Leukocyte depletion for safe blood transfusion

Production and stability of cultured red blood cells depends on the concentration of cholesterol in culture medium

The production of cultured red blood cells (cRBC) for transfusion purposes requires large scale cultures and downstream processes to purify enucleated cRBC. The membrane composition, and cholesterol content in particular, are important during proliferation of (pro)erythroblasts and for cRBC quality. Therefore, we tested the requirement for cholesterol in the culture medium during expansion and differentiation of erythroid cultures with respect to proliferation, enucleation and purification by filtration. The low cholesterol level (22 µg/dl) in serum free medium was sufficient to expand (pro)erythroblast cultures. Addition of 2.0 or 5.0 mg/dL of free cholesterol at the start of differentiation induction inhibited enucleation compared to the default condition containing 3.3 mg/dl total cholesterol derived from the addition of Omniplasma to serum free medium. Addition of 5.0 mg/dl cholesterol at day 5 of differentiation did not affect the enucleation process but significantly increased recovery of enucleated cRBC following filtration over leukodepletion filters. The addition of cholesterol at day 5 increased the osmotic resistance of cRBC. In conclusion, cholesterol supplementation after the onset of enucleation improved the robustness of cRBC and increased the yield of enucleated cRBC in the purification process.

Evaluation of a New Method of Leukocyte Extractions from the Leukoreduction Filter

This study's purpose was to optimize the leukocyte extraction protocol and evaluate the efficacy of this new protocol. 12BioR blood filters were collected from Tehran Blood Transfusion Center. A twosyringe system and Multi-step rinsing were designed for cell extraction. The final purpose of this optimization was: (1) removed the residual RBCs, (2) reversed the leukocyte trapping process, and (3) remove the microparticles to obtain the high yield of target cells. Finally, Extracted cells were evaluated by Automated Cell count; Samples smear differential cell count, Trypan blue, and Annexin-PI staining. The results showed that on average 11.88 × 108 ± 3.32 leukocytes recovered after indirect washing and that the mean count of granulocytes, lymphocytes, and Monocyte in this sample was 5.24 ± 2.18 × 108, 5.57 ± 1.74 × 108, and 0.56 ± 0.38 × 108 respectively. Also, the mean percent of manual differential cell count after concentration was 42.81%, 41.80%, and 15.82% for granulocytes, lymphocytes, and monocytes respectively. Moreover, viability and apoptosis assay showed > 95% viability in mononuclear cells recovered from LRFs. It is concluded that the use of a double-syringe system and RBC and microparticles removal from leukoreduction filters lead to acceptable viable leukocyte count that can be used in in vitro and in vivo studies.

Comparative study of quality of leukoreduced packed red blood cell units as assessed by nageotte hemocytometry and flow cytometry

PURPOSE

Assessment of residual white blood cell (rWBC) count is vital to ascertain the quality of leukodepleted (LD) blood components. Automated cell analyzers lack the sensitivity for the assessment of very few leukocytes as found in LD blood components. Flow Cytometry (FC) based methods and Nageotte hemocytometer are the most commonly used techniques for this purpose. The objective of this study was to compare the use of Nageotte hemocytometer and FC for quality control of LD red blood cell units.

MATERIALS AND METHODS

A prospective, observational study was conducted in the Department of Immunohematology and Blood Transfusion of a tertiary care center from September 2018 to September 2020. About 303 LD-packed red blood cell units were tested by FC and Nageotte hemocytometer for rWBCs.

RESULTS

The number of rWBC (mean) detected by flow cytometer and Nageotte's hemocytometer was 1.06 ± 0.43 white blood cell (WBC)/μL and 0.67 ± 0.39 WBC/μL, respectively. Coefficient of variation was 58.37% by Nageotte hemocytometer method and 40.46% by FC. Linear regression analysis did not show any correlation (R2= 0.098, P = 0.001) whereas Pearson's correlation coefficient showed a weak relation (r = 0.31) between the two methods.

