Determination of ochratoxin A in coffee by ELISA method and its relationship with the physical, physicochemical and microbiological properties / Determinación de ocratoxina A en café mediante método ELISA y su relación con las propiedades físicas, fisicoquímicas y microbiológicas

Background: Coffee is one of the most consumed beverages in the world; however, it may contain toxic compounds such as ochratoxin A (OTA). Objectives: Determine the OTA's presence in different types of coffee, intended for beverage preparation and marketed in Colombia through the application of the enzyme-linked immunosorbent assay (ELISA) and analyze its relationship with the physical, physicochemical and microbiological properties. Methods: 8 samples of coffee commercialized in the Colombian market were selected, in which the OTA content was determined by applying the ELISA method. Likewise, a microbiological analysis was performed, and physicochemical properties were determined, such as moisture content, aw, percentage total dissolved solids (%TDS), and extraction yield (%EY). Physical properties such as free-flow densities, compacted bulk densities (CBD), porosity, average particle size (ASP), and color. The data were treated with multivariate analysis using Principal Component Analysis (PCA) and Cluster Analysis (CA) to quantitatively investigate the relationships between the coffee samples concerning their physical, physicochemical properties, and OTA content. LSD test was applied with a significance level of 95 % and Pearson correlation test. Results:All the samples had OTA content, but only 2 exceeded the limits allowed by the regulations, with a maximum value of 15.449 µg/Kg, which represents 31.449 % of the tolerable daily intake according to the parameters defined by Joint FAO/WHO Expert Committee on Food Additives (JECFA). According to the PCA and CA, the samples were grouped harmonically according to the type of coffee associated with its commercial presentation and industrial process, OTA content, and ASP. OTA content was significantly and positively correlated (p< 0.05) with %EY, %TDS, ASP, porosity, CBD and moisture. Conclusions: The coffees marketed in Colombia showed a variable range of OTA, where soluble coffees had higher OTA contents than roasted coffees, and 25 % of the coffees analyzed do not meet the levels defined by Colombian regulations. The OTA content in coffee is related to properties that define the ability to extract solutes from coffee

Antecedentes: El café es una de las bebidas más consumidas en el mundo, sin embargo, puede contener compuestos tóxicos como la ocratoxina A (OTA). Objetivos: Determinar la presencia de OTA en diferentes tipos de café destinados a la preparación de bebida y comercializados en Colombia mediante la aplicación del ensayo inmunoabsorbente ligado a enzimas (ELISA) y analizar su relación con las propiedades físicas, fisicoquímicas y microbiológicas. Métodos: Se seleccionaron 8 muestras de café comercializado en el mercado colombiano, en las cuales se determinó el contenido de OTA mediante la aplicación del método ELISA. Así mismo se realizó análisis microbiológico y se determinaron propiedades fisicoquímicas como contenido de humedad, aw, porcentaje de sólidos disueltos totales (%TDS) y rendimiento de extracción (%EY); y propiedades físicas como densidad por caída libre, densidad compactada (CBD), porosidad, tamaño promedio de partícula (ASP) y color. Los datos fueron tratados con análisis multivariado empleando análisis de componentes principales (PCA) y análisis de conglomerados (CA) para investigar cuantitativamente las relaciones entre las muestras de café con respecto a sus propiedades físicas, fisicoquímicas y contenido de OTA. Se aplicó prueba LSD con un nivel de significación del 95 % y prueba de correlación de Pearson. Resultados: Todas las muestras presentaron contenido de OTA, pero solo 2 sobrepasaron los límites permitidos por la normatividad, con un valor máximo de 15.449 µg/Kg, el cual representa un 31.449 % de la ingesta diaria tolerable según los parámetros definidos por el Comité Mixto FAO/OMS de Expertos en Aditivos Alimentarios (JECFA). De acuerdo al PCA y CA, las muestras se agruparon armónicamente de acuerdo al tipo de café asociado a su presentación comercial y proceso industrial, contenido de OTA y ASP; el contenido de OTA se correlacionó significativa y positivamente (p < 0.05) con el %EY, %TDS, ASP, porosidad, CBD y humedad. Conclusión: Los cafés comercializados en Colombia presentan un rango variable de OTA, en donde los cafés solubles presentan contenidos de OTA mayores que los cafés tostados y el 25 % de los cafés analizados no cumplen con niveles definidos por la normatividad colombiana. El contenido de OTA en el café está relacionado con propiedades que definen la capacidad de extracción de solutos del café

