Phenotypes of STAT3 gain-of-function variant related to disruptive regulation of CXCL8/STAT3, KIT/STAT3, and IL-2/CD25/Treg axes.

STAT3 is a cytokine-signaling transcription factor critical for gene regulation. Gain-of-function (GOF) mutations in STAT3 are associated with lymphoproliferation, autoimmune cytopenias, increased susceptibility to infection, early-onset solid-organ autoimmunity, short stature, and eczema. We studied the JAK/STAT signaling pathway gene expression and the cytokine profile in two families carrying STAT3-GOF variants to shed light on the STAT3-GOF-associated variable expressivity, including the identification of disease markers.

Inflammatory Dendritic Cells Contribute to Regulate the Immune Response in Sickle Cell Disease.

Sickle cell disease (SCD), one of the most common hemoglobinopathies worldwide, is characterized by a chronic inflammatory component, with systemic release of inflammatory cytokines, due to hemolysis and vaso-occlusive processes. Patients with SCD demonstrate dysfunctional T and B lymphocyte responses, and they are more susceptible to infection. Although dendritic cells (DCs) are the main component responsible for activating and polarizing lymphocytic function, and are able to produce pro-inflammatory cytokines found in the serum of patients with SCD, minimal studies have thus far been devoted to these cells.

Clinical relevance of heterozygosis for aceruloplasminemia.

Aceruloplasminemia is a rare form of brain iron overload of autosomal recessive inheritance that results from mutations in the CP gene, encoding the iron oxidase ceruloplasmin. Homozygous aceruloplasminemia causes progressive neurodegenerative disease, anemia, and diabetes, and is usually diagnosed late in life upon investigation of anemia, high ferritin, or movement disorders, but its heterozygous state is less characterized and believed to be silent. Here we report two heterozygotes for new mutations causing aceruloplasminemia from whom peripheral blood samples were collected for complete blood counts, iron studies, and genotyping by automated sequencing.

Deferasirox associated with liver failure and death in a sickle cell anemia patient homozygous for the -1774delG polymorphism in the gene.

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 gene, which raises the concern about the use of hepatotoxic drugs in this specific context.

Reduced rate of sickle-related complications in Brazilian patients carrying HbF-promoting alleles at the BCL11A and HMIP-2 loci.

The presence of high levels of fetal haemoglobin (HbF) provides well-validated clinical benefits to patients with sickle cell anaemia (SCA). Nevertheless it has been difficult to show clear direct effects of the known genetic HbF modifiers, such as the enhancer polymorphisms for haematopoietic transcription factors BCL11A and MYB, on SCA severity. Investigating SCA patients from Brazil, with a high degree of European genetic admixture, we have detected strong effects of these variants on HbF levels.

NAT2, XRCC1 and hOGG1 polymorphisms, cigarette smoking, alcohol consumption and risk of upper aerodigestive tract cancer.

Aim: To evaluate associations between polymorphisms of the N-acetyltransferase 2 (NAT2), human 8-oxoguanine glycosylase 1 (hOGG1) and X-ray repair cross-complementing protein 1 (XRCC1) genes and risk of upper aerodigestive tract (UADT) cancer.

Patients And Methods: A case-control study involving 117 cases and 224 controls was undertaken. The NAT2 gene polymorphisms were genotyped by automated sequencing and XRCC1 Arg399Gln and hOGG1 Ser326Cys polymorphisms were determined by Polymerase Chain Reaction followed by Restriction Fragment Length Polymorphism (PCR-RFLP) methods.

Erythropoiesis-driven regulation of hepcidin in human red cell disorders is better reflected through concentrations of soluble transferrin receptor rather than growth differentiation factor 15.

Growth differentiation factor 15 (GDF-15) is a bone marrow-derived cytokine whose ability to suppress iron regulator hepcidin in vitro and increased concentrations found in patients with ineffective erythropoiesis (IE)suggest that hepcidin deficiency mediated by GDF-15 may be the pathophysiological explanation for nontransfusional iron overload. We aimed to compare GDF-15 production in anemic states with different types of erythropoietic dysfunction. Complete blood counts, biochemical markers of iron status, plasma hepcidin, GDF-15, and known hepcidin regulators [interleukin-6 and erythropoietin (EPO)] were measured in 87 patients with red cell disorders comprising IE and hemolytic states: thalassemia, sickle cell anemia, and cobalamin deficiency.

