Two Korean Cases of Hereditary Spherocytosis Caused by Mutations in SLC4A1

Hereditary spherocytosis (HS) is caused by mutations in the SPTA1, SPTB, ANK1, SLC4A1, and EPB42 genes, all of which encode erythrocyte membrane proteins. Mutations in SLC4A1, which encodes band 3 protein, have rarely been reported as the causative factor among Korean patients with HS. Here, we report two Korean patients with HS carrying mutations in SLC4A1. Patient 1 was a 3-year-old girl with unremarkable past and family histories and was evaluated for anemia that was detected after a complete blood count. She was suspected of having HS considering the spherocytosis of her peripheral blood smear, increased osmotic fragility, hemolytic features in blood chemistry tests, and splenomegaly. Sequence analysis revealed that the patient harbored a single heterozygous missense mutation, c.2278C>T (p.Arg760Trp) in exon 17 of SLC4A1. Patient 2 was a 23-year-old man who had a prior history of intermittent jaundice. Although the patient did not have anemia, a genetic test for HS was performed due to evidence of hemolytic features in the blood chemistry test, splenomegaly, and a family history of HS. The test confirmed a single heterozygous missense mutation, c.2423G>T (p.Arg808Leu) in exon 18 of SLC4A1.

Application of High Resolution Melting Curve Analysis in Detection of SLC4A1 Gene Mutation in Patients with Hereditary Spherocytosis / 中国实验血液学杂志

OBJECTIVE@#To investigate the feasibility and clinical significance of high resolution melting(HRM) curve analysis to detect SLC4A1 gene D38A and K56E mutations in the patients with hereditary spherocytosis(HS).@*METHODS@#Peripheral blood was collected from 23 cases of HS for routine tests and their genomic DNA was extracted by routine technique. Specific primers of mutation sites D38A and K56E of SLC4A1 gene were designed. The HRM method was used to analyze all the samples, and then the results of HRM were verified with DNA sequencing technology.@*RESULTS@#Among 23 specimens of HS patients, 6 cases of heterozygous mutant gene were detected by HRM technology, including 3 cases of D38A mutation and 3 cases of K56E mutation, which were confirmed by DNA sequencing.@*CONCLUSION@#The HRM technology can correctly detect 2 common mutation sites including D38A and K56E in SLC4A1 gene in an efficient, fast, and reliable way, which not only can be used for clinical diagnosis, but also expected to be a new method for clinical researchers to define gene mutation spectrum in HS patients.

Esferocitosis hereditaria: experiencia clínica y diagnóstica en Argentina / Hereditary spherocytosis: clinical and diagnostic experience in Argentina / Esferocitose hereditária: experiência clínica e diagnóstica na Argentina

Los objetivos del presente estudio fueron: a) Analizar las características demográficas y clínicas de nuestra población al diagnóstico; b) Evaluar si las pruebas más recientes presentan ventajas sobre las tradicionales; c) Confirmar la frecuencia de las distintas deficiencias de proteínas de membrana; d) Establecer la relación entre severidad y resultado de las pruebas o tipo de deficiencia. Se analizaron 359 individuos estudiados desde 2007, cuando se incorporaron criohemólisis hipertónica (CH), citometría de flujo con eosina-5'- maleimida (5'EMA-CF), FOE por citometría de flujo (FOE-CF) y electroforesis de proteínas de membrana (SDS-PAGE) al estudio de laboratorio clásico, fragilidad osmótica eritrocitaria (FOE) y autohemólisis (AH). Criterios diagnósticos para Esferocitosis Hereditaria (ESH): esferocitos en frotis y dos pruebas positivas. Se identificaron 174 pacientes con ESH y 22 portadores sanos. El 74,9% eran menores de 12 años. La transmisión fue dominante en el 83,1% de los casos. Tuvieron manifestaciones neonatales 89,1%. Las pruebas con mayor sensibilidad fueron CH (92,0%), FOE diferida (91,1%) y 5'EMA-CF (88,5%). En los 125 pacientes en quienes se realizaron CH, 5'EMA-CF y FOE-CF se observó que todos tenían al menos una prueba positiva; 122 (97,6%) tuvieron dos o tres positivas. Las deficiencias más frecuentes fueron ankirina y espectrina. No hubo diferencia en el resultado de las pruebas entre los subgrupos de severidad. Se concluye que las deficiencias más frecuentes en Argentina son ankirina y espectrina, coincidiendo con otras poblaciones latinoamericanas. El uso simultáneo de CH, 5'EMA-CF y FOE-CF permite diagnosticar más del 97% de los casos. La incidencia de manifestaciones neonatales es elevada.

