Repurposing discarded leukodepletion filters as a source of mononuclear cells for advanced in vitro research

In light of advancements in the field of immuno-oncology, the demand for obtaining mononuclear cells for in vitro assays has surged. However, obtaining these cells from healthy donors remains a challenging task due to difficulties in donor recruitment and the requirement for substantial blood volumes. Here, we present a protocol for isolating peripheral blood mononuclear cells (PBMCs) from leukodepletion filters used in whole blood and erythrocytes by apheresis donations at the Hemonucleus of the Barretos Cancer Hospital, Brazil. The method involves rinsing the leukodepletion filters and subsequent centrifugation using a Ficoll-Paque concentration gradient. The isolated PBMCs were analyzed by flow cytometry, which allowed the identification of various subpopulations, including CD4+ T lymphocytes (CD45+CD4+), CD8+ T lymphocytes (CD45+CD8+), B lymphocytes (CD45+CD20+CD19+), non-classical monocytes (CD45+CD64+CD14-), classical monocytes (CD45+CD64+CD14+), and granulocytes (CD45+CD15+CD14-). In our comparative analysis of filters, we observed a higher yield of PBMCs from whole blood filters than those obtained from erythrocytes through apheresis. Additionally, fresh samples exhibited superior viability when compared to cryopreserved ones. Given this, leukodepletion filters provide a practical and cost-effective means to isolate large quantities of pure PBMCs, making it a feasible source for obtaining mononuclear cells for in vitro experiments. SUMMARY: Here, we provide a detailed protocol for the isolation of mononuclear cells from leukodepletion filters, which are routinely discarded at the Barretos Cancer Hospital's Hemonucleus.

Technical validation of a new microfluidic device for enrichment of CTCs from large volumes of blood by using buffy coats to mimic diagnostic leukapheresis products

Diagnostic leukapheresis (DLA) enables to sample larger blood volumes and increases the detection of circulating tumor cells (CTC) significantly. Nevertheless, the high excess of white blood cells (WBC) of DLA products remains a major challenge for further downstream CTC enrichment and detection. To address this problem, we tested the performance of two label-free CTC technologies for processing DLA products. For the testing purposes, we established ficollized buffy coats (BC) with a WBC composition similar to patient-derived DLA products. The mimicking-DLA samples (with up to 400 × 106 WBCs) were spiked with three different tumor cell lines and processed with two versions of a spiral microfluidic chip for label-free CTC enrichment: the commercially available ClearCell FR1 biochip and a customized DLA biochip based on a similar enrichment principle, but designed for higher throughput of cells. While the samples processed with FR1 chip displayed with increasing cell load significantly higher WBC backgrounds and decreasing cell recovery, the recovery rates of the customized DLA chip were stable, even if challenged with up to 400 × 106 WBCs (corresponding to around 120 mL peripheral blood or 10% of a DLA product). These results indicate that the further up-scalable DLA biochip has potential to process complete DLA products from 2.5 L of peripheral blood in an affordable way to enable high-volume CTC-based liquid biopsies.

Inhibition of neutrophil activity in cardiac surgery with cardiopulmonary bypass: a novel strategy with the leukocyte inhibition module

Recently, we showed that the arterial in-line application of the leukocyte inhibition module (LIM) within the heart-lung machine limits overshooting leukocyte activity and cardiac tissue damage. Moreover, significantly better cardiac function was found in an experimental animal model when LIM was used. In the meantime, the first promising clinical data exist. LIM has to be regarded as an essential tool in extracorporeal circulation, in the future, to improve postoperative clinical outcome and to reduce costs. This review summarizes the biological background of LIM and the current experience obtained in experimental models and clinical studies.

Collection of peripheral hematopoietic stem/progenitor cells

OBJECTIVES

Several variables possibly affecting collection of peripheral hematopoietic stem/progenitor cells (PBSC) were evaluated: type of apheresis machine (Amicus version 2.5, Baxter vs Cobe Spectra version 7.0, Terumo BCT), venous access (peripheral vein vs central venous catheter, i.g. CVC), and apheresis regimen (standard vs large volume leukapheresis, i.g. SVL vs LVL) with the objective to increase collection efficacy at the site.

BACKGROUND

Peripheral blood represents the currently preferred source of hematopoietic stem/progenitor cells (HSCs) for transplantation.

METHODS

Data regarding 169 collection procedures performed in healthy donors and patients between January 2008 and December 2011 at the Clinics of Haematology and Transfusiology in St Cyril and Method Hospital in Bratislava (Slovakia) were analysed.

