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AMB Express Jun 2024Bacterial contamination is the most prevalent infectious complication of blood transfusion in the developed world. To mitigate this, several ultraviolet light-based...
Bacterial contamination is the most prevalent infectious complication of blood transfusion in the developed world. To mitigate this, several ultraviolet light-based pathogen reduction technologies (PRTs), some of which require photo-chemicals, have been developed to minimize infection transmission. Relative to UV light, visible 405-nm light is safer and has shown potential to be developed as a PRT for the in situ treatment of ex vivo human plasma and platelet concentrates, without the need for photo-chemicals. This study investigates the effect of 405-nm light on human plasma, with focus on the compatibility of antimicrobial light doses with essential plasma clotting factors. To determine an effective antimicrobial dose that is compatible with plasma, prebagged human plasma (up to 300 mL) was seeded with common microbial contaminants and treated with increasing doses of 405-nm light (16 mW cm; ≤ 403 J cm). Post-exposure plasma protein integrity was investigated using an AOPP assay, in vitro coagulation tests, and ELISA-based measurement of fibrinogen and Protein S. Microbial contamination in 300 mL prebagged human plasma was significantly reduced (P ≤ 0.05) after exposure to ≤ 288 J cm, with microbial loads reduced by > 96.2%. This dose did not significantly affect the plasma protein quality parameters tested (P > 0.05). Increased doses (≥ 345 J cm) resulted in a 4.3% increase in clot times with no statistically significant change in protein activity or levels. Overall, this study has demonstrated that the effective microbicidal 405 light dose shows little to no negative effect on plasma quality.
PubMed: 38842656
DOI: 10.1186/s13568-024-01725-0 -
Acta Anaesthesiologica Scandinavica Jun 2024Platelet transfusions are frequently used in the intensive care unit (ICU), but current practices including used product types, volumes, doses and effects are unknown.
BACKGROUND
Platelet transfusions are frequently used in the intensive care unit (ICU), but current practices including used product types, volumes, doses and effects are unknown.
STUDY DESIGN AND METHODS
Sub-study of the inception cohort study 'Thrombocytopenia and Platelet Transfusions in the ICU (PLOT-ICU)', including acutely admitted, adult ICU patients with thrombocytopenia (platelet count <150 × 10/L). The primary outcome was the number of patients receiving platelet transfusion in ICU by product type. Secondary outcomes included platelet transfusion details, platelet increments, bleeding, other transfusions and mortality.
RESULTS
Amongst 504 patients with thrombocytopenia from 43 hospitals in 10 countries in Europe and the United States, 20.8% received 565 platelet transfusions; 61.0% received pooled products, 21.9% received apheresis products and 17.1% received both with a median of 2 (interquartile range 1-4) days from admission to first transfusion. The median volume per transfusion was 253 mL (180-308 mL) and pooled products accounted for 59.1% of transfusions, however, this varied across countries. Most centres (73.8%) used fixed dosing (medians ranging from 2.0 to 3.5 × 10 platelets/transfusion) whilst some (mainly in France) used weight-based dosing (ranging from 0.5 to 0.7 × 10 platelets per 10 kg body weight). The median platelet count increment for a single prophylactic platelet transfusion was 2 (-1 to 8) × 10/L. Outcomes of patients with thrombocytopenia who did and did not receive platelet transfusions varied.
CONCLUSIONS
Among acutely admitted, adult ICU patients with thrombocytopenia, 20.8% received platelet transfusions in ICU of whom most received pooled products, but considerable variation was observed in product type, volumes and doses across countries. Prophylactic platelet transfusions were associated with limited increases in platelet counts.
PubMed: 38840310
DOI: 10.1111/aas.14467 -
The International Journal of Lower... Jun 2024The objective was to examine the efficacy of autologous platelet-rich gel (APG) in treating diabetic wound and investigate the association between APG and...
The objective was to examine the efficacy of autologous platelet-rich gel (APG) in treating diabetic wound and investigate the association between APG and ferritinophagy. A total of 32 patients with diabetic foot (DF) and Wagner grade 1 to 2 were included. Within the APG group, individuals with DF received weekly APG treatment. In the non-APG group, DF patients received daily dressing changes. Flow cytometry quantified the proportion of endothelial progenitor cells (EPCs) in peripheral blood on days 0 and 10. The diabetic rat model was induced using Streptozotocin. Two circular skin wounds were created on the backs of rats. The normal glucose group received daily dressing changes on the wound. In the diabetic group, the left wound underwent daily dressing changes, whereas the right wound was treated with APG once a week. CD34 levels were tested 7 days after the skin damage. The levels of glutathione peroxidase 4 (GPX4), Nuclear Receptor Coactivator 4 (NCOA4), Light chain 3 (LC3), and Masson staining were quantified on 14 days. The wound area and wound healing rate were separately measured at 0 and 14 days after the injury, regardless of DF patients or diabetic rats. The wound healing rate was higher in the APG group than in the non-APG group, regardless of DF patients or diabetic rats. The APG group had a greater ΔEPCs% in DF patients than the non-APG group. Regarding rat experiment, the APG group exhibited lower levels of NCOA4, and LC3 expressions and a shorter wound healing time. However, the APG group showed higher levels of CD34 expression, GPX4 protein, and collagen fibers than the non-APG group. Autologous platelet-rich gel accelerated the wound healing rate in diabetic populations and rats. Autologous platelet-rich gel promoted EPCs counts, collagen fiber volume, and vessel numbers. Autologous platelet-rich gel decreased LC3 and NCOA4 expression, but increased GPX4 protein expression. The possible mechanism was the inhibition of ferritinophagy.
