Platelet concentrate (PC) remains one of the most important support measures in thrombocytopenic patients. An efficient cell separator is a prerequisite for an optimally functioning apheresis setup. Donor blood count may undergo a temporary reduction after the procedure.
The aim was to find the extent of reduction in donor blood count (hemoglobin, hematocrit, white blood cell, and platelet) after plateletpheresis and to evaluate the cell separator for collection efficiency, processing time, and leukoreduction.
Study Design and Methods:
Two hundred and thirty seven procedures performed on the Amicus (N = 121), Fenwal CS-3000 Plus (N = 50) and Cobe spectra (N = 66) in a one year period were evaluated. The procedures performed on the continuous flow centrifugation (CFC) cell separators and donor blood counts (pre and post donation) done were included in the study.
The percent reduction in hemoglobin (HB), hematocrit (HCT), white blood cell (WBC) and platelet count ((PLT ct) was 2.9, 3.1, 9, 30.7 (Mean, N = 237) respectively after the procedure. The post donation PLT ct reduced to < 100×109/L (range 80-100) in five donors (N = 5/237, Amicus). The pre donation PLT ct in them was 150-200×109/L. Collection efficiency (percent) of Amicus (79.3) was better as compared to the other two machines (CS: 62.5, Cobe: 57.5). PC collected on Cobe spectra had <1×106 WBC. The donor pre donation PLT levels had a positive correlation to the product PLT yield (r = 0.30, P = 0.000).
Monitoring donor blood counts helps to avoid pheresis induced adverse events. A cautious approach is necessary in donors whose pre donation PLT ct is 150-200×109/L. The main variable in PLT yield is donor PLT ct (pre donation). High collection efficiency is a direct measure of an optimally functioning cell separator.
Continuous flow cell separator; donor blood count; plateletpheresis; platelet yield; Blood donor; apheresis
Recruitment of platelets (PLT) during donor PLT apheresis may facilitate the harvest of multiple units within a single donation.
We compared two PLT apheresis procedures (Amicus and Trima Accel) in a prospective, randomized, paired cross-over study in 60 donors. The 120 donations were compared for depletion of circulating PLT in the donors, PLT yields and PLT recruitment. A recruitment was defined as ratio of total PLT yield and donor PLT depletion > 1.
Despite comparable differences of pre- and post-apheresis PLT counts (87 × 109/l in Trima Accel vs. 92 × 109/l in Amicus, p = 0.383), PLT yields were higher with Trima Accel (7.48 × 1011 vs. 6.06 × 1011, p < 0.001), corresponding to a higher PLT recruitment (1.90 vs. 1.42, p < 0.001). We observed a different increase of WBC counts after aphereses, which was more pronounced with Trima Accel than with Amicus (1.30 × 109/l vs. 0.46 × 109/l, p < 0.001).
Both procedures induced PLT recruitment. This was higher in Trima Accel, contributing to a higher yield in spite of a comparable depletion of circulating PLT in the donors. This recruitment facilitates the harvest of multiple units within a single donation and seems to be influenced by the procedure utilized. The different increases of circulating donor white blood cells after donation need further investigation.
Platelet apheresis; Platelet recruitment; Cell separator
Although automated cell separators have undergone a lot of technical refinements, attention has been focused more on the quality of platelet concentrates than on donor safety. We planned this prospective study to observe the effects of automated plateletpheresis on normal haematological values of healthy donors and to determine whether the haematological alterations had any clinical consequences.
Study design and methods
The study was conducted on 457 healthy, first-time plateletpheresis donors over a period of 26 months. The plateletpheresis procedures were performed using five different cell separators and various pre- and post-donation haematological values such as haemoglobin concentration (Hb), haematocrit (Hct), platelet and white blood cell (WBC) counts, mean platelet volume and platelet distribution width were measured in all donors.
We observed that the Hb, Hct, platelet and WBC counts decreased significantly in the donors (p<0.01) after each procedure, without there being significant changes in mean platelet volume or platelet distribution width. The decreases in Hb and Hct were significantly greater with the CS 3000 and Amicus machines, while the decreases in platelet and WBC counts were significantly greater with the CS 3000 and Fresenius separators.
Although a significant drop in complete blood count was observed in all donors, none manifested features of thrombocytopenia or anaemia. Nevertheless, more prospective studies on this aspect are required in order to establish guidelines for donor safety in apheresis and also to help in assessing donor suitability, especially given the present trend of double product apheresis collections.
