Evaluation of filtration leucocytapheresis for use in the treatment of patients with rheumatoid arthritis

OBJECTIVES

To evaluate the efficacy of filtration leucocytapheresis (LCP) for rheumatoid arthritis (RA).

METHODS

LCP was carried out three times, with 1 week separating each session, in 25 drug-resistant RA patients.

RESULTS

During each session, 96, 98, 61, 84 and 8% of the granulocytes, monocytes, lymphocytes, platelets and erythrocytes, respectively, that entered the LCP filter were removed. The number of granulocytes, monocytes and lymphocytes in the peripheral blood significantly decreased during each session of LCP. However, there was no significant decrease in the number of circulating blood cells during the study period. On average, 110 x 10(8) granulocytes, 5.23 x 10(8) monocytes, and 20.5 x 10(8) lymphocytes were removed during LCP therapy. Assessment of RA before and after LCP showed a substantial and rapid improvement in the tender joints counts, swollen joint counts, and patient's and physician's assessments. No adverse reactions or complications were noted. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels decreased following LCP, although the change in the latter parameter was statistically insignificant. The concentrations of serum albumin, gamma-globulin, IgG, IgM, CH50 and rheumatoid factor titres did not change during or after LCP. Careful analysis indicated that 16 of 25 patients with RA showed > or =20% improvement following LCP therapy.

CONCLUSIONS

Our results suggest that filtration LCP to remove leucocytes from the peripheral blood exerts an immunomodulatory effect in patients with RA.

Collection of peripheral blood progenitor cells with an automated leukapheresis system

BACKGROUND

Apheresis devices designed for the collection of mature blood elements are being used for the collection of peripheral blood progenitor cells (PBPCs). The collection of PBPCs differs from that of other cells in the rarity of the target cell and in the fact that donors may undergo several days of collection. A consequence of this process may be a depletion of blood cells such as platelets from the blood. The disposable set and operating software for an apheresis device (Spectra, COBE BCT) was modified by the manufacturer to automate the collection of PBPCs and reduce the collection of unwanted blood cells.

STUDY DESIGN AND METHODS

A study was initiated to compare the collection of PBPCs with the new device, the AutoPBSC (version [V]6.0 with AutoPBSC tubing set), and that with the MNC (mononuclear cell) procedure (V4.7 with white cell tubing set), for patients and healthy donors.

RESULTS

Patients whose blood was processed by either theV6.0 orV4.7 procedure achieved the target dose of 5 x 10(6) CD34+ cells per kg of patient weight in similar numbers of procedures, even though the calculated collection efficiency for CD34+ cells using the automated V6.0 procedure was significantly less than that with the V4.7 procedure for both allogeneic donors and patients donating PBPCs. The collection efficiency for platelets was lower with the V6.0 procedure, and components collected in this manner contained fewer platelets. Apheresis by the V6.0 procedure required 30 to 60 more minutes per procedure than apheresis by the V4.7 procedure. Review of engraftment kinetics after transplantation did not reveal any effect of the collection procedure on recipients of either allogeneic or autologous transplants.

CONCLUSION

The collection efficiencies of the V6.0 procedure for both CD34+ cells and mature blood cells are lower than those of the V4.7 procedure. The lower collection efficiency for platelets results in a smaller drop in peripheral blood platelet count after the procedure. The automated features of the V6.0 procedure may simplify PBPC collection, but this procedure requires a longer apheresis.

New technique of leukocytapheresis by the use of nonwoven polyester fiber filter for inflammatory bowel disease

Leukocytapheresis (LCAP) is widely used for the treatment of immunological diseases. We studied a new treatment of LCAP using a nonwoven polyester fiber filter. In a basic study, 30-70% of leukocytes were removed. Also, 30-68% of the leukocyte subsets were removed. Sixteen inflammatory bowel disease (IBD) patients, mainly with ulcerative colitis (UC), were treated by this method. Their cytokine activity was normalized in the filter and in the peripheral blood. Eleven of 12 patients with UC were induced to remission. Four patients with Crohn's disease (CD) exhibited improvement. The LCAP using a nonwoven polyester fiber filter was very efficient for treating the patients with IBD. Also, it will be a very useful treatment for immunological diseases and extracorporeal immunomodulation.

