不同保存期的去白细胞悬浮红细胞上清液中微粒粒径分布研究

目的探索库存去白细胞悬浮红细胞(去白悬浮红)随着保存时间的延长,红细胞破损或溶血而产生的细胞碎片以及微粒变化,为输血安全提供启示性实验基础。方法取不同保存天数(3、7、14和21 d)的库存去白悬浮红进行上清液制备,应用动态光散射仪对样品中的各种微粒进行粒径分布分析。结果 3 d和7 d的库存去白悬浮红上清液样品中的微粒主要为10~25 nm微粒;从14 d开始,上清液样品中出现了更多150~300 nm的微粒,到21 d时,150~300 nm范围内的微粒占绝大部分。结论可通过测定库存红细胞制品上清液中微粒的粒径变化来评估红细胞的储存损伤程度,进一步探讨新的溶血评价方法。     

保存前滤除白细胞对预防FNHTR及改善红细胞变形能力的作用

目的探讨推广血站型滤器的应用效果。方法将悬浮红细胞分为过滤组和对照组,在保存前和保存期检测5种细胞因子的水平及红细胞变形指数（EI）;临床输血患者按所输去白细胞悬浮红细胞过滤前保存时间分为5组,分别为0d、≤7d、≤14d、≤21d和〉21d,观察各组FNHTR发生率。结果对照组细胞因子随保存时间的延长而在血液中不断积累,过滤组细胞因子在保存中维持在原有的较低水平;在保存后期过滤组EI明显高于对照组;FNHTR发生率与过滤前保存时间呈正相关（P〈0．01）。结论在悬浮红细胞保存中存在多种细胞因子的产生和累积,而去白细胞过滤可在一定程度上抑制这一效应;保存前滤除白细胞可以有效预防FNHTR的发生,故悬浮红细胞应在保存前滤除白细胞。     

去白细胞悬浮红细胞在保存期内生化指标的变化

目的探讨不同贮存时间库存去白细胞悬浮红细胞钾离子(K+)、钠离子(Na+)、氯离子(Cl-)、乳酸脱氢酶(LDH)、乳酸(LAC)及葡萄糖(GLU)的水平变化,以保证临床输血的安全、有效。方法将20名无偿献血者所献的各400 ml全血在24 h内制备成去白细胞悬浮红细胞,并将其均匀分装成5份,置于血液保存箱(4±2)℃直立保存。对分装剩余的去白细胞悬浮红细胞血液即刻检测,作为0 d数据;直立保存的5组血液分别在贮存的第7、14、21、28、35天时测定项目并记录结果。将直立保存的5组血液测得的数据分别与0 d测得的数据比较。结果K+、LAC含量随贮存时间的延长而显著增高,在贮存的第7、14、21、28、35天的含量显著高于第0天(P均<0.01),LDH在贮存的第14、21、28、35天的含量明显高于第0天(P均<0.01);Na+、GLU在贮存第14、21、28、35天的含量明显低于第0天(P均<0.01);Cl-的含量在贮存期内无明显变化。结论去白细胞悬浮红细胞随贮存时间的延长,部分生化指标呈现不同变化。在临床输血时应根据患者的情况选择不同贮存期的血液,提高血液输注的安全性和有效性。     

血液在不同保存期有形成份及理化指标变化的研究

目的 探讨血液在不同保存时间对其质量的影响,检测血液成分的变化,为临床输血提供科学依据。方法 将采集200ml CPDA-1抗凝全血100份作标记和编号,分别在0d、3d、7d、14d、21d、28d、35d进行各种有形成分和部分生化指标的检测。按卫生部《全国临床检验操作规程》的方法严格操作。结果血液在35天保存期内,红细胞(RBC)无显著变化,保存7天白细胞(WBX)中粒细胞明显下降,7天血小板(PLT)明显下降;血粘度14天开始显著增加;保存时间逐渐延长K 浓度逐渐增高,14天起显著增高,Na 21天显著减少,碱性磷酸酶21天显著减少,CO2浓度28天显著增高,其余酶类、葡萄糖、蛋白质、胆红素、尿素氮无显著变化。保存期内纤维蛋白原无显著变化,28天FVⅢ.C下降只有当天的30％;游离血红蛋白21天开始增高有显著性,红细胞渗透脆性变化不大。结论 全血在保存期内并不"全",临床上应根据不同的病因选择不同保存期血液,提倡成分输血,提高临床输血疗效,降低不良反应。     

