Francis S. Morrison MD-Tribute to an apheresis leader.

Francis S. Morrison MD was among the early developers and promoters of the American Society for Apheresis (ASFA). His work was pivotal in creating a lasting institutional structure from which American apheresis medical practice would develop decades after his death. Francis Morrison is honored each year at the ASFA annual meeting as ASFA awards the Francis S. Morrison MD Memorial Award Lecture to an individual who stands out as among its most accomplished members. This tribute seeks to describe the person and the key accomplishments of Francis S. Morrison in the historical context of a time when the future of apheresis medicine was uncertain.

Antibodies against biotin-labeled red blood cells can shorten posttransfusion survival.

BACKGROUND: In hematologic and transfusion medicine research, measurement of red blood cell (RBC) in vivo kinetics must be safe and accurate. Recent reports indicate use of biotin-labeled RBC (BioRBC) to determine red cell survival (RCS) offers substantial advantages over 51 Cr and other labeling methods. Occasional induction of BioRBC antibodies has been reported. STUDY DESIGN AND METHODS: To investigate the causes and consequences of BioRBC immunization, we reexposed three previously immunized adults to BioRBC and evaluated the safety, antibody emergence, and RCS of BioRBC. RESULTS: BioRBC re-exposure caused an anamnestic increase of plasma BioRBC antibodies at 5-7 days; all were subclass IgG1 and neutralized by biotinylated albumin, thus indicating structural specificity for the biotin epitope. Concurrently, specific antibody binding to BioRBC was observed in each subject. As biotin label density increased, the proportion of BioRBC that bound increased antibody also increased; the latter was associated with proportional accelerated removal of BioRBC labeled at density 6 µg/mL. In contrast, only one of three subjects exhibited accelerated removal of BioRBC density 2 µg/mL. No adverse clinical or laboratory events were observed. Among three control subjects who did not develop BioRBC antibodies following initial BioRBC exposure, re-exposure induced neither antibody emergence nor accelerated BioRBC removal. DISCUSSION: We conclude re-exposure of immunized subjects to BioRBC can induce anamnestic antibody response that can cause an underestimation of RCS. To minimize chances of antibody induction and underestimation of RCS, we recommend an initial BioRBC exposure volume of ≤10 mL and label densities of ≤18 µg/mL.

WBC alloimmunization: effects on the laboratory and clinical endpoints of therapeutic granulocyte transfusions.

BACKGROUND: Although the subject of many previous studies, the importance of white blood cell (WBC) alloimmunization in granulocyte transfusion therapy has not been settled. In this study, we report the results of the effects of WBC antibodies in the RING (Resolving Infection in Neutropenia with Granulocytes) study, a randomized controlled trial comparing the efficacy of daily granulocyte transfusion therapy plus antimicrobials versus antimicrobials alone; the primary outcome results have been published previously. STUDY DESIGN AND METHODS: One hundred fourteen subjects were enrolled in the study. Serum samples for WBC antibody determination were obtained from each subject at baseline and at 2 and 6 weeks. One hundred subjects had at least one antibody test result. Samples were tested for human leukocyte antigen (HLA) Class I and Class II antibodies as well as for granulocyte-specific antibodies using granulocyte agglutination and immunofluorescence techniques. All testing was performed at a central laboratory. RESULTS: Baseline WBC alloimmunization was modest, depending somewhat on the assay. Seroconversion during the study was slightly higher in the granulocyte transfusion arm, but the differences were not statistically significant. There was no demonstrable effect of the presence of alloimmunization on the primary outcome (survival and microbial response at 42 days), the occurrence of transfusion reactions (either overall or pulmonary), or posttransfusion neutrophil increments. CONCLUSION: The presence or development of WBC antibodies had no demonstrable effect on any clinical aspect of granulocyte transfusion therapy. It appears that, at least in the patient population studied, there is no evidence suggesting need for concern about recipient WBC alloimmunization when prescribing granulocyte transfusions.

Red blood cell alloimmunization in sickle cell disease: assessment of transfusion protocols during two time periods.