L-arginine, prostaglandin, and white cell filtration equally improve myocardial protection in stressed neonatal hearts

OBJECTIVES

L-Arginine may improve cardioplegic protection by increasing nitric oxide production. However, L-arginine may also be detrimental because it generates the free radical peroxynitrite. It would, therefore, be advantageous if the benefits of L-arginine could be achieved by another means.

METHODS

Twenty neonatal piglets underwent 60 minutes of ventilator hypoxia (inspired oxygen fraction 8%-10%) followed by 20 minutes of ischemia on cardiopulmonary bypass (stress) and were then protected for 70 minutes with multiple doses of blood cardioplegic solution. In 5 piglets (group 1), the cardioplegic solution was not modified; in 5 (group 2), low-dose L-arginine (4 mmol/L) was added; in 5 (group 3), prostaglandin E(1) (alprostadil, 4 microgram/L) was added; and in 5 (group 4), the cardioplegic solution was passed through a leukodepleting filter. Myocardial function was assessed by pressure volume loops and expressed as percentage of control, and coronary vascular resistance was measured with each cardioplegic infusion.

RESULTS

Unmodified blood cardioplegic solution (group 1) was unable to protect the severely stressed myocardium, resulting in depressed systolic function (39% +/- 1%) and preload recruitable stroke work (40% +/- 1%), increased diastolic stiffness (239% +/- 3%), and high conjugated diene production, myeloperoxidase activity, and coronary vascular resistance. In contrast, cardioplegic solutions modified with L-arginine, prostaglandin E(1), or leukodepletion, resuscitated the stressed myocardium, resulting in complete return of systolic function (100% vs 101% vs 101%; P <.001 vs group 1) and preload recruitable stroke work (100% vs 101% vs 101%; P <.001 vs group 1), minimal increase in diastolic stiffness (160% vs 162% vs 160%; P <. 001 vs group 1), and lowered conjugated diene production, myeloperoxidase activity, and coronary vascular resistance (P <.001 vs group 1 for each).

CONCLUSIONS

(1) Unmodified blood cardioplegic solution is unable to protect the severely stressed myocardium. (2) L-Arginine, prostaglandin E(1), and leukocyte filtration all improve myocardial protection equally and appear to work by limiting a white blood cell-mediated injury. This reduces oxygen-derived free radical formation, maintains vascular function, and restores functional recovery. Since L-arginine may be detrimental, surgeons should consider using prostaglandin E(1) and/or a leukocyte filter instead.

The application of two different blood cell separators to harvest CD34+ cells in patients suffering from non Hodgkin's lymphoma

From January 1996 until now, thirty-eight PBSC procedures were carried out on 20 patients suffering from NHL, mobilized by polichemotherapy regimens plus recombinant human Granulocyte-Growth Factor (rhG-CSF). Patients were enrolled in PBSC procedures using Dideco Excel (group A) and Cobe Spectra v.4.7 (group B) blood cell separators. Twelve patients were enrolled in group A (6 males and 6 females, median age 33) and 9 patients in group B (5 males and 4 females, median age 55). The mean White Blood Cell (WBC) and Mononuclear Cells Fraction (MNC) peripheral blood counts were not statistically different in either group and neither were blood CD34+ cell peripheral counts. CD34+ cell peripheral value was predictive of the CD34+ yield while mean values of harvested CD34+ cells were not significantly different. CD34+ cell efficiencies were statistically the same. The CD34+ cell purity of the apheresis harvest was statistically different between the two groups (group A = 3.0+/-2.2%; group B = 1+/-0.9%) p = 0.001. High CD34+ cell yields were observed in both groups which confirms that both blood cell separators are able to harvest hematopoietic progenitor cells from peripheral blood.

Multicomponent collection (MCC) with the latest hemapheresis apparatuses

BACKGROUND

Collection of multiple products including plasma, packed red blood cells (PBRC) and double units of platelets, is increasingly improving donor utilisation and decreasing blood transfusion costs. Total apheresis is the new trend in blood banking and both industry and physicians are progressively expanding their involvement in this field. During 1998, at our hemapheresis unit, we used three new apparatuses for multicomponent collection (MCC). These apparatuses vary in terms of principle, operation and specific capabilities, and thus knowledge of them is essential to match their characteristics with plateletapheresis needs.