洗涤红细胞中K~+变化的影响因素研究

目的研究用MAP保养液保存的去白悬浮红细胞制备洗涤红细胞,其保存期内K~+浓度及其他相关性指标的变化趋势,为临床合理输血提供依据。方法选取去白和不去白悬浮红细胞制备MAP洗涤红细胞,检测其在不同保存期的K~+和Na~+浓度、游离血红蛋白浓度、红细胞渗透脆性、白细胞去除率、红细胞回收率等指标。结果去白悬浮红细胞较未去白悬浮红细胞制备的洗涤红细胞K+浓度升高速度慢,洗涤红细胞在保存期内,Na~+浓度逐渐下降,游离血红蛋白浓度逐渐升高,红细胞渗透脆性逐渐加强。结论临床输血时根据患者的不同情况有针对性选择不同保质期的洗涤红细胞,特别是针对高钾血症和新生儿患者等可优先选择即时洗涤红细胞(24 h内),而对于预防血浆过敏及白细胞副反应等患者,可选用MAP保存洗涤红细胞。     

去白细胞悬浮红细胞与悬浮红细胞储存期内溶血率的比较

目的观察去白细胞悬浮红细胞和常规制备悬浮红细胞在储存期内的溶血率变化,评价储存前白细胞过滤对于红细胞溶血率的的影响。方法随机采集80袋200 mL全血,将其分为白细胞过滤组和未过滤组,其中过滤组分别用上海输血技术公司、威高和南格尔3家公司的血袋各采20袋,过滤并制成悬浮红细胞;未过滤组用上海输血技术公司普通血袋采20袋,制成悬浮红细胞。2组置于(4±2)℃条件下储存35 d,在储存期14、21、28、35 d取样检测红细胞溶血率。结果 60袋去白细胞悬浮红细胞储存期内平均红细胞溶血率分别为14 d(0.11±0.06)%、21 d(0.20±0.10)%、28 d(0.31±0.13)%、35 d(0.42±0.15)%,20袋未过滤组平均红细胞溶血率分别为14 d(0.07±0.08)%、21 d(0.10±0.06)%、28 d(0.15±0.09)%、35 d(0.22±0.11)%,过滤保存21 d后溶血率有显著升高(P<0.05),但2组结果均符合欧盟和AABB标准中对于储存期末红细胞溶血率的要求。3家公司血袋制备的去白细胞悬浮红细胞保存期末溶血率差异无统计学意义(P>0.05)。结论储存前白细胞滤除过程未对35 d储存期的红细胞溶血率产生明显影响,35 d储存期的红细胞符合欧盟标准和AABB标准。     

血站型去白细胞悬浮红细胞保存效期的研究

目的 观察血站型去白细胞悬浮红细胞(以下称“去白红细胞”),在不同的保存时间段内细胞活性和功能的变化,为确定去白红细胞的保存效期,提供数据和参考依据.方法 用一次性去白细胞四联血袋采集全血,按标准操作规程离心、分浆后,红细胞悬浮于MAP液中,并通过去白细胞滤器,制成去白红细胞.提取400 mL全血制备的去白红细胞21袋,每袋各留取样品管6管,置4℃冰箱保存.用未过滤的悬浮红细胞做对照.于采血后d1、d7、d14、d21、d28、d35,测2组红细胞ATP和2,3-DPG值,并做统计学分析.结果 去白红细胞与悬浮红细胞各对应天数的ATP含量相比,均无统计学差异.组内比较:2组细胞各自d1和d35比较,去白红检验值为2 454.17±217.98,1 275.52±126.86;悬浮红检验值为2 270.83±220.99,1 190.76±86.95 (P＜0.05).2组红细胞2,3-DPG含量,除d21外,其余各时间段比较均无差异.组内d1和d35比较,2组均无统计学差异.结论 去白红细胞在MAP液中保存至d35,其ATP含量(51.97％)与悬浮红细胞(52.44％)相似,均＜70％.2,3-DPG含量优于悬浮红细胞.综合考虑其脆性、形态和游离血红蛋白变化等结果,我们推荐去白红细胞保存效期为28 d.     

