57. Jahrestagung der Deutschen Gesellschaft für Transfusionsmedizin und Immunhämatologie

Dr. Dr. LL.M.

Mag.pharm. MSc PhD

Optimizing a buffy coat pooling protocol for the production of pathogen inactivated double unit platelet concentrates

Blood Components

Optimierung eines Buffy-Coat Poolingprotokolls für die Produktion von pathogeninaktivierten Doppel-Thrombozytenkonzentraten

Worldwide, different methods for the production of pooled platelets (PPs) are used. In Europe, the primary approach for producing PPs is the buffy coat (BC) method, pooling 4 to 8 BCs to produce a single or double unit of platelets. We aimed to increase the yield of blood products by optimizing manufacturing steps, ranging from the whole blood unit to the pooling process.We compared five different pooling approaches by measuring the volume and the platelet concentrates. First, we measured PP (n=107) from a 5 BC pool concentrate, the standard product from our blood bank. Second, we switched from pooling 5 BCs to 6 BCs to increase the platelet count (n=110). Third, we used a new hematology analyzer (Symex XN-1000) equipped with a special mode to measure platelet concentrates (n=107). Fourth, we implemented an adjusted BC program on the blood cell separators to produce a higher volume in the BC and the PP (n=107). Fifth, we adapted the second (soft) spin of our centrifugation protocol (n=197). The cutoff yield for dividing a concentrate is ≥ 4.4 unit.Optimizing the manufacturing steps significantly increased the yield of the products (P&lt;0.001). The mean yield of the blood product was 2.83 (SD 0.39) for approach one, 3.12 (0.38) for approach two, 4.03 (0.49) for approach three, 4.30 (0.53) for approach four, and 4.81 (0.58) for approach five.In addition to increasing the number of BCs, optimizing BC volume, analyzer selection, and centrifuge protocol in the manufacturing process of PP shows that 6 BC are sufficient to produce double unit platelet concentrates, thereby reducing costs and minimizing waste of blood.Die Autor:innen haben keinen Interessenskonflikt offenzulegen.

Poster

Dr. rer. nat

Dr. sc. nat.

Dr. med.

Comparative in vitro analysis of red blood cell (RBC) quality during storage in pediatric-sized blood bags using DEHP (bis(2-ethylhexyl) phthalate) vs. DINCH (cyclohexane-1,2-dicarboxylic acid) as plasticizer

In vitro Qualitätsanalyse von Erythrozyten bei Lagerung in DEHP (bis(2-ethylhexyl) phthalate)-haltigen Blutbeuteln für die Pädiatrie im Vergleich zum alternativen Weichmacher DINCH (cyclohexane-1,2-dicarboxylic acid)

DEHP is a plasticizer used in blood bags for decades but has been classified as CMR (cancerogenic, mutagenic, reprotoxic). Under the REACH regulation, manufacturers are obliged to remove DEHP from their products until December 2027. There is only limited in vitro data for red blood cell concentrates (RBCC) stored in blood bags containing alternative plasticizers. Data published so far indicates that the alternatives do not achieve the same quality characteristics as DEHP-containing blood bags.We compared red blood cells (RBC) stored in a standard blood bag system containing DEHP with a DEHP-containing alternative and a DEHP-free blood bag containing DINCH as plasticizer. We also analyzed the quality of γ-irradiated RBCC in the different blood bags. To create identical RBC content, RBCC in additive solution (PAGGS-M) were pooled and split into the three different blood bags. Storage effects were assessed on day 1 of storage (baseline) as well as on days 11, 22, 31, 38 and 43 for the non-irradiated RBC and on days 2, 6, 8, 13 and 15 for the γ-irradiated RBC.The following quality parameters were analyzed: potassium, hemolysis rate, ATP concentration and glucose/lactate concentration. For both study arms, irradiated and non-irradiated, our data demonstrates that although the hemolysis rate increases over time, it does not approach the limit value of 0.8%, even at the end of the shelf life. The same applies to the potassium release in non-irradiated RBCC: the concentration increases over time but does not exceed the limit value of 70 mmol/l. Only irradiated RBCC in DEHP/F and DINCH/F bags exceeded the potassium threshold on day 15. ATP levels were maintained at identical levels in all three blood bags. Moreover, metabolic rates did not differ among the blood bags.Hence, our results demonstrate that RBC in blood bags with the alternative plasticizer DINCH have a comparable quality over their shelf life to RBC in blood bag systems with DEHP (irradiated and non-irradiated). Nevertheless, the manufacturer suggests that the shelf life of non-irradiated RBCC stored in blood bags containing DINCH should be limited to a maximum of 28 days. Therefore, the longer shelf life of 42 days will be subject to further testing.The authors have no conflicts of interest to declare.