Plateletpheresis; haematological values; cell separator; donor safety; platelet count
Hemolytic transfusion reactions (HTRs) can occur with transfusion of platelets (PLTs) containing ABO-incompatible plasma. Reported cases have involved group O donors. Two cases of PLT-mediated HTRs associated with the same group A plateletpheresis component, collected from a donor taking high doses of probiotics are reported.
Case 1 was a 40-year-old 69-kg group B stem cell transplant patient who received one-half of a group A plateletpheresis component. Severe back pain occurred 10 minutes into the transfusion, accompanied by anemia and hyperbilirubinemia. Case 2 was a 5-year-old 26-kg group B male with aplastic anemia who received the other half of the same plateletpheresis component, volume reduced to 37 mL. Syncope occurred immediately after the transfusion, with laboratory evidence of hemolysis a few hours later.
Serologic investigation of posttransfusion samples from both patients revealed positive direct anti-globulin tests: C3d only for Case 1 and immunoglobulin (Ig)G and C3d for Case 2; the eluates contained anti-B. The group A donor’s anti-B titer was 16,384 at saline and IgG phases. Donor lookback revealed that the donor had donated 134 apheresis PLTs over many years. For 3 years, he had intermittently taken probiotics; 3 weeks before the index donation, he began taking three tablets of probiotics every day. Lookback of prior group B recipients uncovered a case of acute hemolysis that was not recognized at the time. The solubilized probiotic inhibited anti-B in vitro.
Non–group O PLT donors can have high-titer anti-A or anti-B that might mediate HTRs, and probiotic ingestion in blood donors represents a novel mechanism of stimulating high-titer anti-B.
Blood and apheresis donations are widely considered to be safe with a low incidence of adverse reactions and injuries; however, data reported in the medical literature on the prevalence of adverse events in donors and studies on the predictive risk factors for donor reactions are limited and contradictory.
From January 2002 to December 2006 we recorded every adverse reaction verified during 240,596 consecutive blood and apheresis donations (183,855 homologous whole blood donations, 6,669 autologous whole blood donations, 38,647 plasmapheresis, 2,641 plateletpheresis and 8,784 multicomponent donations) at the Italian Transfusion Centres of Verona and Ragusa,.
Using a special, pre-arranged form within the quality system, a total of 686 adverse reactions (related to 0.28% of all donations) were recorded. Vasovagal reactions, mostly of mild intensity, were the most commonly observed adverse reactions, with a frequency of 0.20% (487/ 240,596). The frequency of the vasovagal reactions varied according to the different types of donation, being 0.19% (346/183,855) for homologous whole blood donations, 0.24% (16/6,669) for autologous whole blood donations, 0.16% (63/38,647) for plasmapheresis, 0.68% (18/2,641) for plateletpheresis and 0.49 (43/8,784) for multicomponent donations. Citrate toxicity was reported in 0.38% (189/50,072) of apheresis donations. Severe adverse reactions were very rare, as they occurred in 0.004% of the donations (10/240,596).
In conclusion, the results of our 5-year survey document that apheresis and blood donation are safe procedures for the donor with a low incidence of adverse reactions; the adverse reactions that did occur were mostly mild and resolved rapidly.
blood donation; apheresis; adverse events
Soluble mediators in platelet concentrates (PCs) released from contaminating white blood cells (WBCs) and platelets (PLTs) themselves are supposed to promote allergic and non-hemolytic febrile transfusion reactions in the recipient. Pathogen reduction technologies (PRTs) prevent replication and proliferation of pathogens as well as of WBCs, and may reduce cytokine accumulation in PCs during storage and prevent adverse events after PLT transfusion. On the other hand, such treatments may also lead to increased cytokine production by stimulation of WBCs or PLTs due to the photochemical or photodynamical process itself.
Material and Methods
12 triple-dose PLT apheresis collections were leukoreduced by the process-controlled leukoreduction system of the Trima Accel machine and split into 3 units undergoing Mirasol-PRT treatment (M) or gamma irradiation (X) or remaining untreated (C). During storage for up to 7 days, PLT activation, WBC-derived Th-1/2, and inflammatory as well as PLT-derived cytokines were measured by cytometric bead array and enzymelinked immunosorbent assay, respectively.
Independent of treatment, all PLT products exhibited low levels of WBC-associated cytokines near or below assay detection limits. WBC-associated cytokines were not elevated by Mirasol-PRT treatment. PLT-derived cytokines were detected at higher levels and increased significantly during storage in all units. Most likely due to higher PLT activation, M units showed significantly higher levels of PLT-derived cytokines compared to untreated and gamma-irradiated units on day 5 of storage.