BACKGROUND: Prevention of red blood cell (RBC) alloimmunization in patients with sickle cell disease (SCD) focuses on phenotypic RBC matching. We assessed alloimmunization among transfused patients with SCD after implementing leukoreduction and prophylactic antigen matching (PAM). STUDY DESIGN AND METHODS: Retrospective review of transfusion and medical records for SCD patients 18 months to 81 years of age was performed covering two 5-year periods: Period 1, no PAM, occasional leukoreduction, and Period 2, consistent leukoreduction and extended PAM (Rh, Kell, S, Fy, Jk) for patients already alloimmunized. Patients transfused in Period 1 were excluded from Period 2. RESULTS: A total of 293 patients were transfused in Period 1 and 183 in Period 2. Median time between first sample and last type and screen after transfusion was 2.12 years in Period 1 and 1.03 years in Period 2. Initial alloimmunization prevalence was lower in Period 2 (26.2%) versus Period 1 (37.5%) and after subsequent transfusions in Period 2 (23.8%) versus Period 1 (45.7%), although without significant difference after adjusting for number of units transfused, percentage of leukoreduced RBCs, sex, and age. Alloimmunized patients received more nonleukoreduced RBCs in Period 1 than nonalloimmunized. Patients transfused during inflammatory conditions were not significantly more likely to become alloimmunized. CONCLUSIONS: The prevalence of initial and subsequent RBC alloimmunization in Period 2 was lower than that in Period 1; however, overall prevalence remained high. We recommend leukoreduced, hemoglobin S-negative Rh and Kell PAM RBCs for transfusion of patients with SCD. Component and recipient factors affecting alloimmunization should be studied further.

In premature infants there is no decrease in 24-hour posttransfusion allogeneic red blood cell recovery after 42 days of storage.

BACKGROUND: Critically ill preterm very-low-birthweight (VLBW) neonates (birthweight ≤ 1.5 kg) frequently develop anemia that is treated with red blood cell (RBC) transfusions. Although RBCs transfused to adults demonstrate progressive decreases in posttransfusion 24-hour RBC recovery (PTR24 ) during storage-to a mean of approximately 85% of the Food and Drug Administration-allowed 42-day storage-limited data in infants indicate no decrease in PTR24 with storage. STUDY DESIGN AND METHODS: We hypothesized that PTR24 of allogeneic RBCs transfused to anemic VLBW newborns: 1) will be greater than PTR24 of autologous RBCs transfused into healthy adults and 2) will not decrease with increasing storage duration. RBCs were stored at 4°C for not more than 42 days in AS-3 or AS-5. PTR24 was determined in 46 VLBW neonates using biotin-labeled RBCs and in 76 healthy adults using 51 Cr-labeled RBCs. Linear mixed-model analysis was used to estimate slopes and intercepts of PTR24 versus duration of RBC storage. RESULTS: For VLBW newborns, the estimated slope of PTR24 versus storage did not decrease with the duration of storage (p = 0.18) while for adults it did (p < 0.0001). These estimated slopes differed significantly in adults compared to newborns (p = 0.04). At the allowed 42-day storage limit, projected mean neonatal PTR24 was 95.9%; for adults, it was 83.8% (p = 0.0002). CONCLUSIONS: These data provide evidence that storage duration of allogeneic RBCs intended for neonates can be increased without affecting PTR24 . This conclusion supports the practice of transfusing RBCs stored up to 42 days for small-volume neonatal transfusions to limit donor exposure.

Development, validation, and potential applications of biotinylated red blood cells for posttransfusion kinetics and other physiological studies: evidenced-based analysis and recommendations.

The current reference method in the United States for measuring in vivo population red blood cell (RBC) kinetics utilizes chromium-51 (51 Cr) RBC labeling for determining RBC volume, 24-hour posttransfusion RBC recovery, and long-term RBC survival. Here we provide evidence supporting adoption of a method for kinetics that uses the biotin-labeled RBCs (BioRBCs) as a superior, versatile method for both regulatory and investigational purposes. RBC kinetic analysis using BioRBCs has important methodologic, analytical, and safety advantages over 51 Cr-labeled RBCs. We critically review recent advances in labeling human RBCs at multiple and progressively lower biotin label densities for concurrent, accurate, and sensitive determination of both autologous and allogeneic RBC population kinetics. BioRBC methods valid for RBC kinetic studies, including successful variations used by the authors, are presented along with pharmacokinetic modeling approaches for the accurate determination of RBC pharmacokinetic variables in health and disease. The advantages and limitations of the BioRBC method-including its capability of determining multiple BioRBC densities simultaneously in the same individual throughout the entire RBC life span-are presented and compared with the 51 Cr method. Finally, potential applications and limitations of kinetic BioRBC determinations are discussed.

