THE PRESERVATION OF LIVING RED BLOOD CELLS IN VITRO : I. METHODS OF PRESERVATION

Effects of osmolality and solutes on the morphology of red blood cells according to three-dimensional refractive index tomography

Phosphate-buffered saline (PBS) and Alsever's solution (AS) are frequently used as media in blood-related studies, while 0.9% normal saline (NS) is frequently used in transfusion medicine. Despite the frequent use, the effects of these solutions on the shape and volume of red blood cells (RBCs) have not been reported. We collected blood samples from five healthy adults and used three-dimensional refractive index tomography to investigate the changes in the morphology of RBCs caused by changes in osmolality and solutes at the single-cell level. After diluting 2 μL of RBCs 200-fold with each solution (PBS, AS, and 0.9% NS), 40 randomly selected RBCs were microscopically observed. RBC shape was measured considering sphericity, which is a dimensionless quantity ranging from 0 (flat) to 1 (spherical). RBCs in plasma or AS showed a biconcave shape with a small sphericity, whereas those in 0.9% NS or PBS showed a spherical shape with a large sphericity. Moreover, we confirmed that sodium chloride alone could not elicit the biconcave shape of RBCs, which could be maintained only in the presence of an osmotic pressure-maintaining substance, such as glucose or mannitol. Although 0.9% NS solution is one of the most commonly used fluids in hematology and transfusion medicine, RBCs in 0.9% NS or PBS are not biconcave. Therefore, as the debate on the use of NS continues, future clinical studies or applications should consider the effect of glucose or mannitol on the shape of RBCs.

Zacharias Dische and the discovery of feedback inhibition: A landmark paper published in the forerunner of Biochimie

Zacharias Dische's discovery of feedback inhibition in metabolism was one of the most important in the history of biochemistry. However, his paper was written and published under very difficult circumstances in wartime and passed almost completely unnoticed. It is almost never cited, and the discovery itself is usually attributed to later work of others. Here I provide a discussion of Dische's work, a translation of his paper into English, and a transcription of the original French version, which is almost unobtainable anywhere.

Re-introducing whole blood for transfusion: considerations for blood providers

Whole blood is the original blood preparation but disappeared from the blood bank inventories in the 1980s following the advent of component therapy. In the early 2000s, both military and civilian practice called for changes in the transfusion support for massive haemorrhage. The 'clear fluid' policy was abandoned and replaced by early balanced transfusion of platelets, plasma and red cells. Whole blood is an attractive alternative to multi-component therapy, which offers reduced hemodilution, lower donor exposure and simplified logistics. However, the potential for wider re-introduction of whole blood requires re-evaluation of haemolysins, storage conditions and shelf-life, the need for leucocyte depletion/ pathogen reduction and inventory management for blood providers. This review addresses these questions and calls for research to define the optimal whole blood product and the indications for its use.

Yeast-rich mannan fractions in duck cultivation: prospects of using

Introduction. Due to the trend of avoiding antibiotics and acquiring eco-friendly products, the use of environmentally safe preparations is becoming increasingly relevant in poultry farming. Study objects and methods. We used Salmonella enteritidis and Campylobacter jejuni isolated from poultry carcasses. At the first in vitro stage, we studied the ability of mannan oligosaccharides, isolated from the cell walls of Saccharomyces cerevisiae yeast, to adsorb bacterial pathogens. At the second stage, we studied the influence of fraction on the activity, colonization and microflora composition of ducklings’ intestines. At the third stage, we determined the antagonistic activity of Bifidobacterium spp. (Bifidobacterium lactis, Bifidobacterium longum, Bifidobacterium bifidum) and Lactobacillus spp. (Lactobacillus fermentun, Lactobacillus salivarius, Lactobacillus acidophilus) against Salmonella enteritidis and Campylobacter jejuni isolates. The experiment was conducted on the ducklings of Star 53 H.Y. cross. Their diet was supplemented with probiotics, prebiotics, and their combination. Results and discussion. In vitro studies showed the ability of mannan oligosaccharides isolated from the cell walls of Saccharomyces cerevisiae yeast to adsorb Salmonella enteritidis and Campylobacter jejun. In vivo experiment showed the ability of mannan oligosaccharides to prevent colonization of poultry intestines by bacterial pathogens with type I fimbriae. Conclusion. The reisolation rate of ducks infected with Salmonella enteritidis was 53.6% lower, and those infected with Campylobacter jejuni, 66.2% lower than the control. Mannan oligosaccharides added to the diet did not affect the concentration of lactobacilli, enterococci, and anaerobic bacteria in the ducks’ intestines. A combined use of Bifidobacterium spp. and mannan oligosaccharides improved the preservation of poultry stock by 8.7%, which made it an effective way to prevent poultry salmonellosis.

Simultaneous R2* and quantitative susceptibility mapping measurement enables differentiation of thrombus hematocrit and age: an in vitro study at 3 T

BACKGROUND

The efficacy of acute ischemic stroke treatment is affected by thrombus composition and age, yet no diagnostic method capable of quantitative thrombus characterization currently exists. This in vitro study evaluates the use of R_2^* , quantitative susceptibility mapping (QSM), and proton density fat fraction (FF) maps derived from a single gradient echo (GRE) MRI acquisition for characterizing clot of various hematocrit, as well as added calcified and lipidic components, throughout aging.

METHODS

Two thrombus phantoms containing porcine clots (10-60% hematocrit, one with added calcium or lard) were scanned serially throughout 6 days of aging. Three-dimensional multi-echo GRE imaging was used to generate R_2^* , QSM, and FF maps, from which mean values for all clots at every time point were obtained. Receiver operating characteristic analysis was used to derive thresholds differentiating acute from chronic clot, and measured R_2^* and QSM were tested for their ability to estimate clot hematocrit.