不同滤器制得的去白细胞悬浮红细胞在不同保存期的相关指标比较

目的探讨不同生产厂家滤器制得的去白细胞悬浮红细胞在不同保存时间时相关指标优劣。方法随机使用4个厂家带白细胞滤器的一次性采血袋采集200、300、400mL全血,然后分别制备为1U、1.5U及2U的去白细胞悬浮红细胞共240袋,分别按照不同规格保存于(4±2)℃储血专用冰箱。使用无菌接驳器分别取同一规格、不同厂家的保存期为0、7、14、21、28和35d的悬浮去白细胞悬浮红细胞标本共计240份,测定其血容量、血细胞比容、白细胞残留量、血浆游离血红蛋白(FHb)水平、血红蛋白水平、并计算其储存期末溶血率。结果同一厂家滤器制备不同规格悬浮去白细胞红细胞效果差异无统计学意义(P0.05);不同厂家滤器制备的同一规格悬浮去白细胞红细胞在血容量、血浆FHb水平方面比较,差异有统计学意义(P0.05);同一厂家滤器制备的悬浮去白细胞红细胞在不同储存期的FHb、保存期末溶血率差异有统计学意义(P0.05)。结论应从血细胞比容、FHb水平、溶血率等指标综合考虑,选择带白细胞滤器的一次性采血袋,以确保去白细胞效果及红细胞输注的安全性和有效性。     

库存血红细胞表面C3b、G6PD水平变化调查

目的 观察库存血有效期内红细胞表面C3b、G6PD水平变化过程,了解保存期库存血红细胞免疫功能及细胞膜的微观变化.方法 红细胞表面C3b采用卡式微柱凝胶法检测;G6PD采用自动生化分析仪检测.结果 陈旧库存血（采血30 d后）与新鲜库存血（采血7d内）比较,红细胞表面C3b、G6PD水平均显著下降.结论 有效期内库存血液保存时间越长,红细胞免疫功能越低,G6PD活性也相应减弱.这种变化应引起输血界重视.     

去除白细胞致红细胞参数变化的观察

目的 观察血液保存前去除白细胞红细胞不同时间的参数变化,以了解去除白细胞是否影响红细胞保存.方法 120袋血液分为两组,分别制备成普通悬浮红细胞(普通组)和悬浮少白细胞红细胞组(去白组),在滤除白细胞前、制备前、制备后和保存24 h、7、14、28、35 d,分别对红细胞平均体积(MCV)、平均血红蛋白(MCH)、红细胞分布宽度(RDW)进行检测,并染色计数异形红细胞百分比.结果 MCV、MCH在白细胞去除、成分制备及保存期无明显变化,RDW和异形红细胞百分比在成分制备后升高、保存24 h恢复原来水平;保存35 d时升高,以普通组更为明显.结论 去除白细胞对红细胞参数无明显影响,可能更有利于红细胞的保存.     

红细胞保存时间对受者中性粒细胞炎症释放水平的影响

目的 探讨研究红细胞随保存时间的延长对受者中性粒细胞炎症释放水平的影响.方法 分别将红细胞在保存的第1、14、21天（D1、D14、D21）分离上清,-20℃留存备用,然后将上述冻存的上清与健康受者中性粒细胞体外培养12 h后,再加入细菌脂多糖后培养12、24 h收集上清-20℃留存待检,最后采用酶联免疫分析法（ELISA）方法检测其白介素-6（IL-6）水平.结果 在红细胞在保存的第1、14、21天（D1、D14、D21）收集的未加中性粒细胞的红细胞上清,检测发现：无IL-6表达,而在细菌脂多糖的诱导下,IL-6浓度水平随时间变化逐渐增加,差异有统计学意义（P〈0.05）.观察组D1、D14和D21 IL-6水平分别高于对照组相应时间点的,差异有统计学意义（P〈0.05）.结论 在细菌脂多糖的刺激下,输注保存时间长的红细胞增强了中性粒细胞的炎症反应,保存时间一定程度上可预测大量输血后引发的相关免疫反应.     