Efficacy of transfusion with granulocytes from G-CSF/dexamethasone-treated donors in neutropenic patients with infection.

High-dose granulocyte transfusion therapy has been available for 20 years, yet its clinical efficacy has never been conclusively demonstrated. We report here the results of RING (Resolving Infection in Neutropenia with Granulocytes), a multicenter randomized controlled trial designed to address this question. Eligible subjects were those with neutropenia (absolute neutrophil count <500/µL) and proven/probable/presumed infection. Subjects were randomized to receive either (1) standard antimicrobial therapy or (2) standard antimicrobial therapy plus daily granulocyte transfusions from donors stimulated with granulocyte colony-stimulating factor (G-CSF) and dexamethasone. The primary end point was a composite of survival plus microbial response, at 42 days after randomization. Microbial response was determined by a blinded adjudication panel. Fifty-six subjects were randomized to the granulocyte arm and 58 to the control arm. Transfused subjects received a median of 5 transfusions. Mean transfusion dose was 54.9 × 10(9) granulocytes. Overall success rates were 42% and 43% for the granulocyte and control groups, respectively (P > .99), and 49% and 41%, respectively, for subjects who received their assigned treatments (P = .64). Success rates for granulocyte and control arms did not differ within any infection type. In a post hoc analysis, subjects who received an average dose per transfusion of ≥0.6 × 10(9) granulocytes per kilogram tended to have better outcomes than those receiving a lower dose. In conclusion, there was no overall effect of granulocyte transfusion on the primary outcome, but because enrollment was half that planned, power to detect a true beneficial effect was low. RING was registered at www.clinicaltrials.gov as #NCT00627393.

Antibodies to biotinylated red blood cells in adults and infants: improved detection, partial characterization, and dependence on red blood cell-biotin dose.

BACKGROUND: Biotin-labeled red blood cells (BioRBCs) are used for in vivo kinetic studies. Because BioRBC dosing occasionally induces antibodies, a sensitive and specific anti-BioRBC detection assay is needed. STUDY DESIGN AND METHODS: Aims were to 1) develop a gel card assay to evaluate existing, naturally occurring and BioRBC-induced plasma antibodies, 2) compare gel card and tube agglutination detection results, and 3) test for a relationship of antibody induction and BioRBC dose. Reagent BioRBCs were prepared using sulfo-NHS biotin ranging from densities 18 (BioRBC-18) to 1458 (BioRBC-1458) µg/mL RBCs. RESULTS: Among BioRBC-exposed subjects, gel card and tube agglutination results were concordant in 21 of 22 adults and all 19 infant plasma samples. Gel card antibody detection sensitivity was more than 10-fold greater than tube agglutination. Twelve to 16 weeks after BioRBC exposure, induced anti-antibodies were detected by gel card in three of 26 adults (12%) at reagent densities BioRBC-256 or less, but in none of 41 infants. Importantly, induced anti-BioRBC antibodies were associated with higher BioRBC dose (p = 0.008); no antibodies were detected in 18 subjects who received BioRBC doses less than or equal to BioRBC-18. For noninduced BioRBC antibodies, six of 1125 naïve adults (0.3%) and none of 46 naïve infants demonstrated existing anti-BioRBC antibodies using reagent BioRBC-140 or -162. Existing anti-BioRBCs were all neutralized by biotin compounds, while induced antibodies were not. CONCLUSIONS: The gel card assay is more sensitive than the tube agglutination assay. We recommend reagent BioRBC-256 for identifying anti-BioRBCs. Use of a low total RBC biotin label dose (≤ BioRBC-18) may minimize antibody induction.

