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BACKGROUND: Short- and long-term effects of mobilization regimens in hematopoietic stem cell and granulocyte donors have been well characterized. In this study, we examined the longitudinal hematopoietic changes related to repeat stimulated granulocyte donation. STUDY DESIGN AND METHODS: Complete blood counts for consecutive granulocyte donors between October 1994 and May 2017 were compared to unstimulated granulocyte donors. Plateletpheresis donors served as controls. The longitudinal change in precollection white blood cell (WBC) counts for these donor groups were modeled using a linear mixed-effects model. The investigated variables were granulocyte, lymphocyte, and monocyte counts and the granulocyte collection yield. Contrasts were performed to explore the effect of donation number on precollection counts. RESULTS: For the granulocyte-colony-stimulating factor plus dexamethasone (G-CSF/Dex)-stimulated group, both the granulocyte and the lymphocyte counts decreased 6.51 × 10(9)/L (−23.1%, p < 0.001) and 0.21 × 10(9)/L (−20.4%, p < 0.001), respectively, between Donation 1 and Donation 20. This effect was still present at the 3- to 4-year interval (b = −0.0008313, SE = 0.00029, p = 0.004). For the unstimulated donor group between Donation 1 and Donation 20, the lymphocyte count decreased by 0.62 × 10(9)/L (−51.5%, p < 0.001). This effect was only significant up to Year 2 (b = −0.0026, SE = 0.0010, p = 0.013). CONCLUSIONS: Past granulocyte donations were found to have a statistically strong negative effect on precollection granulocyte counts and lymphocyte counts and decreased granulocyte yield both in the G-CSF/Dex—stimulated donors and the unstimulated donors. In this statistical model, for both these groups, the effect of past donations on granulocyte and WBC counts were still detectable 2 years later.

BACKGROUND Thrombocytosis (or, less commonly, thrombocytopenia) is associated with iron-deficiency anemia and resolves with iron therapy. Many volunteer blood donors have low iron stores, with or without anemia. Iron balance could affect platelet counts in blood donors. STUDY DESIGN AND METHODS Whole blood donors deferred for finger-stick hemoglobin levels less than 12.5 g/dL were evaluated by complete blood count and serum iron panel before and after oral iron treatment. Group assignment for iron depletion was based on serum ferritin cutoffs of less than 20 µg/L for women and less than 30 µg/L for men or was based on changes in serum ferritin levels after iron replacement. RESULTS Among 1273 Hb-deferred whole blood donors, 55% (619 of 1128) of the women and 70% (102 of 145) of the men were iron depleted. Iron-depleted donors had higher platelet counts compared with donors who had normal ferritin levels (women: 286 vs. 268 × 103/µL; p 400 × 103/µL) compared with 2.0% of donors who had normal ferritin levels (p = 0.017). Iron replacement decreased platelet counts in iron-depleted female donors (mean, −19,800/µL; interquartile range, 8000 to −45,000/μL), but not in donors who had normal or stable ferritin levels. The same trends were observed in male donors. CONCLUSION Iron-depleted donors had higher platelet counts than donors who had adequate iron stores. Oral iron replacement decreased platelet counts on average by about 20,000/µL in iron-depleted donors but had no effect on platelet counts in donors who had normal or stable ferritin levels.

BACKGROUND Granulocyte-colony-stimulating factor (G-CSF)-stimulated hematopoietic progenitor cells (HPCs) collected by apheresis have become the predominant graft source for HPC transplantation in adults. Among healthy allogeneic donors, demographic characteristics (age, sex, body mass index [BMI]) and baseline hematologic counts affect HPC mobilization, leading to variability in CD34+ apheresis yields. Racial differences in HPC mobilization are less well characterized. STUDY DESIGN AND METHODS We retrospectively analyzed data from 1096 consecutive G-CSF-stimulated leukapheresis procedures in healthy allogeneic African American (AA) or Caucasian donors. RESULTS In a multivariate analysis, after adjusting for age, sex, BMI, baseline platelet and mononuclear cell counts, and daily G-CSF dose, peak CD34+ cell mobilization was significantly higher among AAs (n = 215) than Caucasians (n = 881; 123 ± 87 × 10(6) cells/L vs. 75 ± 47 × 10(6) cells/L; p

Background Therapeutic phlebotomy is increasingly used in patients with transfusional siderosis to mitigate organ injury associated with iron overload (IO). Laboratory response parameters and therapy duration are not well characterized in such patients.

Background Granulocyte–colony-stimulating factor (G-CSF)-mobilized autologous hematopoietic progenitor cells (HPCs) may be collected by apheresis of patients with chronic granulomatous disease (CGD) and severe combined immunodeficiency (SCID) for use in gene therapy trials. CD34+ cell mobilization has not been well characterized in such patients. Study Design and Methods We retrospectively evaluated CD34+ cell mobilization and collection in 73 consecutive CGD and SCID patients and in 99 age-, weight-, and G-CSF dose–matched healthy allogeneic controls. Results In subjects aged not more than 20 years, Day 5 preapheresis circulating CD34+ counts were significantly lower in CGD and SCID patients than in controls; mean peak CD34+ cell counts were 58 × 106, 64 × 106, and 87 × 106/L, respectively (p = 0.01). The SCIDs had lower CD34+ collection efficiency than CGDs and controls; mean efficiencies were 40, 63, and 57%, respectively (p = 0.003). In subjects aged more than 20 years, the CGDs had significantly lower CD34+ cell mobilization than controls; mean peak CD34+ cell counts were 41 × 106 and 113 × 106/L, respectively (p

Background Pica and restless legs syndrome (RLS) are associated with iron depletion and deficiency. The presence of pica and RLS was prospectively assessed in blood donors. Study Design and Methods During a 39-month period, 1236 donors deferred for fingerstick hemoglobin (Hb) level of less than 12.5 g/dL and 400 nondeferred “control” donors underwent health screening and laboratory testing (complete blood count, ferritin, iron, transferrin). Pica and RLS were assessed by direct questioning. Deferred donors and iron-deficient control donors were given 325 mg of ferrous sulfate daily for 60 days. Reassessments were performed and additional iron tablets dispensed at subsequent visits. Results Pica was reported in 11% of donors with iron depletion or deficiency, compared with 4% of iron-replete donors (p

BACKGROUND: Iron depletion or deficiency in blood donors frequently results in deferrals for low hemoglobin (Hb), yet blood centers remain reluctant to dispense iron replacement therapy to donors. STUDY DESIGN AND METHODS: During a 39-month period, 1236 blood donors deferred for a Hb level of less than 12.5 g/dL and 400 nondeferred control donors underwent health history screening and laboratory testing (complete blood counts, iron studies). Iron depletion and deficiency were defined as a ferritin level of 9 to 19 and less than 9 µg/L in females and 18 to 29 and less than 18 µg/L in males. Deferred donors and iron-deficient control donors were given a 60-pack of 325-mg ferrous sulfate tablets and instructed to take one tablet daily. Another 60-pack was dispensed at all subsequent visits. RESULTS: In the low-Hb group, 30 and 23% of females and 8 and 53% of males had iron depletion or deficiency, respectively, compared with 29 and 10% of females and 18 and 21% of males in the control group. Iron-depleted or -deficient donors taking iron showed normalization of iron-related laboratory parameters, even as they continued to donate. Compliance with oral iron was 68%. Adverse gastrointestinal effects occurred in 21% of donors. The study identified 13 donors with serious medical conditions, including eight with gastrointestinal bleeding. No donors had malignancies or hemochromatosis. CONCLUSION: Iron depletion or deficiency was found in 53% of female and 61% of male low-Hb donors and in 39% of female and male control donors. Routine administration of iron replacement therapy is safe and effective and prevents the development of iron depletion and deficiency in blood donors.