STUDY DESIGN

We reviewed all MCCs carried out in 1998 with MCS+, Trima and Excel-Pro cell separators. These apparatuses were evaluated in terms of platelet yield, white blood cell (WBC) contamination, efficiency per minute, platelet activation, and PBRC product quality.

RESULTS

The three machines are compared in the following table [table in text].

CONCLUSIONS

MCC with the new apparatuses is well accepted by donors and personnel. There are no risks for the donors and, excluding ACD reactions and/or vaso/vagal attacks at the beginning of procedures, no severe reaction was seen. The quality and quantity of platelet products are good. When PRBC or a second platelets unit are collected, the cost of the kit is covered by this double product.

Adsorption of proteins from plasma at polyester non-wovens

Polyester non-wovens in filters for the removal of leukocytes from platelet concentrates (PCs) must be platelet compatible. In PC filtration, the adsorption of proteins at the plasma-non-woven interface can be of great importance with respect to the yield of platelets. Unmodified and radio frequency glow discharge (RFGD) treated poly(ethylene terephthalate) non-woven (NW-PET) and two commercial surface-modified non-wovens were contacted with human plasma. Protein desorption by sodium dodecyl sulphate (SDS) was evaluated by X-ray photoelectron spectroscopy (XPS). The desorbed proteins were characterized by gel electrophoresis and immunoblotting. Compared to the commercial surface-modified non-wovens, unmodified and RFGD-treated NW-PETs adsorbed a relatively high amount of protein. Significantly more protein was removed from the hydrophobic NW-PET by SDS than from the hydrophilic RFGD-treated non-wovens. RFGD treatment of NW-PET reduces the reversibility of protein adsorption. Less albumin and fibrinogen were removed from the RFGD-treated non-wovens than from NW-PET. In addition, a large amount of histidine-rich glycoprotein was removed from RFGD-treated non-wovens, but not from NW-PET. The different behaviour of RFGFD-treated non-wovens towards protein adsorption is probably caused by differences in the chemical reactivity of the non-woven surfaces.

The effects of a neutrophil elastase inhibitor (ONO-5046.Na) and neutrophil depletion using a granulotrap (G-1) column on lung reperfusion injury in dogs

BACKGROUND

Activated neutrophils are reported to be closely involved in ischemia-reperfusion injury after lung transplantation. We investigated the beneficial effects of a new recombinant specific neutrophil elastase inhibitor, ONO-5046.Na, and an extracorporeal-type granulotrap (G-1) column on ischemia-reperfusion lung injury, by using an in situ warm lung ischemia model in dogs.

METHODS

Warm ischemia was induced for 3 hours by clamping the pulmonary arteries and veins. The left main bronchus was bisected and reanastomosed prior to reperfusion. The left lung was collapsed for 3 hours. A total of 27 adult mongrel dogs were divided into three groups: the control group (n = 9) treated with a saline vehicle; the ONO group (n = 9), in which ONO-5046.Na was continuously administrated from before induced ischemia and to ending 2 hours after reperfusion; and the G-1 group (n = 9), in which a G-1 column was applied for 90 minutes starting 30 minutes before reperfusion under passive bypass support.

RESULTS

Circulating neutrophils in the G-1 group decreased significantly (p<.05) compared to preischemia, and significantly decreased compared with the other groups after reperfusion. Oxygenation was improved actually and pulmonary vascular resistance was kept lower level after the administration of ONO-5046.Na. The increase of lung weight was significantly ameliorated in both the G-1 and ONO groups. In the histopathological study, lungs from the control group demonstrated diffuse alveolar edema, neutrophil infiltration, massive alveolar exudate and hemorrhage, and thickening of the interstitium. Lungs from the G-1 group showed mild swelling of the alveolar wall and neutrophil infiltration. Lungs from the ONO group showed virtually no abnormalities.

CONCLUSION

This study demonstrated that a neutrophil elastase inhibitor and neutrophil depletion prevented lung reperfusion injury. These treatments may prevent ischemia and reperfusion injury in lung transplantation.

