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Background: Common variable immunodeficiency is the most prevalent symptomatic primary immunodeficiency in adults. Affected patients fail to mount an appropriate humoral response against community acquired infectious diseases and recent reports have provided data supporting the increased susceptibility of these patients to severe SARS-CoV-2 infections. In this context, the infusion of COVID-19 convalescent plasma could represent an effective therapeutic strategy. Case presentation: 25-year old woman diagnosed with common variable immunodeficiency in 2013, developed severe COVID-19 that rapidly progressed to pneumonia presenting with multiple bilateral lung opacities that were both central and peripheral and presented as ground-glass and consolidation types involving all lobes, bilaterally. As blood oxygen saturation decayed and lung abnormalities were not responsive to large spectrum antibiotics and corticosteroids, patient was placed on mechanical ventilation and compassionate-use of approved COVID-19 convalescent donor plasma was introduced. The patient presented a rapid response to the approach and mechanical ventilation could be interrupted 24 h after first dose of COVID-19 convalescent donor plasma. As a whole, the patient received four doses of 200 mL convalescent plasma during a period of 6 days. There was rapid improvement of clinical status, with interruption of supplemental oxygen therapy after 6 days and reduction of lung abnormalities as evidence by sequential computed tomography scans. Conclusions: This is a single patient report that adds to other few reports on common variable immunodeficiency and agammaglobulinemia, suggesting that COVID-19 convalescent donor plasma could be a valuable therapeutic approach to treat patients affected by dysgammaglobulinemias and presenting severe COVID-19. [ABSTRACT FROM AUTHOR]

Abstract Exosomes may represent an interesting antigenic pulse for new forms of anti-tumor immunotherapy. We evaluated exosomes from serum of patients with acute myeloid leukemia (AML) as an antigenic source for dendritic cells (DC) and the effects upon antitumor cytotoxicity, assessed by the percentage of specific lysis of K562 leukemic cells in co-cultures. Surprisingly, incubation of exosomes with DCs decreased lysis of K562, which may correspond to a mechanism of tumor evasion in vivo. However, when immature DCs were pulsed with exosomes purified from K562 culture supernatants, the lysis of target cells was notably enhanced, associated with a substantial increase in the expression of the maturation marker CD83. Thus, the development of vaccines using patients' exosomes would probably add no benefits to the treatment of AML; alternately, exosomes from cultured cells may represent an effective way for maturing DCs into a cytotoxic phenotype, without the immunosuppression observed with patients' exosomes. [ABSTRACT FROM AUTHOR]

Key Clinical Message This manuscript describes the case of a patient with sickle cell anemia who died of fulminant hepatitis after therapy with the iron chelator Deferasirox. The patient was homozygous for the −1774delG polymorphism in the Abcc2 gene, which raises the concern about the use of hepatotoxic drugs in this specific context. [ABSTRACT FROM AUTHOR]

Objectives: In sickle cell/β-thalassemia, mutations in the corresponding β-globin genes are responsible for complex pathological events resulting in diverse clinical complications. The objective of this study was to provide an overview of the clinical and laboratory characteristics of patients with the syndrome, and of the degree of severity of clinical manifestations resulting from the β-thalassemia mutation. Methods: A retrospective chart review was performed on 46 patients with sickle cell/β-thalassemia (31 Sβo and 15 Sβ+), evaluating hematological parameters and end organ damage. Statistical analyzes were carried out in order to highlight differences between the two groups according to the nature of the thalassemia mutation. Results: As expected, patients with the Sβo phenotype had a higher degree of hematological involvement in comparison to Sβ+ patients; with lower hemoglobin levels, and signs of more intense chronic hemolysis. However, Sβ+ patients were more prone to the occurrence of acute chest syndrome. The impact of the thalassemia mutation upon total body and bone composition was also evident, as Sβo patients presented lower body mass index (BMI) and bone mineral density. The degree of bone damage correlated to lower BMI and hemoglobin levels, as well as plaquetosis, monocytosis and elevated lactate dehydrogenase, possibly reflecting the effects of hemolysis and inflammation upon bone metabolism and body constitution. Conclusions: This study identified significant differences among sickle cell/β-thalassemia patients according to the beta mutation involvement, pointing to an important predictor of disease severity. [ABSTRACT FROM AUTHOR]

