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PubMed2002

[Comparison of leucocyte-reduced platelet concentrates produced with spectra version 5.1 and version 7.0 blood cell separators].

In the present study, the performance of a new blood cell separator (COBE Spectra LRS Turbo Version 7.0) and that of the previous version LRS version 5.1 in the collection efficiency (CE), collection rate and residual white blood cells during platelet collection from donors were compared. 232 units of platelet concentrates (n = 232) were evaluated and 163 units were collected with the Spectra LRS version 5.1 (Group A) and 69 units with the LRS turbo version 7.0 (Group B). Donor's blood cell counts and parameters, platelet yield, collection efficiency and residual leukocytes in platelet concentrates were analysed. Results showed that the platelet yield was higher in group B than that in group A: (2.90 +/- 1.1) x 10(11) versus (2.58 +/- 1.2) x 10(11), P < 0.001; residual WBCs were less than 5 x 10(6) in 99.4% of group A platelet concentrates and in 97.1% of group B platelet concentrates. Collection efficiency was higher in group B than in group A: 51.4 +/- 8.7 versus 43.6 +/- 6.3. A correlation between platelet count before collecting blood and platelet yield was observed in both groups. In conclusion, the Spectra LRS Turbo version 7.0 showed a higher platelet yield than that with LRS version 5.1. Higher platelet counts before collection allow a higher platelet yield.

Blood Platelets↗

PubMed2003

An anillin homologue, Mid2p, acts during fission yeast cytokinesis to organize the septin ring and promote cell separation.

Anillin is a conserved protein required for cell division (Field, C.M., and B.M. Alberts. 1995. J. Cell Biol. 131:165-178; Oegema, K., M.S. Savoian, T.J. Mitchison, and C.M. Field. 2000. J. Cell Biol. 150:539-552). One fission yeast homologue of anillin, Mid1p, is necessary for the proper placement of the division site within the cell (Chang, F., A. Woollard, and P. Nurse. 1996. J. Cell Sci. 109(Pt 1):131-142; Sohrmann, M., C. Fankhauser, C. Brodbeck, and V. Simanis. 1996. Genes Dev. 10:2707-2719). Here, we identify and characterize a second fission yeast anillin homologue, Mid2p, which is not orthologous with Mid1p. Mid2p localizes as a single ring in the middle of the cell after anaphase in a septin- and actin-dependent manner and splits into two rings during septation. Mid2p colocalizes with septins, and mid2 Delta cells display disorganized, diffuse septin rings and a cell separation defect similar to septin deletion strains. mid2 gene expression and protein levels fluctuate during the cell cycle in a sep1- and Skp1/Cdc53/F-box (SCF)-dependent manner, respectively, implying that Mid2p activity must be carefully regulated. Overproduction of Mid2p depolarizes cell growth and affects the organization of both the septin and actin cytoskeletons. In the presence of a nondegradable Mid2p fragment, the septin ring is stabilized and cell cycle progression is delayed. These results suggest that Mid2p influences septin ring organization at the site of cell division and its turnover might normally be required to permit septin ring disassembly.

Actins↗

PubMed1988

Adoptive immunotherapy: novel applications of blood cell separators.

Animal models have demonstrated that syngeneic lymphocytes activated ex vivo and infused into animals with experimentally induced tumors can mediate tumor regression. This "adoptive immunotherapy" has been applied to patients with end-stage malignancy refractory to standard therapy. Lymphocytes are collected with the blood cell separator, expanded in culture under the influence of cytokines such as interleukin-2 (IL-2), and reinfused into the patient under conditions similar to those used in the animal models. Studies from several centers using lymphokine-activated killer (LAK) cells, involving more than 300 patients, have shown an overall response rate of greater than 15% and a complete response rate of approximately 10%. Renal cell carcinoma, melanoma, and lymphoma appear to be the cell types that respond best to such therapy. Toxicity in these phase 1 studies has been substantial, related primarily to high doses of intravenous IL-2, and treatment-related deaths have been reported. Adoptive immunotherapy using lymphocytes derived from surgically excised tumors, tumor-infiltrating lymphocytes (TIL), is in the early stages of clinical trials, but this appears to offer a potentially more potent and specific approach than does LAK cell therapy. TIL have been shown to traffic to tumor sites and mediate tumor regression. The mechanisms of adoptive immunotherapy are poorly understood, but blood cell separators and storage technology are playing a critical role in the collection and processing of cells for these research applications.