RESULTS

R_2^* and QSM varied minimally over the first 6 hours of aging (acute), and QSM was found to linearly relate to clot hematocrit. Beyond 6 hours (chronic), R_2^* and QSM increased considerably over time and hematocrit could be estimated from the R_2^* /QSM ratio. R_2^* and QSM thresholds of 22 s^-1 and 0.165 ppm differentiated acute from chronic clots with a sensitivity/specificity of 100%/100% and 85%/92%, respectively. QSM and FF maps definitively distinguished calcium and lipid, respectively, from clots of any hematocrit and age.

CONCLUSIONS

R_2^* , QSM, and FF from a single multi-echo GRE scan discriminated hematocrit and age, and distinguished calcification and lipid withinin vitro clot.

Citrate metabolism in red blood cells stored in additive solution-3

BACKGROUND

Red blood cells (RBCs) are thought to have a relatively simple metabolic network compared to other human cell types. Recent proteomics reports challenge the notion that RBCs are mere hemoglobin carriers with limited metabolic activity. Expanding our understanding of RBC metabolism has key implications in many biomedical areas, including transfusion medicine.

STUDY DESIGN AND METHODS

In-gel digestion coupled with mass spectrometric analysis proteomics approaches were combined with state-of-the-art tracing experiments by incubating leukofiltered RBCs in additive solution-3 for up to 42 days under blood bank conditions, in presence of ¹³ C_1,2,3 -glucose, 2,2,4,4-d-citrate, and ¹³ C,¹⁵ N-glutamine.

RESULTS

Results indicate that the pentose phosphate pathway/glycolysis ratio increases during storage in additive solution-3. While the majority of supernatant glucose is consumed to fuel glycolysis, incorporation of glucose-derived pentose phosphate moieties was observed in nucleoside monophosphates. Incubation with deuterated citrate indicated that citrate uptake and metabolism contribute to explain the origin of up to approximately 20% to 30% lactate that could not be explained by glucose oxidation and 2,3-diphosphoglycerate consumption alone. Incubation with ¹³ C,¹⁵ N-glutamine showed that glutaminolysis fuels transamination reactions and accumulation of millimolar levels of 5-oxoproline, while de novo glutathione synthesis was not significantly active during refrigerated storage.

CONCLUSION

Quantitative tracing metabolic experiments revealed that mature RBCs can metabolize other substrates than glucose, such as citrate, an observation relevant to transfusion medicine (i.e., formulation of novel additives), and other research endeavors where metabolic modulation of RBCs opens potential avenues for therapeutic interventions, such as in sickle cell disease.

Retrospective evaluation of the effect of red blood cell product age on occurrence of acute transfusion-related complications in dogs: 210 cases (2010-2012)

OBJECTIVE

To determine whether red blood cell (RBC) product age influences the occurrence of acute transfusion-related complications and mortality in dogs. The hypothesis was that acute transfusion-related complications and mortality would increase with age of product.

DESIGN

Retrospective study (2010-2012).

SETTING

University teaching hospital.

ANIMALS

Two hundred and ten clinical canine patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Medical records were reviewed for dogs receiving RBC-containing products. Patient signalment; reason for transfusion; product type, dose, age, and source; pretransfusion compatibility; rate, route, and method of administration; administration of multiple transfusions; underlying disease; occurrence of transfusion-related complications (eg, fever, hemolysis, gastrointestinal distress, cardiovascular, neurologic, and respiratory complications); various hematologic parameters; and survival were recorded. Data were analyzed for association between potential risk factors and occurrence of transfusion-related complications as well as between transfusion-related complications and survival. Of 333 transfusion events in 210 patients, 84 transfusion-related complications occurred. Fever was most common (41/333), followed by hemolysis (21/333). For every additional day of product age, the odds of hemolysis increased significantly (odds ratio, 1.11; 95% confidence interval, 1.06-1.16; P < 0.0001). Transfusion-related complications when considered as a whole were associated with higher dose of product, longer duration of administration per transfusion event, and immune-mediated disease, but not with source of product or general category of anemia. Administration rate was significantly slower in patients with febrile transfusion-related complications (P < 0.0001). Product age was not associated with increased mortality.

CONCLUSIONS

Age of stored RBC products is associated with increased risk of transfusion-related hemolysis, but not with fever. Prospective clinical studies evaluating the influence of storage duration on development of in vitro versus in vivo hemolysis are warranted.

Metabolomics in transfusion medicine

Biochemical investigations on the regulatory mechanisms of red blood cell (RBC) and platelet (PLT) metabolism have fostered a century of advances in the field of transfusion medicine. Owing to these advances, storage of RBCs and PLT concentrates has become a lifesaving practice in clinical and military settings. There, however, remains room for improvement, especially with regard to the introduction of novel storage and/or rejuvenation solutions, alternative cell processing strategies (e.g., pathogen inactivation technologies), and quality testing (e.g., evaluation of novel containers with alternative plasticizers). Recent advancements in mass spectrometry-based metabolomics and systems biology, the bioinformatics integration of omics data, promise to speed up the design and testing of innovative storage strategies developed to improve the quality, safety, and effectiveness of blood products. Here we review the currently available metabolomics technologies and briefly describe the routine workflow for transfusion medicine-relevant studies. The goal is to provide transfusion medicine experts with adequate tools to navigate through the otherwise overwhelming amount of metabolomics data burgeoning in the field during the past few years. Descriptive metabolomics data have represented the first step omics researchers have taken into the field of transfusion medicine. However, to up the ante, clinical and omics experts will need to merge their expertise to investigate correlative and mechanistic relationships among metabolic variables and transfusion-relevant variables, such as 24-hour in vivo recovery for transfused RBCs. Integration with systems biology models will potentially allow for in silico prediction of metabolic phenotypes, thus streamlining the design and testing of alternative storage strategies and/or solutions.