We have previously reported that left ventricular (LV) diastolic function in those with cardiac asymptomatic hereditary hemochromatosis (HH) is similar to that of volunteer control (VC) subjects, despite a presence of augmented left atrial contractile function. However, concern still exists that those with HH might gradually develop LV diastolic dysfunction despite receiving conventional phlebotomy treatment. To address this concern, we prospectively monitored the LV diastolic function of those with HH and VCs during a 5-year period. A total of 14 subjects with newly diagnosed HH (age 51 ± 12 years, 4 women, group A), 20 with chronic HH (age 51 ± 9 years, 7 women, group B), and 18 VCs (age 50 ± 8 years, 6 women, group C) successfully completed both the baseline evaluation of LV diastolic function, including tissue Doppler imaging, strain rate analysis with color-coded tissue Doppler, and the same studies repeated at 5 years of follow-up. All those with HH were New York Heart Association functional class I, were positive for the C282Y homozygote, and received conventional phlebotomy therapy. No VC had HH genetic mutations. The measures of LV diastolic function were comparable among the groups at 5 years of follow-up by analysis of variance. The echocardiographic measures of active left atrial contraction tended to decrease in the HH groups at 5 years of follow-up from baseline. In conclusion, LV diastolic function does not significantly deteriorate statistically during a 5-year period in subjects with cardiac asymptomatic HH after conventional phlebotomy treatment, regardless of their treatment history.

Background—Reports of monosomy 7 in patients receiving granulocyte colony stimulating factor (G-CSF) have raised concerns that this cytokine may promote genomic instability. However, there are no studies addressing whether repeated administration of G-CSF produces monosomy 7 aneuploidy in healthy donors. Study Design and Methods—We examined chromosomes 7 and 8 by fluorescent in situ hybridization (FISH) in CD34+ cells from 35 healthy hematopoietic stem cell transplant (HSCT) donors after G-CSF administration for 5 days, and by spectral karyotyping analysis (SKY) in four individuals to assess chromosomal integrity. We also studied 38 granulocyte donors who received up to 42 doses of G-CSF and dexamethasone (Dex) using FISH for chromosomes 7 and 8. Results—We found no abnormalities in chromosomes 7 and 8 in G-CSF mobilized CD34+ cells when assessed by FISH or SKY, nor did we detect aneuploidy in G-CSF/Dex treated donors. Conclusion—G-CSF does not promote clinically detectable monosomy 7 or trisomy 8 aneuploidy in HSCT or granulocyte donors. These findings should be reassuring to healthy HSCT and granulocyte donors.

Iron deficiency (ID) affects billions of persons worldwide, and anemia develops when iron stores become insufficient to maintain normal erythropoiesis. Iron homeostasis in mammals is largely maintained by expression of a small hepatic protein named hepcidin.1 Hepcidin itself is regulated at the transcriptional and posttranscriptional levels by multiple extracellular signals related to the iron supply and the erythropoietic demands of the host, as well as by inflammatory states. ID results in a significant reduction in serum hepcidin as measured by mass spectroscopy2 and more recently by hepcidin immunoassay.3 Even in the absence of ID, anemia-related hypoxia4 and erythropoietin production inhibit hepcidin expression.5 In addition, in anemic states characterized by ineffective erythropoiesis, such as thalassemia and congenital dyserythropoiesis,6 inappropriate hepcidin down regulation results in severe iron overload. It was recently demonstrated that human erythroblasts secrete a cytokine named growth differentiation factor 15 (GDF15) that contributes to the inhibition of hepcidin in pathologic conditions.7 As a p53 target gene,8 it was proposed that GDF15 is secreted from apoptotic erythroblasts in clinical settings of ineffective erythropoiesis. However, GDF15 involvement in iron regulation in other clinical settings is largely unknown.

BACKGROUND: 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. RESULTS: 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. CONCLUSIONS: 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.

Background: Little is known about the early mechanisms mediating left ventricular (LV) diastolic dysfunction in patients with hereditary hemochromatosis (HH). However, the increased oxidative stress related to iron overload may be involved in this process, and strain rate (SR), a sensitive echocardiography-derived measure of diastolic function, may detect such changes. Aim: we evaluated the relationship between left ventricular diastolic function measured with tissue Doppler SR and oxidative stress in asymptomatic HH subjects and control normal subjects. Materials and Methods: Ninety-four consecutive visits of 43 HH subjects, age 30–74 (50 ± 10, mean ± SD), and 37 consecutive visits of 21 normal volunteers, age 30–63 (48 ± 8), were evaluated over a 3-year period. SR was obtained from the basal septum in apical four-chamber views. All patients had confirmed C282Y homozygosity, a documented history of iron overload, and were New York Heart Association functional class I. Normal volunteers lacked HFE gene mutations causing HH. Results: In the HH subjects, the SR demonstrated moderate but significant correlations with biomarkers of oxidative stress; however, no correlations were noted in normal subjects. The biomarkers of iron overload per se did not show significant correlations with the SR. Conclusion: Although our study was limited by the relatively small subject number, these results suggest that a possible role of oxidative stress to affect LV diastolic function in asymptomatic HH subjects and SR imaging may be a sensitive measure to detect that effect. (ECHOCARDIOGRAPHY, Volume 26, November 2009)

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.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 preprocedure 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 microg per kg and a uniform 480-microg 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 microg is as effective as weight-based dosing at 5 microg per kg. Donor ANC monitoring should be considered after serial granulocytapheresis procedures.

The combination of granulocyte-colony-stimulating factor (G-CSF) and dexamethasone is an effective granulocyte mobilization regimen. The short-term side effects of G-CSF are well studied, but the potential long-term effects of repeated G-CSF stimulation in unrelated volunteer granulocyte donors have not been reported.Donors who had received G-CSF three or more times for granulocytapheresis between 1994 and 2002 were identified and attempts were made to contact them if they were no longer active donors. They were matched with control platelet (PLT) donors for sex, age, and approximate number of cytapheresis donations. A health history was obtained and complete blood counts (CBCs) and C-reactive protein (CRP) determined where feasible.Ninety-two granulocyte donors were identified, and 83 of them were contacted. They contributed to 1120 granulocyte concentrates, or a mean of 13.5 granulocytapheresis procedures per donor (and a mean of 87.5 plateletpheresis procedures per donor). There was no difference in CBCs between the granulocyte donors and the control PLT donors. There was no difference in CRP between the two groups, and no difference in pre- and post-G-CSF CRP in a subset of 22 granulocyte donors. Predefined health events included malignancies, coronary artery disease, and thrombosis. At a median 10-year follow-up, there were seven such events in the granulocyte donors and five in the PLT donors.Although the number of granulocyte donors studied is small and continued surveillance of healthy individuals after G-CSF is prudent, our data suggest that G-CSF/dexamethasone stimulation appears to be safe.

