RESUMEN
Hemoglobinopathies constitute the most frequent monogenic disorders worldwide and thalassemias are the most frequent genetic disorders in Greece. Over a 5-year period (2002-2006), 1,375 couples were screened for hemoglobinopathies and counseled at our Thalassaemia Prevention Unit, Hippokration Hospital, Thessaloniki, Greece. In 148 cases (10.7%), both partners carried an abnormal hemoglobin (Hb) gene and genetic counseling was offered. One hundred out of 116 pregnancies were at-risk of giving birth to an offspring carrying either the homozygous or double heterozygous forms of the mutations under discussion. The remaining 16 pregnancies involved couples who were heterozygous for mutations that did not cause severe clinical disease, and were exempted from prenatal diagnosis. Twenty-six fetuses were found to be homozygotes or double heterozygotes for clinically significant mutations. These couples were informed of the danger of having an affected child but the termination or continuation of the pregnancy was left to the couples to decide. Nevertheless, all the couples preferred to terminate the pregnancies. The National Thalassaemia Prevention Programme has effectively decreased the incidence of thalassemia major and sickle cell syndromes in Greece.
Asunto(s)
Hemoglobinopatías/diagnóstico , Hemoglobinopatías/epidemiología , Heterocigoto , Diagnóstico Prenatal , Anemia de Células Falciformes/diagnóstico , Anemia de Células Falciformes/epidemiología , Anemia de Células Falciformes/genética , Composición Familiar , Femenino , Asesoramiento Genético , Pruebas Genéticas , Grecia/epidemiología , Hemoglobinopatías/genética , Humanos , Masculino , Embarazo , Talasemia/diagnóstico , Talasemia/epidemiología , Talasemia/genéticaRESUMEN
Hereditary spherocytosis (HS) is a heterogeneous group of disorders. The abnormal red cell morphology (resulting in shortened cell survival) is due to a primary deficiency in spectrin, ankyrin-1, band 3 or protein 4.2. Secondary protein deficiencies are often observed and may be involved in the outcome of the disease. In the present study, we searched for secondary erythrocyte membrane protein alterations in HS, including the lipid raft associated proteins and the oxidative index. For this purpose, 12 patients with clinical and laboratory diagnosis of mild to typical HS were examined. Erythrocyte membrane ghosts and skeletons were subjected to SDS-PAGE and immunoblotting analysis using antibodies against red cell membrane proteins and DNP moiety, after 2,4-dinitrophenylhydrazine derivatization. Protein deficiencies, degradation, aggregation and enhanced binding of cytoplasmic components, band 8, hemoglobin and immunoglobulins G to the membrane as well as increased oxidative index, were found in the majority of the HS patients. Proportion of the membrane- and skeleton-bound globin was oxidized/denatured Hb or hemichromes and crosslinkings. Some HS membranes are deficient in lipid rafts proteins and contain sorcin. A context of these distortions is more pronounced in typical HS cases compared to the mild ones. Similar defects in thalassemia and senescent RBCs are dictated by increased oxidative stress and are positively correlated with perturbations in membrane properties. These data add some new insight in the field of HS pathophysiology and clinical variability.
Asunto(s)
Membrana Eritrocítica , Eritrocitos/metabolismo , Hemoglobinas/metabolismo , Esferocitosis Hereditaria/sangre , Adolescente , Adulto , Niño , Preescolar , Citoesqueleto/metabolismo , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/patología , Eritrocitos/patología , Femenino , Humanos , Masculino , Lípidos de la Membrana/metabolismo , Microdominios de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Oxidación-Reducción , Esferocitosis Hereditaria/patologíaRESUMEN
Hemoglobin E-Saskatoon (beta22-Glu-Lys) is found worldwide but is extremely rarely. Two cases of pregnant women who carried the abnormal hemoglobin and the various problems that arise from it are reported. A discussion of the combinations with other abnormal hemoglobin is also presented.