Dr.med.

Prof. Dr. med.

Assessing the Neutralizing Capacity of Early Pandemic Convalescent Plasma Against Emerging SARS-CoV-2 Variants

Bewertung der Neutralisierungskapazität von frühem Pandemie-Konvaleszenzplasma gegen neu auftretende SARS-CoV-2-Varianten

COVID-19 convalescent plasma (CCP) has shown promise in halting disease progression in COVID-19 patients. However, CCP products are often underutilized and may be stored for extended periods before administration. The efficacy of these CCP products against emerging variants of SARS-CoV-2 that arise later in the pandemic is a topic of concern. Aims: In this study, we investigated the neutralizing capacity of plasma collected from non-vaccinated donors during the early stages of the pandemic against subsequent emergent variants of SARS-CoV-2.Plasma donors, who had experienced COVID-19, were recruited. Levels of anti-SARS-CoV-2 antibodies (including Spike Trimer, Receptor Binding Domain (RBD), S1, S2, and nucleocapsid protein) were quantified using a multiplex serological assay (MULTICOV AB, NMI, Reutlingen, Germany). The neutralization capacity of RBD antibodies was assessed through an ACE2 binding inhibition assay. ACE2 binding inhibition was measured against wild type virus and variants of concern, including alpha, beta, gamma, delta, omicron BA.4, and omicron BA.5. Friedman test with Dunn's multiple comparisons was employed to compare ACE2 inhibition across different variants with the wild type.A total of 47 non-vaccinated CCP donors (25 female; 53%) with a median age of 47 years (range 40-60) were included in the analysis. CCP donations were obtained between January 2021 and June 2021. Compared to the wild type (18.2%; 12.9-21.1%), ACE2 binding inhibition was similar against the alpha (17.7%; 13.7-23.4%) and delta (16.1%; 13.2- 18.5%) variants (p&gt;0.05). However, ACE2 binding inhibition was significantly lower than that of the wild type against the beta (12.5%; 9.53-15.4%), gamma (10.1%; 6.41-13%), omicron BA.4 (5.22%; 1.99-6.92%), and omicron BA.5 (6.46%; 2.75-8.76%) variants (p&lt;0.05).Our findings indicate a potential decrease in the neutralizing efficacy of antibodies present in convalescent plasma from non-vaccinated donors against newly emerging SARS-CoV-2 variants. This emphasizes the critical need to evaluate the neutralization potential of therapeutic products against prevalent variants of SARS-CoV-2 before their clinical application, ensuring optimal clinical effectiveness.keine

Prof.

Validation of a single-tube flow cytometric assay for reliable quantification of residual cells in fresh-frozen plasma for routine use

Validierung einer Routinemethode in der Qualitätskontrolle zur zuverlässigen Quantifizierung von Restzellen in gefrorenem Frischplasma aus einem Ansatz