In all PCs, PLTs themselves were the main source of cytokine release. Mirasol-PRT treatment was associated with a significantly increased PLT activation and accumulation of PLT-derived cytokines during storage, without affecting WBC-derived cytokines relative to controls.
Pathogen reduction; Mirasol-PRT; Ccytokines; Transfusion reaction
We compare the actual with the potential donor exposure and possible infection rates in the Hanover Medical School (MHH) platelet (PLT) transfusion recipients if the current MHH standard of apheresis PLT concentrate (A-PC) supply would be replaced by a pooled PLT concentrate (P-PC) transfusion regimen.
Donors, Patients, and Methods
The electronic records of the MHH Institute of Transfusion Medicine and the MHH Department of Medical Controlling were evaluated to assess the development of PLT needs and supply at MHH from 2003–2006. For 2006, we evaluated all PLT transfusion recipients with respect to their overall transfusion needs, classified them for low and high PLT transfusion needs, and related them to the diagnostic groups that underlie their PLT demands. We assumed a P-PC preparation procedure using 4 whole blood-derived buffy coats for all calculations for potential donor exposure. To predict the possible infection rates of an unrecognized viral infection with low prevalence in the general population to A-PC or to P-PC recipients and the influence of neutralizing agent specific antibodies (NAB), we established a mathematical contamination/infection model based on the current PLT transfusion mode and data about GBV-C virus infection among Hanover blood donors.
From 2003 to 2006, the 1,300–1,400 persons comprising MHH apheresis donor pool covered a 36% increase in PC transfusions. The exclusive use of P-PCs instead of A-PC would require a total of 36,240–49,276 whole blood donations to meet MHH demands, corresponding to a more than 1 log step increase in donor exposure. For individual hematological patients, the change to P-PCs would imply an 80–125%, for individual surgical patients a 40–50% higher donor exposure. Our infection model revealed an approximately 4 times higher infection.
A change to P-PC would imply a more than one log step higher donor exposure, and an unrecognized infection with a prevalence around 1% leads to an up to 4 times higher infection rate. A general change in the PC transfusion policy that favors P-PCs is dangerous and must be avoided.
Donor exposure; Apheresis platelet concentrates; Pooled platelet concentrates; Infection rates from apheresis platelet concentrates; Infection rates from pooled platelet concentrates
Platelet rich plasma-platelet concentrate (PRP-PC), buffy coat poor-platelet concentrate (BC-PC), and apheresis-PC were prepared and their quality parameters were assessed.
In this study, the following platelet products were prepared: from random donor platelets (i) platelet rich plasma - platelet concentrate (PRP-PC), and (ii) buffy coat poor-platelet concentrate (BC-PC) and (iii) single donor platelets (apheresis-PC) by different methods. Their quality was assessed using the following parameters: swirling, volume of the platelet concentrate, platelet count, WBC count and pH.
A total of 146 platelet concentrates (64 of PRP-PC, 62 of BC-PC and 20 of apheresis-PC) were enrolled in this study. The mean volume of PRP-PC, BC-PC and apheresis-PC was 62.30±22.68 ml, 68.81±22.95 ml and 214.05±9.91 ml and ranged from 22-135 ml, 32-133 ml and 200-251 ml respectively. The mean platelet count of PRP-PC, BC-PC and apheresis-PC was 7.6±2.97 × 1010/unit, 7.3±2.98 × 1010/unit and 4.13±1.32 × 1011/unit and ranged from 3.2 –16.2 × 1010/unit, 0.6-16.4 × 1010/unit and 1.22-8.9 × 1011/unit respectively. The mean WBC count in PRP-PC (n = 10), BC-PC (n = 10) and apheresis-PC (n = 6) units was 4.05±0.48 × 107/unit, 2.08±0.39 × 107/unit and 4.8±0.8 × 106/unit and ranged from 3.4 -4.77 × 107/unit, 1.6-2.7 × 107/unit and 3.2 – 5.2 × 106/unit respectively. A total of 26 units were analyzed for pH changes. Out of these units, 10 each were PRP-PC and BC-PC and 6 units were apheresis-PC. Their mean pH was 6.7±0.26 (mean±SD) and ranged from 6.5 – 7.0 and no difference was observed among all three types of platelet concentrate.
PRP-PC and BC-PC units were comparable in terms of swirling, platelet count per unit and pH. As expected, we found WBC contamination to be less in BC-PC than PRP-PC units. Variation in volume was more in BC-PC than PRP-PC units and this suggests that further standardization is required for preparation of BC-PC. As compared to the above two platelet concentrates, all the units of apheresis-PC fulfilled the desired quality control criteria of volume. Apheresis-PC units showed better swirling and platelet count than PRP-PCs and BC-PCs. All the platelet concentrates units had pH well above the recommended norm.
