Integration of ζ-deficient CARs into the CD3ζ gene conveys potent cytotoxicity in T and NK cells.

ABSTRACT: Chimeric antigen receptor (CAR)-redirected immune cells hold significant therapeutic potential for oncology, autoimmune diseases, transplant medicine, and infections. All approved CAR-T therapies rely on personalized manufacturing using undirected viral gene transfer, which results in nonphysiological regulation of CAR-signaling and limits their accessibility due to logistical challenges, high costs and biosafety requirements. Random gene transfer modalities pose a risk of malignant transformation by insertional mutagenesis. Here, we propose a novel approach utilizing CRISPR-Cas gene editing to redirect T cells and natural killer (NK) cells with CARs. By transferring shorter, truncated CAR-transgenes lacking a main activation domain into the human CD3ζ (CD247) gene, functional CAR fusion-genes are generated that exploit the endogenous CD3ζ gene as the CAR's activation domain. Repurposing this T/NK-cell lineage gene facilitated physiological regulation of CAR expression and redirection of various immune cell types, including conventional T cells, TCRγ/δ T cells, regulatory T cells, and NK cells. In T cells, CD3ζ in-frame fusion eliminated TCR surface expression, reducing the risk of graft-versus-host disease in allogeneic off-the-shelf settings. CD3ζ-CD19-CAR-T cells exhibited comparable leukemia control to TCRα chain constant (TRAC)-replaced and lentivirus-transduced CAR-T cells in vivo. Tuning of CD3ζ-CAR-expression levels significantly improved the in vivo efficacy. Notably, CD3ζ gene editing enabled redirection of NK cells without impairing their canonical functions. Thus, CD3ζ gene editing is a promising platform for the development of allogeneic off-the-shelf cell therapies using redirected killer lymphocytes.

Positive Long-Term Outcome of Kidney Allocation via Acceptable Mismatch Program in Highly Sensitized Patients.

Introduction: Eurotransplant established the acceptable mismatch (AM) program to facilitate timely kidney transplantations of highly sensitized patients, but long-term granular clinical and immunological outcomes regarding overall graft survival and de novo DSA (dnDSA) formation are still intensively researched. The right choice of induction therapy in patients with differing immunological risk is not conclusively determined, as well as the impact of human leukocyte antigen (HLA) epitope matching on dnDSA formation. Methods: This monocentric, retrospective study analyzed 94 patients transplanted within the AM program between 2000 and 2019 compared to case-control matched cohorts of non- (PRA 0-5%; PRA-0) and intermediately sensitized (PRA 6-84%; PRA-6/84) patients transplanted through Eurotransplant Kidney Allocation System. Results: Estimated 10-year overall graft survival between the PRA-0 and AM cohorts was similar, whereas PRA-6/84 was significantly disadvantageous compared to PRA-0. Estimated 10-year incidence of antibody-mediated rejection rates was significantly lower in the PRA-0 group compared to AM and PRA-6/84 groups. Compared to the AM group, estimated incidence of de novo donor-specific antibody (dnDSA) was significantly lower in PRA-0 patients, with no differences between the AM and PRA-6/84 cohorts. The PRA-6/84 cohort was the only subgroup in which interleukin-2 receptor antagonist (IL2RA) induction was associated with longer overall graft survival, patient survival, and graft survival compared to depleting induction (ATG or OKT3). Broad HLA-A, -B, -DR mismatches (mmABDR) and HLA epitope mismatches determined by Eplets and PIRCHE-II were predictive for dnDSA formation in the total cohort, and the AM subgroup. Discussion: The high efforts expended on AM patients are justified to allow timely organ transplantation with acceptable risk profile and non-inferior outcomes. IL2RA induction in intermediately sensitized patients is associated with superior overall graft survival, patient survival, and graft survival compared to ATG/OKT3 induction, without negative effects on rejection episodes or dnDSA formation. In silico epitope matching might further help reduce dnDSA formation, particularly in high-risk AM patients.

