Granulocyte collection: a comparison of Fenwal CS 3000, IBM 2997, and haemonetics cell separators

With the advent of sophisticated automated blood processors, the collection of large numbers of granulocytes for transfusion has been made more practical in the past ten years. Harvesting granulocytes by filtration leukapheresis has been abandoned in most centers because of adverse reactions in both donors and recipients. Currently, both continuous and discontinuous flow centrifugation leukapheresis techniques are available. However, both corticosteroids and hydroxyethyl starch are required for optimal granulocyte collection. In this paper, we critically compare the three major cell separators used for the collection of granulocytes by centrifugation leukapheresis. All three instruments separate blood cells by centrifugation; the IBM-2997 and the Fenwal CS-3000 function by continuous-flow centrifugation, and the Haemonetics Model 30 by discontinuous-flow centrifugation. Factors such as the donor preapheresis white blood cell count, the blood flow rate through the machine and the centrifuge speed effect granulocyte collection. Comparisons will be made of the cost of the software for each machine, the time required for granulocyte collection, the convenience of set-up and tear-down, the amount of skill and experience demanded of the operator. Donor factors will be discussed. Since the blood processor may be used for other procedures including plateletpheresis, therapeutic plasma exchange, lymphocytapheresis and erthrocytapheresis, the pros and cons of each machine as used for some of these procedures will be included in the discussion. In our experience, total leukocytes and granulocytes (neutrophils) collected with the three different instruments varied only slightly when unstimulated donors were studied.(ABSTRACT TRUNCATED AT 250 WORDS)

Mononuclear cell collection using various techniques

During the last 15 months, 609 mononuclear cell collections were performed. Lymphocytapheresis and monocytapheresis provides cells for in vitro research studies, investigational transfusion studies and as therapeutic procedures. Automated leukapheresis procedures yields from 1.0-1.5 X 10(9) lymphocytes per liter blood processed. Monocyte yields generally 1/10 of the lymphocyte yields in both lymphocytapheresis and monocytapheresis procedures. Donors had very few reactions, and post collection CBC's showed no significant abnormalities. Mononuclear cell donation appears to have no risk to the normal donor.

The function and structure of granulocytes collected using the IBM 2997 separator

The effect of oral methylprednisolone and the sedimenting agent, hydroxyethyl starch, on granulocyte recovery, morphology, and function was studied in a volunteer donor programme. Using the IBM 2997, 10 litres of whole blood were processed, with an average procedure time of 2.4 hours and a collection volume of 300 ml. Donors not receiving methylprednisolone (n = 80) had a mean total granulocyte count of 3.5 X 10(9)/litre (range 1.6-5.3 X 10(9)/litre) and mean granulocyte yields were 1 X 10(10) (range 0.2-3.0 X 10(10)). Those receiving 48 mg oral methylprednisolone 6-8 hours before the procedure (n = 320) had a mean granulocyte count of 6.3 X 10(9)/litre (range 3.2-11.4 X 10(9)/litre) and significantly superior mean granulocyte yields of 2.0 X 10(10) (0.3-6.5 X 10(10)) (P less than 0.05). For both groups the mean packed cell volume of 0.08 litre/litre (range 0.02-0.17) and platelet contamination 1.9 X 10(11) (range 0.3-5.0 X 10(11)). In all these procedures, hydroxyethyl starch was added to the blood entering the centrifuge channel. In none of the procedures were any untoward symptoms experienced by the donors. Light microscopy and ultrastructural studies showed no difference between control granulocytes and those collected following the addition of hydroxyethyl starch or after oral methylprednisolone. Similarly, granulocyte function measured with a random migration, chemotaxis, phagocytosis, and intracellular killing was not significantly different between control cells and those exposed to the sedimenting agent or the adrenocorticosteroids (P greater than 0.10). It is concluded that donor premedication with methylprednisolone significantly enhances granulocyte yields in the presence of hydroxyethyl starch and neither agent has any demonstrable effect on granulocyte morphology or function.

Comparison of two continuous-flow cell separators

Two blood processors (IBM 2997 and Fenwal CS-3000) were evaluated under similar conditions. Fifty-four leukapheresis procedures with the 2997 resulted in a mean granulocyte yield of 19.4 X 10(9) (42.5% efficiency), with a mean of 2.1 X 10(11) platelets (10.9% efficiency) per product. The CS 3000, at a whole blood flow rate of 50 ml/min, yielded a mean of 13.3 X 10(9) granulocytes (39.2% efficiency) and 4.0 X 10(11) platelets (28.5% efficiency) during 63 leukapheresis procedures. At a flow rate of 60 ml/min, the mean yields of 20 leukapheresis procedures with the CS 3000 were 14.2 X 10(9) granulocytes (30.5% efficiency) and 4.3 X 10(11) platelets (27.8% efficiency). Thirty-four plateletpheresis procedures with the 2997 yielded a mean of 3.62 X 10(11) platelets (53.12% efficiency), and 2.70 X 10(9) white cells. The mean CS-3000 yield for 88 plateletpheresis procedures was 3.15 X 10(11) platelets (49.13% efficiency) with a mean white cell content of 0.67 X 10(9). Granulocyte yields with the 2997 were greater than those obtained with the CS-3000.