The aims of this study were (a) to assess demographic and clinical aspects of our population at diagnosis; (b) to evaluate diagnostic accuracy of hypertonic cryohemolysis (HC), eosin-5'-maleimide flow cytometry (EMA-FC) and flow cytometric osmotic fragility (OF-FC) in relation to standard screening tests osmotic fragility (OF) and autohemolysis (AH); (c) to confirm the previously reported prevalence of membrane proteins defects; and (d) to assess the relationship between severity of anemia and results of confirmatory tests. Since 2007, the following tests were available in our laboratory: OF, AH, HC, EMA-FC, OF-FC and SDS-PAGE of membrane proteins. Diagnostic criteria for hereditary spherocytosis were spherocytes in blood smear plus ≥2 positive tests. Data from 359 individuals were analyzed: 174 HS patients and 22 silent carriers were detected; 74.9% of patients were less than 12 years old; 83.1% of them showed a dominant inheritance pattern; antecedent of neonatal jaundice/anemia was registered in 89.1%. Tests with higher sensitivity were: HC (92.0%), incubated OF (91.1%), and EMA-FC (88.5%). HC, EMA-FC and OF-FC were simultaneously performed on 125 patients: each of them had at least 1 positive test; 122 (97.6%) had 2 or 3 positive tests. Ankyrin and spectrin were the most frequently found protein deficiencies. Comparison of test results in relation to severity of anemia showed no difference between groups. It can be concluded that compared toother Latin American countries, ankyrin and spectrin were the most frequent protein deficiencies. Simultaneous performing of HC, EMA-FC and OF-FC enabled diagnosing HS in more than 97% of patients. A high incidence of neonatal jaundice/anemia was observed.

Os objetivos do presente estudo foram: a) analisar as características demográficas e clínicas de nossa população ao diagnóstico; b) Avaliar se as provas mais recentes apresentam vantagens sobre as tradicionais; c) Confirmar a frequência das diversas deficiências de proteínas de membrana; d) Establecer a relação entre severidade e resultado das provas ou tipo de deficiência. Foram analisados 359 indivíduos estudados desde 2007, quando se incorporaram crio-hemólise hipertônica (CH), citometria de fluxo com eosina-5'-maleimida (5'EMA-CF), FOE por citometria de fluxo (FOE-CF) e eletroforese de proteínas de membrana (SDS-PAGE) ao estudo de laboratório clássico - fragilidade osmótica eritrocitária (FOE) e auto-hemólise (AH). Critérios diagnósticos para ESH: esferócitos em esfregaço e duas provas positivas. Foram identificados 174 pacientes com ESH e 22 portadores sadios. 74,9% eram menores de 12 anos. A transmissão foi dominante em 83,1%. Tiveram manifestações neonatais 89,1%. As provas com maior sensibilidade foram CH (92,0%), FOE diferida (91,1%) e 5'EMA-CF (88,5%). Nos 125 pacientes aos quais lhes realizaram CH, 5'EMA-CF e FOE-CF se observou que todos tinham no mínimo uma prova positiva; 122 (97,6%) tiveram duas ou três positivas. As deficiências mais frequentes foram anquirina e espectrina. Não houve diferença no resultado das provas entre os subgrupos de severidade. Conclui-se que as deficiências mais frequentes na Argentina são anquirina e espectrina, as quais coincidem com outras populações latinoamericanas. O uso simultâneo de CH, 5'EMA-CF e FOE-CF permite diagnosticar mais de 97% dos casos. A incidência de manifestações neonatais é elevada.