Corrected count increment; buffy coat poor-platelet concentrate; percentage recovery; platelet concentrate; platelet rich plasma-platelet concentrate; random donor platelet; single donor platelets
Cell separators in India are routinely used for plateletpheresis, peripheral blood stem cell collections and therapeutic plasma exchange. Therapeutic leukapheresis, particularly as an emergency procedure, has been uncommonly performed and reported. Here, a case of a 53-year-old male, diagnosed with acute myeloid leukemia subtype M5 (AML M5) with hyperleukocytosis, who underwent emergency leukaphereis, is reported. After two procedures, there was a decrease of WBC count by 85%, which enabled cytotoxic therapy to be initiated.
Emergency; hyperleukocytosis; leukapheresis
The combination of granulocyte–colony-stimulating factor (G-CSF [filgrastim]) and dexamethasone (G-CSF/dex) is an effective granulocyte mobilization regimen, but the variables that affect donor neutrophil response and granulocyte collection yield are not well characterized.
STUDY DESIGN AND METHODS
A computerized database containing records of 1198 granulocyte collections from 137 unrelated volunteer apheresis donors during a 13-year period was retrospectively analyzed. Donors were categorized by age, sex, and cumulative number of granulocyte donations. Complete blood counts at baseline and after G-CSF/dex stimulation were recorded. The outcome variables include the pre-procedure absolute neutrophil count (preANC), which reflects G-CSF/dex stimulation, and the granulocyte product yield per liter processed (BagGranYield/L).
Higher baseline ANC and platelet (PLT) counts were significantly associated with higher preANC while a larger number of prior granulocytapheresis procedures was associated with lower preANC. Total filgrastim dose (used in weight-based dosing) did not significantly impact preANC or the granulocyte yield; weight-based dosing at 5 μg per kg and a uniform 480-μg dose produced equivalent preANC. PreANC and weight were the key determinants of granulocyte yield (BagGranYield/L).
Apheresis donors with higher baseline PLT counts and ANCs have higher ANCs after G-CSF/dex stimulation; donor age, weight, and sex do not have a significant impact. A uniform G-CSF dose of 480 μg is as effective as weight-based dosing at 5 μg per kg. Donor ANC monitoring should be considered after serial granulocytapheresis procedures.
In vitro function of stored platelet (PLT) con-centrates was analyzed after applying two different techniques of pathogen reduction technology (PRT) treatment, which could increase cellular injury during processing and storage.
Nine triple-dose PLT apheresis donations were split into 27 single units designated to riboflavin-UVB (M) or psoralen-UVA (I) treatment or remained untreated (C). Throughout 8 days of storage, samples were analyzed for annexin V release, the mitochondrial transmembrane potential (Δψ) and some classical markers of PLT quality (pH, LDH release, hypotonic shock response (HSR)).
PLT count and LDH release of all units maintained initial ranges. All units exhibited a decrease in pH and HSR and an increase in annexin V release and Δψ disruption. Notably, throughout the entire storage period, annexin V release re-mained lowest in M units. Throughout 7 days of storage, M units remained comparable to C units (p > 0.05), whereas inferior values were observed with I units. Here, differences to C units reached significance by day 1 (pH: p < 0.0001), day 5 (annexin V release: p < 0.014), and day 7 (HSR, Δψ: p ≤ 0.003). After PRT treatment, annexin V release and Δψ disruption were significantly (p < 0.001) correlated with pH and HSR.
During storage, all units showed a de-crease in HSR and an increase in acidity, annexin V release and Δψ disruption. While M units remained comparable to C units, I units demonstrated significantly inferior values during terminal storage. This could have resulted from differences in PRT treatment or simply be due to differences in storage media and should be analyzed for clinical relevance in future investigations.
Pathogen reduction technology; Platelet in vitro function; Endogenous annexin V; Transmembrane mitochondrial potential; INTERCEPT BLOOD SYSTEM; MIRASOL-PRT
Apheresis donors are routinely evaluated with a complete blood count (CBC). Low red blood cell mean corpuscular volume (MCV) values (<80 fL) in the presence of an acceptable hemoglobin (Hb; ≥12.5 g/dL) could be due to iron deficiency or hemoglobinopathy. The etiology of a low MCV in a healthy apheresis donor population was assessed.