Effects of a leucocyte depleting arterial line filter on perioperative proteolytic enzyme and oxygen free radical release in patients undergoing aortocoronary bypass surgery

BACKGROUND

Proteolytic enzymes and oxygen free radicals released from activated leucocytes contribute significantly to the organ dysfunction associated with cardiopulmonary bypass. Leucocyte depletion during extracorporeal circulation should reduce the release of these toxic compounds and thereby improve postbypass myocardial and pulmonary function. Recently, a leucocyte-specific arterial line filter to achieve leucocyte depletion during clinical perfusion has become commercially available. The aim of this study, therefore, was to evaluate the influence of the leucocyte depleting arterial line filter on proteolytic enzyme release, oxygen free radical release and postbypass pulmonary and myocardial function in patients undergoing bypass surgery.

METHODS

Forty patients undergoing elective aortocoronary bypass surgery were included into this prospective, randomized clinical study, 20 in the leucocyte depletion (LG-6 group, leucocyte-specific arterial line filter) and 20 in the control group (AV-6 group, standard arterial line filter). White cell count, differential white cell count, plasma elastase concentration, plasma malondialdehyde concentration and C-reactive protein were determined before, twice during and immediately after cardiopulmonary bypass, at the end of surgery and 6 and 20 h thereafter.

RESULTS

White cell count, differential white cell count, malondialdehyde and C-reactive protein were not significantly different between LG-6 and control patients. Plasma elastase concentrations were significantly (P < or = 0.03) higher during and immediately after extracorporeal circulation in LG-6 group patients. Need for inotropic support, arterial pO2 after extracorporeal circulation and perioperative CK MB mass and troponin I release were not different between the two groups of patients.

CONCLUSION

The use of a leucocyte depleting arterial line filter is associated with an increased release of the proteolytic enzyme elastase, but does not reliably and consistently achieve effective leucocyte depletion during clinical perfusion. In contrast to previous studies, we could not demonstrate any significant difference in postbypass pulmonary or myocardial function between patients perfused with the leucocyte-specific arterial line filter and control patients. Our data do not support the routine use of a leucocyte depleting arterial line filter during clinical perfusion in patients undergoing elective aortocoronary bypass surgery.

Leukocyte depletion during cardiac operation: a new approach through the venous bypass circuit

BACKGROUND

Leukocyte depletion recently has been introduced for cardiac surgical patients to attenuate leukocyte-mediated inflammation and organ reperfusion injury. We evaluated the feasibility of a new leukocyte depletion method in which systemic leukocyte depletion is achieved through the venous side of the cardiopulmonary bypass circuit under low blood flow.

METHODS

Forty cardiac surgical patients undergoing cardiopulmonary bypass were allocated randomly to a leukocyte depletion group (n = 20) and a control group (n = 20). In the depletion group, leukocyte filtration was achieved with two filter sets located between the venous drainage and the venous reservoir. Leukocyte filtration was commenced after the start of rewarming but before the release of the aortic cross-clamp, and it was driven by a spare roller pump of the heart-lung machine.

RESULTS

All the episodes of filtration went smoothly within a period of 10 minutes and with a blood flow rate of 400 mL/min. The mean leukocyte removal rate calculated at the end of filtration was 69%. Circulating leukocytes were reduced by 38% in the depletion group compared with the control group at the moment of cross-clamp release (4.3x10(9)/L versus 6.8x10(9)/L, p<0.05). The postoperative inflammatory response also was reduced as indicated by less production of interleukin-8 (p<0.05). Clinically, there was no significant difference between the two groups in postoperative PaO2 or pulmonary hemodynamics.

CONCLUSIONS

It is technically feasible to deplete circulating leukocytes through the venous side of the cardiopulmonary bypass circuit with a low blood flow rate. Future studies should focus on the duration and timing of leukocyte depletion to optimize the methodology of leukocyte depletion for cardiac surgical patients.