Even after two years of the pandemic, a completely effective treatment against SARS-CoV-2 has not yet been established. Considering this fact and the emergence of successive new viral variants, the development of therapies based on natural polyclonal antibodies recovered from convalescent plasma remains relevant. This study presents a comparison between different methods of screening antibodies in samples of 41 individuals previously diagnosed with COVID-19. We found a significant correlation between Abbot Architect anti-SARS-CoV-2 IgG and Abbott Allinity SARS-CoV-2 IgG II Quantitative assay intensity of reactivity and neutralizing antibody (nAb) titers. Thus, we propose an initial antibody screening with IgG anti-N Abbott Architect test, with an index of, for example, > 3.25 or SARS-CoV-2 IgG II Quantitative Abbott Allinity assay > 137.65 AU/mL as good predictors of Nab ≥ 1:80. For the quantitative method, this threshold demonstrated a 100 % sensitivity and 80 % specificity, with 97.3 % accuracy. An interesting observation was the increase in the neutralizing activity of the anti-SARS-CoV-2 antibodies with the longest interval between the end of the symptoms and the collection, demonstrating that the delay in plasma collection does not affect the achievement of adequate nAbs levels. These results demonstrate the possibility of using faster and more widely available commercial serological tests with a good correlation with viral neutralization tests in culture, allowing for optimized large-scale donor selection, which will be of utmost importance for the development of therapies such as hyperimmune immunoglobulin. • Commercial serological tests for anti-SARS-CoV-2 antibodies show good correlation with neutralizing antibodies in culture. • This study demonstrates accurate cut-off points in serological tests for the selection of donors with nAbs > 1:80. • We propose a strategy for the selection of donors that can be useful for the production of therapeutics on a large scale. [ABSTRACT FROM AUTHOR]

Background: Pregnancy represents a challenge for women with sickle cell disease (SCD), with higher rates of both maternal and fetal complications. The aim of this study was to evaluate the impact of prophylactic transfusion support administered specifically to pregnant women with sickle hemoglobin C disease.Materials and Methods: Patients were divided into two groups according to the type of transfusion support received: 10 women received prophylactic erythrocytapheresis or manual exchange transfusion at 28 weeks of gestation, and 14 received transfusions only on demand, due to acute complications, or received no transfusions at all.Results: Our results indicated higher frequencies of SCD-related complications in the group that did not receive prophylactic transfusion support (35.7% vs. only 10% in the erythrocytapheresis group). Furthermore, these complications were more severe in this group and included all cases of acute chest syndrome. A significant difference was observed concerning gestational age at birth (38.7 weeks in the transfusion group vs. 34.4 weeks, p = 0.037), with a higher frequency of preterm births in the nontransfused group (69.23% vs. 30% in the transfusion group).Conclusion: We demonstrated a clear reduction of unfavorable outcomes in patients receiving prophylactic transfusions, probably reflecting better maternal and fetal conditions, which corroborated to the more satisfactory indices of vitality, observed in newborns. Considering that erythrocytapheresis or manual exchange transfusions both represent feasible and safe procedures, they could represent important tools for the optimal management of these patients. [ABSTRACT FROM AUTHOR]