Blood at 70: its roots in the history of hematology and its birth

This year we celebrate Blood's 70th year of publication. Created from the partnership of the book publisher Henry M. Stratton and the prominent hematologist Dr William Dameshek of Tufts School of Medicine, Blood has published many papers describing major advances in the science and clinical practice of hematology. Blood's founding antedated that of the American Society of Hematology (ASH) by more than 11 years and Stratton and Dameshek helped galvanize support for the creation of ASH. In this review, I place the birth of Blood in the context of the history of hematology before 1946, emphasizing the American experience from which it emerged, and focusing on research conducted during World War II. I also provide a few milestones along Blood's 70 years of publication, including: the growth in Blood's publications, the evolution of its appearance, the countries of submission of Blood papers, current subscriptions to Blood, and the evolution of topics reported in Blood's papers. The latter provides a snapshot of the evolution of hematology as a scientific and clinical discipline and the introduction of new technology to study blood and bone marrow. Detailed descriptions of the landmark discoveries reported in Blood will appear in later papers celebrating Blood's birthday authored by past Editors-in-Chief.

Antifreeze peptides and glycopeptides, and their derivatives: potential uses in biotechnology

Antifreeze proteins (AFPs) and glycoproteins (AFGPs), collectively called AF(G)Ps, constitute a diverse class of proteins found in various Arctic and Antarctic fish, as well as in amphibians, plants, and insects. These compounds possess the ability to inhibit the formation of ice and are therefore essential to the survival of many marine teleost fishes that routinely encounter sub-zero temperatures. Owing to this property, AF(G)Ps have potential applications in many areas such as storage of cells or tissues at low temperature, ice slurries for refrigeration systems, and food storage. In contrast to AFGPs, which are composed of repeated tripeptide units (Ala-Ala-Thr)_n with minor sequence variations, AFPs possess very different primary, secondary, and tertiary structures. The isolation and purification of AFGPs is laborious, costly, and often results in mixtures, making characterization difficult. Recent structural investigations into the mechanism by which linear and cyclic AFGPs inhibit ice crystallization have led to significant progress toward the synthesis and assessment of several synthetic mimics of AFGPs. This review article will summarize synthetic AFGP mimics as well as current challenges in designing compounds capable of mimicking AFGPs. It will also cover our recent efforts in exploring whether peptoid mimics can serve as structural and functional mimics of native AFGPs.

Red blood cell storage in SAGM and AS3: a comparison through the membrane two-dimensional electrophoresis proteome

BACKGROUND

SAGM is currently the standard additive solution used in Europe, while AS-3 is the third additive solution that has been licensed in the USA, and is also the one used in part of Canada. Although AS-3 is based on a saline-adenine-glucose solution, it also contains citrate and phosphate. Storage of red blood cell concentrates in CPD-SAGM is known to lead to the accumulation of a wide series of storage lesions, including membrane protein fragmentation and vesiculation, as we could previously determine through 2-dimensional gel electrophoresis.

MATERIALS AND METHODS

Through 2D-SDS-IEF-polyacrilamide gel electrophoresis we performed a time course analysis (day 0, 21 and 42 of storage) of red blood cell membranes from leukocyte-filtered concentrates either stored in CPD-SAGM or CP2D-AS-3.

RESULTS AND DISCUSSION

From the present study it emerges that the membrane protein profile of red blood cells stored in presence of AS-3 appears to be slightly different from (better than) previous reports on SAGM-stored counterparts. However, the increase of total membrane spot number due to the presence of fragments at day 21 and the significant decrease at day 42 are suggestive of a universal phenomenon which is not efficiently tackled by either of the two additive solutions investigated in the present study.

CONCLUSION

To further delve into the storage lesion issue for RBCs stored in AS-3, it would be interesting in the future to assay metabolic changes over storage progression as well.

Cryopreservative effects of the recombinant ice-binding protein from the arctic yeast Leucosporidium sp. on red blood cells

Antifreeze proteins (AFPs) have important functions in many freeze-tolerant organisms. The proteins non-colligatively lower the freezing point and functionally inhibit ice recrystallization in frozen solutions. In our previous studies, we found that the Arctic yeast Leucosporidium sp. produces an AFP (LeIBP), and that the protein could be successfully produced in Pichia expression system. The present study showed that recombinant LeIBP possesses the ability to reduce the damage induced to red blood cells (RBCs) by freeze thawing. In addition to 40 % glycerol, both 0.4 and 0.8 mg/ml LeIBPs significantly reduced freeze-thaw-induced hemolysis at either rapid- (45 °C) or slow-warming (22 °C) temperatures. Post-thaw cell counts of the cryopreserved RBCs were dramatically enhanced, in particular, in 0.8 mg/ml LeIBP. Interestingly, the cryopreserved cells in the presence of LeIBP showed preserved cell size distribution. These results indicate that the ability of LeIBP to inhibit ice recrystallization helps the RBCs avoid critically damaging electrolyte concentrations, which are known as solution effects. Considering all these data, LeIBP can be thought of as a key component in improving RBC cryopreservation efficiency.

Blood Product Storage

Red blood cell transfusion therapy has been used with the ultimate goal of enhancing oxygen delivery to vital organs and tissue beds, thus enhancing cellular function. Red blood cell transfusion therapy is also a long-standing practice, and since the 1950s it has only grown in utilization, especially within the United States. Recently, transfusion therapy has come under increased scrutiny with a desire to develop evidence-based therapeutic guidelines that not only decrease undue risk to the patient but also decrease the overutilization of this high-cost, low-availability product. Despite the development and implementation of these guidelines, significant complications associated with red cell therapy persist and may be related to storage of blood products. Recently, within the transfusion literature, there has been a renewed focus on red cell storage lesions and their contributions to perioperative outcomes. Several meta-analyses, and now a recently launched, multinational randomized controlled trial, have been initiated to help bring clarity to whether or not the length of product storage has any effect on patient outcomes. This review will focus on the nature of storage lesions, complications associated with storage, as well as a brief review of some of the more provocative literature surrounding this controversial topic.