RESULTS

With Cobe Spectra apheresis machine it was possible to process larger blood volumes per procedure with higher CD34+ cell collection efficiency (p = 0.0229) and lower RBC contamination of the harvest than with Amicus (p = 0.0116). On the other hand, Amicus helped to limit PLT contamination of the harvest (p < 0.0001), thus minimizing post-procedural decrease in patient´s PLT count. The highest detected advantage of CVC usage was higher flow rate of procedure, thus processing larger blood volumes per unit of time. Interesting finding was the tendency to lower harvest PLT contamination (p = 0.054). When LVL was performed, significantly higher HSCs yields were collected, even in "poor mobilizers" when the pre-run parameters were low.

CONCLUSION

Management of PBSC collection requires a particular approach in each subject. Institutionally and individually optimized collection may help to improve the transplantation outcome and decrease the financial costs (Tab. 8, Ref. 15).

[Adacolumn apheresis for hepatitis C virus in patients waiting for kidney transplant. Preliminary study]

Hepatitis C virus (HCV) infection occurs much more frequently in the hemodialysis population than in the general population. Patients with chronic kidney disease with persistent HCV infection may develop serious and progressive chronic liver disease, with associated long-term morbidity and mortality related to cirrhosis and hepatocellular carcinoma. Monocytes and macrophages are known to produce extrahepatic breeding sites and spread the disease. Our aim was to lower the levels of macrophages, granulocytes, monocytes, proinflammatory cells and viremia using an extracorporeal device: the Adacolumn ® leukocyte apheresis system (Otsuka). The Adacolumn is a direct hemoperfusion-type leukapheresis device. The column is a single-use (disposable) polycarbonate column with a capacity of about 335 mL, filled with 220-g cellulose acetate beads of 2 mm in diameter bathed in physiological saline. The carriers adsorb ''activated'' granulocytes and monocytes/macrophages that bear Fc and complement receptors. The patients underwent five 1-hour sessions for five consecutive days. The column was placed in an extracorporeal setting with a perfusion rate of 30 mL/min and a duration of 60 minutes. A reduction of viremia was observed in all patients in association with a decrease in cytokine levels and a proportional decrease in immune cells. Although this study investigated responses in a small number of patients, it was shown that the Adacolumn changed the cellular immunity and promoted early viral response.

Efficient removal of platelets from peripheral blood progenitor cell products using a novel micro-chip based acoustophoretic platform

Background

Excessive collection of platelets is an unwanted side effect in current centrifugation-based peripheral blood progenitor cell (PBPC) apheresis. We investigated a novel microchip-based acoustophoresis technique, utilizing ultrasonic standing wave forces for the removal of platelets from PBPC products. By applying an acoustic standing wave field onto a continuously flowing cell suspension in a micro channel, cells can be separated from the surrounding media depending on their physical properties.

Study Design and Methods

PBPC samples were obtained from patients (n = 15) and healthy donors (n = 6) and sorted on an acoustophoresis-chip. The acoustic force was set to separate leukocytes from platelets into a target fraction and a waste fraction, respectively. The PBPC samples, the target and the waste fractions were analysed for cell recovery, purity and functionality.

Results

The median separation efficiency of leukocytes to the target fraction was 98% whereas platelets were effectively depleted by 89%. PBPC samples and corresponding target fractions were similar in the percentage of CD34+ hematopoetic progenitor/stem cells as well as leukocyte/lymphocyte subset distributions. Median viability was 98%, 98% and 97% in the PBPC samples, the target and the waste fractions, respectively. Results from hematopoietic progenitor cell assays indicated a preserved colony-forming ability post-sorting. Evaluation of platelet activation by P-selectin (CD62P) expression revealed a significant increase of CD62P+ platelets in the target (19%) and waste fractions (20%), respectively, compared to the PBPC input samples (9%). However, activation was lower when compared to stored blood bank platelet concentrates (48%).

Conclusion

Acoustophoresis can be utilized to efficiently deplete PBPC samples of platelets, whilst preserving the target stem/progenitor cell and leukocyte cell populations, cell viability and progenitor cell colony-forming ability. Acoustophoresis is, thus, an interesting technology to improve current cell processing methods.

A study of leucocyte removal by the RemoweLL cardiotomy reservoir

BACKGROUND

Cerebral damage is a relatively frequent complication of cardiopulmonary perfusion. Leucocyte activation and lipid microembolisation are among the possible causes. The removal of leucocytes and lipid microparticles from the cardiotomy suction blood could prevent this complication.