Bone marrow is organized in specialized microenvironments known as 'marrow niches'. These are important for the maintenance of stem cells and their hematopoietic progenitors whose homeostasis also depends on other cell types present in the tissue. Extrinsic factors, such as infection and inflammatory states, may affect this system by causing cytokine dysregulation (imbalance in cytokine production) and changes in cell proliferation and self-renewal rates, and may also induce changes in the metabolism and cell cycle. Known to relate to chronic inflammation, obesity is responsible for systemic changes that are best studied in the cardiovascular system. Little is known regarding the changes in the hematopoietic system induced by the inflammatory state carried by obesity or the cell and molecular mechanisms involved. The understanding of the biological behavior of hematopoietic stem cells under obesity-induced chronic inflammation could help elucidate the pathophysiological mechanisms involved in other inflammatory processes, such as neoplastic diseases and bone marrow failure syndromes. [ABSTRACT FROM AUTHOR]

Objectives: APAF-1 is a central component of the intrinsic pathway of apoptosis, where APAF-1 dysregulation results in the development of diverse human neoplasms. The aim of this study was to characterize the mRNA expression levels of APAF-1 transcripts in low-risk and high-risk MDS and to elucidate whether the expression levels of APAF-1 transcripts are modulated with increased apoptosis in CD34+ MDS cells undergoing erythroid differentiation. Methods: APAF-1 ( ) expression was verified, by quantitative RT-PCR, in bone marrow aspirates from 33 patients with myelodysplastic syndromes (MDS), at the time of diagnosis, and in erythroid differentiation cultures from CD34+ from normal donors and patients with MDS. Results: APAF-1 expression was significantly higher in low-risk, compared to high-risk MDS, according to IPSS ( P < 0.0001), FAB ( P = 0.0265), and cytogenetic risk ( P = 0.0134). Low-risk MDS-derived differentiated erythroid cells demonstrated an increased expression of APAF-1, compared with normal cells, accompanied by an augmented rate of apoptosis. Conclusions: Increased expression of APAF-1 in low-risk disease and its positive correlation with the apoptotic rate observed during the erythroblast differentiation of low-risk MDS cells may indicate that the modulation of APAF-1, at the transcriptional level, participates in the pathophysiology of MDS. [ABSTRACT FROM AUTHOR]

Dendritic cells play a fundamental role in the antitumor immunity cycle, and the loss of their antigen-presenting function is a recognized mechanism of tumor evasion. We have recently demonstrated the effect of exosomes extracted from serum of patients with acute myeloid leukemia as important inducers of dendritic cell immunotolerance, and several other works have recently demonstrated the effects of these nanoparticles on immunity to other tumor types as well. The aim of this review was to highlight the recent findings on the effects of tumor exosomes on dendritic cell functions, the mechanisms by which they can lead to tumor evasion, and their manipulation as a possible strategy in cancer treatment. [ABSTRACT FROM AUTHOR]

Sickle cell disease is a chronic inflammatory condition characterized by elevated levels of inflammatory cytokines, which may be regulated by genetic polymorphisms and could be associated with diverse disease presentations and alloimmunization. The aim of this study was to evaluate Treg and Th17 cell frequencies, cytokine gene polymorphisms, and their association with cytokine expression profile in patients with sickle cell disease. For that purpose, we evaluated the IL intron 3 variable number tandem repeat (VNTR, genotypes 1.1, 1.2, 2.2, and 2.3), IL4-T590C>T, IL6-174G>C, TNFα-308G>A, IL10-819T>C, IL10-592A>C, and IL10-1082A>G polymorphisms and their correlation with TGFβ, IL4, IL6, and IL10 gene expression in sickle cell patients. We observed a significant decrease in Treg frequency together with a substantial increase in Th17 response in patients with sickle cell disease compared with healthy controls ( p < 0.001 and p = 0.014, respectively). There was also a higher prevalence of the IL4-590T/T genotype in patients with sickle cell disease than in Afro-Brazilian descendent controls ( p < 0.001) and higher expression of IL4 in patients with the 1.1 genotype of IL4 intron 3 VNTR ( p = 0.06). Significantly greater gene expression of TGFβ, IL6, and IL10 was observed in sickle cell patients when compared with controls ( p = 0.01, 0.03, and <0.001, respectively). Moreover, higher levels of interleukin-6 and -10 were observed in the group of alloimmunized patients. These new data bring insights into the deregulation in the immune system affecting sickle cell patients and must be further investigated in larger cohorts to better characterize individual variations in immune responses and new markers for disease morbidity. [ABSTRACT FROM AUTHOR]