Scientific problems in the regulation of red blood cell products

BACKGROUND

For the past 30 years, red blood cell (RBC) storage systems have been licensed in the United States based on the demonstration that 24-hour in vivo recovery was greater than 75% and hemolysis was less than 1%. Now additional requirements for storage system licensure have being added. The meaning and value of these new requirements have been questioned.

STUDY DESIGN AND METHODS

The literature regarding the performance of present and suggested new tests for RBC licensure was reviewed.

RESULTS

(51) Cr 24-hr in vivo recovery has an intrinsic 4% error of measurement whereas the error in measures of hemolysis is less than 0.1%. Both measures have large donor-dependent end-of-storage variability; nevertheless, they have successfully guided RBC storage system development for six decades. Adenosine 5'-triphosphate and 2,3-diphosphoglycerate are difficult to measure accurately and international shared-sample studies suggest 6 and 11% coefficients of variation across laboratories. There is no readily available way to measure the oxygen equilibrium curve accurately. The new failure criteria provide no useful information and randomly fail good products.

CONCLUSIONS

Attempts to expand the useful regulatory requirements for RBC storage system licensure are limited by poor understanding of the storage lesion and its effect of RBC performance. Measures of (51) Cr 24-hour in vivo recovery remain critical and resources for this measure are limiting. The interaction between limited testing resources and large donor variability remains a major limit on RBC storage system development. It is important that new required tests contribute meaningful information and not make development and licensure of better products more difficult.

Effects of helicopter transport on red blood cell components

BACKGROUND

There are no reported studies on whether a helicopter flight affects the quality and shelf-life of red blood cells stored in mannitol-adenine-phosphate.

MATERIALS AND METHODS

Seven days after donation, five aliquots of red blood cells from five donors were packed into an SS-BOX-110 container which can maintain the temperature inside the container between 2 °C and 6 °C with two frozen coolants. The temperature of an included dummy blood bag was monitored. After the box had been transported in a helicopter for 4 hours, the red blood cells were stored again and their quality evaluated at day 7 (just after the flight), 14, 21 and 42 after donation. Red blood cell quality was evaluated by measuring adenosine triphosphate, 2,3-diphosphoglycerate, and supernatant potassium, as well as haematocrit, intracellular pH, glucose, supernatant haemoglobin, and haemolysis rate at the various time points.

RESULTS

During the experiment the recorded temperature remained between 2 and 6 °C. All data from the red blood cells that had undergone helicopter transportation were the same as those from a control group of red blood cell samples 7 (just after the flight), 14, 21, and 42 days after the donation. Only supernatant Hb and haemolysis rate 42 days after the donation were slightly increased in the helicopter-transported group of red blood cell samples. All other parameters at 42 days after donation were the same in the two groups of red blood cells.

DISCUSSION

These results suggest that red blood cells stored in mannitol-adenine-phosphate are not significantly affected by helicopter transportation. The differences in haemolysis by the end of storage were small and probably not of clinical significance.

Red blood cell storage lesions and related transfusion issues: a Canadian Blood Services research and development symposium

For centuries, man has been trying to figure out how to revive sick and traumatized individuals using fluids of various types, even from animals. In the 17th century, it was determined that blood was the best fluid to use and, in the early 1900s, after the discovery of the ABO blood groups, human blood was found to provide significant benefit for patients with shock and/or anemia. In the 1950s and 1960s, various ways to obtain, process, and store human blood were developed. It soon became apparent that storage of human blood for transfusion was problematic because red cells, as they aged in vitro, underwent a multitude of physicochemical changes that greatly affected their shelf life, the so-called storage lesion. More recently, the question has arisen as to the potential detrimental effects of the storage lesion and suggestions that older blood may induce increased morbidity and even mortality despite its acceptable in vivo survival. To address this issue of the efficacy and safety of transfusion of aged stored blood, a number of controlled clinical trials have been instituted to determine if older blood is significantly detrimental compared with fresher blood in transfusion recipients.

Evaluation of an 18-micron filter for use in reptile blood transfusions using blood from American alligators (Alligator mississippiensis)

Blood transfusions are a common therapeutic procedure in small animal medicine and have been investigated in some exotic species but little information is available about their safety and efficacy in reptiles. In human pediatrics and small animal practice, the Hemo-Nate18-micro filter is used to prevent embolic clots and particulate waste from entering the recipient during a transfusion. The goal of this study was to determine the hemolytic effect of an 18-micro Hemo-Nate filter for whole blood cell transfusions in reptiles using the American alligator (Alligator mississippiensis) as a reptilian model. Results revealed no significant difference in free plasma hemoglobin between the unfiltered and filtered samples (P = 0.21). There was no difference in the prefiltration and postfiltration packed cell volume (PCV) (P = 0.41). Results suggest that an 18-micro Hemo-Nate filter does not cause hemolysis or decrease the PCV of small quantities of alligator blood.

[Clinical impact of length of storage before red blood cell transfusion]

Presently, red blood cell units are stored up to 42 days in France and Canada. Length of storage of red blood cell units is not based on clinical outcomes: it is rather based on a decision made by some experts in the 1940s that red blood cell units can be stored as long as the average hemolysis is lower than 1% and the proportion of red blood cells still alive 24 hours post-transfusion is higher than 70%. Data reported recently suggest that transfusion with older red blood cell units may jeopardize the outcome of severely ill patients. In this paper, we comment the data already published on this question, and we summarize the randomized clinical trials presently on-going that were undertaken to address the relationship between length of storage of red blood cell units and outcomes of transfused patients.