CONCLUSION

Flow cytometric technique provides a more precise and accurate objective tool compared to Nageotte hemocytometer which is labor intensive, time consuming, and prone to errors arising out of subjectivity along with reported underestimation bias. In the absence of adequate infrastructure, resources, and trained workforce, Nageotte hemocytometer method is a reliable alternative. Nageotte's chamber could be best used in the resource-constrained setup as it offers a relatively inexpensive, simple, and viable means to enumerate rWBCs.

Leukocyte reduction filters as an alternative source of peripheral blood leukocytes for research

INTRODUCTION

Peripheral blood leukocytes are a suitable cell model for science research. However, blood samples from healthy volunteers are limited in volume and difficult to obtain due to the complexity of volunteer recruitment.

OBJECTIVE

Therefore, it is urgent to find an alternative source of peripheral blood leukocytes.

METHOD

One of the possibilities is the use of leukocyte reduction filters (LRFs) in blood banks that is used for preparation of leukoreduced blood products. More than 90% of the leukocytes are trapped in the leukofilters allowing the desired blood product to pass through.

RESULTS

It has been reported that the biological function of leukocytes collected from the filters are no different from those isolated from buffy coats, leukapheresis products and whole blood (WB) cells. Moreover, LRFs are waste products that are discarded after leukoreduction.

CONCLUSION

Thus, leukofilters represent an economic source of human cell populations that can be used for a variety of investigative purposes, with no cost. In the present study, we reviewed the different usage of LRFs in the research, clinical and commercial applications.

Impact of Allogeneic Leukocyte-Depleted Red Blood Cell Transfusion on Inflammatory Response and Blood Coagulation in Patients with Recurrence of Colon Cancer after Operation

Objective

Anemia inevitably affects the survival of cancer patients. In clinical practice, patients with anemia and decreased blood volume are treated by component blood transfusion. Through targeted blood transfusion therapy, the efficacy of blood transfusion treatment can be validly improved, which renders clinical benefits in reducing transfusion-induced adverse reactions (ARs). This research project mainly investigated the impact of allogeneic leukocyte-depleted red blood cell (LDRBC) transfusion on inflammatory response and coagulation status of patients with postoperative recurrence of colon cancer (CC).

Methods

A total of 80 patients with postoperative recurrence of CC admitted to Changzhou Second People's Hospital affiliated to Nanjing Medical University from September 2017 to December 2020 were selected as the study subjects. 36 patients with allogeneic suspended red blood cell (RBC) transfusion were used as the control group (CG), and 44 patients receiving allogeneic LDRBC transfusion served as the observation group (OG). The two groups were compared regarding alterations in pretransfusion and posttransfusion serum inflammatory factors, stress indicators and coagulation function, incidence of ARs, postoperative infection, and average incision healing time.

Results

After blood transfusion, serum tumor necrosis interleukin- (IL-) 6, IL-10, factor-α (TNF-α), and C-reactive protein (CRP) decreased in both cohorts, with lower parameters in CG (P < 0.05); the stress indexes, adrenocortical hormone (ACTH), adrenaline (AD), norepinephrine (NE), and cortisol (Cor) increased, especially in CG (P < 0.05); prothrombin time (PT), thrombin time (TT), and activated partial prothrombin time (APTT) in CG were lower than those in OG, and FIB was higher than that in OG with significant differences between two cohorts (all P < 0.05). The two groups had similar cases of lung infection and wound infection (P > 0.05), but the incision healing time was evidently shorter in OG as compared to CG (9.73 ± 1.86 vs 14.67 ± 2.39 d, P < 0.05). The total incidence of ARs was 16.7% in CG and 6.9% in OG, with no significant difference (P > 0.05).

Conclusions

In the blood transfusion treatment for patients with postoperative recurrence of CC, LDRBC transfusion renders significant clinical benefits, which can effectively improve the coagulation function of patients, reduce stress reaction, and shorten incision healing time without increasing ARs during treatment and postoperative infection rate, which is worth popularizing.