Blood Component Removal↗

PubMed1981

Estrogen receptor in deciduoma cells separated by velocity sedimentation.

Nuclear estrogen receptor levels were measured in fractions of dispersed deciduoma cells separated according to size by velocity sedimentation at unit gravity. Previous studies demonstrated that velocity sedimentation separated larger fully differentiated polyploid deciduoma cells from smaller diploid cells. Since levels of estrogen receptor measured in homogenates of deciduoma tissue decreased during the growth and differentiation of the deciduoma, lower levels of estrogen receptor per cell were anticipated in polyploid deciduoma cells. Although levels of estrogen receptor decreased slightly in all fractions of deciduoma cells from days 7-8 of pseudopregnancy, the larger polyploid cells had higher levels of estrogen receptor than smaller cells on both days. These results indicate that differentiation of endometrial stromal cells during decidualization involves a decrease in receptor levels in all deciduomal cell types rather than a specific decrease in the receptor levels of only fully differentiated deciduoma cells. (Endocrinology 108: 484, 1981)

Animals↗

PubMed1992

[Therapeutic thrombocytapheresis in patients with myeloproliferative diseases with the cell separators Fresenius AS 104 and Cobe Spectra: biocompatibility and safety].

We studied biocompatibility, safety and efficiency of the two cell separators AS 104 (Fresenius) and Spectra (Cobe) during therapeutic thrombocytaphereses. Although some patients have very high platelet levels and coagulation as well as circulatory equilibrium is easily disturbed, no important activation of coagulation or complement was observed. In respect to patient's safety both cell separators performed very well.

Biocompatible Materials↗

PubMed1995

In-line filtration of platelet concentrates obtained with the Omnix blood cell separator.

The quality of platelet concentrates (PC) obtained with the blood cell separator Omnix was investigated before and after in-line filtration. PC were filtered 2h (protocol A) and 4 h (protocol B) after the termination of apheresis. Platelet (PLT) yield after filtration was similar in both protocols (median 3.7 vs. 3.4 x 10(11)). Median white blood cell (WBC) contamination after leucocyte depletion was 0.07 x 10(6) (range 0.02-3.27 x 10(6)) in protocol A and 0.06 x 10(6) (range 0.02-2.1 x 10(6)) in protocol B. Glucose, lactate, lactate dehydrogenase, morphology score and pH value were not statistically different before and after filtration in both protocols. We conclude that in-line filtration results in sufficient leucocyte depletion of the PC. The prefiltration storage time did not influence the studied parameters of product quality.

Blood Cells↗

PubMedDate not supplied

Use of dextran 150 as a macromolecular agent to improve granulocyte yields on the intermittent flow blood cell separator (Haemonetics Model 30).

Leukaphereses were performed on the intermittent flow cell separator (Haemonentics Model 30) using citrated dextran 150 as a macromolecular agent to improve separation of granulocytes. A mean of 1.77 X 10(10) granulocytes and 7.73 X 10(11) platelets were obtained without steroid stimulation and 2.65 X 10(10) granulocytes and 8.91 X 10(11) platelets were obtained with steroid stimulation of donors. There were no significant adverse reactions to dextran.

Cell Separation↗

PubMed1989

The safety of blood component preparation with blood cell separators.

Despite initial skepticism following the introduction of cytapheresis with blood cell separators, this technology is now accepted in the field of blood donation. Serious, life-threatening reactions have not been observed and thus could not influence the development, and minor problems can be reduced further on the basis of recommended safety guidelines. Additionally, the continuous registration of side effects is helpful for a complete elimination of undesired reactions.