METHODS

We studied the properties of a cardiotomy reservoir (RemoweLL, EUROSETS), which contains a filtering layer designed to remove some leucocytes and lipid microparticles. The reservoir was loaded with red cell concentrates or whole blood units, some of them containing hyperlipidaemic plasma. The extent of leucocyte and lipid removal was evaluated with reference to the storage age and pre-filtration absolute values of the products.

RESULTS

On average, the cardiotomy reservoir removed 35-39% of total leucocytes, with a slight preference for neutrophil granulocytes. This device also retained 26-30% of platelets. The efficiency was not influenced by the storage age of the filtered product nor by the total cell load, within the explored range (323x10(6) - 1,345 x10(6) total leucocytes). Lipid (cholesterol, triglycerides) removal was minimal (about 3-6%).

DISCUSSION

The RemoweLL device removed more than a third of the leucocytes from the processed blood. Lipid removal was minimal but the lipid particles in our model (chylomicrons) have a diameter 100-fold smaller than the particles believed to be responsible for clinical effects. This device seems promising and worthy of further studies to document the saturation point of leucocyte removal. On the other hand, lipid removal should be studied in a model more closely resembling the clinical situation in which the device is expected to be used.

Clinical efficacy of two-phase leukocyte filtration in high-risk patients undergoing coronary revascularization with cardiopulmonary bypass

The purpose of this study was to investigate the clinical outcome, inflammatory response and myocardial function in high-risk patients undergoing three different leukocyte depletion strategies. Over a four-month period, forty patients (EuroSCORE 6+) undergoing coronary revascularization were prospectively randomized to one of the four perfusion protocols: Group 1 (N=10): Conventional circuits (ECC) + two leukocyte filters (LG6B, Pall, USA) with the method of two-phase (continuous + strategic) leukofiltration; Group 2 (N=10): ECC + single leukocyte filter with the method of continuous leukofiltration; Group 3 (N=10): ECC + single leukocyte filter with the method of strategic leukofiltration; Group 4 (N=10) CONTROL: ECC without leukocyte filtration. Blood samples were collected at T1: Baseline, T2: On CPB, T3: X-Clamp, T4: Off CPB, T5: ICU24 and T6: ICU48. Perioperative follow-up was thoroughly monitored. Leukocyte counts in double filter and strategic filtration groups demonstrated significant differences at T4 (p < .05 vs. control). TNFalpha levels were significantly lower in Group 1 at T4 and procalcitonin levels at T5 and T6 (p < .05 vs. control). CKMB levels demonstrated well preserved myocardium in double filter group (p < .05 vs. control). Brain natriuretic peptide levels in double filter group were significantly lower at T5 and T6 with respect to Group 2 (p <.05) and control (p <.001). Matrixmetallopeptidase 9 and D-Dimer levels in double filter group were significantly lower at T5 and T6 (p <.05 vs. control).Two-phase leukofiltration is associated with some compound benefit over continuous deployment in high-risk patients. A larger more powerful study than this pilot one is warranted for further evaluation.

Treating ulcerative colitis by Adacolumn therapeutic leucocytapheresis: clinical efficacy and safety based on surveillance of 656 patients in 53 centres in Japan

BACKGROUND/AIM

The Adacolumn selectively depletes granulocytes and monocytes/macrophages, which are thought to be part of the immunopathogenesis of ulcerative colitis. This work aims at evaluating the safety and clinical efficacy of the Adacolumn in patients with ulcerative colitis in large population-based data sets.

METHODS

The Adacolumn post marketing surveillance in Japan was undertaken on 697 patients in 53 medical institutions over 7 years from 29 October 1999 to 28 October 2006. Clinical efficacy and safety data were provided by patients' physicians in the participating institutes.

RESULTS

Safety was evaluated in all the 697 patients and efficacy in 656 patients. At entry, 92% of the patients were on salicylates, 74% on prednisolone and only 9% on immunomodulators. Approximately 40% of patients had severe ulcerative colitis and over 70% had ulcerative colitis that was refractory to conventional medications. There was no serious adverse events; mild to moderate adverse events were seen in 7.7% of the patients. The overall response (remission or significantly improved) was 77.3%; the remission rate based on clinical activity index was 71.1%, while 17.1% remained unchanged and 5.6% worsened. Patients were subgrouped into severe, moderate and mild ulcerative colitis based on clinical activity index (n=578), the response rates were 63.2%, 65.7% and 80.4%, respectively (P<0.001). Endoscopic assessment of efficacy showed very significant mucosal healing, Matts' endoscopic index improved from 3.2+/-0.04 to 2.1+/-0.7 (n=219, P<0.001); reduction in prednisolone dose (P<0.0001); leucocyte count (n=358, P<0.0001) and C-reactive protein (n=314, P<0.0001). Patients who received > or =6 Adacolumn sessions (n=319) did better than patients who received < or =5 sessions (n=188, P=0.004) and multivariate logistic regression analysis revealed that baseline granulocyte count was the strongest predictor of clinical response to Adacolumn (P=0.0191, odds ratio 1.151).