Allografts: expanding the surgeon's armamentarium.

In Germany, bone allografts are widely used and their application in clinics has increased over the years. Successful use of allografts depends on many factors such as the procurement, processing, sterilization and the surgeon's surgical experience. Tissue banks have provided safe and sterile allografts for decades ranging from hard to soft tissue. Allografts are obtained from various tissues such as bone, tendon, amniotic membrane, meniscus and skin. An advantage of allografts is their wide applicability that has never been limited by indication restrictions thus providing a huge benefit for surgeon's. The use of the correct allograft in different indications is extremely important. Thereby surgeons have access to various allograft forms such as mineralized, demineralized, freeze-dried, paste, powder, chips strips and putty. The vast options of allografts allow surgeon's to use allografts in indications they deem fit. Currently, the application of allografts is at the discretion of the expert surgeon. However, regulations are often changed locally or internationally and may impact/limit allograft use to certain indications. Here, we report the different indications where our peracetic acid (PAA) sterilised bone allografts were used as well as general literature on bone allograft use in other indications.

Validation of Microbiological Testing of Tissue Preparations with Different Incubation Temperatures.

INTRODUCTION: The European Pharmacopoeia (Ph. Eur.) provides principles for microbiological testing of tissue preparations. According to the Ph. Eur., tests should be performed at different temperatures for detection of aerobic bacteria and fungi (20-25°C) vs. anaerobic bacteria (30-35°C). Semiautomated systems using blood culture bottles are already widely used and they are adequate for growth detection. Resin-containing bottles and the addition of penicillinase permit testing of culture media containing antibiotics. MATERIALS AND METHODS: At 3 temperatures (21, 30, and 35°C) cornea culture media with and without dextran (CM II and CM I) and thermal disinfected femoral head medium (FH) were spiked with the 6 reference strains recommended by the Ph. Eur. (additionally: Enterococcus faecalis, Staphylococcus epidermidis, and Cutibacterium acnes). Microbial growth was monitored with the BACTECTM FX unit or visually at 21°C. RESULTS: Growth for all strains was detected with each medium at all 3 temperatures, except for C. acnes at 21°C (all media) and 30°C with FH. C. acnes had the highest times to detection, requiring test durations of 14 days. Microbial growth was faster at 30 and 35°C compared to 21°C. CONCLUSION: The requirements according to the Ph. Eur. for a successful method suitability test could be fulfilled for the semiautomated blood culture bottle system with the BACTECTM FX unit for the media and microorganisms used. In the presented validation study 35°C was shown to be the incubation temperature with the fastest growth, of the majority of the test strains used, and complete detection within 14 days.

Algorithms for the Testing of Tissue Donors for Human Immunodeficiency Virus, Hepatitis B Virus, and Hepatitis C Virus.

BACKGROUND: Although transmission of pathogenic viruses through human tissue grafts is rare, it is still one of the most serious dreaded risks of transplantation. Therefore, in addition to the detailed medical and social history, a comprehensive serologic and molecular screening of the tissue donors for relevant viral markers for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) is necessary. In the case of reactive results in particular, clear decisions regarding follow-up testing and the criteria for tissue release must be made. METHODS: Based on the clinical relevance of the specific virus markers, the sensitivity of the serological and molecular biological methods used and the application of inactivation methods, algorithms for tissue release are suggested. RESULTS: Compliance with the preanalytical requirements and assessment of a possible hemodilution are mandatory requirements before testing the blood samples. While HIV testing follows defined algorithms, the procedures for HBV and HCV diagnostics are under discussion. Screening and decisions for HBV are often not as simple, e.g., due to cases of occult HBV infection, false-positive anti-HBc results, or early window period positive HBV NAT results. In the case of HCV diagnostics, modern therapies with direct-acting antivirals, which are often associated with successful treatment of the infection, should be included in the decision. CONCLUSION: In HBV and HCV testing, a high-sensitivity virus genome test should play a central role in diagnostics, especially in the case of equivocal serology, and it should be the basis for the decision to release the tissue. The proposed test algorithms and decisions are also based on current European recommendations and standards for safety and quality assurance in tissue and cell banking.