Gene expression analysis of the Brazilian type of hereditary persistence of fetal hemoglobin: identification of genes that could be related to γ-globin activation.

Increased γ-globin production and consequent fetal hemoglobin (Hb F, α2γ2) formation is an important modulator of the clinical and hematological features of hemolytic anemias, such as sickle cell disease and β-thalassemia (β-thal). Hb F genes are genetically regulated, but despite numerous studies, the molecular basis of hemoglobin (Hb) switching is not completely understood. Hereditary persistence of fetal Hb (HPFH) is a consequence of impaired switching in adult life, which results in the continued expression of the γ-globin gene.

JAK2 V617F mutation prevalence in myeloproliferative neoplasms in Pernambuco, Brazil.

Background: The JAK2 V617F mutation is associated with three myeloproliferative neoplasms (MPNs): polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). It generates an unregulated clonal hematopoietic progenitor and leads to abnormal increased proliferation of one or more myeloid lineages. Subjects bearing this mutation may present more frequently with complications such as thrombosis and bleeding, and no specific treatment has yet been developed for BCR-ABL-negative JAK2 V617F-negative MPNs.

Trypanosoma cruzi: parasite persistence in tissues in chronic chagasic Brazilian patients.

Chagas disease in the chronic phase may develop into cardiac and/or digestive forms. The pathogenesis of the disease is not yet clear and studies have been carried out to elucidate the role of parasite persistence in affected organs. The aim of this study was to detect and quantify Trypanosoma cruzi in paraffin-embedded tissue samples from chronic patients using NPCR (nested polymerase chain reaction) and QPCR (quantitative polymerase chain reaction) methods.

Reduction of AHSP synthesis in hemin-induced K562 cells and EPO-induced CD34(+) cells leads to alpha-globin precipitation, impairment of normal hemoglobin production, and increased cell death.

Objective: alpha-Hemoglobin stabilizing protein (AHSP) binds alpha-hemoglobin (Hb), avoiding its precipitation and its pro-oxidant activity. In the presence of betaHb, the alphaHb-AHSP complex is dismembered and betaHb displaces AHSP to generate the quaternary structure of Hb. The relationship between Hb formation and alterations in AHSP expression, which may affect human erythropoiesis, has not yet been described in human cells.

Identification of beta thalassemia mutations in South Brazilians.

We have evaluated the mutation profile in a sample of 127 unrelated beta-thalassemia (beta thal) individuals, diagnosed through A2 and fetal hemoglobin quantification by high-performance liquid chromatography (HPLC) from the Brazilian southernmost state, where a flow of Italian immigrants had occurred in the late 19th century, mainly from Northern Italy. The molecular analysis was performed by DNA sequencing of the most common mutations found in the Mediterranean region. The beta 0 codon 39 nonsense mutation was the most frequent alteration (50.

DNAase I hypersensitive site 3' to the beta-globin gene cluster containing two TAA insertions and a G-->A polymorphism is predominantly associated with the beta+-thalassemia IVS-I-6 (T-->C) mutation.

Analysis of DNA polymorphic sites is an important tool for the detection of gene flow in human evolutionary studies and to study the genetic background for gene mutations. The beta-globin locus contains several single-base restriction fragment length polymorphism (RFLP) sites throughout chromosome 11. In addition to these polymorphic sequence repeats, others are being studied in order to expand our knowledge concerning the role between haplotype-genotype and phenotype associations.

Genotyping of human cytomegalovirus using non-radioactive single-strand conformation polymorphism (SSCP) analysis.

Genetic variation in the glycoprotein B (gB) gene may play a role in human cytomegaloviruses (HCMVs) pathogenesis. Using restriction analysis of the gB gene product (PCR-RFLP), amplified by the nested polymerase chain reaction, the HCMV strains can be compared and classified into at least four HCMV groups. PCR single-strand conformation polymorphism (PCR-SSCP) is one of the techniques used to identify a mutant sequence or a polymorphism in a known gene.

Use of a nested polymerase chain reaction (N-PCR) to detect Trypanosoma cruzi in blood samples from chronic chagasic patients and patients with doubtful serologies.

Chagas disease, caused by Trypanosoma cruzi, is an important endemic illness in Latin America. Serologic tests for T. cruzi detection in blood are sensitive, but their specificity is unsatisfactory.