Clinical outcomes in a cohort of patients with heparin-induced thrombocytopenia.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a thrombotic disorder usually prompting treatment with non-heparin anticoagulants. The benefits and risks of such treatments have not been fully assessed. METHODS: We analyzed data for 442 patients having a positive heparin-platelet factor 4 antibody test and recent heparin exposure. The primary outcome was a composite endpoint (death, limb amputation/gangrene, or new thrombosis). Secondary outcomes included bleeding and the effect of anticoagulation. FINDINGS: Seventy-one patients (16%) had HIT with thrombosis (HIT-T); 284 (64%) had HIT without thrombosis (isolated HIT); 87 (20%) did not have HIT. An intermediate or high "4T" score was found in 85%, 58%, and 8% of the three respective groups. Non-heparin anticoagulation was begun in 80%, 56%, and 45%. The composite endpoint occurred in 48%, 36%, and 17% (P = .01) of which 61%, 38%, and 40% were receiving non-heparin anticoagulation. Compared with the no HIT group, the composite endpoint was significantly more likely in HIT-T [HR 2.48 (1.35-4.55), P = .003)] and marginally more likely in isolated HIT [HR 1.66 (0.96-2.85), P = .071]. Importantly, risk increased (HR 1.77, P = .02) after platelet transfusion. Major bleeding occurred in 48%, 36%, and 16% of the three groups (P = .005). Non-heparin anticoagulation was not associated with a reduction in composite endpoint events in either HIT group. INTERPRETATION: HIT patients have high risks of death, limb amputation/gangrene, thrombosis, and bleeding. Non-heparin anticoagulant treatment may not benefit all patients and should be considered only after careful assessment of the relative risks of thrombosis and bleeding in individual patients.

Incidence of transfusion reactions: a multicenter study utilizing systematic active surveillance and expert adjudication.

BACKGROUND: Prevalence estimates of the serious hazards of transfusion vary widely. We hypothesized that the current reporting infrastructure in the United States fails to capture many transfusion reactions and undertook a multicenter study using active surveillance, data review, and adjudication to test this hypothesis. STUDY DESIGN AND METHODS: A retrospective record review was completed for a random sample of 17% of all inpatient transfusion episodes over 6 months at four academic tertiary care hospitals, with an episode defined as all blood products released to a patient in 6 hours. Data were recorded by trained clinical research nurses, and serious reactions were adjudicated by a panel of transfusion medicine experts. RESULTS: Of 4857 transfusion episodes investigated, 1.1% were associated with a serious reaction. Transfusion-associated circulatory overload was the most frequent serious reaction noted, being identified in 1% of transfusion episodes. Despite clinical notes describing a potential transfusion association in 59% of these cases, only 5.1% were reported to the transfusion service. Suspected transfusion-related acute lung injury/possible transfusion-related acute lung injury, anaphylactic, and hypotensive reactions were noted in 0.08, 0.02, and 0.02% of transfusion episodes, respectively. Minor reactions, including febrile nonhemolytic and allergic, were noted in 0.62 and 0.29% of transfusion episodes, respectively, with 30 and 50% reported to the transfusion service. CONCLUSION: Underreporting of cardiopulmonary transfusion reactions is striking among academic, tertiary care hospitals. Complete and accurate reporting is essential to identify, define, establish pathogenesis, and mitigate/treat transfusion reactions. A better understanding of the failure to report may improve the accuracy of passive reporting systems.

Neutrophil/granulocyte transfusions collected from G-CSF + dexamethasone-stimulated donors.

PURPOSE OF REVIEW: The purpose of this review is to report a recently completed multicenter randomized controlled trial of neutrophil/granulocyte transfusions collected from G-CSF + dexamethasone donors to treat neutropenic infections in oncology and transplant patients, within the context of other historic and current clinical trials.The multicenter trial (RING Study) was funded by the NHLBI transfusion medicine/hemostasis clinical trials network. RECENT FINDINGS: There was no significant benefit of therapeutic neutrophil/granulocyte transfusions versus antibiotics per intention to treat analysis, but 32% of patients received substandard neutrophil doses. Separate analysis suggested patients given a higher neutrophil doses had better outcomes. SUMMARY: Efficacy of 'high-dose' therapeutic neutrophil/granulocyte transfusions remains unproven, but promising.