In our quality control of blood products, the residual cells in fresh-frozen plasma (FFP) are determined by three different methods. For routine measurement an efficient and accurate method to detect small numbers of residual leucocytes (rWBC), erythrocytes (rRBC) and platelets (rPLT) in a single-type assay is desirable. With the validation of the BD™ Plasma Count Kit, we have succeeded in establishing a flow cytometric measurement on the BD FACSLyric™, allowing simultaneous quantification.The BD™ Plasma Count Kit (PC) was validated on the highly sensitive BD FACSLyric™ system using the BD FACSuite™ v1.5 software for determination of the absolute cell counts of rWBC, rRBC and rPLT in FFP. With this kit all three cell types are quantified by flow cytometry in a single tube with the use of defined counting beads. Validation of the specificity, stability, linearity and repeatability was performed. In absence of commercially available system controls, whole blood controls from in-house production were established. A quantification of residual cells in plasma was done in direct comparison with the existing methods (flow cytometry for rWBC, microscopy for rRBC, and impedance measurement via Sysmex for rPLT).Specificity and recovery were demonstrated by spiking a defined numbers of cells in FFP. Furthermore, linearity was verified over a range of values relevant for routine use. The results of the inter- and intra-assay precision are consistent with the expected outcomes. Preanalytical procedures revealed that plasma samples can be stored at RT for up to 36h after initial collection. The validation demonstrated that 24 samples could be analysed in a single run. In addition, a comparative measurement of the routine methods with the Plasma Count was successfully performed. The difference of both measurements from mean did not exceed 1WBC/µl (LD plasma), 10 WBC/µl (NDL plasma), 550 RBC/µl and 4500 PLT/µl regarding testing individual samples.Our data show that the PC assay is suitable for quality control of plasma after production according to the German guidelines. The use of this assay is expected to increase efficiency and sample throughput. In addition, a parallel testing of the existing methods for residual cell counting and the initial data collected in the routine with the plasma count assay is planned.no conflict of interest

PD Dr. rer. nat.

Prof. Dr.

Lyophilized human platelet lysate from platelet concentrates for cell biology research and manufacturing of cell therapy products

Lyophilisiertes humanes Plättchenlysat aus Thrombozytenkonzentraten für die zellbiologische Forschung und die Herstellung von Zelltherapieprodukten

A significant number of platelet concentrates (PCs) is discarded daily due to limited shelf life. Human platelet lysate (HPL), derived from expired PCs, can serve as an ethical and sustainable alternative to fetal calf serum in biomedical research. We developed a method to produce HPL under GMP conditions for basic research and cell-based therapeutics. We follow the overall aim to enhance the applicability of HPL by lyophilization (L-HPL) leading to increased storage temperature and shelf life.Four pooled PCs, consisting of cell material from four donors each, were lysed by successive freezing and thawing cycles. The cell debris was separated by centrifugation and the supernatant was lyophilized. We compared HPL and L-HPL regarding their quality parameters pH, total protein, osmolality, sodium, potassium and chloride concentration and analyzed the concentrations of 13 growth factors (e.g. TGF-ß1, VEGF, bFGF). Additionally, we determined the cell yield and proliferation capacity of human mesenchymal stem cells (hMSCs) following expansion in cell culture media containing FCS, HPL and reconstituted L-HPL as well as the potential of hMSCs for adipogenic, chondrogenic and osteogenic differentiation following expansion.The quality parameters pH, total protein, osmolality, sodium, potassium and chloride concentration and growth factor concentrations are comparable between HPL and reconstituted L-HPL. Cell yield and proliferation capacity of hMSCs was significantly enhanced following culture in media containing HPL or reconstituted L-HPL if compared to cells cultured in FCS containing medium. Significant differences between hMSCs cultured in media containing HPL or reconstituted L-HPL in terms of proliferation capacity and differentiation potential were not detected (figure 1).We successfully developed a GMP-compliant method to produce well-applicable lyophilized HPL from expired PCs. The comparison of L-HPL with HPL revealed comparable quality parameters and growth factor concentrations, demonstrating the viability of L-HPL as a cell culture substitute. Notably, culture in media containing HPL or L-HPL proved increased cell yield, offering a more efficient and economical approach in comparison to FCS.none

New extendet-release oxygen carrier enables sustained oxygen supply for organ preservation

Neuer Sauerstoffträger mit verlängerter Freisetzung ermöglicht anhaltende Sauerstoffversorgung zur Organerhaltung