Asunto(s)
Hemoglobina E/aislamiento & purificación , Complicaciones Hematológicas del Embarazo/sangre , Talasemia beta/sangre , Adulto , ADN/química , ADN/genética , Electroforesis , Femenino , Hemoglobina E/genética , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/aislamiento & purificación , Humanos , Recién Nacido , Masculino , Reacción en Cadena de la Polimerasa , Embarazo , Complicaciones Hematológicas del Embarazo/genética , Análisis de Secuencia de ADN , Talasemia beta/genéticaRESUMEN
Congenital dyserythropoietic anemia type I (CDA-I) is a rare genetic disease that affects erythropoiesis. On the other hand, hemoglobin H (HbH) disease is a severe form of alpha-thalassemia. We herein present ultrastructural and immunocytochemical data concerning the first reported case of congenital anemia with clinical and molecular diagnosis of HbH disease complicated by CDA-I-specific dysplasies of the erythroid cells. Fine structure and transmission electron microscope immunolabeling analysis of the bone marrow and peripheral blood samples were consistent with a potential co-existence of the two defects in the same patient, producing a novel and diagnostically important dyserythropoietic profile. In the patient under investigation both nuclear and plasma membrane of the erythroid cells are almost equally defective. The unknown defect causes the concomitant precipitation of beta- and alpha-globin chains (or hemoglobin), along with an unidentified protein(s). The unusual inclusions gain access to the euchromatin area and exhibit higher affinity for the plasma membrane than the classic inclusions of precipitated alpha- or beta-globin chains seen in thalassemia. The affected erythroid precursors are presented with severe nuclear distortions, endonuclear globin loads, morphological evidence of apoptosis and increased erythrophagocytosis. Plasma membrane distortions and the rate of protein precipitation were aggravated with differentiation. Our findings provide additional evidence for a specific activation of a beta-thalassemic-like mechanism in CDA-I, containing not only the hemoglobin biosynthesis as previously suggested, and interpret the prototypal hematological portrait, which is an HbH disease, modified and partially counterbalanced by the effect of CDA-I or an unidentified CDA-I-like disease. The reported data describe the complexity of the interactions between the CDA-I and the HbH disease, revealing essential pathogenic events of the novel anemia and, indirectly, of the CDA-I.
Asunto(s)
Anemia Diseritropoyética Congénita/patología , Eritrocitos/ultraestructura , Adulto , Anemia Diseritropoyética Congénita/complicaciones , Apoptosis , Células de la Médula Ósea/patología , Células de la Médula Ósea/ultraestructura , Diagnóstico Diferencial , Membrana Eritrocítica/patología , Membrana Eritrocítica/ultraestructura , Eritrocitos/patología , Células Precursoras Eritroides/patología , Células Precursoras Eritroides/ultraestructura , Eritropoyesis , Femenino , Globinas/análisis , Humanos , Inmunohistoquímica , Cuerpos de Inclusión/química , Cuerpos de Inclusión/ultraestructura , Microscopía Inmunoelectrónica , Talasemia alfa/complicaciones , Talasemia alfa/patologíaRESUMEN
In the present paper, we demonstrate the erythroid cell membrane unique properties in a previously characterized case of hemoglobin-H disease, associated with congenital dyserythropoietic anemia type-I features. In order to explain the patient's cell membrane distortions and the high affinity for the various intracellular inclusions, we studied its composition and structure in comparison to other anemic and non-anemic cases. Red cells from peripheral blood were fractionated into cellular, membrane and protein extracts. Membrane attached immunocomplexes were separated and collected by immunoprecipitation. The subcellular fractions were analyzed by SDS-PAGE electrophoresis and immunoblotted against a variety of erythroid-specific antibodies. The protein composition of the membrane was characterized by immunogold electron microscopy. In the membrane of the CDA-associated case, we identified sialic acid and protein deficiencies, formation of protein crosslinkings, excesses of bound globin and immunoglobulins and aberrant peptides. In contrast to the typical hemoglobin-H disease, the ghost-bound globin exhibited preferential attachment to the skeletal proteins than the band 3 and the skeleton-bound globin consisted not only of beta- but also of alpha-globin chains. Another hallmark, probably associated with the CDA defect, was the participation of glycophorins in the membrane-bound immunocomplexes and the pathological clustering of the latter in the membrane. This study strongly suggests that the result of the combinatorial effects on the diseased membrane created a unique profile, quite distinct from the one observed in several typical hemoglobinopathies. Our observations shed light into critical membrane alterations leading to hemolysis in the novel CDA-associated disease and probably into the CDA-I or CDA-I-like diseases.