IMMUNOHEMATOLOGY: Storage of murine red blood cells enhances alloantibody responses to an erythroid‐specific model antigen

BACKGROUND: Red blood cell (RBC) alloimmunization can be a serious complication of blood transfusion, but factors influencing the development of alloantibodies are only partially understood. Within FDA‐approved time limits, RBCs are generally transfused without regard to length of storage. However, recent studies have raised concerns that RBCs stored for more than 14 days have altered biologic properties that may affect medical outcomes. To test the hypothesis that storage time alters RBC immunogenicity, we utilized a murine model of RBC storage and alloimmunization. STUDY DESIGN AND METHODS: Blood from transgenic HOD donor mice, which express a model antigen (hen egg lysozyme [HEL]) specifically on RBCs, was filter leukoreduced and stored for 14 days under conditions similar to those used for human RBCs. Fresh or 14‐day‐stored RBCs were transfused into wild‐type recipients. The stability of the HOD antigen and posttransfusion RBC survival were analyzed by flow cytometry. RBC alloimmunization was monitored by measuring circulating anti‐HEL immunoglobulin levels. RESULTS: Transfusion of 14‐day‐stored, leukoreduced HOD RBCs resulted in 10‐ to 100‐fold higher levels of anti‐HEL alloantibodies as detected by enzyme‐linked immunosorbent assay than transfusion of freshly collected, leukoreduced RBCs. RBC expression of the HOD antigen was stable during storage. CONCLUSIONS: These findings demonstrate that HOD murine RBCs become more immunogenic with storage and generate the rationale for clinical trials to test if the same phenomenon is observed in humans. Length of storage of RBCs may represent a previously unappreciated variable in whether or not a transfusion recipient becomes alloimmunized.     

Transfusion of fresh murine red blood cells reverses adverse effects of older stored red blood cells

BACKGROUND: Although a subset of recent studies have suggested that red blood cell (RBC) storage length is associated with adverse patient outcomes, others have shown no such relationship. Adults may be transfused with RBC units of different storage lengths, and existing studies do not take into consideration that fresh RBCs may alter responses to concurrently transfused stored RBCs. To test this possibility, we utilized a murine model and investigated transfusion outcomes of fresh, stored, or fresh‐plus‐stored RBCs. STUDY DESIGN AND METHODS: Fresh, 14‐day‐stored or fresh plus 14‐day‐stored leukoreduced RBCs from HOD‐transgenic donors (with RBC‐specific expression of hen egg lysozyme, ovalbumin, and human Duffy^b) were transfused into naïve C57BL/6 recipients. Serum cytokines and anti‐HOD alloimmunization were evaluated after transfusion. RESULTS: In six of six experiments (n = 90 mice total), a proinflammatory serum cytokine storm of interleukin‐6, keratinocyte‐derived chemokine/CXCL1, and monocyte chemoattractant protein‐1 was observed in transfusion recipients of stored but not fresh RBCs, along with high degrees of anti‐HOD alloimmunization. However, concurrent transfusion of fresh HOD RBCs along with stored HOD RBCs significantly decreased these adverse outcomes (p < 0.05). CONCLUSIONS: These results are consistent with fresh murine HOD RBCs losing protective properties during storage, and introduce a previously unrecognized variable in RBC storage studies. If translatable to humans, uniform “old blood” groups may be needed in future clinical studies to more accurately investigate the biologic effects of older RBC units.     