INTRODUCTION Heart rate recovery (HRR) has become an important diagnostic and prognostic marker in recent years. Subjects with hereditary hemochromatosis (HH) demonstrate arterial wall changes that reduce compliance. Arterial compliance may influence HRR by altering baroreceptor discharge. The purpose of the present study is to examine differences in HRR between subjects with HH and healthy controls during treadmill (TM) and supine lower extremity ergometry (SLEE) exercise testing. METHODS Forty subjects with asymptomatic HH (27 men/13 women; mean age: 49.7 +/- 9.9 years) and 21 healthy controls (14 men/7 women; mean age: 47.8 +/- 8.4 years) participated in this study. Each subject underwent a symptom-limited 25-W Supine Lower Extremity Ergometry (SLEE) and Bruce TM exercise test within 1 week of each other. Heart rate recovery was the value obtained at 1 minute postexercise. Peak heart rate, systolic blood pressure, and the double product were also obtained during each exercise test. RESULTS Peak heart rate was significantly higher, whereas HRR and peak systolic blood pressure were significantly lower during TM compared with SLEE exercise testing in both groups (P < .01). A significantly lower HRR during SLEE in subjects with HH was the only significant difference between groups (35.4 +/- 9.0 vs. 29.2 +/- 8.5, P < .01). DISCUSSION Heart rate recovery was not significantly different between HH and control subjects during upright exercise. However, HRR was significantly lower during SLEE in HH subjects compared with controls. A higher venous return during SLEE may have allowed for differences in arterial compliance between groups to influence HRR.

There is no information available on left ventricular (LV) systolic function and the response to stress echocardiography in asymptomatic subjects with hereditary hemochromatosis (HH). To evaluate this topic, 43 asymptomatic subjects with HH homozygous for the C282Y HFE gene mutation (22 untreated subjects [group A] and 21 long-term treated subjects [group B]) were compared with 21 age- and gender-matched normal volunteers negative for HFE mutations. Contractile reserve, as a measure of LV systolic function, was assessed using continuous echocardiographic imaging and electrocardiography during supine bicycle exercise. Nineteen subjects in group A had repeat tests after 6 months of induction phlebotomy therapy to assess the effect of iron removal. Exercise performance and hemodynamic variables of supine bicycle exercise were comparable between subjects with HH and controls. LV contractile reserve of asymptomatic subjects with HH was not impaired at either a 75-W submaximal exercise level (mean +/- SD difference in ejection fraction from baseline 13.8 +/- 6.2%, 11.5 +/- 6.8%, and 13.4 +/- 7.8% in groups A, B, and C, respectively; p = NS for all by analysis of variance) or at peak exercise (difference in ejection fraction from baseline 18.9 +/- 6.9%, 18.4 +/- 7.8%, and 20.3 +/- 8.1% in groups A, B, and C, respectively; p = NS for all by analysis of variance). However, the incidence of abnormal ischemic stress electrocardiographic responses was more frequent in subjects with HH as a whole (33%) compared with normal subjects (10%). Stress imaging revealed no regional wall motion abnormalities, suggesting that these were false-positive results. Iron removal by induction phlebotomy did not affect stress echocardiographic performance. In conclusion, LV systolic function during exercise in asymptomatic subjects with HH is preserved, and 6-month induction phlebotomy does not affect stress echocardiographic performance.

BACKGROUND: Marked decreases in ionized magnesium (iMg) levels occur during large-volume leukapheresis (LVL); however, the effect of intravenous (IV) magnesium supplementation in this setting has not been carefully studied. STUDY DESIGN AND METHODS: Thirty healthy allogeneic peripheral blood progenitor cell donors receiving citrate anticoagulant with IV calcium prophylaxis were randomized to receive either IV magnesium (0.2 mg Mg per mL acid citrate dextrose-A) or placebo during LVL, with a double-blind design. RESULTS: Thirty subjects underwent 75 LVL pro- cedures, 37 with magnesium and 38 with placebo. Group characteristics were similar for sex, weight, citrate infusion rate (1.36 mg/kg/min vs. 1.37 mg/kg/min), and volume processed (16 L vs. 17 L). Serum iMg levels remained within the reference range with magnesium supplementation, but decreased 39 ± 11 percent below baseline (p

BACKGROUND: Anticoagulant-associated toxicity may exert significant effects on the safety and efficacy of large-volume leukapheresis (LVL) in children, however, few studies specifically address management of this issue. STUDY DESIGN AND METHODS: Seventy-four consecutive LVL procedures (mean, 4 blood volumes processed) in children weighing less than or equal to 30 kg (minimum, 10.9 kg) were analyzed. The first 21 procedures were evaluated retrospectively; 11 used heparin alone (Group I) and 10 used heparin plus reduced-dose ACD-A (whole blood to anticoagulant ratio ≥20:1) (Group II). The next 53 procedures were evaluated prospectively and used full-dose ACD-A (whole blood to anticoagulant ratio ≤13:1), intravenous divalent cation prophylaxis and no heparin; 11 used calcium alone (Group III) followed by 42 with calcium plus magnesium (Group IV). RESULTS: Seventy-four LVL (56 PBPC and 18 MNC) collections were performed in 38 subjects. One donor in Group I experienced a significant groin hematoma at the site of line placement. One donor each in Groups III and IV had mild paresthesias. Despite a mean citrate infusion rate of 2.6 mg per kg per minute, mean postapheresis serum potassium and ionized magnesium and calcium concentrations in Group IV declined by only 9, 8, and 4 percent, respectively, and stable levels of these variables were maintained 24 hours later. Postapheresis PLT counts declined significantly from baseline preapheresis levels in all groups (mean, 52% decrease). CONCLUSIONS: Use of full-dose citrate anticoagulant with prophylactic intravenous divalent cation infusion offers an effective and safe approach to management of anticoagulant-related toxicity in children undergoing LVL.

BACKGROUND: Persons with hemochromatosis constitute a plentiful and willing source of blood for transfusion. A program was established and evaluated for treating persons with hemochromatosis in a donor center and making their blood available for transfusion. STUDY DESIGN AND METHODS: Phlebotomy therapy was performed free of charge regardless of whether subjects met criteria for allogeneic donation. A Hb level of 12.5 g per dL was used as the threshold for performing phlebotomy, and decreases in the MCV were used to guide the endpoints of therapy. RESULTS: A total of 130 subjects were consecutively enrolled: 74 percent were homozygous for the C282Y mutation in the HFE gene, 76 percent met eligibility criteria for allogeneic donation, and 55 percent were previous blood donors. A median of 20 weekly or biweekly phlebotomies (range, 7-99) were performed before the MCV reached the targeted endpoint of 3 percent below baseline, at which time the ferritin level was less than 30 µg per L and the transferrin saturation was less than 30 percent. The median phlebotomy interval necessary to keep the MCV at this level during maintenance therapy was 10 weeks. No incident seroconversions for agents of transfusion-transmissible disease occurred during 1402 donations. All subjects testing positive for viral agents gave a prior history of deferrable risk. Twenty-seven months after starting the program, hemochromatosis donors were contributing 14 percent of the RBC units collected for allogeneic use. CONCLUSIONS: Hemochromatosis subjects can safely and significantly augment the allogeneic blood supply. Provision of phlebotomy therapy unrestricted by considerations of cost or suitability for donation can improve access to care and remove incentives for incomplete risk disclosure.