Comparison of Total Immunoglobulin G in Ante- and Postmortem Blood Samples from Tissue Donors.

BACKGROUND: A serology testing for infectious diseases (HIV, hepatitis B and C, syphilis) is mandatory in tissue donors. In many donors postmortem blood is the only sample available. Even though serological tests and nucleic acid amplification tests (NAT) used are validated for postmortem blood, a characterization of those blood samples is not yet established. We therefore investigated the total immunoglobulin G (IgG) content in postmortem blood of tissue donors and compared it to a corresponding antemortem blood sample. METHODS: Ante- and postmortem blood samples were obtained from 100 consecutive tissue donors. The total IgG of all samples was measured using an immune-turbidometric test on the AU 480 Chemistry Analyzer (Beckman Coulter). RESULTS: The mean total IgG concentration of antemortem blood samples from all 100 donors was 8.9 g/L ± 3.7 g/L (median 8.9 g/L, range 1.5 to 23.8 g/L). In 80 donors the IgG concentration in the antemortem blood sample was within the normal range with values ≥6 g/L (mean 10.0 g/L ± 3.3 g/L, median 9.3 g/L,). The total IgG concentration of the postmortem blood samples was lower with 7.2 g/L ± 3.2 g/L (median 6.7 g/L, range 0.6 to 18.2 g/L). The difference between the values of the antemortem and postmortem blood samples was 1.7 g/L ± 2.6 g/L (16.3%) (median 1.6 g/L, range -7.7 to 10.1 g/L). In 36 donors this difference was less than 10%, in 23 it was between 10 and 25%, in 33 between 26 and 50%, and in 8 over 50%. In 57 donors the total IgG in the postmortem blood sample was within the normal range with ≥6 g/L, in 53 of them also the value of the antemortem blood sample was within the normal range. No correlation for total IgG was found regarding the donor characteristics (age, sex, disease) and the sample characteristics (hemolysis, postmortem time). CONCLUSION: Total IgG values in antemortem samples were below the lower limit of 6 g/L in 20% of the cases. Total IgG was significantly lower in the postmortem samples compared to the antemortem samples, while 57% were still above the lower limit. No correlation with the postmortem time could be found. This lowered IgG levels should be payed attention to when using postmortem blood for infectious serology testing. Additional NAT testing should be considered.

[A clinical radiological score for femoral head grafts : Establishment of the Tabea FK score to ensure the quality of human femoral head grafts]. / Ein klinisch-radiologischer Score für Femurkopftransplantate : Etablierung des Tabea-FK-Scores zur Sicherung der Qualität humaner Femurkopftransplantate.

INTRODUCTION: Transplantation of cancellous tissue from human femoral heads (FK) is an established method in the reconstruction of bony defects in orthopedic and trauma surgery. Standardized rating systems with respect to the morphological quality of this tissue are not available. MATERIALS AND METHODS: In 91/105 patients who had been a regular, clinically-indicated surgery (arthroplasty of the hip joint) the respective femoral head (FK) was taken under standardized conditions. Using a checklist defined clinical and radiological criteria of FK are judged in terms of their quality (cysts, necrosis, calcification, deformities, osteoporosis) and divided by the Tabea FK score into three classes (best/middle/poor quality). This was followed by a blinded repeated scoring, now as macroscopic assessment of three sawed layers from the same femoral head. The femoral heads are examined by peripheral quantitative computed tomography (pQCT) and a standardized histological examination of the bony tissue. We evaluated the accordance of the Tabea FK score with complementary assessments by calculation of sensitivity and specificity. RESULTS: Femoral heads from 91/105 patients (ages: 68.4 ± 9.9 , n = 60 women, n = 31 men) were explanted and included in the study. The correlation between the primary radiologic clinical score (Tabea FK score) and the macroscopic second review of the sawn FK with respect to middle/best and poor/middle quality was classified as good (sensitivity 77% and 81%, respectively; specificity 76% and 84%, respectively). The correlation of histology and macroscopic second review was worse and in relation to discrimination of middle/best and poor/middle quality had a sensitivity of 85% and 54%, respectively, and a specificity of 66% and 97%, respectively. The pQCT showed a sensitivity of 82% only in discrimination of middle/best, while sensitivity in discrimination of poor/middle and poor/middle + best, respectively, was <10%. DISCUSSION: The corresponding correlation between the primary and the second clinical score was evaluated as good. This emphasizes the long-standing skills of operationally active orthopedic surgeons to classify the quality of cancellous bone correctly already on the basis of X­ray images and intraoperative findings. In this respect, the introduction of the Tabea FK score as a quality assurance tool in the routines of bone banks can be recommended.