Organ damage due to hypoxia is a well-known problem, not only in emergency medicine, but also during surgical procedures when blood flow is interrupted. Due to their physical properties, previous formulations of our perfluorocarbon-based artificial oxygen carriers (LENOX) were not able to release O2 over a prolonged period of time without recharging at the lung. This work presents a break-through refinement of LENOX that now allows for sustained oxygen supply despite interrupted blood flow.Physicochemical properties and biocompatibility of the new extended-release oxygen carrier (E-ROC) in the cardioplegic solution Custodiol were tested. A basic characterization of LENOX in Custodiol was carried out with regard to particle size, oxygen release and viscosity. To determine their sustained oxygen release, time-dependent oxygen release measurements of preoxygenated E-ROC were carried out with the PreSens system in hypoxic media inside a hypoxia work station without any cells and in the presence of hypoxic (1 % O2) cardiomyocites (HL-1 cells). HL-1 cells were oxygenated with preoxygenated E-ROC in Custodiol and compared to pure Custodiol without any oxygen carriers and LENOX in Custodiol over a period of 4 h. HIF-1 α via Western blot, ROS production, cell viability, lactate and troponin release were determined as markers for cell status.The physical release of oxygen from E-ROC was more than twice as long as compared to LENOX loaded with the same amount of oxygen. In contrast to pure Custodiol, only E-ROC oxygenated hypoxic cells adequately and was able to supply the cells with sufficient oxygen for at least 4 h. When analyzing the ROS production, no increase compared to pure Custodiol control was determined. Importantly, the cell viability was not affected by the presence of E-ROC.With E-ROC we now can provide carrier fluid that provides sustained oxygen supply after singular charging, whereby the amount of oxygen released is sufficient to fuel cellular metabolism and the presence of the product had no negative effect on cells. This opens up a complete new field of application for artificial oxygen carriers in, for example, organ preservation without active perfusion or support during surgical procedures.The lecithin modified nanoscale oxygen carrier (LENOX) is registered as an invention at European patent office with the application number EP 22193221.3, filed on Aug. 31st, 2022.

Dip.Ing. (FH)

PD Dr.

Does the software update Trima 7 have an impact on cell content in the LRS chamber?

Hat das Software update Trima 7 Auswirkungen auf den Zellgehalt in der LRS Kammer?

Human cells of healthy donors are a limited source for research and important for studying immune cell functions or biomarker identifications. Platelet collection by apheresis includes a leukocyte reduction system (LRS) to reduce immune competent cells. The LRS chamber is enriched with white blood cells and widely used as a source for research use. For platelet collection with Trima Accel® automated blood collection system, the software update to version 7 with a new algorithm may have an impact on leukocyte content and cell composition in the LRS chamber.Platelet concentrates were obtained from healthy donors by apheresis with Trima Accel®, Terumo BCT using software versions 6 (v6) and 7 (v7). Cell collection was done either in autologous plasma (University Hospital Regensburg) or in additive solution (AS v7) T-PAS+ or Intersol (externally supplied). The LRS chamber was disconnected from the set system after apheresis and the cells were transferred to a tube. The volume was identified by pipetting. Cell concentration and leukocyte differentiation was done on an automated analyzer (Sysmex XN 550, Germany). Median values are shown in the text.The aim of our study was to compare cell content in the LRS of Trima v6 to v7 and to consider the impact of collecting platelets in plasma versus AS. The volume with plasma v6 was 8.25 mL (n=16) as compared to plasma v7 with 8.20 mL (n=13) and AS v7 with 3.0 mL (n=14). WBC concentrations in plasma v6, plasma v7 and AS v7 were 113.95 x 103/µL, 157.75 x 103/µL and 64 x 103/µL, respectively. Erythrocytes and platelets remained comparable with 6.20 x 106/µL and 1.26 x 106/µL in plasma v6, 6.25 x 106/µL and 1.07 x 106/µL in plasma v7 and 7.50 x 106/µL and 1.17 x 106/µL in AS v7. Leukocyte composition was 2.6%, 2.4% and 8.5% neutrophils, 74.0%, 71.3% and 66.7% lymphocytes, and 22.6%, 23.4% and 23.6% monocytes in plasma v6, plasma v7 and AS v7 respectively.The software adjustment of Trima Accel to v7 has no relevant impact on cell content and leukocyte composition in the LRS chamber produced by apheresis with plasma as cell suspension medium. However, when obtaining platelets in additive solution with Trima v7, the rinsing process leads to a clear volume reduction in the LRS and decreased absolute cell numbers. Additionally, the content of neutrophils was slightly increased. Thus, if high cell numbers are required LRS obtained from plateletpheresis with plasma may be preferred.There is no conflict of interest.