Emerging Role for Use of Liposomes in the Biopreservation of Red Blood Cells

SUMMARY: Biopreservation is the process of maintaining the integrity and functionality of cells held outside the native environment for extended storage times. The development of red blood cell (RBC) biopreservation techniques that maintain in vitro RBC viability and function represents the foundation of modern blood banking. The biopreservation of RBCs for clinical use can be categorized based on the techniques used to achieve biologic stability, including hypothermic storage and cryopreservation. This review will examine the emerging role of liposomes in the RBC biopreservation, including the incorporation of liposomes into RBC membranes as an effective approach for minimizing RBC hypothermic storage membrane lesion and use of liposomes as a permeabilization strategy for the intracellular accumulation of novel intracellular cryoprotectants. Integration of current biopreservation research with blood banking practices offers enormous potential for future improvements of safety and efficacy of RBC transfusion.

Blood and war

In 1894 Ulsterman and pathologist Almroth Wright described the citation of blood. Twenty-one years later it was introduced into wartime and clinical practice. Harvard Medical School had a large part in providing Colonel Andrew Fullerton, later Professor of Surgery, Queen's Belfast, with the intellectual and practical help for the Allies to deploy blood on the post-Somme Western Front and in Salonika. The key investigators and clinicians were Americans and Canadians who with Fullerton and Wright instructed the Allies. The key enablers were two Harvard-trained surgeons surnamed Robertson-Oswald H. ("Robby") and L. Bruce (no relation). Physician Roger I. Lee of Harvard, surgeon George W Crile of Cleveland, Peyton Rous of the Rockefeller Institute and Richard Lewisohn of Mount Sinai Hospital, both located in the Upper East Side of New York City, played key roles.By Armistice in 1918, indirect citrated nutrient-enhanced blood transfusion was widely used by the Allies. Geoffrey Keynes was taught the techniques of blood transfusion by Dr. Benjamin Harrison Alton of Harvard at a Casualty Clearing Station near Albert at the time of the Battle of Passchendaele. Professor "Robby" Robertson, DSO, Sir Geoffrey Keynes and Sir Thomas Houston established blood banking.

FURTHER STUDIES ON THE SURVIVAL AND DEVELOPMENT IN VITRO OF A MALARIAL PARASITE

The survival of Plasmodium lophurae in vitro is favored by the presence of calcium pantothenate (0.02 mg. per ml). Survival of about 2 weeks in vitro at 40–41°C. has been obtained under the following conditions: a medium consisting of duck red cell extract in balanced salt solution with glutathione and glucose or glycogen, serum, embryo extract, and calcium pantothenate; daily replacement of about half of the medium with fresh medium; addition of fresh uninfected erythrocytes every 2nd day; gentle agitation of the preparation on a rocking machine. In some of these preparations significant increases in male gametocytes and, more rarely, in total numbers of parasites occurred during the first few days.

A METHOD FOR OBTAINING SUSPENSIONS OF LIVING CELLS FROM THE FIXED TISSUES, AND FOR THE PLATING OUT OF INDIVIDUAL CELLS

Individual, living, tissue cells can be obtained in suspension by digesting with trypsin the clot of growing tissue cultures. Under these circumstances the living cells assume a spherical form. When washed and plated in fresh plasma they put out processes and proliferate. After growth in the new plates has occurred the digestion and plating can be repeated. The limits of the method have not yet been reached. We are at work on a number of the problems which it has opened up.

STUDIES ON THE TOTAL BILE : II. THE RELATION OF CARBOHYDRATES TO THE OUTPUT OF BILE PIGMENT

Carbohydrate feeding or injection produces often a temporary increase in the rate at which bilirubin is put forth in the bile, but none in the amount of the pigment secreted from day to day. There would appear to be no ground for the supposition that bilirubin is normally derived in part from the carbohydrates of the food.

ON INDIVIDUAL DIFFERENCES IN HUMAN BLOOD

A clear-cut differentiation of human blood, aside from the blood groups, could be made by means of special agglutinating immune sera. The observations point to the existence of several agglutinable factors for which no agglutinins are demonstrable in normal human sera. In view of the latter circumstance the results reported do not imply any change in the scheme of the four blood groups. The body of serological evidence leads to the inference of a high degree of biochemical differentiation among individuals.

THE RELATION OF THE MENINGES AND CHOROID PLEXUS TO POLIOMYELITIC INFECTION

Among the mechanisms which defend the body from infection with the virus of poliomyelitis is the meningeal-choroid plexus complex, which normally is capable of excluding the circulating virus from the central nervous organs. The complex plays a part also in preventing infection from virus present upon the nasal mucosa. Aseptic fluids which irritate, inflame, or even slightly alter the integrity of the meninges and choroid plexus diminish or remove their protective function. Normal monkey or horse serum, isotonic salt solution, and Ringer's and Locke's solutions, when injected into the meninges, promote infection with the virus of poliomyelitis introduced into the blood, the nose, or the subcutaneous tissues. Simple lumbar puncture and the withdrawal and return of the cerebrospinal fluid in normal monkeys, hemorrhage having been absolutely avoided, do not promote infection with virus injected into the blood; while the replacement of the cerebrospinal fluid of one monkey with that of another does in some instances lead to infection. Simple lumbar puncture attended with even very slight hemorrhage opens the way for the passage of the virus from the blood into the central nervous tissues, and thus promotes infection. Hence, changes in the structure or function of the meningealchoroid plexus complex, too slight to be detected by chemical and cellular changes in the cerebrospinal fluid or by morphological alterations, suffice to diminish in an essential manner its protective powers. Of all the irritant fluids tested, immune serum alone injected into the meninges is not succeeded by infection from the virus introduced into the blood. The protective property of the immune serum is capable of overcoming the promoting action of normal monkey and horse serum and the other irritants mentioned. The importance first of the meningeal-choroid plexus complex in preventing infection with the virus of poliomyelitis, and next of immune serum in offsetting the disadvantages and dangers arising from defects in the mechanism is apparent, as is the bearing of the experiments reported on the serum therapy of epidemic poliomyelitis.