Clinical features of hereditary distal renal tubular acidosis and SLC4A1 gene mutation / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the clinical features of two families with distal renal tubular acidosis (dRTA) and mutations in the pathogenic gene SLC4A1.</p><p><b>METHODS</b>Family investigation, medical history collection, and measurement of biochemical parameters were performed to analyze the clinical phenotype and genetic characteristics of dRTA. Direct sequencing was used to detect SLC4A1 gene mutations.</p><p><b>RESULTS</b>Three patients in these two families (two of them were mother and son) were diagnosed with dRTA with typical clinical features, including short stature, metabolic acidosis, alkaline urine, hypokalemia, and nephrocalcinosis. SLC4A1 gene analysis showed that all the three patients had a pathogenic missense mutation R589H (c.1766G>A). The child in family 1 had a de novo mutation of SLC4A1, and the child in family 2 had an SLC4A1 gene mutation inherited from the mother, which met the characteristic of autosomal dominant inheritance.</p><p><b>CONCLUSIONS</b>This study reports the R589H mutation in SLC4A1 gene in families with hereditary dRTA for the first time in China. Clinical physicians should perform gene detection for patients suspected of hereditary dRTA to improve the diagnosis and treatment of this disease.</p>

Effect of AB serum on human terminal erythroid differentiation ex vivo / 中南大学学报(医学版)

To demonstrate the effect of AB serum on terminal erythroid differentiation ex vivo.
 Methods: After separation of CD34+ cells from cord blood, the cells were cultured and divided into a control group and an experimental group. The effects of AB serum were examined by the expressions of different markers (GPA, Band3 and α4-integrin) for erythroblast differentiation and enucleation by flow cytometry. 
 Results: The CD34+ cells were successfully differentiated to enucleated red blood cells. There were evident differences among the expressions of GPA, Band3 and α4-integrin between the 2 groups. The percentage of GPA positive cells in the experimental group was bigger than that in the control group in every time point. The expression of Band3 in the experimental group was higher than that in the control group. The expression of α4-integrin in the experimental group was lower than that in the control group. In addition, the enucleation rate in the experimental group was higher than that in the control group.
 Conclusion: AB serum can promote the cell differentiation and enucleation during terminal erythroid differentiation in vitro.

Stability of eosin-5'-maleimide dye used in flow cytometric analysis for red cell membrane disorders

BACKGROUND: The eosin-5'-maleimide (EMA) binding test using flow cytometry is a common method to measure reduced mean channel fluorescence (MCF) of EMA-labeled red blood cells (RBCs) from patients with red cell membrane disorders. The basic principle of the EMA-RBC binding test involves the covalent binding of EMA to lysine-430 on the first extracellular loop of band 3 protein. METHODS: In the present study, the MCF of EMA was analyzed for samples derived from 12 healthy volunteers (controls) to determine the stability (i.e., the percentage decrease in fluorescence) of EMA over a period of 1 year. RESULTS: Comparison of periodical MCF readings over time, that is, at 2-month intervals, showed that there were no significant changes in mean channel fluorescence for up to 6 months; however, there was a significant decrease in MCF at 8 months. CONCLUSION: For optimal dye utilization, EMA remained stable only for up to 6 months. Therefore, we recommend reconstitution of the dye every 6 months when implementing this test and storage at -80degrees C in dark conditions.

El antígeno Diego alcanza los 60 años de edad: su descubrimiento y desarrollo / Diego antigen reach 60 years old: discovery and development