PubMed: 38839257
DOI: 10.1177/15347346241258528 -
Blood Jun 2024Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening autoimmune disorder caused by ADAMTS13 deficiency. Caplacizumab, an anti-VWF nanobody, is...
Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening autoimmune disorder caused by ADAMTS13 deficiency. Caplacizumab, an anti-VWF nanobody, is approved for iTTP treatment, reducing the need for therapeutic plasma exchange (TPE) and improving platelet count recovery and survival. We conducted a retrospective study on 42 acute iTTP cases in Austria and Germany, treated with a modified regimen aimed at avoiding TPE if platelet count increased after the first caplacizumab dose. Baseline characteristics and patient outcomes were compared with a control group of 59 patients with iTTP, receiving frontline treatment with TPE, caplacizumab, and immunosuppression. The main outcome was the time to platelet count normalization. Secondary outcomes included clinical response, exacerbation, refractory iTTP, iTTP-related deaths, and the time to platelet count doubling. The median time to platelet count normalization was similar between the two cohorts (3 and 4 days; P = 0.31). There were no significant differences in clinical response, exacerbations, refractoriness, iTTP-related deaths, or time to platelet count doubling reflecting the short-term treatment response. Four patients did not respond to the first caplacizumab dose and TPE was subsequently initiated. Cytomegalovirus infection, HIV/hepatitis B co-infection, an ovarian teratoma with associated anti-platelet antibodies, and multiple platelet transfusion before the correct diagnosis may have impeded immediate treatment response in these patients. In conclusion, caplacizumab and immunosuppression alone, without TPE, rapidly controlled thrombotic microangiopathy and achieved a sustained clinical response in iTTP. Our study provides a basis for TPE-free iTTP management in experienced centers via shared decision-making between patients and treating physicians.
PubMed: 38838300
DOI: 10.1182/blood.2023023780 -
British Journal of Haematology Jun 2024The degree of anaemia in sickle cell disease (SCD) is a well-known contributor to morbidity and mortality. We aimed to explore the factors affecting haemoglobin (Hb)...
Determinants of the haemoglobin level in patients with sickle cell disease living in sub-Saharan Africa: Major impact of the country of residence and independent effects of leucocyte and platelet counts and haemolysis.
The degree of anaemia in sickle cell disease (SCD) is a well-known contributor to morbidity and mortality. We aimed to explore the factors affecting haemoglobin (Hb) level in African SCD patients, considering haemolysis biomarkers (LDH and bilirubin level, and reticulocyte count), leucocyte and platelet counts and socio-demographic characteristics (gender, age group, country of residence and BMI). The research was part of the CADRE multinational cohort and involved 3699 SCD patients living in Mali, Senegal, Ivory Coast, Democratic Republic of Congo, Gabon and Cameroon: 2936 SS/Sβ0, 587 SC and 176 Sβ + patients with median Hb level of 8, 11.3 and 11.2 g/dL respectively (p < 0.001). In multivariate analysis conducted in 1394 SS/Sβ0 patients, living in Cameroon, female gender, lower BMI, higher haemolysis markers (especially LDH) and higher leucocyte and platelet counts were independently associated with lower Hb level (all p < 0.05). In 497 SC and 156 Sβ + patients, female gender (p < 0.001), lower BMI (p < 0.05) and higher platelet counts (p < 0.001) were independently associated with lower Hb level. Anaemia in African SCD patients is not only associated with haemolysis but also with the country of residence, lower BMI and leucocyte or platelet counts which might reflect inflammation related to infectious burden in the region.
PubMed: 38831605
DOI: 10.1111/bjh.19576 -
Archives of Razi Institute Dec 2023Snake venoms are rich in valuable substances that have medical potential in the diagnosis and treatment of hemostatic diseases. The present paper was aimed at the...