EXPERIMENTS ON THE PRODUCTION OF SPECIFIC ANTISERA FOR INFECTIONS OF UNKNOWN CAUSE : I. TYPE EXPERIMENTS WITH KNOWN ANTIGENS-A BACTERIAL HEMOTOXIN (MEGATHERIOLYSIN), THE PNEUMOCOCCUS, AND POLIOMYELITIC VIRUS

Attempts to produce antisera in animals to combat specific infections are usually deferred until the cause of the infection has been isolated and grown in pure culture to furnish antigen. It has seemed to us that the fulfillment of these conditions might in some cases be rendered unnecessary through the use of infected tissue itself as an antigen, combined with selective absorption of the antiserum to rid it of elements injurious to the species furnishing the tissue. In order to test this possibility type experiments have been carried out with immune sera effective against known antigens of three different sorts: 1. Sera resulting from the injection of rabbits and a goat with normal guinea pig tissues and a bacterial hemotoxin, the megatheriolysin described by Todd, which hemolyzes guinea pig cells. The sera possessed strong antitoxins for the megatheriolysin but were fatal to guinea pigs. By the method of selective absorption they were rendered innocuous to these animals and were successfully used to protect them from lethal doses of the megatheriolysin. 2. Anti-rabbit dog sera containing antibodies protective against pneumococcus infection. Such sera, subjected to repeated absorption with rabbit red cells, proved capable of protecting mice from pneumococcus infection in exactly the same degree as the unexhausted serum; that is to say, they protected against 100 times the dose of pneurnococci that was fatal with normal dog serum. 3. The serum of a monkey recovered from poliomyelitis and repeatedly injected with human red cells and extract of placental tissue. This serum, after selective absorption with human red cells, protected a monkey against an intracerebral dose of poliomyelitic virus fatal to eight other monkeys given it with normal monkey or human serum. The results in these instances, purposely chosen for their simplicity, would seem to indicate for the absorption method some usefulness in the study of immunity to infections of unknown cause. In Part II of our paper the method is applied to one such infection; namely, a sarcoma of the fowl engendered by a filterable agent. A general discussion will be found in connection with this portion of the work.

FREEZING POINTS OF ANTI-COAGULANT SALT SOLUTIONS

By a method involving equilibration of ice and solution, and analysis of the solution, freezing point depressions of solutions of sodium citrate, oxalate, and fluoride have been determined over the range Δ = 0.45 to 0.65°C. Determinations with sodium chloride solutions have confirmed the accuracy of the method. In each case the freezing point depression is given, within 0.002°C., as a linear function of the concentration. By the use of these linear equations it is possible to prepare a solution of any of these four salts isotonic with a given biological fluid of known freezing point, provided the latter falls within the range studied.

THE FIXATION AND PROTECTION OF VIRUSES BY THE CELLS OF SUSCEPTIBLE ANIMALS

Methods were developed for a study of the relations existing between viruses and living cells. It was found that vaccinia and the virus causing the infectious fibroma of rabbits (Shope) rapidly become fixed upon tissue cells freed as individuals and submitted to virus in suspension. This happens whether the cells are alive or have been killed with heat or ultraviolet light. The virus does not come away during agitation of the cells with Tyrode solution and repeated washings with large amounts of it. The exposure to neutralizing antisera of cells carrying virus fails to affect this latter significantly if the cells are alive, whereas if they are dead the activity of the virus is nullified. Cells freed as individuals from tissue cultures of vaccinia and the Shope tumor carry these viruses in abundance through repeated washings, and, if living, protect them from the influence of a neutralizing serum, whereas killed cells exert no such protection. The findings would appear to throw light on the way in which viruses gain a foothold in the host; and they suggest reasons for the persistence of some viruses in recovered animals and for the unsatisfactory results of serum treatment instituted during the course of virus diseases. The virus causing the Shope fibroma has been successfully maintained in cultures of the growth. It is closely associated with the cells, almost none being present in the culture fluid. Certain of its other attributes have been determined. Vaccinia greatly damages the cells of cultures of rabbit embryo in which it is under propagation.

STUDIES ON PNEUMOCOCCUS GROWTH INHIBITION : II. A METHOD FOR DEMONSTRATING THE GROWTH-INHIBITORY AND BACTERICIDAL ACTION OF NORMAL SERUM-LEUCOCYTE MIXTURES