Transferrina y ceruloplasmina en orina de pacientes con lupus eritematoso sistémico. ¿Son útiles para diferenciar pacientes con nefritis lúpica? / Utility of urinary transferrin and ceruloplasmin in patients with systemic lupus erythematosus for differentiating patients with lupus nephritis

ANTECEDENTES Y OBJETIVO: El diagnóstico de la nefritis lúpica (NL) se suele hacer con la biopsia renal, que es una técnica invasiva que conlleva múltiples riesgos. Por lo tanto, han surgido diferentes biomarcadores en orina como posibles alternativas para el diagnóstico de la NL. Sin embargo, los estudios de biomarcadores en orina de pacientes latinoamericanos con lupus eritematoso sistémico (LES) son escasos; por lo tanto, el objetivo del presente estudio fue determinar el valor diagnóstico de la transferrina (TF) y la ceruloplasmina (CP) en orina, para diferenciar los pacientes que tienen compromiso renal de aquellos que no. MATERIALES Y MÉTODOS: Se incluyeron prospectivamente pacientes con diagnóstico de LES de acuerdo a los criterios del American College of Rheumatology (ACR). Se excluyeron los pacientes con otra enfermedad autoinmune concomitante, infección activa (de vías urinarias o sistémica), terapia de reemplazo renal, infección por virus de la inmunodeficiencia humana y embarazo. A cada paciente se le tomó una muestra de orina. El diagnóstico de NL se realizó mediante los criterios ACR para la definición de NL. La actividad y la cronicidad de la NL en la biopsia renal fueron medidas con el índice de Austin. La determinación de los niveles de TF y CP se realizó con kits comerciales de ELISA. Se utilizó la prueba t de Student y la prueba U de Mann Whitney para comparar los datos. Para determinar las asociaciones entre las variables se utilizaron los coeficientes de correlación de Spearman. Por último, se construyeron curvas ROC. RESULTADOS: Se incluyeron 120 pacientes con LES, de los cuales el 85% fueron de sexo femenino. El 76% fueron de raza mestiza. Presentaron una edad media de 32,8+/-12,1años, y una media del SLEDAI de 8,4+/-8,9, y un 64% presentaron compromiso renal. Los niveles de ambos biomarcadores fueron significativamente mayores en pacientes con NL comparados con aquellos sin NL. De igual manera, los niveles de ambos biomarcadores fueron significativamente mayores en pacientes con NL activa comparados con aquellos con NL inactiva. Los niveles de TF fueron significativamente mayores en pacientes afro-latinoamericanos. Por otro lado, las concentraciones de TF se correlacionaron con el SLEDAI y el rango de proteinuria, y las concentraciones de TF y CP se correlacionaron entre sí. Las curvas ROC para ambos biomarcadores mostraron un buen valor diagnóstico de la NL. CONCLUSIONES: En nuestra cohorte de pacientes con LES encontramos que la TF y la CP son potenciales biomarcadores para el diagnóstico de la NL e, incluso, de la actividad de la NL