CONCLUSION

This post marketing surveillance provides the largest ever efficacy and safety data on the Adacolumn therapeutic leucocytapheresis in patients with ulcerative colitis. As a non-pharmacologic treatment for patients with active ulcerative colitis most of whom were refractory to conventional drug therapy, the observed efficacy was very significant. Baseline granulocyte count was convincingly an independent predictor of clinical response.

[The effect of leukocyte depletion by filtration on the quality of apheresis platelets]

This study was aimed to investigate the effect of leukocyte depletion by filtration on the quality of apheresis platelets. 20 units of donor apheresis platelets were randomly selected and were preserved with agitation at 20 - 24 degrees C for 24 - 96 hours, then were filtered on polyester flatbed filters. The platelet concentration, mean platelet volume (MPV), volume of apheresis platelets, leukocyte count, pH value, lactate dehydrogenase (LDH) concentration, K(+) concentration and CD62p expression level on surface of platelet membrane, were detected before and after filtration, as well as the rate of leukocyte depletion and platelet loss were calculated. The results showed that the leukocyte count after filtration was remarkably lower than that before filtration (p < 0.001), and the rate of leukocyte depletion was 99.97%. Platelet loss was approximately 8%, and obviously lower than that of the national standard (p < 0.001). MPV, pH value, K(+) and LDH concentration were not significantly different before and after filtration. Compared with platelets before filtration, CD62p expression level after filtration slightly decreased (p > 0.05). CD62p expression on surface of platelet membrane in perfusion fluid obtained from filter plate was obviously higher than that before filtration (p < 0.05). MA of platelet after filtration slightly decreased (p > 0.05). It is concluded that leukocyte and partial activated platelets can be removed efficiently by using polyester flatbed filters, and platelet loss is very low. Filtration does not adversely affect coagulation activity of the platelets in vitro. Apheresis platelets after filtration can fulfil quality requirements to prevent infection of cytomegalovirus and HLA alloimmunization.

Automated CD14+ monocyte collection with the autoMNC program of the COM.TEC cell separator

BACKGROUND

The standard mononuclear cell (MNC) program of the COM.TEC device (Fresenius HemoCare GmbH) showed excellent collection efficiency of CD14+ monocytes. A major disadvantage was high content of residual cells in MNC harvests, which could influence dendritic cell (DC) culture.

STUDY DESIGN AND METHODS

The autoMNC program (COM.TEC) was compared with the standard MNC program (n = 12). Additionally, two cycle volumes (300 mL vs. 450 mL, n = 19) were compared (standard MNC program). Samples were assayed for white blood cells (WBCs), red blood cells (RBCs), granulocytes (PMNs), hematocrit, and platelets (PLTs) on an automated blood cell counter (Sysmex K 4500, TAO Medical). CD14+ cells were analyzed by flow cytometry (FACSCalibur, BD).

RESULTS

The autoMNC program produced 1.33 x 10(9) +/- 0.36 x 10(9) CD14+ cells, 5.60 x 10(11) +/- 0.97 x 10(11) PLTs, and 1.43 x 10(11) +/- 0.37 x 10(11) RBCs. Compared to the standard MNC program, significantly higher PLT yields but lower RBC yields and product volume were harvested. Increasing the CV from 300 to 450 mL dropped the product volume, residual PLTs, and RBCs significantly, whereas WBC and monocyte yields did not change. The WBC predonation counts of donors correlated significantly with monocyte yields.

CONCLUSIONS

The autoMNC program reduced the buffy coat (BC) volume and RBC yields in products compared to the standard MNC program. Increasing the CV (standard MNC program) reduced residual PLTs, RBCs, and the BC volume of MNC harvests. The donor WBC predonation count was a good predictor for the monocyte yield of products.

Selection of Anticoagulants for Leukocytapheresis Therapy in Cases of Active Ulcerative Colitis

BACKGROUND AND AIM

Leukocytapheresis (LCAP) is an extracorporeal leukocyte removal therapy that removes immunocompetent leukocytes from the peripheral blood. Nafamostat mesilate (NM) is the most commonly used anticoagulant for LCAP due to various benefits associated with its use, such as a reduced likelihood of bleeding and minimization of adverse reactions caused by contact between blood and the LCAP device. However, adverse reactions have also been reported with NM administration. We reviewed the safety of anticoagulants other than NM, from the perspective of bradykinin production and the consequent drop in blood pressure during treatment.