Somewhat discordant results which have been reported by others who have investigated the property of the whole blood of resistant animals to cause inhibition of growth or death of pneumococci have led us to investigate this matter and to develop a new technique in which the conditions as they are present in the animal body are more nearly imitated. The observations already made have rendered it probable that phagocytosis plays some rôle in any destructive power for pneumococcus which whole blood possesses. We have, therefore, employed mixtures of serum and leucocytes in our tests, since when blood is coagulated the conditions become highly artificial. Furthermore, in order to imitate more nearly the conditions in the circulating blood the mixtures have been constantly, though gently, agitated. For this purpose a specially devised apparatus has been employed. The mixtures of serum and leucocytes have been inoculated with varying numbers of pneumococci in the active growth phase and after varying intervals of time the tubes containing the mixtures of serum, leucocytes, and bacteria have been opened, examined microscopically, and cultures made. Employing this technique it has been found that the growth of pneumococci having low virulence for cats is markedly inhibited in mixtures of cat serum and cat leucocytes. It was impossible to recover pneumococci from the tubes showing no apparent growth, either when the contents were transplanted into various kinds of culture media, or when the contents were injected into mice of a variety highly susceptible to pneumococcus infection. 10,000 times the number of pneumococci sufficient ordinarily to kill a mouse failed to do so after a 24 hour sojourn in the cat serum-leucocyte mixture. Mixtures of dog serum and leucocytes exert a similar action. The serum and leucocytes of animals susceptible to pneumococcus infection (rabbits and guinea pigs,) on the other hand, failed to injure pneumococci even in extremely small quantities. These results indicate that the blood of resistant animals, at least of the dog and cat, possesses destructive properties for pneumococci, and that this destructive power is not possessed by the blood of certain susceptible animals. The experiments suggest that natural immunity depends chiefly, if not entirely, upon this property. The leucocytes play an active part in this process, but whether the destruction of the pneumococci occurs entirely within the leucocytes or not is not determined. That the serum also plays a part is shown by the fact that when the serum of resistant animals was inactivated before being used in the serum-leucocyte mixture, the growth of even very small numbers of pneumococci was not prevented. Further experiments with cat serum and leucocytes were carried out to determine the optimum rate and time of agitation, the amount of serum and leucocytes required, and also the period of incubation necessary for the inhibition of growth and death of the pneumococci to occur.

STUDY OF TRANSFUSED BLOOD : I. THE PERIODICITY IN ELIMINATIVE ACTIVITY SHOWN BY THE ORGANISM

Group IV transfused blood in a recipient of unlike group is eliminated by a blood-destroying activity of the body. This blood-destroying activity is periodic both in men and women, and in women coincident with menstruation. The elimination of the transfused blood probably takes place as part of a period of blood-destroying and blood-producing activity of the body, although direct evidence to this effect is so far lacking.

STUDIES ON PNEUMOCOCCUS GROWTH INHIBITION : I. THE PROTECTIVE ACTION OF GELATIN FOR PNEUMOCOCCI IN SUSPENSION

Experiments were undertaken with the purpose of determining the type of non-nutrient fluid most suitable for the suspension of pneumococci with a minimum amount of injury. For comparative studies, dilutions in the various fluids tested were made from a standard suspension containing approximately 1,000 million pneumococci per cc. The protective properties of each solution were judged by the length of time viable organisms could be recovered (in culture) from a suspension containing 0.0000001 cc. of the standard suspension. The hydrogen ion concentration of the solutions, the temperature at which the suspensions were kept, and the culture media were carefully controlled. Furthermore, plates were made at the beginning of the experiment to determine the number of organisms present in a unit of suspension. It was found that pneumococci suspended in Locke's solution, 0.5 and 0.9 per cent NaCl solutions, and water, remained alive for only a few hours at most. Salt solution was shown to be the least suitable of these three; not infrequently by the time the 0.000001 cc. dilution in this fluid had been reached, the suspension was sterile. The addition, however, of 0.1 per cent gelatin to the above fluids transformed all, except 0.9 per cent NaCl, into highly favorable solutions. Pneumococci suspended in gelatin-water and gelatin-Locke's solution remained alive at room temperature for 6 to 7 days; in gelatin-salt 0.5 per cent solution, for at least 2 days. It was possible to vary the H ion concentration of the suspension fluids from pH 7.0 to 8.2 without any marked effect on the results. However, a pH of 7.4 to 8.0 appeared to be the most suitable. The nature of the protective action of gelatin was investigated. Series of plates made at frequent intervals failed to reveal any growth in suspensions of pneumococci containing this small concentration of gelatin. The beneficial effect of gelatin in the above solutions was found to lie largely in its protection of the pneumococci against the mechanical injury which occurs during the process of dilution in crystalloid solutions or water. Gelatin shows in addition a well marked preservative action, that is to say, it protected organisms against early dissolution. The nature of this preservation is uncertain. The presence of 0.1 per cent gelatin in 0.9 per cent NaCl failed to protect pneumococci against the toxic action of Na. But it was found possible to neutralize to a considerable degree this toxic effect of sodium by the addition of a small quantity (2 per cent) of a M/15 balanced phosphate mixture or sodium phosphate. In a gelatin-salt 0.9 per cent solution buffered with phosphate, pneumococci survived for 24 to 48 hours. Even in gelatin-salt, 0.5 per cent the presence of phosphate had a definite beneficial effect.

Red cell changes during storage

Red blood cells can be stored in liquid suspension in approved additive solutions for periods up to 6 weeks with 0.4% hemolysis, 84% 24-h in vivo recovery, and normal subsequent survival of the cells that persist in the circulation for at least 24h. However, while they are stored, the red cells undergo changes including the loss of adenosine triphosphate, diphosphoglycerate, and potassium, oxidative injury to proteins, lipids, and carbohydrates, loss of shape and membrane, increased adhesiveness, decreased flexibility, reduced capillary flow, and decreased oxygen delivery. Deaths have been reported related to the high potassium and lysophospholipids, but are rare.

Red blood cells from pluripotent stem cells for use in transfusion

The use of donated red blood cells in transfusion is a well-established cellular therapy. However, problems including insufficient supply, transfusion-transmitted infections and the need for immunological matching hamper even in the best services. These issues may be eliminated by using pluripotent stem cells to generate universal donor group O, Rhesus D-negative red blood cells. Human embryonic stem cells can be maintained and expanded indefinitely and can, therefore, produce the very large cell numbers required for this application. Red blood cell production is also an attractive goal for pluripotent stem cell-derived therapeutics because it is a well-characterized single cell suspension, lacking nucleated cells and with a low expression of HLA molecules. Much progress has been made; however, a number of challenges remain including scale-up, clinical effectiveness and product safety.