El antigeno Diego fue descubierto en junio de 1953 por el hematólogo estadounidense Philip Levine (1900-1987) en una muestra de sangre enviada desde Venezuela por el pediatra Miguel Raga Mendoza (1917-1986). El propósitus, de nombre Diego, había fallecido a los 3 días de edad por causa de una enfermedad hemolítica del recién nacido. Levine bautizó al nuevo antigeno con el nombre de diego y lo clasificó como un factor privado o familiar de baja prevalencia. En 1955, los hematólogos Miguel Layrisse (1919-2002) y Tulio Arents (1918-1990), y el obstetra Rafael Dominguez Sisco (1908-1980) llegaron a la conclusión de que el antígeno Diego tenía una mayor frecuencia que la reportada por Levine y que por tanto constituía un grupo sanguíneo de alta prevalencia en poblaciones indigenas venezolanas. Estos resultados fueron extendidos a otras poblaciones indígenas de América, demostrandose también su existencia en personas de origen asiático (mongoloides) y su ausencia en las razas caucasoide y negroide. El antígeno Diego se transformó así en el primer marcador mongoloide de gran valor antropológico, genético y clínico. En la década de 1990 se demostró que el antígeno Diego estaba asociado con la proteína eritrocitaria denominada banda 3; esta funciona como un intercambiador de aniones (AE-1) que se expresa también en células del túbulo renal. Actualmente, el grupo snguíneo Diego está formado por 22 antígenos o alelos.

On June 1953, the American hematologist Philip Levine (1900-1987) discovered a new erythrocyte antigen in the blood of a sick child collected in Venezuela by the pediatrician Miguel Raga Mendoza (1917-1986). The propositus, named Diego, was affected by a hemolytic disease of the newborn and died 3 days after delivery. Levine named the antigen Diego (Diª) and classified it as a private or familial factor of low prevalence. In 1955, the hematologists Miguel Layrisse (1919-2002) and Tulio Arends (1918-1990), and the obstetrician Rafael Dominguez Sisco (1908-1980) concluded that the Diego antigen had a greater frecuency than that reported by Levine, constituting a blood group of high prevalence in Venezuelan aboriginal populations. Similar results were obtained in other aboriginal populations of the American continent. The Diego antigen was also present in high frequency in people of asiatic origin (mongoloids), and absent in caucasoid and negroid people. Thus, the Diego antigen became the first mongoloid marker of great anthropological, genetic and clinical importance. In 1992, the Diego antigen was found associated with the erythrocyte protein named band 3, later known to function as an anion exchanger (AE-1). Band 3 is also expressed on cells of the renal tubules. Presenthy, the Diego blood group is formed by 22 antigens or allelles.

Retroperitoneal laparoscopic radical nephrectomy in the treatment of renal cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the safety and efficacy of retroperitoneal laparoscopic radical nephrectomy in the treatment of renal cancer.</p><p><b>METHODS</b>The clinical data of 53 cases who underwent retroperitoneal laparoscopic radical nephrectomy were analyzed retrospectively.</p><p><b>RESULTS</b>Fifty-two cases achieved successful retroperitoneal laparoscopic radical nephrectomy, a conversion to open surgery was required in one case because of severe adhesion. The operation time was 75 min to 220 min (mean, 125 min), the blood loss was 50 ml to 420 ml (mean, 120 ml), and the postoperative hospital stay was 6 d to 12 d. Complications occurred in 4 cases. Pathological examination showed that 47 cases were of renal clear cell carcinoma, 5 of chromophobe carcinoma, and 1 of cystic renal cell carcinoma. Follow-up for 1 month to 5 years showed no tumor recurrence and metastasis.</p><p><b>CONCLUSION</b>Retroperitoneal laparoscopic radical nephrectomy is a safe and effective treatment for patients with stage T1 - 2N0M0 renal cell carcinoma.</p>