Effect of leukocytapheresis therapy using a leukocyte removal filter in Crohn's disease

Eighteen patients with active Crohn's disease were treated with one leukocytapheresis session per week for a five-week intensive therapy, decreasing to one leukocytapheresis session per month for five sessions of initial maintenance therapy. Nutritional indices, inflammatory reactions, flow cytometry profiles, and cytokine production were also assessed before and after the intensive and initial maintenance therapy. Nine of the patients (50%) attained remission at the end of the intensive therapy. The nine non-remission patients had exhibited longer periods of suffering and more severely affected sites prior to the therapy. In 14 of 18 patients (77.8%), the nutritional indices, Internal Organization of Inflammatory Bowel Disease (IOIBD) score and Crohn's Disease Activity Index (CDAI) improved from the pretherapy levels, but only the remission group (50%) showed improvement in C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The remission group showed significantly higher pretherapy CD4+ CD45+ cell ratios and interleukin-2 (IL-2) production than the non-remission group, and significantly lower activated cells.

In vitro comparison study of CD63 and CD62P expression after contacting leukocyte filters

CD63 and CD62P have been recognized as platelet activation markers. This study investigated the secretion of these antigens to compare the platelet activation between a newly developed stainless steel leukocyte filter (SSLF) and 7 polyester or polyurethane commercially available leukocyte filters. Flow cytometry demonstrated that the SSLF initiated significantly smaller effects in terms of mean fluorescence intensity of CD63 (p<0.03) and of the amount of CD62P expressing platelets (p<0.002) compared to the polyurethane filters. However, there was no statistical difference between the SSLF and polyester filters. The result of this study suggests that the SSLF caused less platelet activation than the polyurethane filters and has biocompatible characteristics comparable to the currently available polyester filters. Stainless steel was selected because of its physicochemical conductivity. With these results, further evaluation of the SSLF will be continued in an attempt to develop an active immunomodulator using this unique characteristic.

Basic clinical study of an easy and effective leukocytapheresis by the use of nonwoven polyester filter

Leukocytapheresis (LCAP) is widely used for the treatment of immunological diseases. We studied a new treatment of LCAP using a nonwoven polyester filter. In a basic study, 30-70% of the lymphocytes were adsorbed. Also, 30-68% of the lymphocyte subsets were removed. This method was applied to 2 patients with corticosteroid-resistant active ulcerative colitis. Erosion, edema, bleeding, ulcer formation, and stenosis of the colon were almost completely repaired after 6 LCAP treatments. LCAP using a nonwoven polyester filter will be a very useful treatment for immunological diseases and extracorporeal immunomodulation.

[Anaphylaxis in a myelodysplastic syndrome patient during platelet transfusion with a leukocyte-reduction filter]

A 77-year-old woman with myelodysplastic syndrome required platelet transfusion. However, she complained of facial flushing and dyspnea immediately after the initiation of an infusion of platelet concentrations (PC) utilizing a Pall PL-PXL8H filter with a negatively charged surface. The same symptoms recurred following a transfusion of washed PC with saline. However, an infusion utilizing a Sepacell PLX5A-W with a positively charged surface caused no problems. Furthermore, the patient demonstrated the same adverse reaction after administration of prostaglandin F2 alpha. This case suggested that special caution is warranted when patients who have an allergic history receive PC infusions through leukocyte-reduction filters with negatively charged surfaces.

Distribution of mobilized progenitor cells in the buffy coat of the haemonetics MCS3p cell separator: a study to optimize the collection of progenitors by leukapheresis

Hematopoietic progenitor and stem cells for transplantation can be mobilized into the circulation and collected by leukapheresis. In this procedure, the leukocytes are distributed in the buffy coat along a density gradient, and the composition of the final product depends on which layer was collected. For the Haemonetics MCS3p Cell Separator, the manufacturer recommended starting the progenitor cell collection at a light transmission of 30%-40% (compared with plasma) and continue it for 40-50 ml. To optimize the use of this machine, the buffy coat it produces was studied in 12 patients by collecting it in fractions of increasing specific weight. Each fraction was analyzed by morphology, immunocytometry, and cell culture. We found that the buffy coat uniformly contains 8 times more leukocytes than blood, but the proportion of each white cell type varies along a gradient. The lymphocyte-predominant lighter layers are richer in CD34+ cells when compared with the granulocyte-predominant denser layers (6-14 times versus 2-4 times more than blood). The majority of CD34+ cells are found at a light transmission of 10%-70% (hematocrit 6-9). We conclude that cells for transplantation should be collected in a lighter fraction of the buffy coat than originally suggested by the manufacturer.