Transfusion of stored red blood cells adhere in the rat microvasculature

BACKGROUND: Ex vivo storage of red blood cells (RBCS) for transfusions is associated with a “storage lesion,” which decreases RBC deformability and increases RBC adhesiveness to vascular endothelium. This may impair microcirculatory flow with deleterious effects on oxygen delivery after transfusion. Previous studies have shown that human RBCs adhere to endothelial monolayers in vitro with prolonged storage and is reduced by prestorage leukoreduction (LR). The objective of this study was to determine whether duration of RBC storage and LR influence RBC adhesion in vivo in capillaries. STUDY DESIGN AND METHODS: Rat RBCs were collected and stored in CPDA‐1 under standard blood bank conditions. Three RBC products were compared: 1) fresh RBCs, less than 24 hours of storage (n = 6); 2) nonleukoreduced (NLR) RBCs stored for 7 days (n = 6); and 3) prestorage LR RBCs stored for 7 days (n = 6). RBCs were labeled with fluorescein isothiocyanate (FITC) 24 hours before transfusion and reinjected in an isovolemic manner into healthy rats. The FITC‐labeled RBCs were visualized in the extensor digitorum longus muscle using intravital video microscopy (20× magnification). The number of RBCs adherent in capillaries was counted 1 hour after transfusion in 10 random fields and the median values were compared with one‐way analysis of variance. RESULTS: Stored RBCs showed increased levels of adherence in capillaries compared to their fresh counterparts (p < 0.05). Prestorage LR decreased RBC adherence to levels equivalent to those of fresh RBCs (p < 0.05 for stored LR vs. stored NLR). CONCLUSION: Rat RBCs stored under conditions that closely mimicked clinical transfusion adhere in capillaries. The decreased RBC adherence with LR suggest a direct effect of white blood cells or their byproducts on RBC deformability and/or adhesiveness to microvascular endothelium. Further study will examine the mechanism of adherence and the impact it has on microcirculatory flow and oxygen delivery in the critically ill host.     

Red blood cell storage and cell morphology

Aim: In this study, we performed weekly assessment of morphology‐related parameters through monitoring of CPD‐SAGM leuco‐filtered erythrocyte concentrates from blood withdrawal until the 42nd day of storage. Background: Liquid storage of red blood cells (RBCs) delivers a blood‐derived therapeutic, which is safe, available, effective and affordable for most patients who need transfusion therapy in developed countries. However, a growing body of accumulating controversial evidences, from either biochemical or retrospective clinical studies, prompted safety concerns about longer stored RBCs. Methods: Statistical image analysis through scanning electron microscope was coupled to osmotic fragility and erythrocyte sedimentation rate. Results: We could observe that by day 21 more than 50% of RBCs displayed non‐discocyte phenotypes. This observation was related to an increase in osmotic fragility, which was totally overlapped in day 0 controls and day 7 RBCs while only slightly augmented in day 14 samples. Cation dysregulation (pH internal/external alteration and potassium) might both reflect and trigger a negative feedback loop with metabolic fluxes and membrane cation pumps. Conclusion: Morphology parameters suggest that significant alterations to RBC morphology over storage duration occur soon after the 14th day of storage, as to become significant enough within the 21st day.     

Diabetes augments and inhaled nitric oxide prevents the adverse hemodynamic effects of transfusing syngeneic stored blood in mice