Molecular Approach for Distal Renal Tubular Acidosis Associated AE1 Mutations

The molecular approaches to distal renal tubular acidosis (dRTA) associated AE1 mutations lead us to understand the genetic and pathophysiological aspects of the acidification defects. An unanticipated high value of the urine-blood (U-B) PCO2 after NaHCO3 loading observed in a case of dRTA and southeast Asian ovalocytosis (SAO) might be from a mistarget of the AE1 to the luminal membrane of type A intercalated cells. The mutations of the AE1 gene resulted in SAO and also affected renal acidification function. Notwithstanding, after the NH4Cl loading in 20 individuals with SAO, the acidification in the distal nephron was normal. The presence of both SAO and G701D mutations of AE1 gene would explain the abnormal urinary acidification in the patients with the compound heterozogosity. In terms of the effect of the mutations on trafficking of AE1, truncated kidney isoform (kAE1) of wild-type showed a 'dominant-positive effect' in rescuing the recessive mutant kAE1 (S773P or G701D) trafficking to the plasma membrane, in contrast with the dominant mutant kAE1 (R589H) resulting in a 'dominant-negative effect' when heterodimerized with the wild-type kAE1. It is notable that the dominant mutants kAE1 (R901X or G609R) expression in MDCK cells clearly results in aberrant surface expression with some mutant protein appearing at the apical membrane. These might result in net bicarbonate secretion and increasing U-B PCO2 in the distal nephron. The molecular physiological and genetic approaches have permitted identification of the molecular defects, predominantly in transporter proteins, and should in turn prompt development of novel therapeutic strategies.

Ensayo inmunoenzimático para la determinación de anticuerpos naturales anti banda 3 / Immunoenzimatic assay to determine the natural anti-band 3 antibodies

Se estandarizó un método inmunoenzimático (ELISA) para la determinación de anticuerpos naturales anti banda 3 acoplando a placas Chemobond la proteína banda 3 obtenida a partir de la membrana de eritrocitos humanos mediante una combinación de cromatografía de intercambio aniónico y afinidad. Se emplearon 3 mg de la proteína banda 3 por pozo, lográndose un nivel de detección de 1 mg/mL de anticuerpo anti banda 3. Los resultados indican la utilidad del método para su empleo en la medición de los niveles de anticuerpos naturales anti banda 3 en pacientes con drepanocitosis, tanto en estado basal como en las crisis vasooclusivas dolorosas.

An immunoenzimatic assay (ELISA) was standardized to determine the natural anti-band 3 antibodies by coupling with Chemobond plates the band 3 protein obtained from the membrane of human erythrocytes by a combination of affinity and anion exchange chromatography. 3 g of band 3 protein per well were used. A level of detection of 1 g/mL of anti-band 3 antibody was achieved. The results showed the usefulness of the method to measure the levels of natural anti-band 3 antibodies in patients with drepanocytes, both in basal state and in the painful vasocclusive crises.

Inflammatory myofibroblastic tumor of bladder: a clinicopathologic study of five cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathologic features, diagnosis and differential diagnosis of inflammatory myofibroblastic tumor of the urinary bladder.</p><p><b>METHODS</b>Excisional specimens from 5 cases of vesical inflammatory myofibroblastic tumor were studied by light microscopy and immunohistochemistry (EnVision). The clinical data were also analyzed.</p><p><b>RESULTS</b>Among the 5 patients studied, 3 were males and 2 were females. The age of the patients ranged from 10 to 53 years (mean age = 35 years). The most common clinical presentation was micturition pain and hematuria. Three cases were located at the dome of the urinary bladder and the remaining 2 cases were found in the left lateral wall. Histologically, the tumor varied from myxoid to highly cellular. The tumor cells were spindle to stellate in shape, widely separated or showed a compact fascicular pattern. There were often associated with mixed inflammatory infiltrates and an irregular meshwork of small dilated vessels. Immunohistochemical study showed that the tumor cells expressed AE1/AE3 (5/5), vimentin (5/5), smooth muscle actin (5/5), calponin (5/5), caldesmon (3/5), desmin (4/5) and anaplastic lymphoma kinase protein (4/5). Follow-up data were available in 4 patients and none had local recurrence or died of this disease.</p><p><b>CONCLUSION</b>Inflammatory myofibroblastic tumour of urinary bladder is a rarely encountered but distinctive neoplasm with intermediate malignant potential.</p>

Immunolocalization of anion exchanger 1 (Band 3) in the renal collecting duct of the common marmoset