[Activation of bradykinin formation cascade on receiving autologous blood transfusion through a white cell-reduction filter in a patient treated with an ACE inhibitor]

We have experienced a case of anaphylactoid reaction on receiving autologous blood transfusion through a WBC filter for packed red blood cell (PRBC). The patient was a 71-year-old man with a history of hypertension treated with oral antihypertensive drug; enalapril, an angiotensin converting enzyme (ACE) inhibitor, who received anesthesia for Y-graft replacement. Autologous blood was obtained after the induction of general anesthesia in the operating room. Upon starting to return the stored blood with an unintentional use of a WBC filter, arterial blood pressure (ABP) fell within the first minute of the transfusion. We obtained three blood samples; pre-filtered blood (PRE), postfiltered blood (POST) and arterial blood (CIRC) after the event, and analyzed concentrations of bradykinin (BK), high molecular weight kininogen (HMWK) and high molecular weight kininogen-light chain (HMWK-LC). BK was higher in POST than in PRE. HMWK was lower in POST than in PRE, while HMWK-LC was higher in POST than in PRE. HMWK in CIRC was lower than in PRE, and HMWK-LC was higher in CIRC than in PRE. HMWK and HMWK-LC changes after the event suggest that BK formation cascade in the patient was activated on receiving the transfusion. ACE inhibitors were reported to augment such activation. The WBC filter has the negatively charged surface on filteration material and may activate the cascade. While WBC filters can avoid transfusion related reactions, hemodynamic responses should be watched closely in patients treated with ACE inhibitors.

Safe and efficient peripheral blood stem cell collection in the smallest of children

To clarify the factors that may affect the peripheral blood stem cell (PBSC) collection in children weighing < or = 15 kg, a consecutive registry of 109 leukapheresis procedures was analyzed. Collections were performed on a COBE Spectra separator. In 65.1% of the procedures, the peripheral vein, together with a central catheter inserted routinely at diagnosis, or 2 peripheral veins were used to access/return. For 84.4% of the procedures, the extracorporeal line was primed with red blood cells. The median granulocyte-macrophage colony forming unit (CFU-GM) number derived from 1 patient's blood volume processed was 13.8 x 10(4)/kg. Six times, a collection series failed, always in children treated for > or = 26 weeks and 4 of those times in children weighing < or = 11 kg. The patient's age, diagnosis, duration of preleukapheresis treatment, and mobilization regimens did not significantly affect the collection yield. Twenty-four transplantations were performed. The median times to neutrophils >0.5 x 10(9)/L and platelets >20 x 10(9)/L were 13 and 20 days, respectively. We conclude that even in very small children, leukapheresis can be performed safely, allowing adequate PBSC collection for transplantation and/or in vitro manipulations.

Effect of interface/offset (I/O) adjustment on collection efficiency using the Fenwal CS3000 Plus Blood Cell Separator for peripheral blood progenitor cell collection

Peripheral blood progenitor cells (PBPC) reside within the mononuclear cell (MNC) component of the blood and can be collected using a number of apheresis devices, including the Fenwal CS3000 Plus Blood Cell Separator. Increased MNC collection efficiency, therefore, may reduce the number of apheresis required to achieve collection goals. In this study, patients were divided into groups by absolute MNC count to determine the effect of interface detector offset (I/O) adjustment on MNC collection efficiency. Apheresis products from 104 procedures collected using a standard I/O setting of 100 were compared with 121 collections for which the I/O setting was adjusted according to the preapheresis MNC count. Adjustment of the I/O setting in this manner had no statistically significant impact on the per kilogram dose of MNC collected. The data did show that MNC collection efficiency was reduced as both the MNC count and I/O setting increased, as the collection efficiency was greatest for patients with the lowest peripheral MNC counts and was inversely correlated with the preapheresis MNC count. Although contamination of the product with platelets was drastically reduced at higher I/O settings, there was a concomitant rise in RBC contamination. We conclude that a standard setting of 100 is preferable to adjustment of the I/O setting as a function of the preapheresis MNC count.