Blood Cells↗

PubMed2000

Bone marrow processing using the fenwal CS-3000 plus blood cell separator: results of 99 procedures.

BMT is used as an established therapy for patients with malignant and nonmalignant diseases. Many techniques for ex vivo treatment have been developed, but these techniques must be preceded by BM processing. We report our experience in processing 99 BM using the Fenwal CS-3000 Plus cell separator using the 1-special program. Ninety-nine procedures were performed in BM harvested from 73 patients and 26 healthy donors. The number of nucleated cells (NC), mononuclear cells (MNC), RBC, platelets, colony-forming units-granulocyte-macrophage (CFU-GM), CD34+ cells, relative purity of MNC and PMN, and volume were determined in the unprocessed BM and in the final product. BM processing resulted in NC, MNC, CFU-GM, and CD34+ cell recoveries of 31%, 82.2%, 117.6%, and 97.8%, respectively. RBC, PMN, platelets, and volume removal, respectively, were 96%, 92%, 37.2%, and 85.1%. In pediatric patients, the volume reduction was significantly lower than in adult patients (79.6% versus 88.8%). No other significant differences were found between pediatric and adult results. We conclude that BM processing with the Fenwal CS-3000 Plus cell separator provides a product that can undergo further ex vivo treatments or cryopreservation.

Adult↗

PubMed2003

Bacteriocidal effects and inhibition of cell separation of cinnamic aldehyde on Bacillus cereus.

AIMS: In this study, bacteriocidal effects of cinnamic aldehyde on Bacillus cereus were investigated. METHODS: The bacterial culture or cell suspension in 0.85% NaCl was treated with cinnamic aldehyde at a concentration of 0.3 ml l(-1). Viable cells were counted on a nutrient agar plate. Protein leakage from the cell was determined using a protein dye. Cell morphology was observed using a scanning electron microscope. RESULTS: Bacillus cereus cells were the most sensitive to cinnamic aldehyde among four different food-borne pathogens. When the cells were treated with 0.3 ml l(-1) of cinnamic aldehyde, the viable counts decreased about 6 log cycles after 6 h of incubation. The bacterial cells remained unlysed although they were killed by cinnamic aldehyde. Treatment of cinnamic aldehyde to the exponential phase cells resulted in no significant protein leakage but strong inhibition of cell separation. CONCLUSIONS: The present findings suggest that cinnamic aldehyde exhibits bacteriocidal effects and inhibition of cell separation on B. cereus. SIGNIFICANCE AND IMPACT OF THE STUDY: These data represent an interesting background for a possible mechanism for antibacterial effects of cinnamic aldehyde.

Acrolein↗

PubMed1981

Distribution and different activation of adenylate cyclase by NaF and of guanylate cyclase by NaN3 in neuronal and glial cells separated from rat cerebral cortex.

Distribution of adenylate cyclase and guanylate cyclase activities in neuronal perikarya and glial cells separated from rat brain, and cellular differences in activation between of adenylate cyclase by NaF and of guanylate cyclase by NaN3 have been studied. Adenylate cyclase activity was higher in the glial cells than in the neuronal fraction, while guanylate cyclase activity was equally detected in both cell fractions. Adenylate cyclase was mainly derived from the particulate fraction of both brain cell homogenates, whereas the major portion of guanylate cyclase activity was found in their soluble rather than in the particulate fractions. Although bulk-separated neurons and glial cells almost failed to change intracellular cyclic nucleotide levels in response to some putative neurotransmitters, activation of adenylate cyclase by NaF was found to be greater in neuronal than in glial cell fractions, and was observed more clearly in the soluble than in the particulate fractions. Sodium azide greatly increased guanylate cyclase in the particulate fraction, but did not affect it considerably in the soluble one. Addition of catalase to the reaction mixture together with NaN3 further stimulated guanylate cyclase both int he soluble and the particulate fractions. These results suggest that adenylate cyclase and guanylate cyclase without intimate coupling to the transmitter-receptor system, but with activation by NaF or NaN3, may be distributed ubiquitously in the cells separated from rat cerebral cortex.

