 97% of the sessions could be executed. In 8% of the sessions an incident was detected, most of them mild and related to catheter dysfunction. With a median follow-up for alive patients of 33.6 mo (range, 8-95), the composite partial and complete response cumulative incidence was 70% (95% confidence interval, 51%-82%) and the median time to maximal response was 2.8 mo (range, 0.25-9.8). Significantly lower response ratios were found in patients with hepatic, gastrointestinal, acute, or severe GVHD. The only variable that influenced response on multivariate analysis was GVHD severity.

DISCUSSION

ECP is feasible, safe, and effective for pediatric patients with corticorefractory or corticodependant GVHD, offering a less toxic and nonimmunosuppressive treatment option.

Mechanisms of Action of Extracorporeal Photopheresis in the Control of Bronchiolitis Obliterans Syndrome (BOS): Involvement of Circulating miRNAs

Clinical evidence suggests an improvement or stabilization of lung function in a fraction of patients with bronchiolitis obliterans syndrome (BOS) treated by extracorporeal photopheresis (ECP); however, few studies have explored the epigenetic and molecular regulation of this therapy. The aim of present study was to evaluate whether a specific set of miRNAs were significantly regulated by ECP. Total RNA was isolated from serum of patients with established BOS grade 1–2 prior to the start and after 6 months of ECP treatment. We observed a significant downregulation of circulating hsa-miR-155-5p, hsa-miR-146a-5p and hsa-miR-31-5p in BOS patients at the start of ECP when compared to healthy subjects. In responders, increased miR-155-5p and decreased miR-23b-3p expression levels at 6 months were found. SMAD4 mRNA was found to be a common target of these two miRNAs in prediction pathways analysis, and a significant downregulation was found at 6 months in PBMCs of a subgroup of ECP-treated patients. According to previous evidence, the upregulation of miR-155 might be correlated with a pro-tolerogenic modulation of the immune system. Our analysis also suggests that SMAD4 might be a possible target for miR-155-5p. Further longitudinal studies are needed to address the possible role of miR-155 and its downstream targets.

Comparison of procedure times and collection efficiencies using integrated and multistep nonintegrated procedures for extracorporeal photopheresis

Background

Extracorporeal photopheresis (ECP) is a blood‐based therapeutic procedure increasingly used for modulation of immune dysregulation in various underlying disease settings. The aim of this study was to compare the procedure times and blood collection efficiencies between the two approaches currently utilized in European centers: the integrated versus the multistep nonintegrated procedures.

Methods

A retrospective data analysis was conducted, comparing treatment data from patients who received ECP therapy at the Central Institute for Blood Transfusion & Department of Immunology (ZIB) of the Tirol Kliniken GmbH, where the integrated and multistep nonintegrated procedures are routinely used in an approximated setup.

Results

During the observation period, a total of 15 patients who were treated with alternating systems on 2 consecutive days were identified. This allowed treatment pair comparisons with minimal interpatient variabilities, similar to a cross‐over design even though analyzed retrospectively. Total average procedure times with the integrated system were 99.3 vs 122.0 minutes with the multistep nonintegrated procedures, respectively. Significant differences were observed for all steps of the ECP procedure: (a) time for buffy coat collection, 66.5 vs 74.7; (b) handling/transfer, 2.8 vs 18.7; (c) irradiation, 20.3 vs 11.7; and (d) reinfusion/handling time, 9.6 vs 16.3 minutes. The calculated collection throughput was 7.79 mL/min for the integrated and 7.84 mL/min for the multistep nonintegrated procedures, and with a white blood cell (WBC) collection efficiency of 34.2% and 21.0%, respectively.

Conclusion

The data presented in this study show a significant shorter overall procedure time and higher WBC collection efficiency for the integrated ECP system.

In situ off-line extracorporeal photopheresis conducted in a real-life situation at a Hemobiotherapy Department in France: A comparison of costs vs on-line procedure

BACKGROUND

The off-line extracorporeal photopheresis (ECP) procedure requires photosensitization in an external cell therapy laboratory as per the French regulatory requirement. This regulation results in higher time and costs compared with the on-line alternative performed entirely at the patient's bedside. Recently, full in situ execution of the off-line procedure has been implemented in the Pitié-Salpêtrière Hospital Hemobiotherapy Department (Paris, France). This report summarizes the center's experience regarding the organizational and costs impacts of this change compared with the on-line procedure.

MATERIAL AND METHODS

ECP was broken down into stages, and several procedures were monitored prospectively in real-life settings. The total costs associated with both procedures were the sum of the fixed costs and variable costs related to all stages of the procedures, nursing-time costs, property costs, and patient-related production loss costs.

