Platelet Storage Lesions in Second-Generation Containers: Correlation with in vivo Behavior with Storage up to 14 Days

The relationship between in vivo behavior and in vitro characteristics of 59 platelet concentrates (PC) stored for up to 14 days in a synthetic medium or in CPDA-1 plasma was systematically investigated. 25 paired studies (1 study was incomplete) were performed comparing platelets suspended either in the synthetic medium or CPDA-1 plasma with 5 days (n = 5); 7 days (n = 10); 10 days (n = 5); and 14 days (n = 5) of storage. In addition, 10 control studies were performed with freshly prepared PC (6-24 h) in CPDA-1 plasma. Both percent recovery and survival estimations showed decreases with increasing storage duration, irrespective of storage medium used. In both media, with prolonged storage, the platelet survival curves not only became shorter, but also increasingly exponential, suggesting that in vitro storage caused progressive damage to the platelets present in circulation. Survival curves of platelets suspended in synthetic medium remained more linear, indicative of less random damage during storage. Mean population lifespan (MPL) of the stored PC was determined by the area below the survival curve divided by the mean percent recovery for the fresh PC, which was 55%. MPL decreased from 4.5 days (fresh PC) to 0.4 days after 14 days of storage in plasma, with a 50% reduction (t1/2) estimated at 7.2 days of storage. MPL t1/2 for PC stored in the synthetic medium was estimated to be 8.8 days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Role of Lactate in Platelet Storage Lesion

It is known that lactate accumulation may cause a pH fall in platelet concentrates (PC) during storage, and this phenomenon causes platelet morphological lesions and loss of platelet in vivo viability. In this study, we added increasing amounts of lactate to identical PC in order to evaluate the role of hydrogen ion accumulation in determining platelet activation and lesion during storage. Six hours after PC preparation, lactate was added to PC1 and PC2 at 20 and 12 mM final concentrations, respectively, while PC3 served as control. In PC1, pH was lower than 6.3, and platelet function and discoid morphology were lost. PC2 were stored for 7 days at pH values ranging from 6.4 to 6.6, and most results of in vitro measurements reflecting platelet function such as osmotic reversal, ATP release and aggregation in response to different stimuli were not significantly inferior when compared to controls. The addition of lactate had no apparent effect on the rise of platelet activation markers P-Selectin, lysosome-like protein gp 53, platelet-bound fibrinogen and granulophysin, while a reduction of borderline significance was observed in glycoprotein Ib expression after pH reduction to values lower than 6.6. It is concluded that the rise of platelet activation markers during storage reflects platelet lesions different from those determined by lactate per se.     

The Platelet Storage Capability of Different Plastic Containers

Platelet concentrates (PC), prepared by platelet apheresis, were stored in four different types of blood bags. One of the bags, manufactured with a thinner PVC film than previously, was tested in three different bag volumes. From 25 donors a total number of 99 PC were prepared. Platelet numbers varied from 20 to 140 X 10(9) platelets per bag. The cell count, pH, pO2, pCO2 and lactate were determined initially and on days 1, 3 and 5 of storage. In a separate test, the oxygen diffusion capacity of the bags was determined by oxidation of sodium sulfite in the presence of cobaltous chloride. The oxygen diffusion capacity found was 16 (PL 732, 300 ml), 13.5 (Teruflexa 800 ml), 11.5 (PL 1240, 400 ml), 10.6 (Teruflexa 600 ml), 9 (Teruflexa 400 ml) and 4 (PL 146, 300 ml) mumol O2/h, respectively. For each bag type, the minimum and maximum platelet number stored with maintained pH levels (6.9-7.4) was defined. The maximum platelet number stored with maintained aerobic metabolism, correlated to the oxygen diffusion capacity of the bag, r = 0.998, p less than 0.001, n = 6; thus the maximum platelet number successfully stored for 5 days in each container can be predicted by determination of the oxygen diffusion capacity. In PC with a low platelet yield, pH values above 7.4 were observed after 1 and 3 days. When the results are compared with platelet yield data from routine blood banking, the optimal bags for platelet storage can be chosen. These conclusions must be further investigated in studies in vivo.     