Autologous Infant and Allogeneic Adult Red Cells Demonstrate Similar Concurrent Post-Transfusion Survival in Very Low Birth Weight Neonates.

OBJECTIVE: Based on the hypothesis that neonatal autologous red blood cell (RBC) survival (RCS) is substantially shorter than adult RBC, we concurrently tracked the survival of transfused biotin-labeled autologous neonatal and allogeneic adult RBC into ventilated, very low birth weight infants. STUDY DESIGN: RBC aliquots from the first clinically ordered, allogeneic adult RBC transfusion and from autologous infant blood were labeled at separate biotin densities (biotin-labeled RBC [BioRBC]) and transfused. Survival of these BioRBCs populations were concurrently followed over weeks by flow cytometric enumeration using leftover blood. Relative tracking of infant autologous and adult allogeneic BioRBC was analyzed by linear mixed modeling of batched weekly data. When possible, Kidd antigen (Jka and Jkb) mismatches between infant and donor RBCs were also used to track these 2 populations. RESULTS: Contrary to our hypothesis, concurrent tracking curves of RCS of neonatal and adult BioRBC in 15 study infants did not differ until week 7, after which neonatal RCS became shortened to 59%-79% of adult enumeration values for uncertain reasons. Analysis of mismatched Kidd antigen RBC showed similar results, thus, confirming that BioRBC tracking is not perturbed by biotin RBC labeling. CONCLUSIONS: This study illustrates the utility of multidensity BioRBC labeling for concurrent measurement of RCS of multiple RBC populations in vivo. The similar RCS results observed for neonatal and adult BioRBCs transfused into very low birth weight infants provides strong evidence that the circulatory environment of the newborn infant, not intrinsic infant-adult RBC differences, is the primary determinant of erythrocyte survival. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00731588.

Transfusion-related adverse events in the Platelet Dose study.

BACKGROUND: How platelet (PLT) product characteristics such as dose, source (whole blood derived [WBD] vs. apheresis), storage duration, and ABO matching status affect the risks of transfusion-related adverse events (TRAEs) is unclear. Similarly, more information is needed to define how recipient characteristics affect the frequency of TRAEs after PLT transfusion. STUDY DESIGN AND METHODS: In the multicenter Platelet Dose ("PLADO") study, pediatric and adult hematology-oncology patients with hypoproliferative thrombocytopenia were randomized to receive low-dose (LD), medium-dose (MD), or high-dose (HD) PLT prophylaxis for a pretransfusion PLT count of not more than 10 × 10(9) /L. All PLT units (apheresis or WBD) were leukoreduced. Post hoc analyses of PLADO data were performed using multipredictor models. RESULTS: A total of 5034 PLT transfusions to 1102 patients were analyzed. A TRAE occurred with 501 PLT transfusions (10.0%). The most common TRAEs were fever (6.6% of transfusions), allergic or hypersensitivity reactions (1.9%), and sinus tachycardia (1.8%). Patients assigned HD PLTs were more likely than LD or MD patients to experience any TRAE (odds ratio for HD vs. MD, 1.50; 95% confidence interval, 1.10-2.05; three-group comparison p = 0.02). PLT source and ABO matching status were not significantly related to overall TRAE risk. Compared to a patient's first PLT transfusion, subsequent PLT transfusions were less likely to have a TRAE reported, primarily due to a lower risk of allergic or hypersensitivity reactions. CONCLUSION: The most important PLT unit characteristic associated with TRAEs was PLT dose per transfusion. HD PLTs may increase the risk of TRAEs, and LD PLTs may reduce the risk.

The impact of platelet transfusion characteristics on posttransfusion platelet increments and clinical bleeding in patients with hypoproliferative thrombocytopenia.