Person-to-Person Cancer Transmission via Allogenic Blood Transfusion

Despite the recognized capability of Circulating Tumor Cells (CTCs) to seed tumors, allogenic blood transfusions are not presently screened for the presence of CTCs. Previous research has examined blood transfusions and the associated risk of cancer recurrence, but not cancer of unknown primary (CUP) occurrence. The Hypothesis explored in this paper proposes that there is potential for cancers to be transmitted from donor-to-patient via CTCs in either blood transfusions or organ transplants or both. This proposed haematogenic tumor transmission will be discussed in relation to two scenarios involving the introduction of donor-derived CTC's from allogeneic blood transfusions into either known cancer surgery patients or into non-cancer patients. The source of CTCs arises either from the donor with a 'clinically dormant cancer' or a 'pre-clinical cancer' existing as yet undiagnosed, in the donor. Given the significant number of allogenic blood transfusions that occur worldwide on a yearly basis, allogenic blood transfusions have the potential to expose a substantial number of non-cancer recipients to the transmission of CTCs and associated tumor risk. This risk is greatly amplified in the low-income nations where the blood collection and processing protocols, including exclusion and screening criteria are less stringent than those in high-income countries.

Enhancing the blood safety program in Myanmar: Report on projects of global extension of medical technologies of Japan

The National Center for Global Health and Medicine has long collaborated with the blood program in Myanmar, and the Center started a new project in 2015 to enhance blood transfusion safety as part of a new set of projects of global extension of medical technologies that aims to improve public health and medicine in developing countries under public-private partnerships. The project resulted in remarkable achievements, including maintaining a high proportion of voluntary blood donations despite a rapidly growing demand for blood, ensuring blood safety from the donor to the recipient, and creating public-private partnerships. The project supported the introduction of blood grouping using the tube method at hospital blood banks, safety measures during blood transfusions, and effective use of blood products including component blood. The project identified the need for medical devices such as leukocyte filters, serofuges, and refrigerators to store blood products. The success of the project may depend on mutual understanding and trust based on the duration of collaboration, improvement of the requirement for medical safety (including blood safety) in the country, and shifting the mindset of partner companies in public-private partnerships to create new demand by encouraging improvement of the quality of care and requiring the safety of medical care. In this era of sustainable development goals, the hopes are that these experiences will help other countries seeking to improve their public health through public-private partnerships.

Double-filtered leukoreduction as a method for risk reduction of transfusion-associated graft-versus-host disease

Background

Transfusion-associated graft-versus-host disease (TA-GvHD) is caused by leukocytes, specifically T cells within a transfused blood product. Currently, the prevention of transfusion-associated graft-versus-host disease is performed by irradiation of blood products. With a sufficient reduction of leukocytes, the risk for TA-GvHD can be decreased. With consistent advances in current state-of-the-art blood filters, we herein propose that double filtration can sufficiently reduce leukocytes to reduce the risk for TA-GvHD.

Materials

Thirty RBC concentrates were filtered with leukocyte filters, followed by storage at 1–6 ^oC for 72 hours, and then a second filtration was performed. Residual leukocytes in the double-filtered RBC units (n = 30) were assessed with flow cytometric methods, and an additional assay with isolated peripheral blood mononuclear cells (PBMCs) (n = 6) was done by both flow cytometric methods and an automated hematology analyzer. Quality of the RBCs after filtration was evaluated by hematological and biochemical tests. In vitro T cell expansion was performed using anti-CD3/CD28-coated Dynabeads or anti-CD3 (OKT3). In vivo experiment for GvHD was performed by using NOD.Cg-Prkdc^scid Il2rg^tm1Wjl/SzJ (NSG) mice.

Results

Double-filtered blood products showed residual leukocyte levels below detection limits, which calculated to be below 1200–2500 cells per blood unit. In vitro expansion rate of T cells showed that 6x10³ and 1x10³ cell-seeded specimens showed 60.8±10.6 fold and 10.2±9.7-fold expansion, respectively. Cell expansion was not sufficiently observed in wells planted with 1x10² or 10 cells. In vivo experiments showed that mice injected with 1x10⁵ or more cells cause fatal GvHD. GvHD induced inflammation was observed in mice injected with 1x10⁴ or more cells. No evidence of GvHD was found in mice injected with 10³ cells.

Conclusions

Our study suggests that additional removal of contaminating lymphocytes by a second leukodepletion step may further reduce the risk for TA-GvHD.