Pooling, room temperature, and extended storage time increase the release of adult-specific biologic response modifiers in platelet concentrates: a hidden transfusion risk for neonates?

BACKGROUND: Adult donor platelets (PLTs) are frequently transfused to prevent or stop bleeding in neonates with thrombocytopenia. There is evidence for PLT transfusion-related morbidity and mortality, leading to the hypothesis on immunomodulatory effects of transfusing adult PLTs into neonates. Candidate factors are biologic response modifiers (BRMs) that are expressed at higher rates in adult than in neonatal PLTs. This study investigated whether storage conditions or preparation methods impact on the release of those differentially expressed BRMs. STUDY DESIGN AND METHODS: Pooled PLT concentrates (PCs) and apheresis PCs (APCs) were stored under agitation for up to 7 days at room temperature (RT) or at 2 to 8°C. The BRMs CCL5/RANTES, TGFß1, TSP1, and DKK1 were measured in PCs' supernatant, lysate, and corresponding plasma. PLT function was assessed by light transmission aggregometry. RESULTS: Concerning the preparation method, higher concentrations of DKK1 were found in pooled PCs compared to APCs. In supernatants, the concentrations of CCL5, TGFß1, TSP1, and DKK1 significantly increased, both over standard (≤4 days) and over extended storage times (7 days). Each of the four BRMs showed an up to twofold increase in concentration after storage at RT compared to cold storage (CS). There was no difference in the aggregation capacity. CONCLUSION: This analysis shows that the release of adult-specific BRMs during storage is lowest in short- and CS APCs. Our study points to strategies for reducing the exposure of sick neonates to BRMs that can be specifically associated to PLT transfusion-related morbidity.

Donor selection in a pediatric stem cell transplantation cohort using PIRCHE and HLA-DPB1 typing.

BACKGROUND: New strategies to optimize donor selection for hematopoietic stem cell transplantation (HSCT) have mainly been evaluated in adults, but the disease spectrum requiring HSCT differs significantly in children and has consequences for the risk of complications, such as graft-versus-host disease (GvHD). PROCEDURES: Here we evaluated whether HLA-DPB1 and Predicted Indirectly ReCognizable HLA-Epitope (PIRCHE) matching can improve donor selection and minimize risks specific for a pediatric cohort undergoing HSCT in Berlin between 2014 and 2016. RESULTS: The percentage of HLA-DPB1-mismatched HSCT in the pediatric cohort was in line with the general distribution among matched unrelated donor HSCT. Nonpermissive HLA-DPB1 mismatches were not associated with a higher incidence of GvHD, but the incidence of relapse was higher in patients undergoing HSCT from HLA-DPB1-matched transplantations. High PIRCHE-I scores were associated with a significantly higher risk for developing GvHD in patients undergoing HSCT from nine of ten matched unrelated donors. This finding persisted after including HLA-DPB1 into the PIRCHE analysis. CONCLUSIONS: Implementing PIRCHE typing in the donor selection process for HSCT in children could particularly benefit children with nonmalignant diseases and support further validation of PIRCHE-based donor selection in a larger number of children treated at different sites.