Purpose Despite not yet explored, the serum lactate dehydrogenase (LDH) level in hemoglobinopathy SC (HbSC) patients could be a marker of disease severity as this association is strong in sickle cell patients. We hypothesized that the degree of hemolysis in HbSC patients is a key determinant influencing a spectrum of complications that reflect the severity of HbSC vasculopathy. The aim of this study was to analyze the associations between hemolytic parameters and chronic complications in adult SC patients. Findings We demonstrated that LDH reflects the overall rate of hemolysis and presents a correlation with the complications related to the hemolytic subphenotype: retinopathy, venous thromboembolism and leg ulcers in HbSC patients. Remarkably, this simple biomarker was associated with a clinical subphenotype of complications in patients with HbSC disease. Conclusions We propose that LDH elevation identifies HbSC patients with hemolysis, which could be a marker of endothelial dysfunction and end-organ vasculopathy. The use of this test as a marker of disease severity could complement the decisions taken during HbSC patient management. [ABSTRACT FROM AUTHOR]

There is no consensus on the risk-benefit status of preoperative autologous blood donation (PAD) for healthy bone marrow donors and there is concern regarding its impact on the development of pre-surgical anemia. We evaluated the changes in hemoglobin levels related to PAD in 80 bone marrow donors of our institution between 2002 and 2016. Mean Hgb values were compared separately for donors who donated 1 or 2 units, at 3 time-points: before PAD collection, the morning before marrow harvest and soon after harvest. Mean baseline Hgb values did not differ significantly between the 2 groups. After PAD collection, there was a significant drop in Hgb levels for the whole cohort of donors but more pronounced for the group that donated 2 units [1 unit: 12.8(8.9–17.4) × 2 units: 11.55(11.2–12.1), p = 0.045]. However, after marrow harvest, Hgb levels were similar for the 2 groups; 61.2% of all donors required autologous transfusion and none required allogeneic transfusion. Furthermore, baseline Hgb <14.35 g/dL was identified as the sensitive cutoff to predict the need for transfusion after marrow harvest (sensitivity of 52% and specificity of 80.4%, p = 0.001). Thus, our analysis demonstrates the possibility of using hemoglobin thresholds as cutoff points for indication of PAD, tending to a more cost-effective approach. Despite significant declines in Hgb levels after PAD, none of the donors in our cohort required allogeneic transfusion, demonstrating the safety of this procedure. Thus, the indication of PAD remains an option for those who feel insecure despite higher baseline Hgb levels. [ABSTRACT FROM AUTHOR]

Abstract: Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal stem cell disorders characterized by abnormal hematopoietic differentiation and maturation, which progress toward acute leukemia in approximately 30% of the cases. Drug metabolism polymorphisms in Cytochrome P450 2B6 (CYP2B6), Glutathione S-transferase (GST) and Dehydrogenase Quinone 1 (NQO1) enzymes and P-glycoprotein (MDR-1) could modify enzyme activity. Thus, the aim of this study was to identify the influence of CYP2B6 G15631T, GSTT1, GSTM1, NQO1 C609T and MDR-1 C3435T polymorphisms on MDS progression. We analyzed 78 MDS patients using the PCR-RFLP and multiplex method. The frequency of GST deletions and MDR-1 CC genotype was lower in progression-free patients compared to patients with progression; GST: 17% vs. 35% (P =0.018); MDR-1 gene: 19% vs. 48% (P =0.012). We also verified the influence of GST deletions and MDR-1 C3435T on patient overall survival and found no significant difference (RR =0.75; P =0.599 and RR =0.79; P =0.594 respectively). We concluded that GSTM1 deletion may contribute toward MDS progression probably due to toxic metabolite accumulation which generates cell toxicity and DNA damage. Moreover, MDR-1 C3435T may have a protective effect against MDS progression because the expected lower expression of P-glycoprotein would lead to a higher degree of cell death. To the best of our knowledge, this is the first study showing the relationship of these polymorphisms with MDS progression. [Copyright &y& Elsevier]