RESULTS

Eight off-line ECP and fourteen on-line ECP procedures were monitored during five consecutive days. Procedure duration was not different (median 137.5 vs 154.0 minutes, P = .29). Times and costs associated with nursing were higher but offset by lower fixed costs of the off-line ECP. Total direct costs per procedure associated with using the off-line ECP were significantly lower than those of the on-line procedure (459.6 ± 7.1 EUR vs 953.8 ± 6.5 EUR; P = .0002). Similar results were observed when including the costs of patient production loss.

CONCLUSIONS

As a competitive time procedure, the in situ off-line method proved to be cost-efficient by effectively offering similar patient treatment per year compared with the on-line procedure.

Inline and offline extracorporeal photopheresis: Device performance, cell yields and clinical response

BACKGROUND

Extracorporeal photopheresis (ECP) is an effective treatment for graft-vs-host-disease (GvHD). Photopheresis can be performed in offline or inline method. The first uses a conventional cell separator for collection of mononuclear-cells that are photoactivated by a separate device and manually reinfused; the second one involves a dedicated device performing the entire procedure (collection, photoactivation and reinfusion).

STUDY DESIGN AND METHODS

The objective was to compare the two methods and cell product features to highlight key process, devices performance, and to evaluate ECP clinical response. Patients developing steroid-resistant GvHD underwent ECP as second-line treatment using either inline (Therakos CellEx) or offline system (Terumo BCT Spectra or Optia and UVA PIT system). Data about patients' features, pre-apheresis blood-count, cell product characteristics and clinical response were collected for analysis.

RESULTS

We evaluated 494 procedures performed on 28 patients from April 2018 to March 2019. The offline procedure allows to achieve greater cell yield, it is characterized by larger processed blood volume, longer runtime, and higher ACD consumption. The inline procedure shows shorter runtime, high mononuclear-cells percentage and low percentage of granulocytes in cell product. We observed a significant difference in cell yields between inline and offline system; furthermore we did not find a significant relationship between cell dose and clinical response.

CONCLUSION

Inline ECP is fast, highly automated and productive, making it particularly suitable for ECP treatments. Offline ECP collects high cell yields implying longer procedure and greater operator intervention. Our study did not find a significant relationship between cell dose and GVHD response.

Pilot study of a new online extracorporeal photopheresis system in patients with steroid refractory or dependent chronic graft vs host disease

BACKGROUND

A new protocol has been developed on the Amicus Separator that enables the device to perform online extracorporeal photopheresis (ECP) procedures when used in conjunction with the Phelix photoactivation device and associated disposable kit. The objective of this study was to evaluate the safety and performance of the Amicus ECP System in adult subjects with steroid-refractory or dependent chronic graft vs host disease (cGVHD).

STUDY DESIGN AND METHODS

Eight subjects with mild to severe cGVHD underwent 31 procedures. Subject safety evaluations were performed pre and post procedure and adverse events (AEs) were recorded during treatment and 24 hours after the last procedure. In vitro evaluations of the treated cells included hematology counts and lymphocyte apoptosis, viability and proliferation as measures for ECP procedure validation.

RESULTS

For n = 23 evaluable procedures, median (range) procedure time was 88 (78-110) minutes, during which 2.9 (0.6-4.7) × 10⁹ TNCs (approximately 90% MNCs) were treated and reinfused to the subjects. All subject safety evaluations (vitals, cell counts, plasma hemoglobin and bacterial and endotoxin testing) were within expected ranges. All device or procedure related AEs were mild in nature. After 24 hours in culture, 86 (52-98)% of treated lymphocytes were apoptotic compared to 27 (15-51)% in controls. Inhibition of lymphocyte proliferation was >91% in all procedures.

CONCLUSION

ECP procedures were safely completed in adult subjects with SR-cGVHD treated using the new online Amicus ECP system.

Does Offline Beat Inline Treatment: Investigation into Extracorporeal Photopheresis

Background

Extracorporeal photopheresis is a therapy based on the induction of apoptosis to cells harvested from peripheral blood, followed by direct retransfusion. Currently, there are two approaches: inline procedures, where cell harvesting, 8-methoxypsoralen (8-MOP) incubation, and UV irradiation is performed with a single device, and offline procedures, with collection in one device, followed by 8-MOP incubation/UV irradiation using a second device.

Study Design and Methods

In a prospective crossover study, we compared an inline (Cellex, Therakos) with an established offline procedure (Optia, Terumo, and MacoGenic G2, Macopharma) in 6 patients, focusing on cell composition and apoptosis induction after 24 h. In total, 32 photopheresis treatments per device were performed.