Leukapheresis: increasing the granulocyte yield with the Fenwal CS-3000

By premedicating the donor with 60 mg prednisone in divided doses and processing more donor blood at higher flow rates than those specified by the manufacturer, one can obtain high yields of granulocytes and platelets (mean of 3.3 X 10(10) and 5.9 X 10(11), respectively) with the Fenwal CS-3000 blood cell separator. The steroid effect predominates over that of processing more blood. In the case of donors who are not stimulated by steroid, processing 10 L of donor blood at flow rates of 60 to 70 ml/minute results in a significantly improved yield of granulocytes (mean of 2.2 X 10(10) as opposed to 1.4 in the case of 7 L) and of platelets (6.1 X 10(11) versus 4.7). The concentrates contain about 50 to 60% less lymphocytes when donors are given steroid. With these modifications, the leukapheresis can still be accomplished in less than three hours and with minimal adverse effects on the donors.

Use of heparin for cytapheresis and plasmapheresis in a continuous flow centrifuge

We evaluated the use of heparin in continuous flow centrifugation by continuous infusion. Doses were modified by assessment of the anticoagulant effect by the thrombin time dilution test (TTDT). Heparin is an efficient anticoagulant in continuous flow centrifugation and the TTDT is an effective and reliable method for control. The initial dose in leukapheresis is one unit per milliliter of blood during the first hour, then one-half the dose during the next hour, and then a one-quarter of the dose until the procedure is completed. A TTDT performed every 30 to 60 minutes will indicate whether the heparin dose should be modified. For plasmapheresis, it is necessary to determine the specific dose for each patient. There was no case of bleeding or extracorporeal coagulation of the blood.

Response to chronic leukapheresis procedures and survival of chronic myelogenous leukemia patients

Cytoreduction of leukemic leukocytosis by continuous flow centrifugation was used in an intermittent or intensive schedule as primary therapy for an average of sixteen months for management of fifteen patients with chronic myelogenous leukemia. The clinical responses and subsequent survival of the patients was studied. Hematologic and chemical changes related to the procedures and the multiple infusions of the sedimenting agent, hydroxyethyl starch, were also studied. This mode of primary therapy offered no survival advantages to patients. There were no adverse effects of the repeated use of the sedimenting agent observed.

The historical development of automated hemapheresis

Many studies in the early twentieth century involved attempts to separate white blood cells from whole blood for further examination and experimentation as well as for the treatment of neutropenic patients. In the 1950s, the need to use blood and its derivatives efficiently produced the first apparatus to separate blood continuously in a closed system. The prototypes of present-day continuous flow blood cell separators were developed in the 1960s.

Description of a closed plastic bag system for the collection and cryopreservation of leukapheresis-derived blood mononuclear leukocytes and CFUc from human donors

Hemopoietic stem cells were collected from blood by means of continuous-flow centrifugation. The therapeutic use of large quantities of autologous blood stem cells requires a suitable, reliable and easily practicable cryopreservation technique which prevents loss of cell number and viability. This paper describes a closed plastic bag system consisting of one part for the collection and freezing of blood-derived mononuclear cells (MNC), among them granulocyte/macrophage progenitor cells (CFUc), and of a second part for thawing the cryopreserved cells and washing them free of DMSO before transfusion to a patient. In a series of 20 leukaphereses, the average number of collected MNC and CFUc was about 11 x 10(9) and 8 x 10(5) respectively. The recovery rate of the leukapheresis derived MNC and CFUc after cryopreservation, thawing, and washing was demonstrated to be 90 per cent of better. Sequential leukaphereses in the same donor showed little effect on red and white blood cell concentration. However, there was a significant decrease in the donor's blood platelet concentration prior to the third leukapheresis.

[Therapeutic value of the cell separator. Review and case reports]

The advent of continuous-s, semicontinuous-flow centrifugation and filtration leukapheresis systems permits the procurement of large quantities of granulocytes and platelets from single donors and the removal of abnormal excessive blood components (plateletpheresis, lymphapheresis, eosinapheresis, plasma exchange). This paper describes therapeutic applications of CFC, SCFC, FL in various disease processes; the results are discussed. Our data agree with those reported by the litterature.

Leukapheresis and granulocyte transfusion

Granulocyte transfusion is becoming widely used in the treatment of infections in granulocytopenic patients. Several techniques are available for granulocyte collection. Some involve centrifugation of the whole blood and one removes granulocytes from whole blood by reversible adhesion to nylon fibers. The risks to the donor from leukapheresis do not appear to be greater than from whole blood donation. Granulocytes collected by centrifuge techniques function normally in vitro and have normal intravascular recovery and disappearance following transfusion. Granulocytes collected by filtration leukapheresis function almost normally in vitro but have a reduced intravascular recovery and abnormal kinetics as they leave the circulation. The role of leukocyte typing and compatibility testing for granulocyte transfusion is controversial. When the recipient has circulating antibody against donor leukocytes, transfused leukocytes do not circulate or migrate to sites of infection but are sequestered in the liver and spleen. Clinical studies have not defined whether patients benefit equally well clinically from transfusion of compatible or incompatible granulocytes. Initial reports of clinical trials of granulocyte transfusion were promising. However, similar patients who did not receive granulocytes were not studied. Most subsequent controlled trials showed a clear benefit from granulocyte transfusion while others did not. Differences in antibiotic therapy, chemotherapy, use of laminar flow rooms, and grouping of patients make it difficult to compare these clinical trials. Some, but not all, infected granulocytopenic patients benefit from transfusion. Granulocyte transfusions improve survival of granulocytopenic patients with gram negative sepsis and prolonged bone marrow aplasia. Studies are now attempting to identify other patients who should receive granulocytes, the optimum dose and schedule of transfusions, the optimum time to begin transfusion, and the value, if any, of prophylactic transfusions.