Predonation samples for CBC were obtained from 1162 consecutive apheresis donors. Donors with a MCV of less than 80 fL were evaluated by CBC, iron studies (ferritin, serum iron, transferrin, percentage of transferrin saturation), and hemoglobin (Hb) electrophoresis. Iron deficiency was defined as a ferritin value below the reference range. Beta chain Hb variants were determined by Hb electrophoresis. Alpha thalassemia trait was presumed if the red blood cell (RBC) count was elevated, no variant Hbs were detected, and the iron studies were within normal ranges.
In a 19-month period, 33 of 1162 apheresis donors had low MCV values. Iron deficiency was present in 64%; 49% had isolated iron deficiency and 15% had iron deficiency plus hemoglobinopathy. Hemoglobinopathy without concomitant iron deficiency was found in the remaining 36%.
Iron deficiency is present in the majority of apheresis donors with repeatedly low MCV values and Hb levels of 12.5 g/dL or more. Hemoglobinopathy is also commonly present but may not be easily recognized in the setting of iron deficiency. The MCV is a useful screening tool to detect iron deficiency and hemoglobinopathy. Low MCV values should be investigated to determine if iron replacement therapy is indicated.
Transfusion-associated bacterial infections are a quite frequent collateral effect of administration of platelet concentrates (PC). We carried out a microbiological surveillance of bacterial contamination of apheresis platelet concentrates by studying microbial flora on donors’ arms before and after skin disinfection, through blood cultures with the diversion volume and with the PC.
Materials and methods
Platelet aphereses were carried out using two Haemonetics MCS+ instruments. Cutaneous swabs were examined by the direct plate technique and blood cultures were performed using Bact/ALERT aerobic bottles. In the 5 years from January 2001 to December 2005 we tested 481 PC.
Cutaneous swabs showed significant bacterial growth in 89% of cases before skin disinfection and in 44% after. None of the blood cultures performed on diversion blood was positive, one (0.2%) PC was positive on the fifth day after collection and the presence of a Staphylococcus epidermidis strain was demonstrated.
Our results suggest that the skin disinfection protocol adopted in our structure is not fully satisfactory. The cultures performed on the PC showed a low prevalence of contamination, and the only positive sample was contaminated by a common skin contaminant (S. epidermidis). The culture became positive on the fifth day after collection, but on the second day the PC had been transfused to a patient, without any adverse reaction.
In our experience a culture method using Bact/ALERT aerobic bottles was not able to prevent transfusion of the only contaminated PC identified in this study.
apheresis; platelet concentrates; microbiological contamination; arm disinfection
Since 1999, in Mexico we have been using a regimen to conduct allografts that involves non-myeloablative conditioning and peripheral blood stem cells (PBSC) and have introduced some changes with the main goal of decreasing the cost of the procedure.
Materials and methods
We analysed the salient apheresis features of a group of 175 allogeneic peripheral blood stem cell transplants conducted in two institutions in a 7-year period. The grafts were conducted using the “Mexican” non-myelo ablative conditioning regimen employing oral busulphan, i.v. cyclophosphamide and i.v. fludarabine. In all instances, the apheresis machine employed was the Baxter CS3000 Plus and donors were mobilised with filgrastim. The apheresis procedures were performed on days 0, +1 and +2, the end-point of collection being 5,000 mL of blood/m2 in each procedure. Three apheresis sessions were planned but the number was adjusted according to the cell yield.
The final number of allografted CD34 cells ranged between 0.5 and 25.4 × 106/Kg of the recipient’s body weight (median, 5.2 × 106/Kg). One to three apheresis procedures were needed to obtain a product containing more than 0.5 × 106 CD34 cells/Kg of the recipient, the median being two procedures; in 72 cases (41%) a single apheresis procedure was sufficient to obtain the target number of CD34 cells. The volumes of apheresis ranged between 50 and 600 mL (median, 400 mL).
Since the median cost of each apheresis procedure is 900 USD, the fact that two apheresis procedures was spared in 72 cases and one apheresis was spared in another 65 cases, led to a total saving of approximately 188,100 USD. It can be concluded that, in many cases, allogeneic transplants can be completed with a single apheresis session and that there are considerable financial benefits from this practice.
apheresis; allografts; costs saving; transplantation
In microcirculation disorders, the therapeutic apheresis seems to have two different effects. The first, achieved after only a few sessions, is acute, consisting of drastic reduction of blood viscosity and obtained with the use of low-density lipoprotein (LDL) apheresis, rheopheresis, or fibrinogen apheresis. The second effect is long term, or chronic, and needs to be evaluated after a long course of treatment. The mechanisms underlying the chronic effect are still objects of debate and take into account the pleiotropic effects of apheresis. However, it is likely that the acute effect of apheresis mainly influences the functional components of the vascular damage, and so the derived rheological benefit might last only for a short period. The chronic effect, on the contrary, by acting on the morphological alterations of the vascular walls, requires the apheresis treatment to be prolonged for a longer period or even cycles of treatment to be programmed.