Red blood cell hemolysis during blood bank storage: using national quality management data to answer basic scientific questions

BACKGROUND

Hemolysis of red blood cells (RBCs) during blood bank storage is the most obvious manifestation of RBC storage system failure. However, its analysis is made difficult because the largest source of interunit difference is donor specific. Availability of data from national blood systems on large numbers of RBC units used for internal quality control (QC) purposes and stored and processed in uniform ways permits statistical analysis.

STUDY DESIGN AND METHODS

Measures of hemolysis during and at the end of storage on randomly selected donor units observed for QC purposes were obtained from four national blood systems. Groups of these measures from units that had undergone similar processing and storage were sorted to create histograms and the histograms were compared statistically.

RESULTS

A total of 14,087 measures were obtained under seven storage conditions, including more than 12,000 measures made in a single country under four closely related conditions. Distributions of percent hemolysis are skewed normal and outliers are random. Additive solutions appear to be equivalent, except that the 42 mmol/L mannitol in AS-1 reduces hemolysis compared to conventional 30 mmol/L mannitol in saline, adenine, glucose, and mannitol. Increasing storage from 35 to 42 days increased measured hemolysis by 30% and leukoreduction decreased it by 53%.

CONCLUSIONS

Large national data sets provide useful information about the distribution of hemolysis at the end of RBC storage. This information can aid blood storage system development and regulatory science.

Differential profiling of human red blood cells during storage for 52 selected microRNAs

BACKGROUND

MicroRNAs (miRNAs), the negative regulators of cellular mRNAs, are present in mature red blood cells (RBCs) in abundance relative to other blood cells. So far, there are no studies aimed at identifying large-scale miRNA profiles during storage of RBCs.

STUDY DESIGN AND METHODS

RNA samples from each RBC bag stored at 4 degrees C were collected on Days 0, 20, and 40 and subjected to miRNA profiling by using a membrane-based array. Fifty-two selected miRNAs of cellular apoptotic pathway represent the array. Through bioinformatics analyses, we identified potential target genes for selected miRNAs.

RESULTS

Differential profiling of RBCs for 52 miRNAs revealed two distinguishable patterns during storage: Forty-eight miRNAs demonstrated no trend at all, while four miRNAs, miR-96, miR-150, miR-196a, and miR-197, demonstrated an increase up to Day 20 and subsequently decreased during storage. We selected miR-96 and subjected it to standard bioinformatics analyses for target gene predictions, which identified several mRNAs including the RBC proapoptotic calpain small subunit-1 (CAPNS1) as potential targets of miR-96. To validate these predictions, we selected CAPNS1 mRNA as an example and confirmed its presence in the RBCs. Future experimental verification would help define miR-96-CAPNS1 interaction, if any, in the stored RBCs.

CONCLUSIONS

This study for the first time provided a differential profile of stored RBCs for selected miRNAs related to cellular apoptotic pathway and opened new avenues toward identification of novel in vitro RBC biomarkers of storage lesions. Future studies focusing on target gene-miRNA interactions in stored RBCs would also unravel underlying mechanisms of storage lesions.

Clinical impact of blood storage lesions

Recent reports suggest that transfusion of old red blood cell (RBC) units (>2 weeks) was associated with increased risks of postoperative complications and higher mortality rate caught public attention (Yap et al., Ann Thorac Surg 2008; 86:554-559 and Koch et al., 2008; 358:1229-1239). This rekindled the decades old discussion regarding the impact of RBC aging and storage lesions in patient care. The objectives of this review are to provide readers with an overview of the process of banking RBC that may have an impact on its quality, the reported clinical impact of storage lesions, the consequences of transfusing new RBC units only to the nation's blood supply and potential solutions that may improve the feasibility of blood banks to issue new blood units only.

Biopreservation of red blood cells--the struggle with hemoglobin oxidation

One of the least recognized causes of cellular damage during ex vivo preservation of red blood cells is oxidative injury to the hemoglobin. The latter has been associated with hemolysis through the release of toxic substances and oxidation of vital cell components. This review delineates some of the major pathways that link hemoglobin oxidation and cellular damage, and summarizes the incidence of red blood cell oxidative injury during hypothermic storage, cryopreservation and desiccation stress. Red blood cell hypothermic storage, despite its success, is not exempt from oxidative injury. Growing evidence portrays a time-dependant oxidative assault including formation of reactive oxygen species, attachment of denatured hemoglobin to membrane phospholipids and the release of hemoglobin-containing membrane microvesicles throughout storage. Similar symptoms have been observed in attempts to stabilize red blood cells in the dried state, in which methemoglobin levels of reconstituted red blood cells reached 50%. Factors affecting the rate of hemoglobin oxidation during red blood cell ex vivo storage include compromised antioxidant activity, high concentrations of glucose in the storage media and the presence of molecular oxygen. Hemoglobin oxidation largely dictates our ability to effectively preserve red blood cells. Understanding its origins along with investigating methods to minimize it can significantly improve the quality of our future blood products.

Red cell storage

Blood component storage allows the donor and recipient to be separated in time and space. This separation converts transfusion from a desperate clinical act into a planned, orderly healthcare logistic activity with concomitant increases in both blood product availability and safety. However, storage has the potential to reduce the efficacy of transfused blood components by reducing their flow, functional capacity, and survival. Storage time also allows the accumulation of leaked potassium from red cells and the growth of contaminating bacteria. Many different aspects of the red cell storage lesion have been described, including changes in metabolism, shape, and rheology changes, loss of membrane carbohydrates, lipids and proteins, and alterations in secretion, oxygen delivery, and adhesion. What has been harder to show is that these known changes have significant clinical effects. Therefore, regulatory decisions about product storage have been conservative, and largely based on historic patterns of use. The increasing power of proteomics and metabolomics offers the potential of deeper understanding of blood function and storage and of better clinical products in the future.