The purpose of this study was to determine the expression and distribution of band 3 in the collecting duct and connecting tubules of the kidney of the marmoset monkey (Callithrix jacchus), and to establish whether band 3 is expressed in type A intercalated cells. The intracellular localization of band 3 in the different populations of intercalated cells was determined by double-labeling immunohistochemistry. Immunohistochemical microscopy demonstrated that band 3 is located in the basolateral plasma membranes of all type A intercalated cells in the connecting tubule (CNT), cortical collecting duct (CCD), and outer medullary collecting duct (OMCD) of the marmoset. However, type B intercalated cells and non-A/ non-B intercalated cells did not show band 3 labeling. Electron microscopy of the CNT, CCD and OMCD confirmed the light microscopic observation of the basolateral plasma membrane staining for band 3 in a subpopulation of interacted cells. Basolateral staining was seen on the plasma membrane and small coated vesicles in the perinuclear structure, some of which were located in the Golgi region. In addition, there was no labeling of band 3 in the mitochondria of the CNT, CCD and in OMCD cells. The intensity of the immunostaining of the basolateral membrane was less in the CNT than in the CCD and OMCD. In contrast, band 3 immunoreactivity was greater in the intracellular vesicles of the CNT. From these results, we suggest that the basolateral Cl-/HCO3- exchanger in the monkey kidney is in a more active state in the collecting duct than in the CNT.

Andálisis de los polimorfismos G199A, NcoI del gen ANK1 y Memphis I del gen SLC4A1 en individuos sanos y pacientes mexicanos con esferocitosis hereditaria / Polymorphism analysis of G199A, Ncol in ANK1 and Memphis I in SLC4A1 genes in Mexican healthy individuals and subjects affected with hereditary spherocytosis

Antecedentes. En México la esferocitosis hereditaria (EH) es la causa principal de anemia hemolítica hereditaria y se debe a mutaciones en uno o más genes implicados en la membrana eritrocitaria, lo que dificulta la identificación del gen primario. Objetivo. Con el fin de valorar la utilización de los polimorfismos G199A y NcoI del gen ANK1, y Memphis I del gen SLC4A1 como marcadores genéticos para identificar esta enfermedad, estimamos sus frecuencias alélicas y genotípicas en 45 muestras de ADN de pacientes con EH y 28 de individuos sanos, las cuales fueron similares en uno y otro grupos para los polimorfismos G199A y Memphis I, con baja frecuencia de heterocigotos, lo que limita su utilidad como marcador genético. Resultados. El polimorfismo NcoI no mostró diferencias alélicas y genotípicas en los grupos de estudio, pero sí mayor frecuencia de heterocigotos (0.49 y 0.43 en enfermos y sanos respectivamente), característica que le confiere ventajas para ser utilizado como marcador genético en familias con EH. Conclusiones. Finalmente, debido a que existen otros genes implicados en la patología molecular de la EH, consideramos que es necesario analizar otros polimorfismos de genes que codifican para las proteínas involucradas en las deficiencias que conducen a esferocitosis hereditaria en la población mexicana.

BACKGROUND: In Mexico, Hereditary Spherocytosis (HS) is the main cause of hereditary hemolytic anemia, due to mutations of one or more genes involved in the erythrocyte membrane, making it difficult to identify the primary gene. OBJECTIVE: With the purpose of estimating the use of the polymorphisms G199A and NcoI of ANK1 gene, and Memphis I of SLC4A1 gene, as genetic markers to screen this disease, we searched the allelic and genotypic frequencies in 45 DNA samples of HS patients and 28 from healthy individuals. RESULTS: Allelic and genotypic frequencies were similar in both studied groups for the G199A and Memphis I polymorphisms, with low frequency of heterozygosis showing its limited use as a genetic marker. The allelic and genotypic frequencies of the NcoI polymorphism were also similar in both groups, however a higher heterozygote frequency was observed (0.49 and 0.43 in patients and healthy individuals), a feature that may turn it into a useful genetic marker. CONCLUSIONS: Since there are other genes implicated in the molecular pathology of the HS, we consider it necessary to continue analyzing other polymorphisms of the genes involved in Hereditary Spherocytosis among the Mexican population.