BACKGROUND: The effect of oral calcium (Ca) supplements in preventing citrate-induced symptoms during plateletpheresis was evaluated in a randomized, blinded, placebo-controlled trial. STUDY DESIGN AND METHODS: Twenty-three donors (12 men, 11 women) underwent four plateletpheresis procedures each, ingesting either 1 or 2 g of oral Ca carbonate or an equivalent placebo 30 minutes before donation. Ten of these subjects subsequently ingested 4 g of open-label Ca before a fifth procedure. All procedures were conducted at the same citrate infusion rate (1.5 mg/kg/min) for 90 minutes. RESULTS: Ingestion of 2 g of oral Ca resulted in a significant reduction in the severity of paresthesias and a significant, though modest, increase in serum ionized calcium (iCa), but no significant improvement in total symptom scores, compared to placebo. Minimal effects were seen with the 1-g dose. The two factors most highly correlated with development of severe symptoms were decreased levels of iCa and ionized magnesium (iMg) at 30 minutes into apheresis. Lower preapheresis serum albumin, creatinine, vitamin D, iMg, and total Mg concentrations were also significantly associated with symptoms. Women experienced more frequent and severe symptoms than men, however, gender was not associated with symptoms after adjustment for lower serum albumin, creatinine, and Mg levels. Ingestion of 4 g of Ca offered no improvement in symptoms or iCa levels compared with the 2-g dose. CONCLUSION: Prophylactic oral Ca was associated with modest improvements in citrate-induced symptoms and laboratory parameters. Baseline albumin and Mg levels were strongly predictive of the development of symptoms. In donors with a prior history of uncomfortable citrate-related effects, a 2-g oral Ca dose before apheresis is recommended.

BACKGROUND: The metabolic effects of oral calcium (Ca) supplementation during plateletpheresis were evaluated in a randomized, placebo-controlled trial. STUDY DESIGN AND METHODS: Twenty-three donors underwent four plateletpheresis procedures each, receiving in random order, elemental Ca (Ca) 1 or 2 g orally, or a corresponding placebo, 30 minutes before donation. Ten of these donors underwent a fifth procedure using a 4-g Ca dose. All procedures were performed at a fixed citrate infusion rate of 1.5 mg per kg per minute. RESULTS: Oral Ca induced dose-sensitive changes in parathyroid hormone (iPTH), total (tCa), and ionized (iCa) calcium levels. Compared to placebo, the greatest improvement in tCa and iCa levels occurred after the 2-g Ca dose (tCa of 73, 89, and 25% above placebo levels at 60 min, using 1, 2, and 4 g of oral Ca, respectively). Twenty-four hours after apheresis, serum tCa and iCa levels were higher, and iPTH levels lower, in donors who received oral Ca rather than placebo. Marked increases in urinary Ca and magnesium (Mg) excretion occurred at the completion of apheresis, were unaffected by Ca dose, and returned to baseline within 24 hours. Plateletpheresis also induced significant changes in serum alkaline phosphatase, 1,25-dihydroxyvitamin D, and osteocalcin levels immediately and at 24 hours after apheresis. CONCLUSION: Plateletpheresis induces marked acute metabolic effects, with sustained changes evident up to 24 hours after the completion of apheresis. Oral Ca supplementation exerts a significant but clinically modest impact on selected laboratory variables associated with these effects. Further studies are indicated to examine the long-term impact of plateletpheresis, with or without Ca supplementation, on donor Ca balance and bone density.

Summary. We report cell kinetics, yields and donation experiences of 20 demographically matched allogeneic peripheral blood stem cell (PBSC) donors who were prospectively assigned to undergo either a single 25 l or two consecutive daily 15 l (15 l × 2) apheresis procedures. Procedures were performed using prophylactic intravenous calcium administration after standard granulocyte colony-stimulating factor (GCSF) mobilization (10 μg/kg/d). Central line placements (two each), initial CD34 cell counts (0·077 vs 0·078 × 109/l) and yields (7·9 vs 8·1 × 108 CD34 cells) were similar in the two groups; however, 25 l donors spent significantly less time both in the clinic (7·5 vs 10·8 h) and with central venous catheters in place (8·5 vs 29·5 h) than 15 l × 2 donors. End-procedure platelet counts were below 100 × 109/l in one out of 10 25 l donors versus five out of 10 in 15 l × 2 donors (41%vs 53% mean decrease in platelet counts, P = 0·02). PBSC collection efficiency increased by 37% after 15 l of the 25-l volume had been processed, compared with no significant change during 15 l × 2 procedures. Results similar to these prospective findings were also observed in CD34 yields, symptoms and platelet counts in additional 25 l and 15 l procedures performed during the same period and evaluated retrospectively. This study indicates that a single 25-l apheresis procedure results in similar yields and symptoms, but less donor thrombocytopenia and inconvenience than two consecutive daily 15-l procedures.

BACKGROUND: Leukapheresis procedures are generally performed at citrate anticoagulation rates extrapolated from shorter plateletpheresis procedures. However, neither the metabolic effects nor the management of associated symptoms have been critically evaluated during leukapheresis in healthy donors. STUDY DESIGN AND METHODS: Symptom assessments (n = 315) and laboratory analyses (n = 49) were performed during 244 procedures performed with and 71 without prophylactic calcium (Ca) chloride or Ca gluconate given at a dose linked to the citrate infusion rate (1.0-2.2 mg/kg/min). RESULTS: During leukapheresis of 12 to 25 L processed, ionized Ca and ionized magnesium (Mg) decreased as much as 35 and 56 percent, respectively, each exhibiting a tight negative correlation with marked increases in serum citrate levels. Significant increases in urinary Ca and Mg excretion accompanied the renal excretion of a large citrate load. Serum divalent cation levels remained depressed 24 hours after leukapheresis. Symptoms were more frequent in donors who were women, had low initial total Mg levels, and underwent procedures in which larger volumes were processed at higher citrate infusion rates. Ca infusions reduced clinically significant paresthesias by 96 percent and also attenuated decreases in serum potassium. Ca chloride maintained higher Ca levels than Ca gluconate. CONCLUSIONS: Prophylactic Ca infusions safely attenuate the marked metabolic effects of citrate administration and promote faster, more comfortable, leukapheresis procedures.

Therapeutic phlebotomy is increasingly used in patients with transfusional siderosis to mitigate organ injury associated with iron overload (IO). Laboratory response variables and therapy duration are not well characterized in such patients.We retrospectively evaluated 99 consecutive patients undergoing therapeutic phlebotomy for either transfusional IO (TIO, n = 88; 76% had undergone hematopoietic transplantation) or nontransfusional indications (hyperferritinemia or erythrocytosis; n = 11). Complete blood cell count, serum ferritin (SF), transferrin saturation, and transaminases were measured serially. Phlebotomy goal was an SF level of less than 300 μg/L.Mean SF levels before phlebotomy among TIO and nontransfusional subjects were 3093 and 396 μg/L, respectively. Transfusion burden in the TIO group was 94 ± 108 (mean ± SD) RBC units; approximately half completed therapy with 24 ± 23 phlebotomies (range, 1-103). One-third were lost to follow-up. Overall, 15% had mild adverse effects, including headache, nausea, and dizziness, mainly during first phlebotomy. Prior transfusion burden correlated poorly with initial ferritin and total number of phlebotomies to target in the TIO group. However, number of phlebotomies to target was strongly correlated with initial SF (R(2) = 0.8; p0.0001) in both TIO and nontransfusional groups. ALT decreased significantly with serial phlebotomy in all groups (mean initial and final values, 61 and 39 U/L; p = 0.03).Initial SF but not transfusion burden predicted number of phlebotomies to target in patients with TIO. Despite good treatment tolerance, significant losses to follow-up were noted. Providing patients with an estimated phlebotomy number and follow-up duration, and thus a finite endpoint, may improve compliance. Hepatic function improved with iron offloading.