Characterization of artificial perfluorocarbon-based oxygen carriers under physiological blood flow conditions

Charakterisierung von künstlichen Perfluorcarbon-basierten Sauerstoffträgern unter physiologischen Blutfluss-Bedingungen

Artificial blood in the form of artificial oxygen carriers (AOCs) represents a promising alternative for erythrocyte concentrates in terms of oxygen transport capacity. The aim of this study was to investigate the stability and functionality of perfluorocarbon-based AOCs under shear stress by mimicking conditions of physiological blood flow utilizing a perfusion setup.An 8 % AOC emulsion in 0.9 % NaCl was synthezised by high-pressure homogenization and perfused over a period of up to 24 hours under normothermic conditions in a vessel-like perfusion setup using a peristaltic pump at 25 rpm. Samples were taken at 0, 1, 3, 6 and 24 hours of circulation in the perfusion setup and analyzed using dynamic light scattering, rheometry and respirometry. A control solution of AOCs incubated at static conditions, 37 °C and 5 % CO2 was characterized in the same way at the intervals indicated.Dynamic light scattering showed a slight increase in the mean particle diameter of the AOCs from 186 to 226 nm after a perfusion period of 24 h, while the static control solution showed an increase from 186 to 243 nm. The viscosity did not alter during 24 h perfusion and incubation, revealing values of 1 mPas (37 °C, shear rate: 333 s-1) for both perfused and statically-stored samples. The AOCs showed no change in oxygen capacity over a period of 24 h perfusion or incubation, with values between 2.1 and 2.5 µmol/mL. The oxygen capacity of NaCl control solution was considerably lower at all time points (1.1-1.4 µmol/mL), demonstrating that AOCs have an overall higher oxygen capacity (Fig. 1, n=3, mean with SD).The study revealed that the AOCs remained stable after 24 hours of perfusion under physiological flow conditions and retained their functionality in terms of oxygen transport capacity. Further research integrating a 3D-printed blood vessel into the perfusion system will aid in manufacturing perfluorocarbon nanoemulsions as artificial oxygen carriers for clinical use.Es besteht kein Interessenkonflikt.

Analysis of individual patient requirements for optimized serum eye drop production

Analyse des individuellen Patientenbedarfs für eine maßgeschneiderte Serumaugentropfenherstellung

Autologous serum eye drops (ASED) are an established treatment for various dry eye conditions. However, the amount of whole blood collected for ASED is often restricted, as patient-specific factors (e.g. Hb/Hct) have a limiting effect. Adjusting the serum volume per vial to the patient's actual needs could minimize the waste of residual serum and thus increase the size of each ASED batch. For this reason, we analyzed used ASED vials to determine the consumption of ASED more precisely.ASED are obtained from a patient-specific amount of whole blood. As a standard 1.5 mL serum is cryopreserved per vial (ATS12, ATS36, Heinz Meise GmbH, Germany). 11 batches of vials with residual serum were returned to us by 8 patients for consumption determination (n= 478, min 13/max 50; mean 43): each vial was weighed to calculate the difference to the average filling weight. The latter is based on data from 245 vials weighed directly after manufacturing. The calculations of the optimal ASED filling volume were carried out based on a new technology with filling volumes in the range from 0.1 to 2.0 mL that can be adjusted in 0.1 increments. Furthermore, the avoidable blood loss was calculated.245 ASED vials were analyzed directly after production containing an average serum filling weight of 1.56 g (min. 1.20 g/max. 1.70 g). 478 vials from 11 batches used by patients showed an average total consumption of 0.86 g serum per vial (min. 0.43 g/max. 1.24 g), which corresponds to an average proportion of 55 % (min. 28 %/max. 80 %). This results in an average loss of 45 % serum per vial (min. 20 %/max. 72 %) and an extrapolated loss of 182 ml whole blood (min. 52 ml/max. 317 ml) per collection for the patient. Adjusting the serum volume to the actual consumption to the nearest 0.1 mL would increase the absolute number of vials available by an average of 104 (min. 21/ max. 248), which corresponds to 6.7 % more vials per 0.1 mL of serum saved.An individualized filling quantity for ASEDs corresponds to the principle of fundamentally economical use of blood as a resource and minimizes serum loss. Significantly larger batches not only reduce the burden on patients due to a lower frequency of whole blood donation but can also reduce costs. Finally, it should be noted that appropriate validations must be carried out so that the shelf life does not represent a restriction on availability.The authors declare no conflicts of interest.