5-Day Storage of Platelet Concentrates in CLX Containers: Effect of Type of Agitation

To determine the degree of platelet damage produced by different modes of agitation during storage of concentrates for 5 days in CLX blood bags, we studied pH, platelet counts, release of LDH and beta thromboglobulin, morphology and osmotic recovery. Platelets were maintained at 20-24 degrees C on elliptical, 6-rpm circular, 2-rpm circular and flat bed agitators. At 72-120 h platelet concentrates stored on the flat bed shaker had significantly lower pH values than units stored on the elliptical or on either of the circular rotators (p less than 0.05). The percent LDH discharged was highest for the units stored on the elliptical rotator (p less than 0.05). Remaining tests of platelet function were not significantly different for concentrates stored on any of the four agitators. Flat bed shakers were unable to resuspend the platelet 'button' which formed after the final preparative centrifugation. Based on our in vitro studies, we conclude that due to problems with low pH values, flat bed shakers may not be optimal for storing platelet concentrates in CLX blood bags and that some other form of agitation should be used.     

Influence of Storage Time on Activation of Platelets Collected with CS 3000 Plus and Cobe Spectra Using Platelet Storage Containers

Abstract: The aim of this study was to evaluate the in vitro activation in platelet suspensions collected with CS 3000 Plus and Cobe Spectra cell separators using platelet storage containers and the role of white blood cell (WBC) concentration of the suspension in this activation. Seventy‐seven donors were subjected to automated platelet donations with 1 type of equipment (37 with Cobe Spectra and 40 with CS 3000 Plus). Blood samples were obtained immediately after separation and on the third day of storage at 22°C in constant agitation. The WBC concentrations of these samples were studied before storage. Paraformaldehyde‐fixed platelets were incubated with 2 murine monoclonal antibodies: CD42b and CD62. Murine monoclonal antibody immunoglobulin G was used as a negative isotypic control. Bound antibody was then quantitated by flow cytometry. On the third day of storage, a significant increase in CD62 expression rate was observed in platelet suspensions collected with both kinds of equipment. Mean expression rates for Cobe Spectra on Day 0 and Day 3 were 25.6 ± 6.2% and 69.2 ± 9.7%, respectively. Mean expression rates for CS 3000 Plus on Day 0 and Day 3 were 23.4 ± 8.2% and 67.0 ± 8.2%, respectively. The mean results for both devices were 22.8 ± 4.56% for Day 0 and 68.7 ± 13.2% for Day 3. There was no difference between CD42b mean fluorescence intensity on Days 0 and 3 for the 2 devices (p > 0.5). Mean WBC concentrations in the platelet suspensions for Cobe Spectra and CS 3000 Plus were 0.37 × 10³/μl and 0.42 × 10³/μl, respectively, and there was no relation between WBC concentration and increase in CD62 expression. Both kinds of equipment were found to be similar according to in vitro activation markers.     

Normal Viability of Platelet Concentrates Obtained from CPDA-1 Blood after Storage in CL-3000 Blood Containers

Platelet concentrates were obtained from blood anticoagulated with CPDA-1 and their viability after storage in CL-3000 containers for 72 h at 22°C and for 24 and 48 h at 4°C was studied using autologous reinfusion of ⁵¹Cr-labeled platelets. Yield and t_1/2 values after such storage were similar to those previously reported for other containers and anticoagulants. Survival of platelets stored at 22°C for 3 days was essentially normal with the expected yields for that duration of storage. As has been described for other containers, adenine has no adverse or beneficial effect on platelet viability when assessed with these methods.     

Platelet Levels in Infectious Mononucleosis

Platelet levels in 57 patients with infectious mononucleosis are recorded.Approximately 50 per cent of cases show some degree of thrombocytopeniaduring the first 4 weeks of the disease. Possible mechanisms for the changeare reviewed and other acute infections complicated by thrombocytopeniabriefly discussed.

Submitted on July 31, 1964 Accepted on September 29, 1964     

Platelet aggregation and release of ATP in patients with hepatic cirrhosis

The purpose of this study was to assess the platelet aggregation and releasable platelet ATP in patients with alcoholic cirrhosis (n = 10) and primary biliary cirrhosis (n = 10). In patients with liver disease a significant decrease was found in both adenosine diphosphate-induced aggregation (P less than 0.01) and collagen-induced aggregation (P less than 0.001) compared with that of controls, but there was no significant difference between the two groups of patients. Patients with primary biliary cirrhosis release smaller amounts of ATP than patients with alcoholic cirrhosis, and compared with the controls there was a significant (P less than 0.001) decrease in the releasable ATP in the patient groups. These results suggest that platelets are damaged during an intravascular activation (loss of granules), which gives rise to their subsequent hypo-function when tested in vitro.     