LDL apheresis; Rheopheresis; Microcirculation disorders; Peripheral arterial disease
In high-volume processing environments, manual breakage of in-line closures can result in repetitive strain injury (RSI). Furthermore, these closures may be incorrectly opened causing shear-induced hemolysis. To overcome the variability of in-line closure use and minimize RSI, Fresenius Kabi developed a new in-line closure, the CompoFlow, with mechanical openers.
STUDY DESIGN AND METHODS
The consistency of the performance of the CompoFlow closure device was assessed, as was its effect on component quality. A total of 188 RBC units using CompoFlow blood bag systems and 43 using the standard bag systems were produced using the buffy coat manufacturing method. Twenty-six CompoFlow platelet (PLT) concentrates and 10 control concentrates were prepared from pools of four buffy coats. RBCs were assessed on Days 1, 21, and 42 for cellular variables and hemolysis. PLTs were assessed on Days 1, 3, and 7 for morphology, CD62P expression, glucose, lactate, and pH. A total of 308 closures were excised after processing and the apertures were measured using digital image analysis.
The use of the CompoFlow device significantly improved the mean extraction time with 0.46 ± 0.11 sec/mL for the CompoFlow units and 0.52 ± 0.13 sec/mL for the control units. The CompoFlow closures showed a highly reproducible aperture after opening (coefficient of variation, 15%) and the device always remained opened. PLT and RBC products showed acceptable storage variables with no differences between CompoFlow and control.
The CompoFlow closure devices improved the level of process control and processing time of blood component production with no negative effects on product quality.
Recently in Northern Ireland there has been a rapid increase in demand for a variety of blood components. To meet this need a large proportion of routine blood donations must be processed at the Transfusion Centre. In addition, several blood components are collected direct from donors by apheresis techniques. Apheresis is currently restricted to the collection of components from highly selected donors, but in future this method is likely to be employed for collection of some routine components. This changing pattern is placing increasing demands on many of our blood donors.
Transfusion of granulocytapheresis concentrates can be limited by the volume of incompatible donor red blood cells (RBCs) in the component. Efficient reduction of RBCs in granulocyte units would result in safe transfusion of RBC-incompatible units.
STUDY DESIGN AND METHODS
Granulocyte concentrates were collected by continuous-flow apheresis from granulocyte–colony-stimulating factor (G-CSF) and dexamethasone-stimulated volunteer donors, with 6% hydroxyethyl starch (HES) added continuously during apheresis as a RBC sedimenting agent to enhance granulocyte collection efficiency. After collection, the component was placed in a plasma extractor for 4 hours. A sharp line of demarcation between the starch-sedimented RBCs and the granulocyte-rich supernatant developed, and the supernatant was transferred to a sterilely docked transfer pack. RBC reduction and white blood cell recovery were determined.
Gravity sedimentation was performed on 165 granulocyte concentrates. Mean sedimentation time was 267 minutes (range, 150–440 min). RBC depletion was 92% (range, 71%–99%) with mean residual RBC content of 3.2 ± 1.4 mL. Twelve percent of components contained less than 2 mL of RBCs. Mean granulocyte and platelet (PLT) recoveries were 80 and 81%, respectively. There were no transfusion reactions or signs of hemolysis after transfusion of 66 RBC-incompatible granulocyte concentrates (RBC volume, 1.6–8.2 mL). The remaining concentrates were used for topical or intrapleural applications.
RBCs were significantly reduced and granulocytes and PLTs effectively retained in G-CSF/ steroid–mobilized granulocyte components collected with HES and processed by gravity sedimentation. This procedure allows safe transfusion of RBC-incompatible sedimented granulocyte units and may be used to expand the pool of available granulocyte donors for specific recipients.
This study investigated the effect of blood donation environment, fixed or mobile with differing sponsor types, on donation return time.
STUDY DESIGN AND METHODS
Data from 2006 through 2009 at six US blood centers participating in the Retrovirus Epidemiology Donor Study-II (REDS-II) were used for analysis. Descriptive statistics stratified by whole blood (WB), plateletpheresis (PP), and double red blood cell (R2) donations were obtained for fixed and mobile locations, including median number of donations and median interdonation interval. A survival analysis estimated median return time at fixed and mobile sites, while controlling for censored return times, demographics, blood center, and mandatory recovery times.