Results

We observed an overall 2-fold higher number of apoptotic "target" cells for each patient with offline treatment. All yields were stratified per patient. Yields were compared as ratio offline/inline for CD3+ (2.5-fold), CD4+ (2-fold), CD8+ (2.8-fold), CD56+ (2.8-fold), CD19+ (1.8-fold), CD15+ (0.5-fold), and CD14+ (2.2-fold) cells. Apoptosis induction was measured after 24 h with Annexin V/7-AAD for early and late apoptosis rates of CD3+ (CD4+, CD8+) and CD56+ cells. CD3+ cells of the inline treatment had an average of 88% (26% early, 62% late) of apoptotic cells compared to 75% (34% early, 41% late) in the offline treatment. Procedure duration ranged from 80 to 100 min inline, with a maximum of 1,500 mL processed blood, and 125-140 min offline, with at least 3,000 mL processed blood, depending on blood flow. Average hematocrit levels of the products were 2.7% inline versus 1.7% offline.

Conclusions

The offline procedure, as established in our department, provides more apoptotic cells for treatment. The increased number of mononuclear cells collected outweighs a slightly reduced apoptosis rate after 24 h in comparison to the inline procedure. Besides this, the final decision for one or the other procedure has to take into account additional aspects, such as peripheral white blood cell count, hematocrit, and weight of the patient, required before apheresis, extracorporeal volume, and, last but not least, overall costs. The final criterion, however, has to be the reported clinical efficacy of the system applied.

Bacterial contamination rates in extracorporeal photopheresis

BACKGROUND

Extracorporeal photopheresis (ECP) is an immunosuppressive treatment that involves leukocyte apheresis, psoralen and UV light treatment, and subsequent reinfusion. Patients treated with ECP are usually immunosuppressed. Bacterial contamination therefore poses a much unwanted risk, but incidence data are lacking.

PATIENTS AND METHODS

We screened all 1922 consecutive ECP procedures scheduled within a roughly 3-year period for eligibility. Those with missing data on ECP method (inline or offline) or type of venous access (peripheral or central) were excluded. ECPs with complete aerobic and anaerobic microbial testing of baseline patient blood samples (n = 1637) and of ECP cell concentrates (n = 1814) were included in the analysis.

RESULTS

A test for microbial contamination was positive for 1.82% of the cell concentrates, with central venous access was the most significant risk factor for the contamination (odds ratio = 19). Patient blood samples were positive in 3.85% of cases, but no patients became septic. Staphylococcus spp. were most abundant, and products with bacterial contamination did not cause side effects after reinfusion. There were no significant differences in contamination rates between inline and offline ECP.

CONCLUSION

These findings stress the importance of sterile procedures and the benefits of using peripheral over central venous access for reducing the risk of bacterial contamination in ECP.

Inline extracorporeal photopheresis: evaluation of cell collection efficiency

BACKGROUND

Extracorporeal photopheresis (ECP) therapy has proved to be an effective and safe treatment for graft-versus-host-disease (GvHD), an important complication after hematopoietic stem cell transplantation. In 2016, we acquired Therakos CellEx, a dedicated inline ECP device to accomplish a significant increase in ECP activity. In literature, we found few data reporting CellEx performance evaluated in terms of collection efficiency to qualify the device. Hence, we decided to collect and analyze our data in order to build a reference in terms of expected results of the procedure. Here we report our data of ECP performed using CellEx in a 12-month period focusing on collection efficiency assessment, as well as procedural and apheretic product characteristics.

STUDY DESIGN AND METHODS

We collected data of patients undergoing ECP from April 2018 to March 2019 using CellEx in order to evaluate collection efficiency.

RESULTS

Between April 2018 and March 2019 we treated 28 adult patients affected by GvHD performing 319 ECP using CellEx. CellEx mononuclear cell product was characterized by high mononuclear cell percentage and low percentage of granulocytes, resulting particularly suitable for ECP treatments. Median collection efficiency for total nucleated cells and for mononuclear cells was 31.2% and 62.3%, respectively.

CONCLUSION

Collection efficiency of CellEx was comparable to that usually obtained by cell separators designed for cell collection and was comparable to that of offline systems. Our results provide a detailed performance evaluation for inline ECP system users.