A Correlation of the Platelet Count with D-Dimer Levels as an Indicator for Component Therapy in Children with Dengue Hemorrhagic Fever

Dengue Fever (DF) may evolve into two life threatening forms—Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). DHF is associated with increased vascular permeability and plasma leakage causing thrombocytopenia and loss of clotting factors into the third space and may result in bleeding initially due to thrombocytopenia and later due to disseminated intravascular coagulation (DIC), often as a terminal event. Prompt recognition and treatment of minor bleeds in DF children with incipient DIC with component therapy may be associated with improved survival while failure to do so is usually catastrophic. A sensitive marker for early DIC is the presence of D-dimer (DD) in the blood. To determine the correlation between the severity of thrombocytopenia and early DIC in children with DHF. The impact of additional factors like age and shock will also be evaluated. Case control prospective study of 60 DHF sero -positive children (1–15 years) with thrombocytopenia. After clinical evaluation they were divided into two equal groups based on the degree of thrombocytopenia (more than/less than 30,000/mm³). PT/APTT and DD levels were estimated in all children of both groups and statistical correlation was done. There was no significant difference in the DD levels between the two groups. However, children in either group, presenting with clinical features of shock and thrombocytopenia had significantly higher DD levels. Empirical component therapy in children with DHF based purely on their low platelet counts may not be justified. However, in DHF children with thrombocytopenia and features of shock, aggressive component therapy may prevent subsequent bleeding and may be justified.     

Role of MicroRNA-326 and its Target Genes Bcl-xL and Bak as Potential Markers in Platelet Storage Lesion in Blood Banks

Platelet transfusion is crucial in the management of various conditions such as quantitative and qualitative platelet disorders. A serious problem that impacts public health is the shortage of Platelet concentrates (PCs) that frequently affect few blood donors’ countries, such as Egypt. This has necessitated the need to establish novel standards for determining the quality of PC during storage. It was found that microRNAs (miRNA) differential expression profile is a helpful tool for recognition of physiological platelet changes during storage. The aim of the current study was to highlight the role of platelet miRNA-326 and its putative target apoptotic genes, Bcl-xL and Bak, and their role in platelet storage lesion (PSL). Differential expression of miRNA-326 and its target genes in the apoptotic pathway, Bcl-xL and Bak was done using quantitative real time PCR (QR-PCR) on different storage points at day 0, day 3 and day 5 in blood bank. The results of the current study revealed over expression of miRNA-326 throughout days of storage resulted in down regulation of Bcl-xL gene and subsequently up regulation of Bak gene. MiRNA-326 contributes to platelet apoptosis and PSL through inhibition of anti-apoptotic Bcl-xL expression and enhancing pro-apoptotic Bak expression. Differential miRNA-326 and its target gene, Bcl-xL and Bak, expression levels at different points of platelets storage are promising tools as biomarkers for platelets undergoing PSL in blood banks.     

Platelet Antiheparin Activity: Storage Site and Release Mechanism

The platelet storage and release mechanisms for the heparin-neutralizing activity(HNA), adenosine diphosphate (ADP),serotonin, and lysosomal enzymes wereinvestigated in normal human plateletsand in platelets with defective storageor release of ADP and serotonin. The timecourse of release of HNA from normalwashed platelets by thrombin and collagen was slower than that of serotonin.Lysosomal enzymes were not released bycollagen from normal washed platelets,whereas under the same conditions HNAwas released. In four of six patients withstorage pool deficiency, the platelets contained normal amounts of HNA but definitely decreased amounts of ADP andserotonin, whereas in the remaining twopatients the total contents of ADP, serotonin, and HNA were all definitely lowerthan normal. In four of six patients withstorage pool deficiency, the amounts andper cents of total HNA released by collagen were normal, whereas the amountsand per cents of total ADP released werediminished compared with normal. Platelets from patients with the aspirinlikeplatelet release defect and from aspirin-treated normal subjects contained normalquantities of ADP, serotonin, and HNA, butHNA and ADP were not released in response to collagen. It is concluded thateither HNA is stored in and released fromdense granules by mechanisms differentfrom those for ADP and serotonin, or thatHNA is stored in and released fromgranules other than the dense granules,which contain ADP and serotonin and the-granules, which contain lysosomalenzymes.