Influence of thermodisinfection on microstructure of human femoral heads: duration of heat exposition and compressive strength.

Allogeneic bone derived from living donors being necessary to match demand for bone transplantation and thermodisinfection of femoral heads is an established sterilization method. During the thermodisinfection the peripheral bone is exposed to maximum 86 °C for 94 min providing 82.5 °C within the center of the femoral head for at least 15 min. This study examined the compression force of the central and representative peripheral regions of native and thermodisinfected human femoral heads to observe wether different duration and intensity of heat exposure might alter mechanic behaviour. Slices from the equatorial region of human femoral heads were taken from each 14 native and thermodisinfected human femoral heads. The central area revealed a significantly higher compression force for native (p ≤ 0.001) and for thermodisinfected bone (p = 0.002 and p = 0.005) compared with peripheral regions since no relevant differences were found between the peripheral and intermediate areas themselves. A small reduction of compression force for thermodisinfected bone was shown since this did not appear significant due to the small number of specimens. The heat exposure did not alter the pre-existing anatomical changes of the microarchitecture of the native femoral heads from the center towards the peripheral regions. The heterogeneity of microstructure of the femoral head might be of interest concerning clinical applications of bone grafts since the difference between native and thermodisinfected bone appears moderate as shown previously. The different quantity of heat exposure did not reveal any significant influence on compression force which might enable thermodisinfection of preformed bone pieces for surgical indications.

Riboflavin: The Health Benefits of a Forgotten Natural Vitamin.

Riboflavin (RF) is a water-soluble member of the B-vitamin family. Sufficient dietary and supplemental RF intake appears to have a protective effect on various medical conditions such as sepsis, ischemia etc., while it also contributes to the reduction in the risk of some forms of cancer in humans. These biological effects of RF have been widely studied for their anti-oxidant, anti-aging, anti-inflammatory, anti-nociceptive and anti-cancer properties. Moreover, the combination of RF and other compounds or drugs can have a wide variety of effects and protective properties, and diminish the toxic effect of drugs in several treatments. Research has been done in order to review the latest findings about the link between RF and different clinical aberrations. Since further studies have been published in this field, it is appropriate to consider a re-evaluation of the importance of RF in terms of its beneficial properties.

Determination of Methemoglobin in Hemoglobin Submicron Particles Using NMR Relaxometry.

Methemoglobin (MetHb) is a hemoglobin (Hb) derivative with the heme iron in ferric state (Fe3+), unable to deliver oxygen. Quantification of methemoglobin is a very important diagnostic parameter in hypoxia. Recently, novel hemoglobin microparticles (Hb-MP) with a narrow size distribution around 700 nm, consisting of cross-linked Hb were proposed as artificial oxygen carriers. The cross-linking of Hb by glutaraldehyde (GA) generates a certain amount of MetHb. Due to the strong light scattering, quantitative determination of MetHb in Hb-MP suspensions by common spectrophotometry is not possible. Here, we demonstrate that 1H2O NMR relaxometry is a perfect tool for direct measurement of total Hb and MetHb concentrations in Hb-MP samples. The longitudinal relaxation rate 1/T1 shows a linear increase with increasing MetHb concentration, whereas the transverse relaxation rate 1/T2 linearly increases with the total Hb concentration. In both linear regressions the determination coefficient (R2) is higher than 0.99. The method does not require time-consuming pretreatment or digestion of the particles and is not impaired by light scattering. Therefore, it can be established as the method of choice for the quality control of Hb-MP and similar hemoglobin-based oxygen carriers in the future.

Transfusion of red blood cells does not impact progression-free and overall survival after surgery for ovarian cancer.