BACKGROUND: Stored red blood cells (RBCs) undergo progressive deleterious functional, biochemical, and structural changes. The mechanisms responsible for the adverse effects of transfusing stored RBCs remain incompletely elucidated. STUDY DESIGN AND METHODS: Awake wild‐type (WT) mice, WT mice fed a high‐fat diet (HFD‐fed WT) for 4 to 6 weeks, and diabetic (db/db) mice were transfused with syngeneic leukoreduced RBCs or supernatant with or without oxidation (10% of total blood volume) after storage for not more than 24 hours (FRBCs) or 2 weeks (SRBCs). Inhaled nitric oxide (NO) at 80 parts per million was administered to a group of mice transfused with SRBCs. Blood and tissue samples were collected 2 hours after transfusion to measure iron and cytokine levels. RESULTS: SRBCs had altered RBC morphology and a reduced P₅₀. Transfusion of SRBCs into WT or HFD‐fed WT mice did not produce systemic hemodynamic changes. In contrast, transfusion of SRBCs or supernatant from SRBCs into db/db mice induced systemic hypertension that was prevented by concurrent inhalation of NO. Infusion of washed SRBCs or oxidized SRBC supernatant into db/db mice did not induce hypertension. Two hours after SRBC transfusion, plasma hemoglobin (Hb), interleukin‐6, and serum iron levels were increased. CONCLUSION: Transfusion of syngeneic SRBCs or the supernatant from SRBCs produces systemic hypertension and vasoconstriction in db/db mice. It is likely that RBC storage, by causing in vitro hemolysis and posttransfusion hemoglobinemia, produces sustained NO scavenging and vasoconstriction in mice with endothelial dysfunction. Vasoconstriction is prevented by oxidizing the supernatant of SRBCs or breathing NO during SRBC transfusion.     

Frequency of glucose‐6‐phosphate dehydrogenase–deficient red blood cell units in a metropolitan transfusion service

BACKGROUND: Glucose‐6‐phosphate dehydrogenase (G6PD) deficiency is characterized by red blood cell (RBC) destruction in response to oxidative stress. Although blood donors are not routinely screened for G6PD deficiency, the transfusion of stored G6PD‐deficient RBCs may have serious adverse outcomes. By measuring G6PD enzyme activity of RBC units from a large metropolitan hospital transfusion service, we sought to determine 1) the prevalence of G6PD‐deficient RBC units, 2) if G6PD activity changes during storage, and 3) if G6PD activity in segments correlates with its activity in the bags. STUDY DESIGN AND METHODS: Quantitative G6PD activity was measured in 301 randomly selected RBC units and 73 D+C?E? (i.e., R₀r or R₀R₀) RBC units, all stored in additive solutions. G6PD deficiency was defined as activity less than 60% of the normal mean. RESULTS: The frequency of G6PD‐deficient units in the general inventory was 0.3% (1/301; 95% confidence interval [CI], <0.01%‐2.1%). In contrast, its frequency in D+C?E? RBC units was 12.3% (9/73; 95% CI, 6.4%‐22.0%). G6PD activity did not significantly change during the 42‐day storage period, and G6PD activity measured in RBC storage bags and attached segments correlated well (r = 0.7‐0.9, p ≤ 0.001, Spearman rank correlation). CONCLUSIONS: Although the frequency of G6PD‐deficient RBC units in the transfusion service general inventory was relatively low, it was significantly higher among a subset of R₀r or R₀R₀ units. The latter are preferentially allocated for transfusion to patients with sickle cell disease to decrease the risk of RBC alloimmunization, possibly allowing more of these units to be inadvertently targeted to these patients.     

Transfusion of banked red blood cells and the effects on hemorrheology and microvascular hemodynamics in anemic hematology outpatients

BACKGROUND: The aim of this study was to investigate the effects of red blood cell (RBC) transfusion on the hemorrheologic properties and microcirculatory hemodynamics in anemic hematology outpatients receiving 2 to 4 RBC units of either “fresh” (leukoreduced storage for less than 1 week) or “aged” (leukoreduced storage for 3‐4 weeks) RBCs. STUDY DESIGN AND METHODS: Measurements were performed before and 30 minutes after RBC transfusion in hematology outpatients. Leukoreduced RBC suspensions were stored in saline‐adenine‐glucose‐mannitol (SAGM) additive solution. Whole blood viscosity was measured using Couette low‐shear viscometry, RBC deformability and aggregability were measured using laser‐assisted optical rotational cell analysis, and microcirculatory density and perfusion were assessed using sidestream dark field imaging. RESULTS: One group of patients (n = 10) received a median (interquartile range) of 3 (2‐3) RBC bags that were stored for 7 (5‐7) days (fresh) and the other group of patients (n = 10) received 3 (3‐3) RBC bags that were stored for 23 (22‐28) days (aged). After transfusion of fresh versus aged RBCs, hematocrit increased to 32 ± 3% versus 31 ± 2% (p < 0.363), whole blood viscosity increased to 4.2 ± 0.4 Pa/sec versus 4.2 ± 0.6 Pa/sec (p < 0.912), RBC deformability index remained unaffected, RBC aggregability index increased to 55 ± 10 versus 55 ± 13 (p = 0.967), microcirculatory flow remained unaffected, and microcirculatory density increased to 19.3 ± 2.5 mm/mm² versus 18.7 ± 1.9 mm/mm² (p = 0.595), respectively. CONCLUSION: Storing leukoreduced SAGM‐suspended RBCs for 3 to 4 weeks did not affect their ability to improve hemorrheologic properties and microcirculatory hemodynamics in our small group of anemic hematology outpatients. Larger studies are needed to confirm this finding.     