Two-thirds (67.9%) of WB donations were made at mobile sites, 97.4% of PP donations were made at fixed sites, and R2 donations were equally distributed between fixed and mobile locations. For donations at fixed sites only or alternating between fixed and mobile sites, the highest median numbers of donations were nine and eight, respectively, and the shortest model-adjusted median return times (controlling for mandatory eligibility times of 56 and 112 days) were 36 and 30 days for WB and R2 donations, respectively. For PP donations, the shortest model-adjusted median return time was 23 days at a fixed location and the longest was 693 days at community locations.
WB, PP, and R2 donors with the shortest time between donations were associated with fixed locations and those alternating between fixed and mobile locations, even after controlling for differing mandatory recovery times for the different blood donation procedures.
The aim of this study was to evaluate the influence of an infusion of NaCl 0.9% 500 ml during preparatory plasmapheresis or apheresis on the immunoglobulin G (IgG) content in separated plasma.
32 donors of plasma were studied in a crossover design after informed consent on one day without NaCl 0.9% 500 ml during apheresis and on another day with infusion of NaCl 0.9% 500 ml during apheresis. Infusion of NaCl 0.9% 500 ml was given step by step in divided doses after each cycle through the harness set of the Haemonetics® plasma collecting system 2 (PCS2). Concentrations of IgG in serum and in plasma were measured by an immunoturbidimetric assay. Percentages of IgG concentrations in plasma were calculated by dividing the IgG concentration in plasma by the mean serum IgG concentrations (x 100).
Without infusion of NaCl 0.9% 500 ml, the mean percentage of IgG in separated plasma was 85.5 ± 2.3% while it was 80.5 ± 3.4% when NaCl 0.9% 500 ml was given. The difference between the two samples was statistically highly significant (p < 0.001).
We conclude that the gradual infusion of NaCl 0.9% 500 ml during apheresis causes a statistically highly significant difference of IgG content in separated plasma.
Apheresis; Immunoglobulin G; NaCl 0.9% infusion; Plasmapheresis
The administration of granulocyte colony-stimulating factor (G-CSF) to peripheral blood progenitor cell (PBPC) donors causes spleen length to increase, but the duration of enlargement is not known. Eighteen healthy subjects were given 10 μg/kg of G-CSF for 5 days and a PBSC concentrate was collected by apheresis. Ultrasound scans were used to assess craniocaudal spleen length before and after G-CSF administration. Mean spleen length increased from a baseline length of 10.7 ± 1.3 cm to 12.1 ± 1.2 cm on the apheresis day (p < 0.001). Ten days after apheresis, spleen length fell to 10.5 ± 1.2 cm and did not differ from baseline levels (p = 0.57), but in 3 subjects remained 0.5 cm greater than baseline length. Increases in spleen length in PBPC donors are transient and reversible.
granulocyte colony-stimulating factor; peripheral blood progenitor cells; splenomegaly; spleen
Platelet Rich Plasma-Platelet concentrate (PRP-PC), Buffy Coat poor-platelet concentrate (BCPC), and Apheresis — PC were prepared and their therapeutic efficacy were assessed in thrombocytopenic patients.
Study design and methods
PRP-PC and BC-PC were prepared from whole blood and Apheresis-PC by automated cell separator. The post transfusion efficacy of transfused platelets was assessed at 1 hour and 20 hours by corrected count increment (CCI) and percentage recovery (PR).
A total of 60 patients’ (20 each for PRP-PC, BC-PC and Apheresis-PC) were enrolled in this study. Forty one patients received therapeutic and nineteen received prophylactic transfusion support. Patients with aplastic anemia 43% (25/60) and acute leukemia 38% (23/60) formed a majority of study population. Platelet dosage of patients’ received PRP-PC, BC-PC and apheresis-PC were 2.4±0.82 × 1011 (mean±SD), 2.2±0.83 × 1011 (mean±SD) and 4.14±1.82 × 1011 (mean±SD) and ranged from 1.16–4.11 × 1011, 1.04−4.20 × 1011 and 1.22−8.90 × 1011 respectively. There was significantly increase in inter-transfusion interval with Apheresis-PC than with PRP-PC and BC-PC recipients [(Mean±S.D.), 4.7±1.33 days Vs 2.7±0.82 days Vs 2.5±0.7 days respectively] (p < 0.05).