Automated mononuclear cell collection: a feasibility study employing a new software for extracorporeal photopheresis

BACKGROUND AND OBJECTIVES

Very recently, Fresenius Kabi, improved the software (autoMNC lymphocytes, SW 04.03.08) for mononuclear cells (MNCs) collection with the aim to ameliorate the quality of harvest, employing the automated autoMNC lymphocytes software SW 04.03.09. Herein, we report the results of an observational study evaluating the feasibility of MNCs collection in patients undergoing extracorporeal photopheresis (ECP) at our centre, using the new COM.TEC software 04.03.08c for MNC collection, afterwards integrated in the software 04.03.09, available on the market since November 2018.

MATERIALS AND METHODS

Thirty adult patients (21 males and 9 females) with GvHD, Chronic Lung Allograft Dysfunction or renal rejection, were consecutively enrolled to undergo 1 ECP procedure by the offline technique, according to our internal protocol, processing 1·5 blood volumes. Feasibility of collection was defined as: Hct in collection bag ≤5%, MNCs purity (percentage of MNCs/bag) ≥80%, MNCs collection efficiency (CE2) ≥60%, patient's platelet depletion ≤50%.

RESULTS

Thirty ECP procedures were evaluated. Feasibility (defined by the four parameters previously described) of MNCs collection was observed in 1 out of the 30 harvests analysed. Median Hct in the product was 3·45% (IQR: 2·6-5·0), and median MNCs purity was 97·2% (IQR 89·1-98·6). Median CE2 for MNCs was 21·4% (IQR: 11·9-41·2), and median patient's platelet depletion was 36·2% (IQR 21·9-51·4).

CONCLUSION

The autoMNC lymphocytes software SW 04.03.08c for MNCs collection in ECP setting demonstrated to collect a good quality product in terms of purity and RBC contamination even if the collection efficiency and platelet contamination must be improved.

Efficacy and safety of one-day offline extracorporeal photopheresis schedule processing one total blood volume for treating patients with graft-versus-host disease

BACKGROUND

Extracorporeal photopheresis (ECP) has been increasingly used as a second-line therapy for graft-versus-host disease (GVHD) but there is no consensus regarding the best therapeutic schedule.

STUDY DESIGN AND METHODS

Our offline ECP schedule for treating patients with GVHD was retrospectively reviewed. Patients with acute GVHD were treated on 2 days per week for the first 2 weeks, followed by 1 day per week for 2 more weeks. After the first month of treatment, patients received treatment 1 day every 2 weeks for a minimum of 16 ECP procedures. Patients with chronic GVHD were treated on 1 day per week for 4 weeks followed by 1 day every 2 weeks for a minimum of 14 ECP procedures.

RESULTS

Our series comprises 21 (45%) patients with acute GVHD and 26 (55%) patients with chronic GVHD who received 667 ECP procedures. A median (interquartile range [IQR]) of 1.0 (1.0-1.12) total blood volume was processed. Patients with acute and chronic GVHD received ECP procedures during a median of 49 (IQR, 14-103) and 180 (IQR, 111-274) days, respectively. Mild citrate-induced symptoms were present in 98 (46%) and 232 (51%) procedures in patients with acute and chronic GVHD, respectively. Overall response rate (ORR) and overall survival (OS) were 57 and 38% (95% confidence interval [CI], 17%-59%), respectively, for patients with acute GVHD. For patients with chronic GVHD, ORR and OS were 77 and 61% (95% CI, 18%-87%), respectively.

CONCLUSION

Our new offline ECP schedule for treating patients with acute and chronic GVHD was efficacious and safe.

A standardized methodical approach to characterize the influence of key parameters on the in vitro efficacy of extracorporeal photopheresis

Extracorporeal photopheresis (ECP) is an autologous immunomodulatory cell therapy that consists of the ex vivo collection of mononuclear cells (MNCs), which are irradiated with UVA in the presence of the photosensitizing agent 8-methoxypsoralen (8-MOP) to induce cell apoptosis. This photoactivated cell preparation is then reinfused into the patient. While the clinical benefits of ECP are well-demonstrated, no study has yet characterized the influence of variations in the composition of the cell preparation on the efficacy of ECP in vitro. Here, we describe a standardized methodology for the in vitro assessment of ECP that uses the human lymphoma T-cell line and mimics the clinical procedure. By quantifying cell apoptosis, inhibition of cell proliferation, and 8-MOP consumption, we used this approach to characterize the specific influence of key variables on the cellular response to ECP. We found that (i) increases in hematocrit and plasma concentrations attenuated the cellular response to ECP; (ii) plasma concentration was the only variable tested that influenced 8-MOP consumption; and (iii) the loss of efficacy due to variations in the concentration of certain blood components could be counteracted by modulating the UVA dose. This methodology may enable evaluation of other leukapheresis preparation protocols and better determination of the optimal working parameters for ECP.