Phenotypic changes in cold stored platelet concentrates do not affect their ability to restore haemostasis

Phänotypische Veränderungen beeinflussen nicht die Fähigkeit zur Wiederherstellung der Hämostase in kalt gelagerten Thrombozyten

Platelet concentrates (PCs) are used to treat or prevent bleeding. The current standard room temperature (RT) storage is allowed only for 4-5 days due to high risk of bacterial contamination. We investigate the molecular changes in platelet concentrates stored at RT and 4°C and asses their performance in in vitro functional tests.Apheresis platelet concentrates were separated into 2 equivalent, GMP conforming bags kept at RT and the other at 4°C, under agitation. PCs were quality controlled according to clinical standard. The tests were performed using the PCs or PCs in a model of thrombocytopenia. Multicolour flow cytometry was used to assess platelet activation and metabolic status. Aggregometry was performed, as well as thromboelastography. A flow system mimicking the physiological flow conditions linked with real-time imaging was used to assess the clot forming ability, morphology and composition of the clots.All PCs were valid at both temperatures according to the quality control measures. Cold storage maintains higher platelet counts. The cold stored platelets show upregulated PS exposure, spontaneous degranulation, and slight increase of spontaneously aggregatory phenotype, but do not display lower viability. The platelet ability to degranulate upon stimulation is unaffected, the activation of integrins mediated through P2Y12 receptor is lowered, but increased upon PAR1 stimulation. Spontaneous aggregation is lowered, but below 15% for both temperatures. PC aggregation shows no significant difference when stimulated with collagen or ristocetin, but improved at arachidonic acid (AA), ADP, and TRAP-6 stimulation. The potential to restore haemostasis is improved in case of AA, collagen, ADP, and TRAP-6. Thromboelastography shows no change. Experiments performed in conditions of physiological flow show no comparable ability to form thrombi. In all tests the reactivity of PC or PC applied in a model of thrombocytopenia remained within the physiological values, with no indication of thrombotic phenotype.Cold-induced effects on platelet functions during storage time are significant on the molecular level, but do not impair the haemostatic functionality of cold stored platelet concentrates. Cold storage of platelet concentrates is a promising strategy to prolong the storage time, improve the platelet survival and reduce the risk of bacterial infection post transfusion, without incising the thrombotic risk.No conflict of interest to declare.

Lyophilization for long-term storage of perfluorocarbon-based artificial oxygen carriers

Lyophilisierung für die Langzeitlagerung von Perfluorcarbon-basierten künstlichen Sauerstoffträgern