BACKGROUND: Allogeneic red blood cells (RBCs) have the potential to impact the immunosurveillance of the recipient and may therefore increase the risk of recurrence after cancer surgery. In this article the relationship between perioperative RBC transfusion and the risk of recurrence after ovarian cancer surgery is examined. STUDY DESIGN AND METHODS: This is a retrospective cohort analysis of a prospective database of patients who underwent surgery due to primary ovarian cancer between 2006 and 2014 and who had no residual disease after surgery. Patients who did and did not receive perioperative RBC transfusion were compared. The primary endpoint was progression-free survival (PFS). Propensity score matching (PSM) and Cox proportional hazards regression (CPH) was used to control for between-group differences of prognostic determinants. RESULTS: A total of 529 patients with a median follow-up of 51.4 months (95% CI, 46.1-56.5) were eligible for analysis. Of those, 408 patients (77.1%) received allogeneic, leukoreduced RBCs with a median of 4 units (IQR, 2-6) per patient. There was a strong selection bias of prognostic determinants between patients with and without transfusion. In unadjusted analysis, transfusion of RBCs was associated with an increased risk of cancer recurrence (hazard ratio [HR] of PFS 2.71 [95% CI, 1.94-3.77], p < 0.001). After bias reduction, transfusion of RBCs was no longer associated with an increased risk of cancer recurrence, neither in PSM-adjusted (HR 1.03 [95% CI, 0.59-1.80], p = 0.91), nor in multivariable CPH-adjusted analysis (HR 1.26 [95% CI, 0.85-1.86], p = 0.23). CONCLUSION: Perioperative transfusion of RBCs did not increase the risk of recurrence after ovarian cancer surgery.

Duration of storage influences the hemoglobin rising effect of red blood cells in patients undergoing major abdominal surgery.

BACKGROUND: After transfusion of senescent red blood cells (RBCs) a considerable fraction is rapidly cleared from the recipients' circulation. Thus, transfusion of senescent RBCs may be less effective in terms of increasing hemoglobin concentration (cHb) after transfusion. STUDY DESIGN AND METHODS: Data were retrospectively obtained in patients who underwent major abdominal surgery between 2006 and 2012. Patients were eligible if they received RBCs during surgery and had at least two arterial blood gas analyses performed. The primary endpoint was the increase of recipients' cHb related to the transfusion of 1 unit of RBCs with respect to different storage periods. Four storage periods were defined according to the distribution of RBC storage of the study population. General estimating equation was used for calculation of the primary endpoint and to adjust for confounding variables. RESULTS: A total of 598 arterial blood gas samples from 120 patients, receiving 429 RBC units, were analyzed. Mean (±SD) RBC storage was 21 (±9) days. RBC storage duration and the increase in recipients' cHb were inversely and gradually related; that is, the older the RBCs, the lower the increase in the recipients' cHb after transfusion (storage < 12 days, ΔcHb per unit RBCs +0.82 [95% confidence interval, 0.42-1.21] g/dL, p < 0.01; storage 12-20 days, +0.66 [0.46-0.86] g/dL, p < 0.01; storage 21-29 days, +0.56 [0.33-0.79] g/dL, p < 0.01; storage ≥30 days, +0.39 [0.07 to 0.71] g/dL, p = 0.02). CONCLUSION: Transfusion of senescent RBCs increased cHb less effectively than transfusion of fresher RBCs.

Preclinical In Vitro Safety Investigations of Submicron Sized Hemoglobin Based Oxygen Carrier HbMP-700.

Hemoglobin-based oxygen carriers (HBOCs) are being developed as oxygen and plasma volume-expanding therapeutics though their potential to promote oxidative tissue injury and nitric oxide (NO) scavenging combined with vasoconstriction has raised safety concerns. Therefore, we focused on these aspects during preclinical studies performed with the recently introduced hemoglobin microparticles (HbMP-700). Besides oxidative stress, we investigated possible vasoconstrictory influence of HBOCs as well as genetic toxicity. The novel developed HbMP-700 presented here provides a high oxygen affinity which prevents premature oxygen oversupply and avoids vasoconstriction of small blood vessels in vitro. The size of these particles is 700 nm (larger than 100 nm and smaller than 1000 nm) in order to prevent penetration through the blood vessel's endothelial gaps, NO-scavenging, and to avoid phagocytosis of large particles. We expect that the HbMP-700 meets the sophisticated requirements as a universal blood substitute.