Adenylyl Cyclases↗

PubMed2001

A prospective randomised concurrent comparison of the COBE Spectra Version 4.7, COBE Spectra Version 6 (auto PBSC) and Haemonetics MCS+ cell separators for leucapheresis in patients with haematological and non-haematological malignancies.

A prospective study of the CD34+ cell collection efficiency of three cell separators was undertaken comparing the mononuclear cell, CD34+ cell and CFU-GM yield. Twenty patients were entered in the study, all had received mobilising chemotherapy and daily G-CSF (5 microg/kg subcutaneously). The first leucapheresis was performed when the peripheral blood absolute CD34+ cell count was > or = 20 cells/microl. All patients underwent two leucaphereses on consecutive days. The patients were randomised to undergo either the first or second leucapheresis using the COBE Spectra Version 4.7 and then randomised to either the COBE Spectra Version 6 or Haemonetics MCS+ for the other leucapheresis. The target durations of the procedure on the COBE Spectra Version 4.7 and Version 6 were 180 min or two total blood volumes (TBV), and for the Haemonetics MCS+ was 20 cycles with four recirculations. All machines were operated on the 1997 software supplied by the respective manufacturers. The time taken for the procedure was significantly longer with both the Haemonetics MCS+ and the COBE Spectra Version 6 than the COBE Spectra Version 4.7. Both COBE Spectra versions processed significantly larger volumes of blood than the Haemonetics MCS+. The absolute yield of mononuclear cells, CFU-GM and CD34+ cells were all significantly lower with the Haemonetics MCS+ compared with both COBE Spectra Versions, as were the yields per unit volume of blood processed. There was no significant difference in the reduction in the platelet count following leucapheresis with any of the machines.

Antigens, CD34↗

PubMed1984

Preliminary study on plateletpheresis with the CS-3000 blood cell separator using a single phlebotomy technique.

A coaxial dual flow catheter has been tested for thrombapheresis with a continuous flow blood cell separator in order to render the procedure as comfortable as possible for our donors. Therefore, two groups of five donors underwent a standard plateletpheresis: 3500 ml of blood were withdrawn at a speed of 35-45 ml per minute and were anticoagulated with ACD-A in a 1/9 ratio to whole blood. In the first group one vein puncture was effectuated with the coaxial catheter after local anesthesia. Two 14G catheters were used in the second group. In both groups the platelet yield was studied as well as the half life of 111-Indium-oxinate labeled platelets after autologous transfusion. Although the comfort of the donors was greatly improved, the one needle procedure resulted in a mean platelet yield of 1,28.10 while the two needle procedure yielded 3,46.10 platelets. In contrast, the survival of the platelets after autologous transfusion did not differ significantly in the two groups: t 1/2 in group I was 3,94 d, in group II 3,66 d. It is advocated that the poor efficacy of the single needle procedure might be due to recirculation.

Blood Transfusion, Autologous↗

PubMed1973

Metabolism of Separated Leaf Cells: III. Effects of Calcium and Ammonium on Product Distribution During Photosynthesis with Cotton Cells.

Separated mesophyll cells from cotton (Gossypium hirsutum var. Stoneville 1613 Glandless) were isolated with pectinase and mechanical agitation. The separated cells had rates of light-dependent CO(2) fixation between 50 to 100 mumoles CO(2) per mg chlorophyll per hour. The presence of Ca(2+) in the incubation medium did not significantly affect the type of photosynthetic products formed, but 2 mm Ca(2+) did cause a 50% decrease in the appearance of photosynthetic products in the incubation medium. The movement of all types of products (sugars, organic, and amino acids) out of the cells was reduced similarly by the Ca(2+). Light had no affect on the movement of products out of the cells, whereas 1 mm ethylenediaminetetra-acetate greatly increased the movement. The addition of 1.6 mm NH(4)Cl to the cell suspensions caused a large increase in the amount of fixed (14)C appearing in the amino acid fraction and a decrease in the sugar fraction. These metabolic changes in the cells were reflected in the movement of products out of the cells so that the incubation medium also contained a larger amount of label in amino acids and a smaller amount in sucrose. Although the cell plasma membrane restricted the movement of soluble products, it did not discriminate significantly between the types of products moved.