Patients transfused with apheresis-PC had received higher platelet dosage than PRP-PC and BC-PC and this difference was statistically significant (p < 0.001). The post transfusion platelet counts and increments at 1 hour and 20 hours were significantly higher with apheresis-PC than PRP-PC and BC-PC (p < 0.001). However, the corrected count increment (CCI) and percentage recovery (PR) in all three groups were comparable. There was significantly increase in inter-transfusion interval with apheresis-PC than PRPPC and BC-PC (p < 0.05).
Random donor platelets; Buffy coat poor-platelet concentrate; Platelet Rich Plasma-Platelet concentrate; Thrombocytopenic patients
In Saccharomyces cerevisiae, the transcription factors Tec1p and Ste12p are required for haploid invasive and diploid pseudohyphal growth. Tec1p and Ste12p have been postulated to regulate these developmental processes primarily by cooperative binding to filamentous and invasion-responsive elements (FREs), which are combined enhancer elements that consist of a Tec1p-binding site (TCS) and an Ste12p-binding site (PRE). They are present in the promoter regions of target genes, e.g., FLO11. Here, we show that Tec1p efficiently activates target gene expression and cellular development in the absence of Ste12p. We further demonstrate that TCS elements alone are sufficient to mediate Tec1p-driven gene expression by a mechanism termed TCS control that is operative even when Ste12p is absent. Mutational analysis of TEC1 revealed that TCS control, FLO11 expression, and haploid invasive growth require the C terminus of Tec1p. In contrast, the Ste12p-dependent FRE control mechanism is sufficiently executed by the N-terminal portion of Tec1p, which contains the TEA/ATTS DNA-binding domain. Our study suggests that regulation of haploid invasive and diploid pseudohyphal growth by Ste12p and Tec1p is not only executed by combinatorial control but involves additional control mechanisms in which Ste12p activates TEC1 expression via clustered PREs and where Tec1p regulates expression of target genes, e.g., FLO11, by TCS control.
Thymocytes differentiate in the thymic microenvironment into immunocompetent T cell through the interaction with a variety of accessory cells, including thymic epithelial cells (TEC). TEC plays an important role in the selection process presenting self antigens in association with major histocompatibility complex (MHC) molecules to the maturing T cells. The T cell receptor recognizes the self antigen- MHC complex, but other surface molecules help stabilize this interaction. Thus, the CD2/LFA-3 and LFA-1/intercellular adhesion molecule 1 pairs have been shown to participate in the binding between lymphoid cells and TEC. Here we describe an integrin of the very late activation antigen subfamily composed by the known beta 1 chain and by a novel alpha chain. This adhesion molecule is expressed on the surface of medullary TEC and is involved in the adhesion between TEC and thymocytes, but not peripheral blood T lymphocytes.
To evaluate the effectiveness and safety of the mobilization of peripheral blood hematopoietic stem cells by combining docetaxel with granulocyte colony-stimulating factor (G-CSF) in breast cancer patients.
A total of 57 breast cancer patients were treated with docetaxel 120 mg/m2. When the white blood cell (WBC) count decreased to 1.0×109/L, patients were given G-CSF 5 μg/kg daily by subcutaneous injection until the end of apheresis. Peripheral blood mononuclear cells (MNC) were isolated by Cobe Spectra Apheresis System. The percentage of CD34+ cell was assayed by flow cytometry.
At a median 6 of days (range 3-8) after the administration of docetaxel, the median WBC count decreased to 1.08×109/L (range 0.20-2.31). The median duration of G-CSF mobilization was 3 days (range 2-7). The MNC collection was conducted 8-12 days (median 10 days) after docetaxel treatment. The median MNC was 5.35×108/kg (range 0.59-14.07), the median CD34+ cell count was 2.43×106/kg (range 0.16-16.69). The CD34+ cell count was higher than 1.00×106/kg in 47 of 57 cases (82.46%) and higher than 2.00×106/kg in 36 cases (63.16%). The CD34+ cell count was higher than 2.00×106/kg in 27 collections (23.68%). The MNC count and the CD34+ cell count were correlated with the bottom of WBC after docetaxel chemotherapy (r=0.364, 0.502, P=0.005, 0.000). The CD34+ cell count was correlated with the MNC count (r=0.597, P=0.000). The mobilization and apheresis were well tolerated in all patients. Mild perioral numbness and numbness of hand or feet were observed in 3 cases. No serious adverse events were reported.
Mobilization of peripheral blood hematopoietic stem cell by combining docetaxel with G-CSF was effective and safety in breast cancer patients.
Docetaxel; Granulocyte colony-stimulating factor (G-CSF); Mobilization; Stem cell