Snake venoms are rich in valuable substances that have medical potential in the diagnosis and treatment of hemostatic diseases. The present paper was aimed at the purification and functional characterization basis of a thrombin-like enzyme and its role in the functioning of the coagulation cascade and platelet aggregation pathway. A thrombin-like serine protease was purified from the Iranian venom (TLIECV), employing a one-step chromatographic procedure. This peptide was collected in high yield and purity by a single chromatographic step using RP-HPLC equipped with a C column. This peptide showed a 3000 Da molecular weight in gel-electrophoresis. Evidence in the SDS-PAGE gel has confirmed high recovery of fraction in optimal terms. Subsequently, this peptide was identified via its intact molecular mass and peptide mass fingerprint (PMF) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF/MS). Multiple sequence alignments were performed by ClustalW, the Bioedit software. Molegro Data Modeller (MDM) 3.0 software was used to predict the putative tertiary structure of the peptide. The enzyme possessed fibrinogenolytic, procoagulant, and aggregation inducer properties. Moreover, the SDS-PAGE (12%) was applied to examine fibrinogenolytic function. The purified enzyme degraded the Aα chain of fibrinogen while the Bβ and γ chains were not digested. According to that, the deficient human plasma in factor X and normal human plasma were also coagulated by TLIECV, it takes part in the common and intrinsic routes of the coagulation cascade. These findings proved that TLIECV is a serine protease identical to procoagulant thrombin-like snake venom proteases; however, it specifically releases the Aα chain of bovine fibrinogen. Because of its function to make up for the deficiency of factor X and its platelet aggregation inducer property, TLIECV could be considered a molecular impact to reveal the hemostasis mechanisms.
Topics: Viperidae; Animals; Viper Venoms; Iran; Thrombin; Platelet Aggregation; Humans; Electrophoresis, Polyacrylamide Gel; Amino Acid Sequence; Echis; Venomous Snakes
PubMed: 38828174
DOI: 10.32592/ARI.2023.78.6.1822 -
Pediatric Research May 2024Severe aplastic anemia (SAA) is caused by immune-mediated destruction. Standard immunosuppressive therapy (IST) is effective but needs to be improved.
BACKGROUND
Severe aplastic anemia (SAA) is caused by immune-mediated destruction. Standard immunosuppressive therapy (IST) is effective but needs to be improved.
METHODS
The data of patients with SAA and received IST were analyzed retrospectively to conducted this historical control study.
RESULTS
A total of 115 SAA patients (60 males; median age of 5.77 years and median follow-up time of 45 months) were enrolled in this study. The complete response rates (CRR) of the eltrombopag group at 3 and 6 months were higher than the control group (30.3% vs.8.2% at 3 months; 50.0% vs. 10.2% at 6 months). The overall response rates (ORR) showed no differences. There were significant differences in the times from G-CSF, Red blood cell transfusion, and Platelet transfusion between the two groups. No difference in overall survival (OS), event-free survival (EFS), and relapse rate between two groups. There is no variable were associated with prognosis in both groups.
CONCLUSION
Addition of eltrombopag to IST confers faster hematological response and higher early hematological response in pediatric SAA patients.
IMPACT
Addition of eltrombopag to standard immunosuppressive therapy confers faster hematological response and higher early hematological response in pediatric severe aplastic anemia patients. Eltrombopag showed reliable safety but had no impact on long-term response and prognosis. This article is a historical controlled study consisting of 115 pediatric severe aplastic anemia patients and makes up for the lack of clinical data deficient on pediatric severe aplastic anemia with TPO-RA combined with IST.
PubMed: 38822136
DOI: 10.1038/s41390-024-03253-w -
Cytotherapy Apr 2024Mesenchymal stromal cells (MSCs) exert immunomodulatory effects, primarily through released extracellular vesicles (EVs). For the clinical-grade manufacturing of MSC-EV...
Calcium chloride declotted human platelet lysate promotes the expansion of mesenchymal stromal cells and allows manufacturing of immunomodulatory active extracellular vesicle products.
BACKGROUND
Mesenchymal stromal cells (MSCs) exert immunomodulatory effects, primarily through released extracellular vesicles (EVs). For the clinical-grade manufacturing of MSC-EV products culture conditions need to support MSC expansion and allow the manufacturing of potent MSC-EV products. Traditionally, MSCs are expanded in fetal bovine serum-supplemented media. However, according to good manufacturing practice (GMP) guidelines the use of animal sera should be avoided. To this end, human platelet lysate (hPL) has been qualified as an animal serum replacement. Although hPL outcompetes animal sera in promoting MSC expansion, hPL typically contains components of the coagulation system that need to be inhibited or removed to avoid coagulation reactions in the cell culture. Commonly, heparin is utilized as an anticoagulant; however, higher concentrations of heparin can negatively impact MSC viability, and conventional concentrations alone do not sufficiently prevent clot formation in prepared media.
METHODS
To circumvent unwanted coagulation processes, this study compared various clotting prevention strategies, including different anticoagulants and calcium chloride (CaCl)-mediated declotting methods, which in combination with heparin addition was found effective. We evaluated the influence of the differently treated hPLs on the proliferation and phenotype of primary bone marrow-derived MSCs and identified the CaCl-mediated declotting method as the most effective option. To determine whether CaCl declotted hPL allows the manufacturing of immunomodulatory MSC-EV products, EVs were prepared from conditioned media of MSCs expanded with either conventional or CaCl declotted hPL. In addition to metric analyses, the immunomodulatory potential of resulting MSC-EV products was assessed in a recently established multi-donor mixed lymphocyte reaction assay.
RESULTS AND CONCLUSIONS
Our findings conclusively show that CaCl-declotted hPLs support the production of immunomodulatory-active MSC-EV products.
PubMed: 38819364
DOI: 10.1016/j.jcyt.2024.04.069