BACKGROUND: G-CSF with or without dexamethasone is becoming the standard agent for mobilizing granulocytes for transfusion. The purpose of this study was to determine if the toxicities of G--CSF with or without dexamethasone are offset by greater collection yields and to define the minimum interval that should separate sequential collections. STUDY DESIGN AND METHODS: Twenty donors were studied on three occasions. They were given either dexamethasone (8 mg, by mouth) plus a placebo injection, G--CSF (5 microg/kg, given subcutaneously) plus placebo capsules, or G--CSF plus dexamethasone. Granulocytes were collected by apheresis. A donor symptom survey was administered, and cell counts and blood chemistries were assessed before collection and 1, 2, 7, 14, 21, 28, and 35 days after collection. RESULTS: More granulocytes were collected when G--CSF was given than when dexamethasone was given (41.1 +/- 20.4 x 10(9) vs. 21.0 +/- 10.0 x 10(9); p

Granulocyte-colony-stimulating factor (G-CSF)-mobilized autologous hematopoietic progenitor cells (HPCs) may be collected by apheresis of patients with chronic granulomatous disease (CGD) and severe combined immunodeficiency (SCID) for use in gene therapy trials. CD34+ cell mobilization has not been well characterized in such patients.We retrospectively evaluated CD34+ cell mobilization and collection in 73 consecutive CGD and SCID patients and in 99 age-, weight-, and G-CSF dose-matched healthy allogeneic controls.In subjects aged not more than 20 years, Day 5 preapheresis circulating CD34+ counts were significantly lower in CGD and SCID patients than in controls; mean peak CD34+ cell counts were 58 × 10(6) , 64 × 10(6) , and 87 × 10(6) /L, respectively (p = 0.01). The SCIDs had lower CD34+ collection efficiency than CGDs and controls; mean efficiencies were 40, 63, and 57%, respectively (p = 0.003). In subjects aged more than 20 years, the CGDs had significantly lower CD34+ cell mobilization than controls; mean peak CD34+ cell counts were 41 × 10(6) and 113 × 10(6) /L, respectively (p 0.0001). In a multivariate analysis, lower erythrocyte sedimentation rate (ESR) at mobilization was significantly correlated with better CD34+ cell mobilization (p = 0.007). In SCIDs, CD34 collection efficiency was positively correlated with higher red blood cell (RBC) indices (mean RBC volume, R(2) = 0.77; mean corpuscular hemoglobin [Hb], R(2) = 0.94; mean corpuscular Hb concentration, R(2) = 0.7; p 0.007) but not Hb.CGD and SCID populations are characterized by significantly less robust CD34+ HPC mobilization than healthy controls. The presence of active inflammation or infection as suggested by an elevated ESR may negatively impact mobilization. Among SCIDs, markedly reduced CD34 collection efficiencies were related to iron deficiency, wherein decreased RBC size and density may impair apheresis cell separation mechanics.

Hereditary hemochromatosis (HH) is the most common metabolic genetic disorder and affects approximately one in 180 members of the Caucasian population.1,2 We have previously reported that the aerobic exercise capacity of cardiac asymptomatic HH subjects was similar to that of age-gender matched normal volunteers at one cross sectional time point.3 Iron overload, which is induced by HH, has been shown to cause diastolic and systolic dysfunction4 and the long-term effect of HH on aerobic exercise capacity has not been reported, although this would be of interest for healthcare professionals. It is of special interest for those who monitor athletes with HH since a higher frequency of HFE (hemochromatosis gene) mutations which cause HH is reported among endurance runners.5 In addition, the long-term effectiveness of conventional phlebotomy therapy in preventing HH associated complications such as hypothyroidism, liver malignancy, arthritis, systolic and diastolic cardiac dysfunction, and cardiac arrhythmias is not well elucidated.6–8 Likewise, the long-term therapeutic benefit of conventional phlebotomy therapy on aerobic exercise capacity has not been reported. We had an opportunity to serially track the aerobic exercise capacity of cardiac asymptomatic subjects with HH, whose baseline observations were reported in this journal, under NHLBI-sponsored “Heart Study of Hemochromatosis (NCT00068159)” over a 5-year span. Thus, we now report on the changes in aerobic exercise capacity at 5-year follow up in the HH subjects who received conventional phlebotomies over this period in comparison with volunteer control subjects.

It is not well known whether systemic iron overload per se in hereditary hemochromatosis (HH) is associated with cardiac arrhythmias before other signs and symptoms of cardiovascular disease occur. In the present study, we examined the incidence of cardiac arrhythmia in cardiac asymptomatic subjects with HH (New York Heart Association functional class I) and compared it to that in age- and gender-matched normal volunteers. The 42 subjects with HH and the 19 normal control subjects were recruited through the National Heart, Lung, and Blood Institute-sponsored "Heart Study of Hemochromatosis." They completed 48-hour Holter electrocardiography ambulatory monitoring at the baseline evaluation. The subjects with HH were classified as newly diagnosed (group A) and chronically treated (group B) subjects. All subjects with HH had C282Y homozygosity, and the normal volunteers lacked any HFE gene mutations known to cause HH. Although statistically insignificant, the incidence of ventricular and supraventricular ectopy tended to be greater in the combined HH groups than in the controls. Supraventricular ectopy was more frequently noted in group B compared to in the controls (ectopy rate per hour 11.1 ± 29.9 vs 1.5 ± 3.5, p < 0.05, using the Kruskal-Wallis test). No examples of heart block, other than first-degree atrioventricular node block, were seen in any of the subjects. The incidence of cardiac arrhythmias was not significantly reduced after 6 months of intensive iron removal therapy in the group A subjects. No life-threatening arrhythmias were observed in our subjects with HH. In conclusion, our data suggest that the incidence of cardiac arrhythmias is, at most, marginally increased in asymptomatic subjects with HH. A larger clinical study is warranted to further clarify our observation.

After administration of granulocyte colony-stimulating factor (G-CSF), there is a marked, albeit transient, drop in circulating neutrophils. To determine the role of leukocyte integrins in this disappearance, a dog having canine leukocyte adhesion deficiency (CLAD) or CLAD dogs who had undergone gene correction either by matched littermate allogeneic transplant or autologous gene therapy were evaluated. Shortly after G-CSF administration, a dramatic, yet transient, neutropenia was observed in the control littermates. This neutropenia was not as marked in the CLAD dogs. In all instances, it was CD18+ neutrophils that preferentially egressed from the circulation. The association of CD18 with this rapid loss suggested leukocyte integrin activation after G-CSF administration. To determine the activation status of the integrin, a monoclonal antibody recognizing the activated α-subunit cation binding domain (mAb24) was used to evaluate human leukocytes after G-CSF administration. Mirroring the dramatic decrease in circulating neutrophil numbers, there was a dramatic and specific increase in the activation of the α-subunit after G-CSF expression on polymorphonuclear leukocytes. This activation, like the drop in neutrophil count, was transient. These results demonstrate that the leukocyte integrin on circulating neutrophils is transiently activated after G-CSF administration and mediates the transient neutropenia observed after G-CSF administration.