Efficiency of leukocyte depletion filters and micro-aggregate filters following intra-operative cell salvage during cesarean delivery

BACKGROUND

Intra-operative cell salvage is not routinely used during cesarean delivery because it is not cost-effective for patients at low risk of hemorrhage and there are theoretical concerns about amniotic fluid embolism. Some guidelines recommend using leukocyte depletion filters to decrease the risk of amniotic fluid embolism before re-infusing salvaged blood, but these filters are not available in Japan. We compared the efficacy and safety of leukocyte depletion and micro-aggregate filters in combination with intra-operative cell salvage during cesarean delivery.

METHODS

Blood was collected in a Cell Saver 5 reservoir during cesarean delivery. Four samples were collected: pre-wash, post-wash, post-filtration with a leukocyte depletion filter and post-filtration with a micro-aggregate filter. Each sample was analyzed for amniotic fluid markers of zinc coproporphyrin-1 and sialyl-Tn, for fetal hemoglobin, and the sample underwent pathological examination for white blood cells and squamous cells. Post-filtration samples were compared using paired t-tests with P <0.05 indicating statistical significance.

RESULTS

Zinc coproporphyrin-1 and sialyl-Tn were negative at almost all sample points. Squamous cells decreased by 59.1% post-wash and 91.2% post-filtration using a leukocyte depletion filter. Leukocyte depletion filters removed 99.7% of white blood cells and were more effective in removing white blood cells than micro-aggregate filters (P=0.02).

CONCLUSION

Leucocyte depletion filters are more effective in removing white blood cells and squamous cells than micro-aggregate filters, and their introduction for intra-operative cell salvage during cesarean delivery should be considered in Japanese clinical practice.

Perioperative blood transfusion has no effect on overall survival after esophageal resection for esophageal squamous cell carcinoma: A retrospective cohort study

BACKGROUND

The impact of perioperative blood transfusion (PBT) on the prognosis of esophageal cancer patients remains inconclusive. The purpose of this study was to assess the association between PBT and survival in esophageal squamous cell carcinoma (ESCC) patients.

MATERIALS AND METHODS

In this retrospective study, patients with ESCC who underwent esophageal resection from January 2008 to December 2011 were analyzed. The overall survival and postoperative outcomes between PBT and non-PBT patients were compared using Cox regression and propensity score matching (PSM) analysis.

RESULTS

A total of 935 patients were enrolled in this study. Before PSM, the 5-year overall survival rates in PBT and non-PBT patients were 48.4% and 56.3% (P = 0.001), respectively. The postoperative infection rate in PBT patients was 32.32%, which exceeded the rate of 24.22% in non-PBT patients (P = 0.008). PSM created 306 pairs of patients. After PSM, the 5-year overall survival rates in PBT and non-PBT patients were 49.4% and 51.0% (P = 0.334), respectively. The postoperative infection rate in PBT patients was 31.04%, which was higher than the rate of 26.47% in non-PBT patients (P = 0.105). Multivariable Cox regression analyses showed that PBT was not an independent risk factor for overall survival (HR: 0.792, 95% CI: 0.615-1.021, P = 0.072).

CONCLUSION

Perioperative blood transfusion has no effect on the overall survival of ESCC patients.

Transfusion-associated adverse reactions (TAARs) and cytokine accumulations in the stored blood components: the impact of prestorage versus poststorage leukoreduction

Leukoreduction in blood units could prevent patients undergoing transfusions from transfusion-associated adverse reactions (TAARs) such as febrile nonhemolytic transfusion reactions (FNHTRs). However, the effect of prestorage and poststorage leukoreduction on TAARs and its underlying mechanisms in stored blood components remains to be determined. Therefore, we investigated the impact of prestorage leukocyte-reduced (pre-LR) and poststorage leukocyte-reduced (post-LR) blood products, including red blood cells (RBCs) and apheresis platelets (PHs), on the incidence of FNHTRs and other TAARs in patients who received transfusions from 2009 to 2014 in a tertiary care center. We also investigated the difference of leukocyte-related bioactive mediators between pre- and post-LR blood components. The results indicated that prevalence of TAARs was significantly reduced in the transfusions of pre-LR blood components. Particularly, the prevalence of FNHTRs was significantly reduced in the pre-LR RBC transfusions and the prevalence of allergy reactions was markedly reduced in the pre-LR PH transfusions. Furthermore, in vitro evaluation of cytokines in the pre- and post-LR blood components revealed that IL-1β, IL-8 and RANTES levels were significantly elevated in the post-LR RBCs during the storage. In contrast, IL-1β, IL-6 and IL-8 levels were significantly elevated in the post-LR PHs during the storage. These findings suggested that prestorage leukoreduction had a diminishing effect on the development of TAARs, which could be associated with less accumulation of cytokines in the stored blood components.