METHODS

For each of 10 patients with ulcerative colitis, we used four types of anticoagulants sequentially [NM (30-50 mg), heparin, low-molecular-weight heparin (LMWH) and NM (1 mg), and LMWH] for LCAP. We then examined the changes in the blood bradykinin concentrations from the perspective of adverse reactions during LCAP.

RESULTS

The bradykinin production levels from Cellsorba EX varied, depending on the type of anticoagulant used. NM alone (30-50 mg) or LMWH + NM (1 mg) inhibited bradykinin production, whereas heparin alone or LMWH alone significantly accelerated it. However, an excessive fall of blood pressure was not noted in any of the cases. Use of LMWH alone was frequently associated with pressure elevations in the column.

CONCLUSIONS

Given the significant benefits of minimized adverse reactions of LCAP and of continuation of LCAP, we suggest that an appropriate selection of the anticoagulant(s) may allow safer execution of LCAP.

A new device to study ex-vivo the effects of extracorporeal photochemotherapy on the immune system

Extracorporeal photochemotherapy (ECP) is a medical procedure effective in the treatment of several different T-cell mediated diseases such as cutaneous T-cell lymphoma and Graft-versus-Host Disease. During ECP treatment the patient's blood is processed by means of a cell separator to collect leukocytes (leukapheresis), mostly lymphocytes and monocytes, which are then incubated with the photoactive drug 8-methoxypsoralen (8-MOP), exposed to ultraviolet-A light (UV-A) and reinfused to the patient. It has been suggested that during ECP not only UV-A irradiation but also changes in the environmental condition may be relevant. Although ECP has been shown to have an in-vivo immunomodulatory effect, the mechanisms through which ECP exerts its effect remain elusive. One of the reasons for this incomplete knowledge is the absence of a reliable model for ECP. In order to investigate the effect of ECP on the peripheral immune system, we developed a new device which mimics the complete ECP cycle including blood transit through the cell separator. Peripheral blood samples (50ml) were obtained from volunteers and processed using a peristaltic pump. Peripheral blood mononuclear cells (PBMC) were then collected and treated with 8-MOP and UV-A under the same conditions used for the patients' therapy. Using this strategy we investigated 8-MOP, UV-A and their combined effect on the production of the pro-inflammatory cytokines interferon-gamma (IFN-gamma), interleukine-2 (IL-2) and tumor necrosis factor-alpha (TNF-alpha) in PBMC with and without polyclonal stimulation. We firstly demonstrated that our device does not affect total red and white blood cell counts. After 8-MOP and UV-A irradiation a significant decrease was observed in both activated CD4(+) and CD8(+) T lymphocytes producing IFN-gamma, IL-2 and TNF-alpha. Our findings are in line with those previously obtained in humans after complete ECP treatment, thus suggesting that our newly developed device is suitable for investigating the mechanism of action of ECP ex-vivo.

Blood progenitor cell separation from clinical leukapheresis product by magnetic nanoparticle binding and magnetophoresis

Positive selection of CD34+ blood progenitor cells from circulation has been reported to improve patient recovery in applications of autologous transplantation. Current magnetic separation methods rely on cell capture and release on solid supports rather than sorting from flowing suspensions, which limits the range of therapeutic applications and the process scale up. We tested CD34+ cell immunomagnetic labeling and isolation from fresh leukocyte fraction of peripheral blood (leukapheresis) using the continuous quadrupole magnetic flow sorter (QMS), consisting of a flow channel (SHOT, Greenville, IN) and a quadrupole magnet with a maximum field intensity (B(o)) of 1.42 T and a mean force field strength (S(m)) of 1.45 x 10(8) TA/m(2). Both the sample magnetophoretic mobility (m) and the inlet and outlet flow patterns highly affect the QMS performance. Seven commercial progenitor cell labeling reagent combinations were quantitatively evaluated by measuring magnetophoretic mobility of a high CD34 expression cell line, KG-1a, using the cell tracking velocimeter (CTV). The CD34 Progenitor Cell Isolation Kit (Miltenyi Biotec, Bergisch Gladbach, Germany) showed the strongest labeling of KG-1a cells and was selected for progenitor cell enrichment from 11 fresh and 11 cryopreserved clinical leukapheresis samples derived from different donors. The CD34+ cells were isolated with a purity of 60-96%, a recovery of 18-60%, an enrichment rate of 12-169, and a throughput of (1.7-9.3) x 10(4) cells/s. The results also showed a highly regular dependence of the QMS performance on the flow conditions that agreed with the theoretical predictions based on the CD34+ cell magnetophoretic mobility.