Journal Article↗

PubMed1980

Citrate induced hypocalcaemia during cell separation.

The value of calcium addition during cell-separation by the Haemonetics Model 30 has been investigated in two patient groups. Where citrated plasma was used as the replacement fluid the addition of calcium abolished clinical symptoms and reduced the degree of citrate induced hypocalcaemia. When Plasma Protein Fraction was used as the replacement fluid, calcium addition was not necessary as clinical symptoms and significant hypocalcaemia did not occur.

Calcium↗

PubMed1991

Comparison of plateletpheresis with two different cell separators using 100 identical donors.

Plateletpheresis with the cell separator COBE Spectra and Fenwal CS 3000 was compared in 100 identical donors. The Spectra was significantly superior with regard to collection efficiency (53% vs. 42%, p less than .001) and leukocyte contamination of the platelet products (.1 x 10(8) vs. 1.4 x 10(8), p less than .001). Additionally, it offers a selectable volume of the concentrate and a better control of the ACD infusion. The Spectra standard procedure needs more ACD, resulting in more citrate dependent donor reactions (5% vs. 1%). In conclusion, the Spectra system shows a more efficient and pure platelet separation compared with the CS 3000.

Adolescent↗

PubMed1999

Biocompatibility of a new cell separator studied by flow cytometry: analyses of platelet antigens during apheresis and storage.

BACKGROUND: Alterations of platelet antigens are known to occur during cytapheresis and storage. These changes have been shown to be dependent on the biomaterials, techniques, and devices used. In this study, the influence of a new cell separator (AMICUS) and storage container (PL-2410) on platelet glycoproteins was analyzed. STUDY DESIGN AND METHODS: During plateletpheresis and storage, the levels of platelet glycoproteins and binding of fibrinogen were determined by flow cytometry. RESULTS: During apheresis, mean channel fluorescence intensity of CD41 a did not change significantly (p = 0.06). A small increase was evident in CD42b mean channel fluorescence intensity, which rose from a baseline level of 178.6 +/- 68.3 to 231.5 +/- 97.9 at the end of the procedure (p<0.05); in CD62p-positive platelets, which increased from 2.0 +/- 0.9 percent to 9.9 +/- 3.9 percent (p<0.05); in CD63-positive platelets, which increased from 1.7 +/- 0.7 percent to 7.9 +/- 2.6 percent (p<0.05); and in the binding of fibrinogen, which increased from 1.9 +/- 0.8 percent positive platelets to 10.5 +/- 2.6 percent (p<0.05). During storage, the mean channel fluorescence intensity of CD41a and CD42b, the percentage of CD62p- and CD63-positive platelets, and the binding of fibrinogen to platelets showed no significant change. CONCLUSION: These studies show that alterations in platelet antigens and platelet activation occur to a small degree during apheresis and storage. These findings demonstrate generally good biocompatibility of this new cell separator.

Adult↗

PubMed1988

[The eccentriplate device on the Dideco Vivacell cell separator for the collection of platelets].

When adapted to the Dideco Vivacell cell separator, the eccentriplate system allows preparation of leukocyte-poor platelet concentrates. Results of its use on 84 procedures showed that a mean of 4.51 x 10(11) platelets were removed in less than 2 hours with a particularly low level of leukocyte contamination: 2.6 x 10(8). Study of platelet function showed them to be altered more by eccentriplate than by conventional removal with the same apparatus. Analysis of recirculation in vivo corroborated the functional anomalies observed with all aggregating agents (with the exception of arachidonate). These anomalies were associated with a quantity of platelets collected at the lower limit of French norms: 30% of the concentrates contained less than 4 x 10(11) platelets. These findings indicate the need for improvement in the eccentriplate system.

Adult↗