Quality Assessment of Platelet-Rich Fibrin-Like Matrix Prepared from Whole Blood Samples after Extended Storage

The platelet-rich fibrin–like matrix (PRFM) is usually prepared onsite and immediately used for regenerative therapy. Nonetheless, to meet the clinical necessity of preserving the PRFM without quality deterioration, we developed a method for preparation of PRFMs from short-term-stored whole blood (WB) samples. In this study, to evaluate the practical expiration date of storage, we extended the storage time of WB samples from 2 to 7 days and assessed the quality of the resulting PRFMs. WB samples collected with acid-citrate-dextrose were stored with gentle agitation at ambient temperature. To prepare PRFMs, the stored WB samples were mixed with CaCl₂ in glass tubes and centrifuged. Fibrin fiber networks, CD41 and CD62P expression, and Platelet Derived Growth Factor-BB (PDGF-BB) levels were examined by scanning electron microscopy (SEM), flow cytometry, and an Enzyme-Linked ImmunoSorbent Assay (ELISA), respectively. Long-term storage had no significant effect on either blood cell counts or platelet functions tested. The resulting PRFMs were visually identical to freshly prepared ones. PDGF-BB levels did not markedly decrease in a time-dependent manner. However, fibrin fibers gradually became thinner after storage. Although the coagulation activity may diminish, we propose that PRFMs can be prepared—without evident loss of quality—from WB samples stored for up to 7 days by our previously developed method.

Reduced Blood Cell Adhesion on Polypropylene Substrates through a Simple Surface Zwitterionization

To overcome the thrombogenic reactions of hydrocarbon-based biomaterials in clinical blood treatment, we introduce a model study of surface zwitterionization of a polypropylene (PP) substrate using a set of well-defined copolymers for controlling the adhesion of blood cells in vitro. Random and block copolymers containing zwitterionic units of 2-methacryloyloxyethyl phosphorylcholine (MPC), [3-(methacryloylamino)propyl]dimethyl(3-sulfopropyl)ammonium hydroxide inner salt (SBAA), or nonionic units of 2-hydroxyethyl methacrylate (HEMA) with a controlled hydrophobic segment of 70% n-butyl methacrylate (BMA) units in these polymers were synthesized through reversible addition-fragmentation chain transfer polymerization. A systematic study of how zwitterionic and nonionic copolymer architectures associated with controlled chain orientation via hydration processes affect blood compatibility is reported. The surface wettability of PP substrates coated with the block copolymer with poly(MPC) (PMPC) segments was higher than that of the random copolymer poly(MPC-random-BMA). However, only the random copolymers with SBAA units demonstrate a higher surface wettability. The PP substrate coated with nonionic copolymers containing HEMA units showed relatively lower hydration capability associated with higher protein adsorption, platelet adhesion, and leukocyte attachment than those with zwitterionic copolymers. The random copolymer poly(SBAA-random-BMA) coated on the PP substrates exhibited resistance to cell adhesion in human whole blood at a level comparable to that of MPC copolymers. An ideal zwitterionic PP substrate could be obtained by coating it with a block copolymer composed of PMPC and poly(BMA) (PBMA) segments, PMPC-block-PBMA. The water contact angle decreased dramatically from approximately 100° on the original PP substrate to 11° within 30 s. The number of blood cells attached on PMPC-block-PBMA decreased significantly to less than 2.5% of that on original PP. These results prove that the rational design of zwitterionic polymers incorporated with a hydrophobic anchoring portion provides a promising approach to reduce blood cell adhesion and protein adsorption of hydrocarbon-based biomaterials applied in direct contact with human whole blood.