Platelet characteristics, such as platelet dose, platelet source (apheresis vs pooled), platelet donor-recipient ABO compatibility, and duration of platelet storage, can affect posttransfusion platelet increments, but it is unclear whether these factors impact platelet transfusion efficacy on clinical bleeding. We performed secondary analyses of platelet transfusions given in the prospective randomized Platelet Dose Study, which included 1272 platelet-transfused hematology-oncology patients who received 6031 prophylactic platelet transfusions. The primary outcome of these analyses was time from first transfusion to first World Health Organization ≥ grade 2 bleeding. Platelet transfusion increments were assessed at 0.25 to 4 hours and 16 to 32 hours after platelet transfusion. There were 778 patients evaluable for analysis of time to bleeding. Adjusted models showed that randomized dose strategy, platelet source, ABO compatibility, and duration of storage did not predict this outcome. Platelet increments were generally higher for transfusions of apheresis platelets, ABO-identical platelets, and platelets stored 3 days versus 4 to 5 days. Thus, although platelet source, ABO compatibility, and duration of storage exert a modest impact on both absolute and corrected posttransfusion platelet increments, they have no measurable impact on prevention of clinical bleeding. This trial was registered at www.clinicaltrials.gov as #NCT00128713.

Bleeding risks are higher in children versus adults given prophylactic platelet transfusions for treatment-induced hypoproliferative thrombocytopenia.

Age-group analyses were conducted of patients in the prophylactic platelet dose trial (PLADO), which evaluated the relation between platelet dose per transfusion and bleeding. Hospitalized patients with treatment-induced hypoproliferative thrombocytopenia were randomly assigned to 1 of 3 platelet doses: 1.1 × 10(11), 2.2 × 10(11), or 4.4 × 10(11) platelets/m(2) per transfusion, given for morning counts of ≤ 10 000 platelets/µL. Daily hemostatic assessments were performed. The primary end point (percentage of patients who developed grade 2 or higher World Health Organization bleeding) was evaluated in 198 children (0-18 years) and 1044 adults. Although platelet dose did not predict bleeding for any age group, children overall had a significantly higher risk of grade 2 or higher bleeding than adults (86%, 88%, 77% vs 67% of patients aged 0-5 years, 6-12 years, 13-18 years, vs adults, respectively) and more days with grade 2 or higher bleeding (median, 3 days in each pediatric group vs 1 day in adults; P < .001). The effect of age on bleeding differed by disease treatment category and was most pronounced among autologous transplant recipients. Pediatric subjects were at higher risk of bleeding over a wide range of platelet counts, indicating that their excess bleeding risk may be because of factors other than platelet counts.

Dose of prophylactic platelet transfusions and prevention of hemorrhage.

BACKGROUND: We conducted a trial of prophylactic platelet transfusions to evaluate the effect of platelet dose on bleeding in patients with hypoproliferative thrombocytopenia. METHODS: We randomly assigned hospitalized patients undergoing hematopoietic stem-cell transplantation or chemotherapy for hematologic cancers or solid tumors to receive prophylactic platelet transfusions at a low dose, a medium dose, or a high dose (1.1x10(11), 2.2x10(11), or 4.4x10(11) platelets per square meter of body-surface area, respectively), when morning platelet counts were 10,000 per cubic millimeter or lower. Clinical signs of bleeding were assessed daily. The primary end point was bleeding of grade 2 or higher (as defined on the basis of World Health Organization criteria). RESULTS: In the 1272 patients who received at least one platelet transfusion, the primary end point was observed in 71%, 69%, and 70% of the patients in the low-dose group, the medium-dose group, and the high-dose group, respectively (differences were not significant). The incidences of higher grades of bleeding, and other adverse events, were similar among the three groups. The median number of platelets transfused was significantly lower in the low-dose group (9.25x10(11)) than in the medium-dose group (11.25x10(11)) or the high-dose group (19.63x10(11)) (P=0.002 for low vs. medium, P<0.001 for high vs. low and high vs. medium), but the median number of platelet transfusions given was significantly higher in the low-dose group (five, vs. three in the medium-dose and three in the high-dose group; P<0.001 for low vs. medium and low vs. high). Bleeding occurred on 25% of the study days on which morning platelet counts were 5000 per cubic millimeter or lower, as compared with 17% of study days on which platelet counts were 6000 to 80,000 per cubic millimeter (P<0.001). CONCLUSIONS: Low doses of platelets administered as a prophylactic transfusion led to a decreased number of platelets transfused per patient but an increased number of transfusions given. At doses between 1.1x10(11) and 4.4x10(11) platelets per square meter, the number of platelets in the prophylactic transfusion had no effect on the incidence of bleeding. (ClinicalTrials.gov number, NCT00128713.)