Evaluation of the COM.TEC cell separator in predicting the yield of harvested CD34+ cells

BACKGROUND

This multicenter study was performed with the intention to evaluate the exactness of the predicted CD34+ cell yield calculated by two leukapheresis programs of the cell separator COM.TEC upon the number of donor's circulating CD34+ cells and the blood volume processed.

STUDY DESIGN AND METHODS

Patients and healthy donors (n = 166) received mobilization by chemotherapy and/or granulocyte colony-stimulating factor and underwent CD34+ cell harvest by the leukapheresis programs MNC or RV-PBSC (n = 203).

RESULTS

CD34+ cells were collected by 112 harvests on MNC and by 91 collections on RV-PBSC. The median collection efficiency of CD34+ cells was significantly better for the program MNC than for RV-PBSC (p < 0.001): 67% (31-109) vs. 42% (19-100). The collected CD34+ cell yield was in median more exactly by MNC than by RV-PBSC (p < 0.001): 85% (31-176) vs. 59% (22-110) of the predicted value. Concentrates obtained by RV-PBSC showed in median significantly higher percentages of mononuclear cells (p < 0.001) and CD34+ cells (p < 0.001), 86% (43-99) vs. 56% (25-95) and 1.2% (0.2-14.3) vs. 0.4% (0.1-6.0), and had lower contaminations by erythrocytes (p < 0.001) and platelets (p < 0.001), 13 mL (4-48) vs. 25 mL (5-60) and 1.9 x 1011 vs. 3.1 x 1011, than those harvested by MNC.

CONCLUSION

The significantly better collection efficiency of CD34+ cells and the more exact prediction of the harvested CD34+ cell yield make the leukapheresis program MNC a safe and efficient procedure. However, concentrates collected by RV-PBSC are of a better cellular quality with a significantly higher percentage of mononuclear and CD34+ cells and a lower contamination by erythrocytes and platelets.

Comparison of the Fenwal Amicus and Fresenius Com.Tec cell separators for autologous peripheral blood progenitor cell collection

Peripheral blood progenitor cells (PBPC) are commonly used as a stem cell source for autologous transplantation. This study was undertaken to evaluate blood cell separators with respect to separation results and content of the harvest. Forty autologous PBPC collections in patients with hematological malignancies were performed with either the Amicus or the COM.TEC cell separators. The median product volume was lower with the Amicus compared to the COM.TEC (125 mL vs. 300 mL; p < 0.001). There was no statistically significant difference in the median number of CD34+ cell/kg in product between the Amicus and the COM.TEC (3.0 x 10(6) vs. 4.1 x 10(6); p = 0.129). There was a statistically higher mean volume of ACD used in collections on the Amicus compared to the COM.TEC (1040 +/- 241 mL vs. 868 +/- 176 mL; p = 0.019). There was a statistical difference in platelet (PLT) contamination of the products between the Amicus and the COM.TEC (0.3 x 10(11) vs. 1.1 x 10(11); p < 0.001). The median % decrease in PB PLT count was statistically higher in the COM.TEC compared to the Amicus instruments (18.5% vs. 9.5%; p = 0.028). In conclusion, both instruments collected PBPCs efficiently. However, Amicus has the advantage of lower PLT contamination in the product, and less decrease in PB platelet count with lower product volume in autologous setting.

Mobilization, harvesting and selection of peripheral blood stem cells in patients with autoimmune diseases undergoing autologous hematopoietic stem cell transplantation

Peripheral blood stem cells (PBSC) were mobilized in 130 patients with autoimmune diseases undergoing autologous hematopoietic stem cell transplantation using cyclophosphamide 2 g/m(2) and either granulocyte colony-stimulating factor (G-CSF) 5 mcg/kg/day (for systemic lupus erythematosus (SLE) and secondary progressive multiple sclerosis, SPMS) or G-CSF 10 mcg/kg/day (for relapsing remitting multiple sclerosis (RRMS), Crohn's disease (CD), systemic sclerosis (SSc), and other immune-mediated disorders). Mobilization-related mortality was 0.8% (one of 130) secondary to infection. Circulating peripheral blood (PB) CD34(+) cells/microl differed significantly by disease. Collected CD34(+) cells/kg/apheresis and overall collection efficiency was significantly better using Spectra apheresis device compared to the Fenwall CS3000 instrument. Patients with SLE and RRMS achieved the lowest and the highest CD34(+) cell yields, respectively. Ex vivo CD34(+) cell selection employing Isolex 300iv2.5 apparatus was significantly more efficient compared to CEPRATE CS device. Circulating PB CD34(+) cells/microl correlated positively with initial CD34(+) cells/kg/apheresis and enriched product CD34(+) cells/kg. Mean WBC and platelet engraftment (ANC>0.5 x 10(9)/l and platelet count >20 x 10(9)/l) occurred on days 9 and 11, respectively. Infused CD34(+) cell/kg dose showed significant direct correlation with faster white blood cell (WBC) and platelet engraftment. When adjusted for CD34(+) cell/kg dose, patients treated with a myeloablative regimen had significantly slower WBC and platelet recovery compared to non-myeloablative regimens.