Analysis of the interaction between human kidney anion exchanger 1 and kanadaptin using yeast two-hybrid systems

Kidney anion exchanger adaptor protein (Kanadaptin) is a protein which interacts with the cytoplasmic N-terminal domain of kidney anion exchanger 1 (kAE1) and was first detected in mice using the yeast two-hybrid system and was also found to co-localize with kAE1 in rabbit a-intercalated cells. Impaired trafficking of human kAE1 can result in the kidney disease-distal renal tubular acidosis (dRTA), and defective interaction between human kAE1 and kanadaptin may cause this trafficking impairment and be the basis for dRTA pathogenesis. However, it is unknown whether kAE1 can really interact with kanadaptin in humans. We have thus investigated the interaction between human kAE1 and human kanadaptin by using both Gal4 and LexA yeast two-hybrid systems. It was found that co-expression of Gal4DBD fused to the cytoplasmic N-terminal domain of kAE1 and Gal4AD fused to kanadaptin could not activate the transcription of the ADE2, HIS3 and lacZ reporters in the Gal4 system. A similar result was obtained for the interaction between B42AD fused to the cytoplasmic N-terminal domain of kAE1 and LexA fused to kanadaptin in activation of lacZ transcription in the LexA system. The absence of interaction between the fusion proteins in both yeast two-hybrid systems raises the possibility that kAE1 may not interact with kanadaptin in human cells. Considerably different structures of both kAE1 and kanadaptin in mice and humans may lead to different binding properties of the proteins in these two species.

Organización de la membrana celular: banda 3, estructura y función / Organization of the cellular membrane: band 3, structure and function

El término banda 3 se refiere a un grupo de intercambiadores aniónicos (AE 0-3), que están presentes en la membrana de todas las células y organelos celulares, y que participan en diversas actividades fisiológicas, entre las que se destacan el intercambio bicarbonato/ cloruro, unión de IgG y remoción celular y el mantenimiento de la integridad celular. El AE 1 constituye el elemento central integral de un macrocomplejo proteico en el contexto de la organización de la membrana del eritrocito, que está constituido por 3 dominios con funciones estructurales y metabólicas específicas. Cambios estructurales de la banda 3 y la presencia de autoanticuerpos naturales anti banda 3 se han asociado con el envejecimiento celular y la generación del antígeno de senescencia celular (ASC). Se analiza el mecanismo de envejecimiento prematuro de los eritrocitos SS en la drepanocitosis a partir de la auto-oxidación aumentada de la hemoglobina, que trae como consecuencia alteraciones en la banda 3 y expresión del ASC, unión de IgG y la remoción de los eritrocitos SS mediante fagocitosis. Alteraciones en banda 3 se han observado también en enfermedades neurológicas como el Alzheimer, disquinesia idiopática familiar, epilepsias idiopáticas, así como en enfermedades cardiovasculares, señalándose la elevada mortalidad en el neonato con deficiencia total de banda 3

Función de los anticuerpos naturales anti banda 3 en el fenómeno de vasooclusión de la drepanocitosis / Function of the natural anti-band 3 antiodies in the phenomenon of drepanocytosis vasoocclusion

La vasooclusión en la drepanocitosis se considera una característica única entre las anemias hemolíticas, y aún cuando se han logrado avances en su conocimiento, las bases de su control y prevención permanecen parcialmente desconocidas. La idea de que el eritrocito falciforme induce el proceso vasooclusivo ha sido descartada, y no existe duda en la actualidad de que el fenómeno ocurre debido a la adhesión al endotelio de eritrocitos SS oxigenados, no deformados, al endotelio de las venas postcapilares, donde participan un número de moléculas de adhesión, presentes tanto en los eritrocitos SS como en el endotelio vascular, factores plasmáticos y un elemento de creciente importancia: la molécula banda 3 eritrocitaria (AE 1). La AE 1 forma parte de una familia de intercambiadores aniónicos (AE 0-3) presentes en todas las células y organelos celulares, que constituyen la proteína central integral de un macrocomplejo en la membrana del eritrocito. Producto de la auto-oxidación de la Hb S, la molécula AE 1 se agrega en la superficie del eritrocito SS y adquiere naturaleza adhesiva, que se reconocen por anticuerpos naturales de la clase IgG. Se destaca la importancia del control de los niveles de anticuerpos naturales anti banda 3, lo que pudiera confirmar o rechazar la idea de si la adhesión de los eritrocitos SS y posterior vasooclusión es el resultado de alteraciones en los niveles de los mencionados anticuerpos. Se analizan las potencialidades terapéuticas del estudio de la molécula banda 3 y los anticuerpos naturales anti banda 3 en la drepanocitosis