Biochemical and cellular changes in leukocyte-depleted red blood cells stored for transfusion

BACKGROUND

To evaluate biochemical and cellular changes associated with the storage of leukocyte-depleted red blood cells (RBCs).

METHODS

We investigated 10 leukocyte-depleted RBC units, randomly chosen from volunteer donors. Every week an aliquot was collected for laboratorial evaluation, which included complete cell blood count, glucose-6-phosphate dehydrogenase (G6PD) activity, extracellular sodium, potassium and pH, membrane-bound hemoglobin (MBH), band 3 profile, and quantification of RBC membrane proteins composition.

RESULTS

We observed an increase in mean cell volume (from 91.86 ± 4.65 fl to 98.10 ± 5.80 fl, day 0 vs. day 21; p < 0.05), red cell distribution width, percentage of macrocytic RBCs, reticulocyte hemoglobin content and a decreased percentage of microcytic RBCs, mean cell volume concentration and G6PD activity. The extracellular concentration of sodium decreased, and that of potassium increased significantly over time. RBC membrane composition revealed an increase in spectrin/ankyrin ratio after 21 days (from 4.84 ± 0.99 to 5.27 ± 0.94, day 0 vs. day 21; p < 0.05). At day 35, a decrease in ankyrin (from 6.44 ± 1.70% to 5.49 ± 1.96%, day 0 vs. day 35; p < 0.05), in protein 4.1/band 3, protein 4.2/band 3, and ankyrin/band 3 ratios and in band 5 was observed.

CONCLUSIONS

Our data show that leukocyte-depleted RBCs present changes in the RBC morphology, membrane protein composition, enzymatic activity, and extracellular electrolyte concentration and pH.

Microparticle profile and procoagulant activity of fresh-frozen plasma is affected by whole blood leukoreduction rather than 24-hour room temperature hold

BACKGROUND

Microparticles (MPs) are small phospholipid-containing vesicles that have procoagulant properties. MPs are thought to contribute to the hemostatic potential of plasma. This study investigated the effects of whole blood (WB) hold time and leukoreduction (LR) on the MP profile and hemostatic potential of fresh-frozen plasma (FFP).

STUDY DESIGN AND METHODS

WB units (n=12) from healthy donors were divided into two pairs and each pair was held at 20 to 24°C for 6 or 24 hours. At the designated hold time, 1 unit from the pair was LR while the other unit was not LR. FFP was prepared by standard procedures, aliquoted, and frozen. The MP content was determined by flow cytometry using an absolute count assay and specific labels for red blood cells (CD235a), platelets (CD41), and phosphatidylserine (PS). The hemostatic potential was determined by thrombelastography (TEG) and coagulation factor assays.

RESULTS

Compared to non-LR-FFP, LR-FFP had significantly lower numbers of MPs, particularly CD41+ MPs and PS-positive MPs (p<0.03). LR-FFP, compared to non-LR-FFP, had a slower clot formation time (p=0.002); lower clot strength (p<0.001); and lower Factor (F)VIII, FXII, and fibrinogen levels (p<0.01). With longer WB hold time, the TEG profile was unchanged, although FVIII levels were decreased as expected (p<0.01). On average FFP units met quality requirements.

CONCLUSION

LR of WB resulted in lower hemostatic potential of FFP in conjunction with depletion of MPs and coagulation factors. Longer WB hold time did not significantly affect the hemostatic potential of FFP as measured by TEG. Acceptable hemostatic quality was maintained for all FFP processing conditions studied.

Effects of non-leukocyte-reduced and leukocyte-reduced packed red blood cell transfusions on oxygenation of rat spinotrapezius muscle