Evaluation of the New Lateral Flow Card MDmulticard® Basic Extended Phenotype in Routine Clinical Practice.

BACKGROUND: Transfusion emergencies and critical situations require specifically designed devices to simplify and optimize the standard procedures. In addition, matching antigens over and above ABO-Rh-K would be beneficial. METHODS: Routine blood samples were collected in four immunohematology centers and tested with the new MDmulticard Basic Extended Phenotype for the simultaneous detection of the Duffy, Kidd, and Ss antigens, according to the principle of the lateral flow. Results were compared with those obtained using routine serology methods. Discrepancies were analyzed by molecular techniques/genotyping. RESULTS: 310 samples were tested (167 donors; 75 patients; 28 subjects with positive direct antiglobulin test (DAT); 15 newborns; 25 previously transfused patients). The 285 samples with non-mixed-field reaction yielded 1,710 antigen results with 8 discrepancies (0.47%) six of which in DAT-positive subjects: three false-positive (Fya) for MDmulticard, and two false-positive (Fya) plus three false-negative (Fyb) for the reference methods (MDmulticard PPA for donors/patients/newborns: 99.82%; negative percent agreement: 100%; sensitivity: 100%; specificity: 99.39%, positive predictive value: 99.75%; negative predictive value: 100%). The MDmulticard detected mixed-field in 15 antigen reactions from 13 transfused patients, undetected by the comparative method, with the opposite result in 8 antigens (5 patients). CONCLUSION: The MDmulticard Basic Extended Phenotype met the criteria prescribed for the testing of donor, patient, DAT-positive, and newborn samples in transfusion laboratory routine.

Comparative Analysis of Different Platelet Lysates and Platelet Rich Preparations to Stimulate Tendon Cell Biology: An In Vitro Study.

The poor healing potential of tendons is still a clinical problem, and the use of Platelet Rich Plasma (PRP) was hypothesized to stimulate healing. As the efficacy of PRPs remains unproven, platelet lysate (PL) could be an alternative with its main advantages of storage and characterization before use. Five different blood products were prepared from 16 male donors: human serum, two PRPs (Arthrex, (PRP-ACP); RegenLab (PRP-BCT)), platelet concentrate (apheresis, PC), and PL (freezing-thawing destruction of PC). Additionally, ten commercial allogenic PLs (AlloPL) from pooled donors were tested. The highest concentration of most growth factors was found in AlloPL, whereas the release of growth factors lasted longer in the other products. PRP-ACP, PRP-BCT, and PC significantly increased cell viability of human tenocyte-like cells, whereas PC and AlloPL increased Col1A1 expression and PRP-BCT increased Col3A1 expression. MMP-1, IL-1ß, and HGF expression was significantly increased and Scleraxis expression decreased by most blood products. COX1 expression significantly decreased by PC and AlloPL. No clear positive effects on tendon cell biology could be shown, which might partially explain the weak outcome results in clinical practice. Pooled PL seemed to have the most beneficial effects and might be the future in using blood products for tendon tissue regeneration.

Implementation of the Single European Code in a Multi-Tissue Bank.

INTRODUCTION: The traceability of tissue and cells transplants is important to ensure a high level of safety for the recipients. With the final introduction of the Single European Code (SEC) in April 2017 in the EU a consistent system among all member states became mandatory. METHODS: The regulations for the SEC on EU and national level were evaluated. An overview on the different parts of the SEC with detailed explanations is given. Our own experiences with the implementation of the SEC in our multi-tissue bank are reported in addition. RESULTS: The implementation of the SEC in our multi-tissue bank could be successfully realized. However, it revealed a number of difficulties, especially the sterile labeling of certain tissue transplants and the complex update of the existing database. CONCLUSION: The introduction of the SEC has made a contribution to the safety of recipients of tissue and cells transplants through a system of comprehensive and transparent traceability.