Clinicopathologic and immunohistochemical study of pulmonary epithelioid hemangioendothelioma / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinical and pathological characteristics of pulmonary epithelioid hemangioendothelioma.</p><p><b>METHODS</b>Four cases of pulmonary epithelioid hemangioendothelioma were studied by histopathologic and immunohistochemical examination of lung biopsy specimens.</p><p><b>RESULTS</b>There were 3 female and 1 male, age 28 to 40 years. Clinically the tumor presented as multiple bilateral small nodules in the lung. Histologically, crown-like clusters of epithelioid tumor cells were obtained which filled in the alveoli locating at the periphery of the tumor nodules, while the central part of the nodules contained myxoid to hyaline matrix. The overall architecture of the lung was still preserved. Additionally, intracytoplasmic vacuoles were seen in tumor cells within which red blood cells were sometimes identified. Tumor cells generally lacked pleomorphism, mitotic activity and necrosis. They were immunohistochemically positive for CD31 and CD34. AE1/AE3 staining was positive in some cases.</p><p><b>CONCLUSIONS</b>Pulmonary epithelioid hemangioendothelioma often occurs in a middle-aged woman and represents a distinct clinical pathological entity.</p>

Ectopic hamartomatous thymoma: a clinicopathological and immunohistochemical study of two cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathological and immunohistochemical features of ectopic hamartomatous thymoma (EHT), and to discuss its histogenesis.</p><p><b>METHODS</b>The clinical and pathologic features of two EHT cases of were evaluated. Immunohistochemical study was performed by LSAB method using a panel of antibodies including AE1/AE3, CK5, CK7, CK8, CK20, EMA, vimentin, CD5, CD10, alpha-SMA, calponin, desmin, CD34, S-100 protein, CD57, GFAP, TTF-1 and CD99.</p><p><b>RESULTS</b>Both cases occurred in males aged 20 years and 40 years respectively. Each patient presented with a solitary mass, one located in the suprasternal fossa and the other in the left supraclavicular region for a period of 6 months and 2 months respectively. Grossly, the masses were well-circumscribed with spherical and ovoid appearance, measuring 5 cm and 3 cm in maximum diameter respectively. On cut section, they were gray-white in color and of soft consistency. Histologically, both tumors were composed of a mixture of spindle cells, epithelial cells and mature adipose tissue. The spindle cells element accounted 85% and 70% each in the two cases. They resembled fibroblasts in morphology and were arranged frequently in fascicular, woven or storiform patterns. Epithelial cells element represented nearly 10% in both cases. Most of the epithelial cells had a non-keratinization squamous appearance. They formed small solid islands and adamantinoma-like "nastomosing cords", or appeared as lining cells in large cystic spaces. In focal areas, glandular differentiation presented as small glands. A transition between the spindle cell and epithelium components could be also identified in some areas. Mature adipose tissue was irregularly distributed in the two tumors, about < 5% and 20% respectively. Immunohistochemically, the epithelial element expressed AE1/AE3, CK5, CK7, CK8 and EMA, whereas the spindle component expressed AE1/AE3, CK5, CK7, CK8, vimentin, CD10, CD34, alpha-SMA, MSA, and calponin. Both elements were negative for CK20, TTF-1, desmin, S-100 protein, CD57, GFAP and CD99.</p><p><b>CONCLUSIONS</b>EHT is a benign tumor that occurs predominantly in the lower neck region of young to middle-aged males. Immunohistochemical study revealed myoepithelial differentiation of the spindle cells, suggesting EHT is a mixed tumor composed of epithelial and myoepithelial cells. EHT possibly originates from the remnants of cervical sinus of His, and therefore, may be renamed as branchial anlage mixed tumor.</p>