Reports of Monosomy 7 in patients receiving granulocyte-colony-stimulating factor (G-CSF) have raised concerns that this cytokine may promote genomic instability. However, there are no studies addressing whether repeated administration of G-CSF produces Monosomy 7 aneuploidy in healthy donors.We examined Chromosomes 7 and 8 by fluorescent in situ hybridization (FISH) in CD34+ cells from 35 healthy hematopoietic stem cell transplant (HSCT) donors after G-CSF administration for 5 days and by spectral karyotyping analysis (SKY) in four individuals to assess chromosomal integrity. We also studied 38 granulocyte donors who received up to 42 doses of G-CSF and dexamethasone (Dex) using FISH for Chromosomes 7 and 8.We found no abnormalities in Chromosomes 7 and 8 in G-CSF-mobilized CD34+ cells when assessed by FISH or SKY, nor did we detect aneuploidy in G-CSF- and Dex-treated donors.G-CSF does not promote clinically detectable Monosomy 7 or Trisomy 8 aneuploidy in HSCT or granulocyte donors. These findings should be reassuring to healthy HSCT and granulocyte donors.

Low serum hepcidin levels provide a physiologic response to iron demand in patients with iron deficiency (ID). Based on a discovery of suppressed hepcidin expression by a cytokine named growth differentiation factor 15 (GDF15), it was hypothesized that GDF15 may suppress hepcidin expression in humans with ID due to blood loss.To test this hypothesis, GDF15 and hepcidin levels were measured in peripheral blood from subjects with iron-deficient erythropoiesis before and after iron supplementation.Iron variables and hepcidin levels were significantly suppressed in iron-deficient blood donors compared to healthy volunteers. However, ID was not associated with elevated serum levels of GDF15. Instead, iron-deficient subjects' GDF15 levels were slightly lower than those measured in the control group of subjects (307 +/- 90 and 386 +/- 104 pg/mL, respectively). Additionally, GDF15 levels were not significantly altered by iron repletion.ID due to blood loss is not associated with a significant change in serum levels of GDF15.

Aims In a blinded, placebo-controlled study, we investigated whether intracoronary infusion of autologous mononuclear cells from granulocyte colony-stimulating factor (G-CSF)-mobilized apheresis product or bone marrow (BM) improved sensitive outcome measures in a swine model of large myocardial infarction (MI). Methods and results Four days after left anterior descending (LAD) occlusion and reperfusion, cells from BM or apheresis product of saline- (placebo) or G-CSF-injected animals were infused into the LAD. Large infarcts were created: baseline ejection fraction (EF) by magnetic resonance imaging (MRI) of 35.3 ± 8.5%, no difference between the placebo, G-CSF, and BM groups ( P = 0.16 by ANOVA). At 6 weeks, EF fell to a similar degree in the placebo, G-CSF, and BM groups (−7.9 ± 6.0, −8.5 ± 8.8, and −10.9 ± 7.6%, P = 0.78 by ANOVA). Left ventricular volumes and infarct size by MRI deteriorated similarly in all three groups. Quantitative positron emission tomography (PET) demonstrated significant decline in fluorodeoxyglucose uptake rate in the LAD territory at follow-up, with no histological, angiographic, or PET perfusion evidence of functional neovascularization. Immunofluorescence failed to demonstrate transdifferentiation of infused cells. Conclusion Intracoronary infusion of mononuclear cells from either BM or G-CSF-mobilized apheresis product may not improve or limit deterioration in systolic function, adverse ventricular remodelling, infarct size, or perfusion in a swine model of large MI.

Purpose: The exercise capacity of cardiac asymptomatic subjects with hereditary hemochromatosis (HH) has not been well described. In this study, we tested whether the iron overload associated with HH affected exercise capacity with a case control study design. Methods: Forty-three HH and 21 normal control subjects who were New York Heart Association functional class I underwent metabolic stress testing using the Bruce protocol at the clinical center of the National Institutes of Health. Exercise capacity was assessed with minute ventilation (V?E), oxygen uptake (V?O2), and carbon dioxide production (V?CO2) using a breath-by-breath respiratory gas analyzer. Results: The exercise capacity of HH subjects was not statistically different from that of control subjects (exercise time 564 ± 135 vs 673 ± 175 s, P = 0.191; peak V?O2 29.6 ± 6.4 vs 32.5 ± 6.7 mL·kg-1·min-1, P = 0.109; ventilatory threshold 19.0 ± 3.4 vs 21.0 ± 5.0 mL·min-1·kg-1, P = 0.099; data are for HH vs control subjects). Ventilatory efficiency was comparable between groups (V?E/V?CO2 slope 23.7 ± 3.2 vs 23.4 ± 4.2, P = 0.791). No significant correlation between the markers of iron levels and the markers of exercise capacity was noted. Iron depletion by 6-month phlebotomy therapy in 18 subjects who were newly diagnosed did not affect exercise testing variables (exercise time 562 ± 119 vs 579 ± 118 s, P = 0.691; peak V?O2 29.5 ± 3.7 vs 29.1 ± 4.7 mL·kg-1·min-1, P = 0.600; ventilatory threshold 18.5 ± 2.8 vs 17.9 ± 3.8 mL·kg-1·min-1, P = 0.651; data are from before and after phlebotomy therapy). Abnormal ischemic electrocardiographic responses and complex arrhythmias were more frequently seen in HH subjects. Conclusions: The aerobic exercise capacity of asymptomatic HH subjects seems not to be statistically different from that of normal subjects. The iron levels do not seem to affect exercise capacity in asymptomatic HH subjects.

Exercise performance and electrocardiogram (ECG) responses in hereditary hemochromatosis (HH) subjects who are New York Heart Association Functional Class I are unknown. Thus, we evaluated exercise...

Anticoagulant-associated toxicity may exert significant effects on the safety and efficacy of large-volume leukapheresis (LVL) in children, however, few studies specifically address management of this issue.Seventy-four consecutive LVL procedures (mean, 4 blood volumes processed) in children weighing less than or equal to 30 kg (minimum, 10.9 kg) were analyzed. The first 21 procedures were evaluated retrospectively; 11 used heparin alone (Group I) and 10 used heparin plus reduced-dose ACD-A (whole blood to anticoagulant ratioor =20:1) (Group II). The next 53 procedures were evaluated prospectively and used full-dose ACD-A (whole blood to anticoagulant ratioor =13:1), intravenous divalent cation prophylaxis and no heparin; 11 used calcium alone (Group III) followed by 42 with calcium plus magnesium (Group IV).Seventy-four LVL (56 PBPC and 18 MNC) collections were performed in 38 subjects. One donor in Group I experienced a significant groin hematoma at the site of line placement. One donor each in Groups III and IV had mild paresthesias. Despite a mean citrate infusion rate of 2.6 mg per kg per minute, mean postapheresis serum potassium and ionized magnesium and calcium concentrations in Group IV declined by only 9, 8, and 4 percent, respectively, and stable levels of these variables were maintained 24 hours later. Postapheresis PLT counts declined significantly from baseline preapheresis levels in all groups (mean, 52% decrease).Use of full-dose citrate anticoagulant with prophylactic intravenous divalent cation infusion offers an effective and safe approach to management of anticoagulant-related toxicity in children undergoing LVL.