Apheresis products of the Amicus™ and the AS.TEC 204® cell separators are comparable with regard to dendritic cells derived from the mononuclear cell collection

BACKGROUND

In this study, we investigated the quality of autologous mononuclear cells (MNC) collected with two different cell separators using standard MNC-apheresis procedure modalities. MNCs were purified by density gradient centrifugation and cultured according to standard protocols to generate dendritic cells (DC) and 1 x 10(7)/ml immature DCs were pulsed with tumour lysate for 3 days and subsequently characterized by fluorescent-activated cell sorter analysis.

RESULTS

No difference was found in the monocyte content of either apheresis product (P = 0.07) and in the overall yield of MNCs (P = 0.7). Mature DCs as defined by their phenotype revealed also no significant difference: Amicus, 118 x 10(6) cells +/- 91 vs. AS.TEC 204, 128 x 10(6) cells +/- 137 (P = 0.55), respectively, although the contamination with platelets (threefold) and red cells (twofold) was significantly higher in the AS.TEC 204 group (P < 0.05) than in the Amicus group.

CONCLUSION

The Amicus and the AS.TEC 204 are equally capable in providing MNCs for the generation of DCs and the amount of concomitantly collected red cells and platelets had no impact on the final DC yield.

Impact of selective leukocytapheresis on mucosal inflammation and ulcerative colitis: cytokine profiles and endoscopic findings

BACKGROUND

This prospective study assessed the impact of selective leukocytapheresis (SLA) on mucosal inflammation in patients with active ulcerative colitis (UC) by endoscopic investigations and measurement of mucosal cytokine profiles.

MATERIALS AND METHODS

Twenty-eight patients with moderately active UC received 5 SLA sessions with the Adacolumn over 5 consecutive weeks. The Adacolumn leukocytapheresis carriers selectively adsorb granulocytes, monocytes/macrophages, and smaller subsets of lymphocytes (FcgammaR and complement receptors bearing leukocytes). Before and after treatment, mucosal biopsies were obtained from multiple sites in the large bowel. As control, colonic biopsies from 20 patients without bowel inflammation were examined. Mucosal cytokines were measured by enzyme-linked immunosorbent assay.

RESULTS

At entry, the mucosal concentrations of interleukin-1beta (IL-1beta), IL-1 receptor antagonist (IL-1ra), IL-6, IL-8, and tumor necrosis factor-alpha (TNF-alpha) were significantly higher compared with the control group, whereas IL-1ra/IL-1beta ratio was significantly lower. Clinical remission was achieved in 19 (68%) patients. In patients with clinical remission but not in those without remission, the mucosal tissue concentrations of IL-1beta, IL-1ra, IL-6, IL-8, and TNF-alpha significantly decreased, whereas the IL-1ra/IL-1beta ratio significantly increased. Furthermore, endoscopic remission of mucosal inflammation was observed in 14 (50%) patients, which was associated with a decline in mucosal IL-1beta, IL-1ra, IL-6, IL-8, and TNF-alpha and an increase in IL-1ra/IL-1beta ratio.

CONCLUSIONS

Depleting granulocytes and monocytes/macrophages by SLA should mitigate cytokine profiles in the intestinal mucosa and correct an imbalance between pro- and anti-inflammatory cytokines in active UC.

Pilot feasibility studies of leukocytapheresis with the Adacolumn Apheresis System in patients with active ulcerative colitis or Crohn disease

GOALS

Two uncontrolled, multicenter feasibility studies evaluated safety and pilot efficacy of selective granulocyte and monocyte adsorption apheresis (GMA) with the Adacolumn Apheresis System for treatment of moderate-to-severe ulcerative colitis (UC) and Crohn disease (CD) patients refractory/intolerant to conventional pharmacologic therapy.

BACKGROUND

Patients with UC and CD, characterized by elevations in peripheral blood granulocytes, monocytes/macrophages, and proinflammatory mediators, may benefit from reductions in activated granulocytes and monocytes by selective apheresis.