Leukoreduction of blood used for transfusion alleviates febrile transfusion reactions, graft versus host disease and alloimmunization to leukocyte antigen. However, the actual clinical benefit of leukoreduction in terms of microcirculatory tissue O2 delivery after packed red blood cell (pRBC) transfusion has not been investigated. As such, the aim of this study was to determine the effects of non-leukoreduced (NLR) and leukoreduced (LR) fresh pRBC transfusion on interstitial oxygenation in anesthetized male Sprague-Dawley rats. Interstitial fluid PO2 and arteriolar diameters in spinotrapezius muscle preparations were monitored before and after transfusion with NLR- or LR-pRBCs. The major findings were that (1) transfusion of NLR-pRBCs significantly decreased interstitial oxygenation whereas transfusion of LR-pRBCs did not, and (2) transfusion with LR-pRBCs elicited a substantially greater increase in arterial blood pressure (ABP) than did transfusion with NLR-pRBCs. These changes in PO2 and ABP were not associated with changes in the diameters of resistance arterioles in the spinotrapezius muscle. These data suggest that transfusion of fresh NLR-pRBCs may negatively affect tissue oxygenation via enhanced leukocyte influx and decreased O2 delivery. They also suggest that leukocytes diminish the capability of transfused pRBCs to increase cardiac output. As such, transfusion of LR-pRBCs may be less deleterious on tissue PO2 levels than NLR-pRBCs although a concomitantly greater increase in ABP may accompany transfusion of LR-pRBCs.

The effect of pre-storage whole-blood leukocyte reduction on cytokines/chemokines levels in autologous CPDA-1 whole blood

BACKGROUND

In this study, we aimed to investigate the effectiveness of pre-storage leukocyte filtration of autologous blood (AB), especially focusing on the cytokines/chemokines accumulation on blood products.

MATERIALS AND METHODS

After approval of the ethics committee of the University of Tokyo, a total of 26 orthopedic patients, who donated AB prior to surgery after informed consent, were enrolled. The effects of filtration on blood cell counts were analyzed, and the accumulation of cytokines and chemokines were measured on pre- and post-leukoreduced (LR) samples, using the Luminex system. The time-dependent changes of the cytokines/chemokines and the effect of the filtration on their concentration were analyzed, and compared with the normal plasma levels reported in the literature.

RESULTS

LR effectively reduced the number of leukocytes and platelets, without affecting that of red cells. The concentration of most of the cytokines/chemokines analyzed, except the EGF, sCD40-L and sFas-L, decreased time-dependently of storage or did not change in pre-LR samples. However, EGF, sCD40L and sFas-L were significantly reduced by LR. Some, such as IL-8 and RANTES, were also importantly decreased by LR, and others, such as IL-1β and TNF-α, were not significantly affected by LR.

CONCLUSIONS

Leukocyte filtration effectively removes platelets and leukocytes from AB, thus preventing the accumulation of cytokines/chemokines. Since adverse effects due to AB transfusion, although rare, are observed, there is need to consider the implementation of pre-storage leukocyte reduction (PSLR) for AB.

Lack of effect of unrefrigerated young whole blood transfusion on patient outcomes after massive transfusion in a civilian setting

BACKGROUND

Warm fresh whole blood has been advocated for critical bleeding in the military setting. This study assessed whether unrefrigerated young whole blood transfusion, from donation to transfusion less than 24 hours, could reduce mortality of patients with critical bleeding in a civilian setting.

STUDY DESIGN AND METHODS

A linked data cohort study was conducted on a total of 353 consecutive patients requiring massive transfusion, defined as 10 units or more of red blood cells or whole blood transfusion within 24 hours, in a quaternary health care center in Australia.

RESULTS

Of the 353 patients with massive blood transfusion in the study, 77 received unrefrigerated young whole blood transfusion (mean, 4.0 units; interquartile range, 2-6). The diagnosis, severity of acute illness, age, sex, and ABO blood group were not significantly different between the patients who received unrefrigerated young whole blood and those who did not. Unrefrigerated young whole blood transfusions were associated with a slightly improved coagulation profile (lowest fibrinogen concentrations 1.7g/L vs. 1.4g/L, p=0.006; worst international normalization ratio, 2.4 vs. 2.8, p=0.05) but did not reduce the total utilization of allogeneic blood products and subsequent use of recombinant Factor VIIa (27% vs. 22%, p=0.358). Thirty-day mortality and 8-year survival after hospital discharge (hazard ratio, 1.05; 95% confidence interval, 0.41-2.65; p=0.93) were also not different after the use of unrefrigerated young whole blood transfusion.

CONCLUSIONS

Unrefrigerated young whole blood transfusion was not associated with a reduced mortality of patients requiring massive transfusion in a civilian setting when other blood products were readily available.