Persons with hemochromatosis constitute a plentiful and willing source of blood for transfusion. A program was established and evaluated for treating persons with hemochromatosis in a donor center and making their blood available for transfusion.Phlebotomy therapy was performed free of charge regardless of whether subjects met criteria for allogeneic donation. A Hb level of 12.5 g per dL was used as the threshold for performing phlebotomy, and decreases in the MCV were used to guide the endpoints of therapy.A total of 130 subjects were consecutively enrolled: 74 percent were homozygous for the C282Y mutation in the HFE gene, 76 percent met eligibility criteria for allogeneic donation, and 55 percent were previous blood donors. A median of 20 weekly or biweekly phlebotomies (range, 7-99) were performed before the MCV reached the targeted endpoint of 3 percent below baseline, at which time the ferritin level was less than 30 microg per L and the transferrin saturation was less than 30 percent. The median phlebotomy interval necessary to keep the MCV at this level during maintenance therapy was 10 weeks. No incident seroconversions for agents of transfusion-transmissible disease occurred during 1402 donations. All subjects testing positive for viral agents gave a prior history of deferrable risk. Twenty-seven months after starting the program, hemochromatosis donors were contributing 14 percent of the RBC units collected for allogeneic use.Hemochromatosis subjects can safely and significantly augment the allogeneic blood supply. Provision of phlebotomy therapy unrestricted by considerations of cost or suitability for donation can improve access to care and remove incentives for incomplete risk disclosure.

The effect of oral calcium (Ca) supplements in preventing citrate-induced symptoms during plateletpheresis was evaluated in a randomized, blinded, placebo-controlled trial.Twenty-three donors (12 men, 11 women) underwent four plateletpheresis procedures each, ingesting either 1 or 2 g of oral Ca carbonate or an equivalent placebo 30 minutes before donation. Ten of these subjects subsequently ingested 4 g of open-label Ca before a fifth procedure. All procedures were conducted at the same citrate infusion rate (1.5 mg/kg/min) for 90 minutes.Ingestion of 2 g of oral Ca resulted in a significant reduction in the severity of paresthesias and a significant, though modest, increase in serum ionized calcium (iCa), but no significant improvement in total symptom scores, compared to placebo. Minimal effects were seen with the 1-g dose. The two factors most highly correlated with development of severe symptoms were decreased levels of iCa and ionized magnesium (iMg) at 30 minutes into apheresis. Lower preapheresis serum albumin, creatinine, vitamin D, iMg, and total Mg concentrations were also significantly associated with symptoms. Women experienced more frequent and severe symptoms than men, however, gender was not associated with symptoms after adjustment for lower serum albumin, creatinine, and Mg levels. Ingestion of 4 g of Ca offered no improvement in symptoms or iCa levels compared with the 2-g dose.Prophylactic oral Ca was associated with modest improvements in citrate-induced symptoms and laboratory parameters. Baseline albumin and Mg levels were strongly predictive of the development of symptoms. In donors with a prior history of uncomfortable citrate-related effects, a 2-g oral Ca dose before apheresis is recommended.

BACKGROUND The circulating CD34 count is a reliable predictor of peripheral blood progenitor cell (PBPC) yields in subjects with a vigorous mobilization response to G-CSF, however, the value of this parameter in poor mobilizers is uncharacterized. STUDY DESIGN AND METHODS Consecutive PBPC procedures (n = 81) with preapheresis CD34 counts less than 20 per microL (poor mobilizers) were compared with an equal number of good mobilizers (preapheresis CD34 counts > or =20/microL). G-CSF was administered at standard doses (10 microg/kg/day). RESULTS CD34 yields correlated strongly with preapheresis CD34 counts in both good and poor mobilizers and were higher in allogeneic than autologous donors. For a standard 75-kg recipient, a CD34 cell dose of greater than 2 x 10(6) per kg was never achieved in less than two 15-L procedures if the preapheresis CD34 count was less than 8 per microL. Preapheresis WBC and MNC counts were lower in poor than in good mobilizers (28.4 vs. 43.0 and 3.25 vs. 5.01 x 10(3)/microL, respectively, p < 0.0001). Total WBC counts correlated more strongly with preapheresis CD34 counts, total CD34 yields, and CD34 yields per L processed in good mobilizers (R = 0.50, R = 0.44, and R = 0.42, respectively) than in poor mobilizers (R = 0.22, R = 0.02, and R = 0.01, respectively), whereas total MNC counts correlated more strongly with these parameters in poor (R = 0.38, R = 0.23, and R = 0.27, respectively) than in good mobilizers (R = 0.04, R = 0.13, and R = 0.16, respectively). CONCLUSION CD34 cell yields correlate strongly with preapheresis CD34 counts. Based on this analysis, a CD34 count greater than or equal to 8 per microL is the threshold for performing PBPC collections in our institution.

We report cell kinetics, yields and donation experiences of 20 demographically matched allogeneic peripheral blood stem cell (PBSC) donors who were prospectively assigned to undergo either a single 25 l or two consecutive daily 15 l (15 l x 2) apheresis procedures. Procedures were performed using prophylactic intravenous calcium administration after standard granulocyte colony-stimulating factor (GCSF) mobilization (10 microg/kg/d). Central line placements (two each), initial CD34 cell counts (0.077 vs 0.078 x 10(9)/l) and yields (7.9 vs 8.1 x 10(8) CD34 cells) were similar in the two groups; however, 25 l donors spent significantly less time both in the clinic (7.5 vs 10.8 h) and with central venous catheters in place (8.5 vs 29.5 h) than 15 l x 2 donors. End-procedure platelet counts were below 100 x 10(9)/l in one out of 10 25 l donors versus five out of 10 in 15 l x 2 donors (41%vs 53% mean decrease in platelet counts, P = 0.02). PBSC collection efficiency increased by 37% after 15 l of the 25-l volume had been processed, compared with no significant change during 15 l x 2 procedures. Results similar to these prospective findings were also observed in CD34 yields, symptoms and platelet counts in additional 25 l and 15 l procedures performed during the same period and evaluated retrospectively. This study indicates that a single 25-l apheresis procedure results in similar yields and symptoms, but less donor thrombocytopenia and inconvenience than two consecutive daily 15-l procedures.