METHODS

Patients underwent weekly Adacolumn sessions for 5 weeks. Pilot efficacy assessments used disease activity index (DAI) for UC (0-12) or CD activity index (CDAI; 0-600) for CD.

RESULTS

Eleven of 15 UC patients completed all 5 treatments. Mean DAI scores fell from 8.4+/-1.3 (baseline) to 5.2+/-2.9 (week 7). Five patients had DAI reductions of > or = 3 points at week 7. Fourteen of 15 CD patients completed all 5 treatments. Mean CDAI scores fell from 308.0+/-76.5 (baseline) to 200.6+/-117.4 (week 7). Nine CD patients responded (CDAI reductions > or = 70 points) at week 7. Remission (CDAI score < or = 150 at week 7) was observed in 6 patients. There were no device-related serious adverse effects.

CONCLUSIONS

Treatment with Adacolumn may be feasible and effective in patients with moderate-to-severe refractory inflammatory bowel disease. Larger sham-controlled studies are ongoing.

Granulocyte and Monocyte Adsorption Apheresis (GCAP) for Refractory Skin Diseases Caused by Activated Neutrophils and Psoriatic Arthritis: Evidence that GCAP Removes Mac-1-Expressing Neutrophils

In the present study, we have shown that granulocyte and monocyte adsorption apheresis (GCAP), an extracorporeal apheresis instrument whose column contains cellulose acetate (CA) beads, is useful for skin diseases attributable to activated granulocytes and psoriatic arthritis (PsA). We assessed the clinical effectiveness of GCAP and investigated the mechanisms underlying the adsorption of pathogenic granulocytes. The effect of GCAP was assessed in 14 patients with neutrophilic dermatoses and 16 with PsA. The mechanisms by which the instrument adsorbs activated granulocytes were investigated using an in vitro mini-column system that mimics the GCAP. Skin lesions and arthropathy improved in 22 of 29 patients (75.9%) and 14 of 18 (77.8%), respectively. Mac-1 (CD11b/CD18) expression on the peripheral neutrophils, increased compared with normal subjects, was reduced by GCAP. In the mini-column system, CA beads adsorbed 50% neutrophils; and adsorption was inhibited significantly by treating plasma with EDTA and blood cells with antihuman CD11b monoclonal antibody. GCAP was useful for treating neutrophilic dermatoses and PsA. GCAP adsorbs Mac-1-expressing neutrophils to the CA beads by the binding of complement component (iC3b) on CA beads and CD11b expressed on activated neutrophils.

Safety and efficacy of extracorporeal granulocyte and monocyte adsorption apheresis in patients with severe persistent bronchial asthma

The Adacolumn is an adsorptive-type extracorporeal device, which is filled with cellulose diacetate beads that selectively adsorb granulocytes and monocytes. Patients with severe persistent asthma experience highly variable continuous symptoms and severe exacerbations in spite of medication based on inhaled glucocorticosteroids. Granulocyte and monocyte adsorption apheresis using extracorporeal circulation through the Adacolumn was performed in nine patients with severe persistent asthma. The extracorporeal circulation through the Adacolumn was performed once a week for 5 weeks. We were able to perform this therapy without any severe adverse effects in all patients, although one patient complained of general fatigue just after the circulations. In six of the nine patients, the increase in peak expiratory flow (PEF) was more than 50 mL/min. The average increase in morning PEF was 23.3% while that in the evening PEF was 26.4% after the therapy. This therapy was not harmful for patients with severe persistent asthma. A placebo-controlled study will be desired to evaluate the efficacy of this nonpharmacological strategy accurately.

Complement activation is involved in biological responses to leukocyte adsorptive apheresis

We examined the effects of complement activation on the biological responses of cellulose acetate (CA) beads. Peripheral blood containing the complement activation inhibitor nafamostat mesilate (NM) or heparin was incubated with CA beads in vitro. Thereafter, the fraction of adsorbed granulocytes as well as the generation of complement activation fragments (C3a and C5a) and interleukin 1 receptor antagonist (IL-1ra) were measured. Granulocyte adsorption, complement activation, and IL-1ra release were significantly inhibited in the presence of NM. Adsorption was significantly increased onto CA beads pretreated with plasma containing heparin even in the presence of NM and adding C3a or C5a enhanced IL-1ra release. These results suggested that bound complement fragment (e.g., C3b) on CA beads plays a central role in granulocyte adsorption to CA beads and that C3a and C5a augment the release of anti-inflammatory substances. We therefore conclude that complement activation is involved in these biological responses of leukocyte apheresis.