Submitted on January 7, 1974 Revised on February 11, 1974 Accepted on February 12, 1974     

Alternative Fuels for Platelet Storage: A Metabolic Study

We have studied the metabolism of platelets in vitro using washed platelets. Oxygen uptake and fuel utilization were measured. It was found that glucose is never oxidized to any significant extent and is always converted to lactate, regardless of oxygen availability. Oxidative metabolism fuels 70-100% of the ATP turnover, and oxygen uptake is the same whether the platelet is consuming glucose, acetate or only an unidentified endogenous fuel. When acetate is the added fuel, no endogenous fuel is oxidized, whereas the addition of glucose results in sparing of only 8% of endogenous fuel. Preliminary storage experiments using plasma-free media show that an acetate-containing buffered salt solution provided excellent storage conditions and that a medium without any exogenous fuel is better than one containing glucose. Thus we conclude that a successful storage medium should contain minimal amounts of glucose, and an oxidizable fuel such as acetate, in order to supplement the endogenous one.     

Platelet Storage in Glow Discharge-Treated Polyvinylchloride Bags: Effects of a Plasticizer on Platelet Hypotonic Shock Response

The effect of a plasticizer (DEHP) of PVC blood bags on platelet response to hypotonic shock was examined. The response of the platelet concentrate (PC), stored in the bag in which DEHP elution was prevented by glow-discharge treatment, did not change until 72 h of storage. On the other hand, during PC storage in control bags or in plasma containing DEHP, the response decreased approximately linearly. The time course of DEHP incorporation into platelet agreed well with that of the decrease of the response to hypotonic shock.     

急性心肌梗死患者血浆同型半胱氨酸水平与冠状动脉病变的相关性研究

目的检测急性心肌梗死(AMI)患者血浆同型半胱氨酸的水平,观察高同型半胱氨酸血症(HHcy)与冠状动脉病变的相关性以及与其他危险因素的相关性,以探讨HHcy在心血管疾病中的作用。方法选择AMI患者50例,对照组为冠状动脉正常者共30例。检测血浆同型半胱氨酸(Hcy)、血糖(GLU)、血脂、C反应蛋白(CRP)、脑钠肽(BNP)。行心脏彩超检查记录E/A,左室射血分数(LVEF)。行冠状动脉造影记录冠状动脉病变支数、狭窄程度。结果冠状动脉三支病变组Hcy水平高于对照组〔(34.69±10.31)μmol/L,(9.57±2.57)μmol/L,P<0.05〕。冠状动脉三支病变组血浆Hcy水平高于双支病变组和单支病变组〔(46.78±2.42)μmol/L,(34.88±3.39)μmol/L,(22.36±3.24)μmol/L〕,冠状动脉双支病变组血浆Hcy水平高于单支病变组〔(34.88±3.39)μmol/L,(22.36±3.24)μmol/L〕,差异均有统计学意义(P<0.01)。AMI组中IRA狭窄程度100%组血浆Hcy水平高于100%>IRA≥95%组〔(37.27±10.06)μmol/L,(31.39±9.89)μmol/L,P<0.05〕(1例IRA狭窄程度<75%除外)。AMI组血浆Hcy与BNP呈正相关(r=0.162,P<0.05),与LVEF呈负相关(r=-0.235,P<0.05),与E/A无相关(r=0.072,P>0.05)。结论 (1)AMI患者血浆Hcy水平明显升高。(2)AMI患者血浆Hcy水平与冠状动脉病变支数、狭窄程度呈正相关。(3)HHcy可以作为冠心病的一个危险因素,与其他危险因素共同在冠心病的发生、发展中起重要作用。     

高敏C反应蛋白、同型半胱氨酸和不稳定型心绞痛患者冠脉病变程度的相关性研究

目的探讨高敏C反应蛋白（hs-CRP）及同型半胱氨酸（Hcy）与不稳定型心绞痛（UA）患者冠脉病变程度的相关性。方法处纳入45例经冠脉造影证实的不稳定型心绞痛（UA）患者,31例经冠脉造影证实的非冠心病对照组患者,测定血脂、血糖、hs—CRP及Hcy,据冠脉造影结果,使用Gensini积分法将UA患者分组,评价hs—CRP及Hcy与UA患者冠状动脉病变程度的关系。结果UA患者hs—CRP及Hcy水平高于对照组,差异有统计学意义（p〈0．05）,应用Logistic回归模型将混杂因素矫正后分析hs—CRP及Hcy与UA的关系时,hs—CRP与UA相关（p〈0．05）;hs—CRP及Hcy与UA患者冠脉病变程度无明显相关（p〈0．05）。结论（1）不稳定型心绞痛患者的Hcy和hs—CRP表达增加;（2）hs—CRP可能是UA的独立危险因素;（3）Hcy和hs—CRP增高的程度与冠脉病变狭窄程度无明显关联。