Allogenic blood transfusions are indispensable in modern medicine, yet limited. Perfluorocarbon (PFC)-based artificial oxygen carriers present a promising alternative due to high oxygen capacity. Emulsification renders PFC compatible for intravenous use. For application, long-term storage stability is crucial. Despite colloidal instability in PFC/water emulsions, lyophilization offers a gentle way to dry sensitive products, ensuring a stable formulation for clinical use.The nanoemulsion consisted of a perfluorodecalin core and a mixed shell of albumin and lecithin (LENOX). Emulsification was carried out using a high-pressure homogenizer. After the synthesis of LENOX, different concentrations of trehalose were added as a cryoprotectant and the product was lyophilized, by using a protocol developed for a precursor formulation of LENOX. After a storage period of 24 h or 14 days the particles were reconstituted and subjected to physico-chemical characterization. Particle size was determined using dynamic light scattering, while viscosity was measured using a rheometer and oxygen capacity was measured using the Oroboros O2k respirometer.Particle size measurements 24 h post-lyophilization revealed no significant increase compared to non-lyophilized LENOX stored at 4 °C for the same duration (control emulsion). The particles of the control emulsion exhibited significant growth during the 14 days of storage at 4 °C, unlike the lyophilized particles. After 14 days, the particles of the control emulsion were significantly larger than the lyophilized particles. The rheological analysis indicated that the lyophilization did not affect emulsion viscosity. Furthermore, the determination of oxygen capacity showed no loss of functionality in the lyophilized particles after 14 days of storage compared to freshly synthesized LENOX and to the control emulsion.The data indicate that lyophilization improved the stability of LENOX compared to the control emulsion, as evidenced by the absence of particle growth and viscosity changes. Additionally, LENOX maintain their functionality post-lyophilization. Thus, lyophilization represents a promising storage option for the artificial oxygen carrier enabling long-term storage required for a clinical application.Some of the authors are named as inventors in the patent of the lecithin modified nanoscale oxygen carrier (LENOX) with the application number EP 22193221.3, filed on Aug. 31st, 2022, that was used for this work.

Establishment of ex-vivo normothermic heart perfusion with perfluorocarbon-based artificial oxygen carriers

Etablierung einer ex-vivo normothermen Herzperfusion mit Perfluorocarbon-basierten künstlichen Sauerstoffträgern

In heart transplantation, normothermic machine-perfusion (NT-MP) is a new tool to reduce time of ischemia; however warm perfusion requires red blood cells. Perfluorodecalin-based albumin-derived artificial oxygen carriers (A-AOC) have emerged as an universal alternative for erythrocytes.1 An in vivo study has demonstrated the exceptional biocompatibility of A-AOCs when administered intravenously.2 This project aimed to set up a physiological model for heart NT-MP in which A-AOCs can be implemented as blood substitutes.NT-MP was established as physiological model for testing the functionality of A‑AOCs in an isolated perfused porcine heart. Hemodynamic and biochemical investigations of the preservation fluids were studied by blood gas analyzer and photometry (respons 920).Preliminary experiments in the established perfusion apparatus showed that the perfusion with a preservation solution was able to maintain a contracting heart for at least three hours. Changes in lactate and glucose levels in the perfusion medium were monitored as metabolic markers. Cellular damage was determined by time-resolved measurements of released lactate dehydrogenase and troponin-I into the perfusate.Once the experimental setup for perfusing porcine hearts is successfully established, we will explore the potential of A-AOCs to reduce reperfusion-associated acute myocardial infarction (repAMI) during ex vivo heart perfusion. Our group previously demonstrated the successful preservation of isolated rat hearts.3 Hence, decreased repAMI injury is anticipated for NT-MP with A-AOCs.1 Ferenz, O. Karaman, S. B. Shah in Nanotechnology for Hematology, Blood Transfusion, and Artificial Blood, Elsevier, 2022, pp. 397–427. 2 Wrobeln, J. Laudien, C. Groß-Heitfeld, J. Linders, C. Mayer, B. Wilde, T. Knoll, D. Naglav, M. Kirsch, K. B. Ferenz, European Journal of Pharmaceutics and Biopharmaceutics 2017, 115 , 52-64. 3 Wrobeln, K. D. Schlüter, J. Linders, M. Zähres, C. Mayer, M. Kirsch, K. B. Ferenz, Artificial cells, nanomedicine, and biotechnology 2017, 45, 723.No conflicts of interest.

Posterausstellung 10
Blood Components

Appointment

Programme

Posterausstellung 10Blood Components

Appointment

Programme

Posterausstellung 10
Blood Components