Proteomic analysis of supernatants of stored red blood cell products

BACKGROUND: The development of the red blood cell (RBC) storage lesion remains incompletely understood. To gain a greater insight into the mechanisms involved, a proteomics analysis was used to identify proteins that accumulate in supernatants of standard nonleukoreduced RBC products (S-RBCs) and prestorage leukofiltered RBC products (LF-RBCs) during storage. STUDY DESIGN AND METHODS: S-RBCs and LF-RBCs were collected and stored in accordance with standard blood bank procedures. Supernatant samples were collected at fortnightly intervals until product expiry (at Day 42). Maps of supernatant proteins were generated by two-dimensional (2D)-gel electrophoresis and selected proteins were identified by mass spectrometry. RESULTS: 2D-gel mapping revealed that greater numbers of proteins accumulated in supernatants of S-RBCs compared to LF-RBCs. Abundant plasma proteins were strongly represented in both products. Several potentially bioactive proteins were found to predominantly accumulate in supernatant of S-RBCs. Among these, a promoter of neutrophil adhesion and an acute-phase scavenger protein were identified. In contrast, proteins found to accumulate predominantly in supernatant of LF-RBCs were RBC-regulatory proteins. CONCLUSION: Proteomics provides a valuable approach to examine storage-related effects on RBCs. Such analytical approaches may help to elucidate the mechanisms involved in the RBC storage lesion and provide insights into the biologic consequences of transfusion of stored RBC products.     

Supernatant from stored red blood cell primes inflammatory cells: influence of prestorage white cell reduction

BACKGROUND: The contribution of RBC transfusion to adverse patient outcomes is controversial. There is conflicting clinical data and limited biologic data that provide an underpinning biologic rationale for any adverse impacts from RBC transfusion. This study used in-vitro measures of PMN stimulation to determine the ability of supernatant from RBCs to stimulate allogeneic WBCs and to determine the influence of residual donor WBCs and storage time on the proinflammatory potential of RBCs. STUDY DESIGN AND METHODS: Three types of RBCs were assessed: standard non-WBC-reduced RBCs (S-RBCs), buffy coat-poor RBCs (BCP-RBCs), and prestorage WBC-filtered RBC (LF-RBCs). Supernatant was collected weekly up to Day 42 of storage. PMN priming by supernatant from RBCs was determined by three methods: induction of CD11b expression on PMNs, induction of IL-8 release from PMNs, and the chemotactic effect of supernatant on PMNs. RESULTS: Supernatant from S-RBCs induced the expression of CD11b on PMNs, primed PMNs to release IL-8, and was chemotactic for PMNs. The magnitude of this PMN-priming progressively amplified with storage time. In contrast, supernatant from BCP-RBCs or LF-RBCs did not significantly prime PMNs. The PMN-priming effect of supernatant from RBCs correlated more closely with the level of MNCs in the RBCs than PMN content. CONCLUSION: Supernatant from stored S-RBCs prime unstimulated allogeneic PMNs in vitro. Prestorage buffy-coat WBC reduction was as effective as WBC depletion in abrogating this proinflammatory response elicited by supernatants from RBCs. The clinical consequences, if any, of these findings for transfusion recipients are unknown.