Mobilization of hematopoietic progenitor cells (HPC) for subsequent autologous transplantation is difficult in patients with plasma cell myeloma (PCM) due to poor marrow reserve. Targeted HPC yields are generally not achieved in a single apheresis procedure without use of plerixafor as a supplement to standard filgrastim. Strategies to limit use of plerixafor, due to its expense, to cases of poor CD34 mobilization have been developed, but their applicability in patients receiving the novel induction regimen carfilzomib-lenalidomide-dexamethasone (CRD) (Blood 2012;120:1801) has not been described. We prospectively studied the CD34 cell mobilization responses of PCM patients following CRD induction, using a CD34 cell predictive algorithm to determine when plerixafor should be added to the mobilization regimen. Thirty patients, including 23 with PCM and 7 with smoldering PCM, mean age 55 (range 40-72), 47% male, received 4 to 7 cycles of CRD (median, 5 cycles), with the last dose of lenalidomide given at least one week prior to mobilization. Filgrastim 10-16 mcg/kg/day was given as a single evening dose for 5 days, with circulating CD34 count assessed 12 hours after the 4th dose. The pre-apheresis CD34 count after the 5th dose of filgrastim was predicted to be 10% greater than that after the 4th dose; this prediction was validated with an actual pre-apheresis CD34 count obtained the following day. Prior mobilization data derived from healthy HPC apheresis donors was used to generate a regression formula, y=0.45x+0.86, where x=the pre-apheresis circulating CD34 count after the 5th dose of filgrastim, and y=the expected yield of the apheresis procedure, expressed as millions of CD34 cells harvested per liter processed. Targeted yield was ≥ 4 x 106 CD34 cells/kg, with minimum acceptable yield ≥ 2 x 106 CD34 cells/kg. Plerixafor 240 mcg/kg was given with the 5th dose of filgrastim, 8-10 hours prior to apheresis, if the regression equation predicted a CD34 cell yield of < 4 x 106 CD34 cells/kg in a single procedure with a maximum of 30 liters processed. The actual volume processed was based on the stat blood CD34 count drawn immediately prior to apheresis. Procedures were performed on the Cobe Spectra device; continuous intravenous calcium was used to mitigate citrate toxicity. Central lines were required in 67% of subjects. Mean CD34 cell count in the entire group after the 4th dose of filgrastim was 29/uL (range 2-88/uL). Using the regression formula as a guide, 17/30 (57%) of patients received plerixafor. CD34 counts increased 4.2-fold in patients receiving plerixafor, from 15 ± 9/uL (m ± SD) on the day prior to apheresis to 53 ± 30/uL immediately pre-apheresis; CD34 counts did not change in patients who received filgrastim alone (from 48 ± 17/uL to 45 ± 19/uL). Guided by the stat pre-apheresis CD34 count, the volume processed in the first apheresis procedure was the same, 23 ± 7 (range 12-30) liters, with or without plerixafor. CD34 cells were collected with 72 ± 14% efficiency. First-procedure CD34 cell yields were 6.4 ± 2.5 x 106/kg (range 2.5-10.1) with supplemental plerixafor vs 5.8 ± 2.5 x 106/kg (range 1.1-9.3) with filgrastim alone. Only 2/30 patients underwent a second procedure; neither received plerixafor prior to the first procedure, and both received it prior to the second. In one patient, criteria for plerixafor administration were met, but the drug was inadvertently not given prior to the first procedure; in the second patient, an unexpectedly low pre-apheresis CD34 count was traced to inadequate self-administration of the 5th dose of filgrastim. All 30 patients achieved the minimum CD34 collection goal of ≥ 2 x 106 cells/kg and 29/30 did this in one procedure. The higher targeted collection goal of ≥ 4 x 106 CD34 cells/kg was achieved in a single procedure by 76% of patients in both the plerixafor group and the filgrastim-alone group. There was a trend for higher cumulative lenalidomide and carfilzomib doses to be associated with lower CD34 mobilization responses to filgrastim. Induction treatment with CRD does not appear to impair HPC mobilization response to filgrastim in patients with PCM, compared to older regimens. An algorithm that uses the CD34 cell count after 4 doses of filgrastim to predict the following day’s pre-apheresis CD34 count and thus determine whether plerixafor supplementation is needed, was useful in identifying the 40% of CRD-treated myeloma patients who do not need plerixafor. Disclosures: No relevant conflicts of interest to declare.

Hematopoietic progenitor cells (HPCs) collected by apheresis of G-CSF-stimulated donors have surpassed bone marrow as the predominant graft source for hematopoietic stem cell transplantation in adults. Among healthy allogeneic donors, demographic characteristics (age, sex, and BMI) and baseline hematologic parameters have been shown to affect HPC mobilization, leading to significant variability in peak levels of CD34 cell egress into the blood and in quantity of CD34 cells harvested by apheresis. Racial differences in G-CSF-mediated HPC mobilization are less well characterized. Benign physiologic neutropenia is common among healthy African Americans (AAs), and may be due to decreased stem cell reserve, fewer G-CSF receptors, or Duffy (null) blood group antigen-mediated decrease in leukocyte trafficking into the circulation. However, preliminary studies have shown relatively robust CD34+ cell mobilization among non-Caucasians given G-CSF (Vasu et al., Blood 2006). We retrospectively analyzed 1,096 consecutive healthy allogeneic related and unrelated first-time donors who self-characterized their race as AA or Caucasian. They underwent G-CSF (filgrastim, Neupogen, Amgen) stimulated HPC collection by leukapheresis from April 1999 to May 2013. G-CSF dose ranged from 10-16 mcg/kg, given daily for 5 days. An unstimulated leukapheresis procedure for lymphocyte collection was performed in the 7 days preceding G-CSF in 336 subjects. Apheresis procedures were performed on the CS-3000 Plus or COBE Spectra device. Baseline lab data included CBC, serologic blood group antigen typing, and Hb electrophoresis in AA donors. CD34+ cell counts were performed on peripheral blood immediately pre-apheresis (2 hours after the 5th dose of G-CSF) and on the apheresis product. Values are given as mean ± SD. All AA (n=215) and Caucasian donors (n=881) with complete data sets were included. Sex ratio was similar among the groups (45 vs 52% male; p=0.09). AAs were younger (39 vs 43 yrs, p=0.001) and had greater weight (86 vs 81 kg, p=0.001) and BMI (30 vs 27; p African Americans demonstrated significantly more robust CD34 mobilization responses to G-CSF than Caucasians. The effect was independent of age, BMI, HbS and other variables, and occurred despite physiologically lower neutrophil counts among AAs. A ceiling effect in response to increased doses of G-CSF (>10 mcg/kg) was seen in AAs but not in Caucasians, suggesting that dose titration based on race might be used to optimize HPC yields. Further evaluation of race-associated genetic polymorphisms in relation to G-CSF pharmacokinetics may help improve G-CSF dosing strategies. Disclosures: No relevant conflicts of interest to declare.

Abstract 2283 Background: Pica and restless legs syndrome (RLS) are associated with iron depletion and deficiency. Pica refers to the compulsive craving for and persistent consumption of non-nutritive substances. Pagophagia, the pathological consumption of ice, is a specific pica strongly associated with iron deficiency. RLS is a neurological movement disorder characterized by uncomfortable sensations in the lower extremities, with a compelling urge to move the extremities to relieve the discomfort. Primary RLS is a central nervous system disorder; however, secondary RLS may be caused or exacerbated by iron deficiency. The purpose of this study was to prospectively assess the prevalence of pica and RLS in blood donors presenting to a hospital-based donor center, to correlate the findings with donor hemoglobin and iron levels, and to study the effects of oral iron replacement on the resolution of symptoms. Methods: During a 39-month period, 1236 blood donors deferred for fingerstick hemoglobin Results: Pica was reported in 11% of donors with iron depletion/deficiency, compared with 4% of iron-replete donors (p Conclusion: The presence of pica is highly predictive of iron depletion/deficiency in blood donors; however, RLS lacks a strong correlation in this population. Screening questions for pica, in particular pagophagia, may be useful in the ascertainment of iron depletion and deficiency in blood donors and may identify those who would benefit from oral iron therapy. Disclosures: No relevant conflicts of interest to declare.