Background and Objectives: This report describes the implementation of the first pre‐hospital transfusion service in Latin America, with red blood cell concentrates available for immediate use in mobile land units. Materials and Methods: A partnership was established between the Regional Mobile Emergency Service and the Regional Blood Bank, with further development of protocols for the storage, transportation and transfusion of red blood cell concentrates in an ambulance, with the acquisition of special thermal boxes, a heater for blood components and digital thermometers. Results: The Service was developed from May 2019 and implemented in September 2020, in a mobile intensive care unit serving 11 cities, reaching a population of approximately 480 000 inhabitants. Two red blood cell concentrates, type 'O' RhD negative, are available, stored in a special sealed thermal box and with continuous temperature monitoring. A specific transfusion protocol was developed, in accordance with the institutional protocols of the Hospital and its Blood Bank. Conclusion: This is the first description of a pre‐hospital transfusion service implemented in Latin America, with the potential to reduce the number of deaths from civil trauma and which can be extrapolated to other institutions or countries in similar conditions. [ABSTRACT FROM AUTHOR]

Objectives: Deferasirox is an oral iron chelator with established dose-dependent efficacy for the treatment of iron overload secondary to transfusion. However, there is few data reporting the use of Desferasirox in adult patients with sickle cell disease (SCD) and transfusional iron overload. Methods: We conducted a prospective, single center, nonrandomized study from January 2014 to March 2015 in Campinas, Brazil. Seven patients (five women, median age 50 y.o.) who were followed up on regular transfusion program were treated with a single daily dose of deferasirox (median dose 20 mg/kg). They were monitored for clinical symptoms, renal function and hepatotoxicity. Results: One patient discontinued the study due to lack of compliance. Two patients reported mild to moderate adverse events (gastrointestinal disturbances). Five patients had the drug discontinued due to worsening of renal function. One patient had the drug discontinued due to severe hepatotoxicity that evolved to death; no patient finished the study. Discussion and conclusions: Deferasirox does not appear to be well tolerated in SCD patients older than 40 years, in which complications of the underlying disease are already fully installed. The choice of the ideal iron chelator for this population should include an evaluation of comorbidities and organic dysfunctions, as well as the need to find pharmacogenetic safety markers in this group of patients. [ABSTRACT FROM AUTHOR]

Objectives: Deferasirox is an oral iron chelator with established dose-dependent efficacy for the treatment of iron overload secondary to transfusion. However, there is few data reporting the use of Desferasirox in adult patients with sickle cell disease (SCD) and transfusional iron overload. Methods: We conducted a prospective, single center, nonrandomized study from January 2014 to March 2015 in Campinas, Brazil. Seven patients (five women, median age 50 y.o.) who were followed up on regular transfusion program were treated with a single daily dose of deferasirox (median dose 20 mg/kg). They were monitored for clinical symptoms, renal function and hepatotoxicity. Results: One patient discontinued the study due to lack of compliance. Two patients reported mild to moderate adverse events (gastrointestinal disturbances). Five patients had the drug discontinued due to worsening of renal function. One patient had the drug discontinued due to severe hepatotoxicity that evolved to death; no patient finished the study. Discussion and conclusions: Deferasirox does not appear to be well tolerated in SCD patients older than 40 years, in which complications of the underlying disease are already fully installed. The choice of the ideal iron chelator for this population should include an evaluation of comorbidities and organic dysfunctions, as well as the need to find pharmacogenetic safety markers in this group of patients. [ABSTRACT FROM AUTHOR]