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

Three different pathways of IgM-antibody-dependent hemolysis are mainly regulated by complement

Antibodies to red blood cells (RBCs) may hemolyze erythrocytes via Fc-mediated phagocytosis or complement-dependent. Complement activation on RBCs can be detected by C3d-direct antiglobulin test (DAT), which is the only test in immune hematology that directly targets complement. However, a positive DAT with anti-C3d cannot distinguish between C3b-mediated extravascular hemolysis, C5b-C9-mediated intravascular hemolysis and C5b-C8-mediated eryptosis. Furthermore, DAT is not suitable to estimate the strength of hemolysis. Autoimmune hemolytic anemia (AIHA) is a rare disease that is caused by autoantibodies to red blood cells that is divided in warm AIHA and in cold agglutinin disease (CAD). The causative antibodies in CAD and sometimes in warm AIHA are from the IgM class. Depending on strength of complement activation they can induce extravascular hemolysis, intravascular hemolysis and eryptosis. We studied the three types of hemolysis by use of sera from patients with CAD under various conditions. We found that additionally to the routinely applied C3d-DAT, indirect tests for complement activity (free hemoglobin and Annexin V-binding to phosphatidylserine-exposing RBCs) should be used to determine the portion of extravascular, intravascular and eryptotic hemolysis. Eryptotic hemolysis may have a significant share in clinical relevant CAD or IgM warm AIHA, which should be considered for successful treatment

Doxorubicin-Loaded Human Serum Albumin Submicron Particles: Preparation, Characterization and In Vitro Cellular Uptake

Doxorubicin (DOX) is an effective anthracycline antibiotic drug which is commonly used in a broad range cancer therapy. However, due to dose depending side effects and toxicity to non-cancerous tissues, its clinical applications are restricted. To overcome these limitations, human serum albumin (HSA) has been investigated as a biocompatible drug delivery vehicle. In this study, human serum albumin submicron particles (HSA-MPs) were fabricated by using the Co-precipitation-Crosslinking-Dissolution technique (CCD technique) and DOX was loaded into the protein particles by absorption. DOX-HSA-MPs showed uniform peanut-like shape, submicron size and negative zeta-potential (-13 mV). The DOX entrapment efficiency was 25% of the initial amount. The in vitro release in phosphate buffered saline pH 7.4 was less than 1% within 5 h. In contrast, up to 40% of the entrapped DOX was released in presence of a protein digesting enzyme mixture (Pronase®) within the same time. In addition, in vitro cytotoxicity and cellular uptake of DOX-HSA-MPs were evaluated using the lung carcinoma cell line A549. The results demonstrated that DOX-HSA-MPs reduced the cell metabolic activities after 72 h. Interestingly, DOX-HSA-MPs were taken up by A549 cells up to 98% and localized in the cell lysosomal compartment. This study suggests that DOX-HSA-MPs which was fabricated by CCD technique is seen as a promising biopolymer particle as well as a viable alternative for drug delivery application to use for cancer therapy

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

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 (Fy(a)) for MDmulticard, and two false-positive (Fy(a)) plus three false-negative (Fy(b)) 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

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

Adding a piece to the puzzle of Latin American blood donors and the potential risk of Trypanosoma cruzi transmission in Germany

Introduction: Chagas disease (CD) is caused by the Trypanosoma cruzi (T. cruzi) infection and has become a global health concern due to population mobility, as well as non-vectorial transmission routes. Several countries outside Latin America (LA) have reported transfusion-associated transmission, but equivalent studies in Germany are lacking. This study aims to collect first data on the risk of transfusion associated transmission as well as LA blood donors originating from CD endemic countries in Germany Materials and methods: A total of 305 blood donors who were assumed to be at risk for T. cruzi infection were retrospectively (267) as well as prospectively (38) selected at German blood donation sites in Bavaria and Berlin, and all retrospectively as well as 27 prospectively selected were serologically screened. Prospective study subjects additionally filled out a questionnaire. Results: All samples tested seronegative for T. cuzi specific antibodies. Prospectively enrolled study subjects all had high socio-economic status including good education. Knowledge regarding CD was limited but willingness to donate frequently was high. Blood donation rates from donors born in LA countries seem to increase from 2015. Discussion: Although no transfusion associated T. cruzi infection has been documented in Germany, it has likely already happened unnoticed, or will do in the near future. Performing risk-adapted serology-based blood donor screenings in Germany could avoid transfusion-associated transmission events as well as contribute to active case detection. Moreover, larger, and ongoing studies are needed to increase the evidence base as well as end the neglect of CD in Germany

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

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 degrees C. The BRMs CCL5/RANTES, TGF beta 1, 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, TGF beta 1, 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