BACKGROUND AND OBJECTIVE: Diagnosis of lupus nephritis (LN) is usually based on renal biopsy, which is an invasive technique that involves multiple risks. Therefore, different biomarkers have emerged as alternatives for the diagnosis of LN. Nonetheless, studies regarding urinary biomarkers in Latin American patients are limited. The objective of this study was to assess the diagnostic value of urinary transferrin and ceruloplasmin to differentiate patients who have renal involvement from those who do not. MATERIALS AND METHODS: Systemic lupus erythematosus (SLE) patients that met the revised American College of Rheumatology (ACR) classification criteria were recruited. Patients with another autoimmune disease, active infection (urinary tract or systemic infection), renal replacement therapy, human immunodeficiency virus infection or pregnancy were excluded. A urine sample was collected from each patient. LN was diagnosed according to ACR criteria. The activity and chronicity of LN were measured using the Austin indices. Urinary transferrin and ceruloplasmin levels were measured using commercial enzyme-linked immunosorbent assay (ELISA) kits. Mann-Whitney U test and Student's t-test were used to compare data. Spearman's rank correlation was used to determine associations. Lastly, receiver operating characteristic (ROC) curves were created. RESULTS: The study involved 120 SLE patients. In all, 85% were female, 76% mestizo, the mean age was 32.8+/-12.1years and mean systemic lupus erythematosus disease activity index (SLEDAI) was 8.4+/-8.9; 64% had renal involvement. Urinary levels of the two biomarkers were significantly higher in patients with LN compared to those without LN. Similarly, urinary levels of both biomarkers were significantly higher in patients with active LN compared to those with inactive LN. Furthermore, urinary transferrin levels were significantly higher in Afro-Latin American patients. On the other hand, urinary transferrin levels correlated with SLEDAI and proteinuria, and transferrin and ceruloplasmin levels correlated with each other. The diagnostic value of ROC curves for these urinary biomarkers for LN were good. CONCLUSIONS: In our cohort of SLE patients, we found that transferrin and ceruloplasmin were potential biomarkers for LN, and can even differentiate active LN

Induction of NF-κB inflammatory pathway in monocytes by microparticles from patients with systemic lupus erythematosus.

BACKGROUND: Elevated levels of circulating microparticles (MPs) and molecules of the complement system have been reported in patients with systemic lupus erythematosus (SLE). Moreover, microparticles isolated from patients with SLE (SLE-MPs) contain higher levels of damage-associated molecular patterns (DAMPs) than MPs from healthy controls (CMPs). We hypothesize that the uptake of MPs by monocytes could contribute to the chronic inflammatory processes observed in patients with SLE. Therefore, the aim of this study was to evaluate the expression of activation markers, production of proinflammatory mediators, and activation of the NF-κB signaling pathway in monocytes treated with CMPs and SLE-MPs. METHODOLOGY: Monocytes isolated from healthy individuals were pretreated or not with pyrrolidine dithiocarbamate (PDTC) and cultured with CMPs and SLE-MPs. The cell surface expression of CD69 and HLA-DR were evaluated by flow cytometry; cytokine and eicosanoid levels were quantified in culture supernatants by Cytokine Bead Array and ELISA, respectively; and the NF-κB activation was evaluated by Western blot and epifluorescence microscopy. RESULTS: The cell surface expression of HLA-DR and CD69, and the supernatant levels of IL-6, IL-1ß, PGE2, and LTB4 were higher in cultures of monocytes treated with SLE-MPs than CMPs. These responses were blocked in the presence of PDTC, a pharmacological inhibitor of the NF-κB pathway, with concomitant reduction of IκBα and cytoplasmic p65, and increased nuclear translocation of p65. CONCLUSIONS: The present findings indicate that significant uptake of SLE-MPs by monocytes results in activation, production of inflammatory mediators, and triggering of the NF-κB signaling pathway.

Utility of urinary transferrin and ceruloplasmin in patients with systemic lupus erythematosus for differentiating patients with lupus nephritis. / Transferrina y ceruloplasmina en orina de pacientes con lupus eritematoso sistémico. ¿Son útiles para diferenciar pacientes con nefritis lúpica?

BACKGROUND AND OBJECTIVE: Diagnosis of lupus nephritis (LN) is usually based on renal biopsy, which is an invasive technique that involves multiple risks. Therefore, different biomarkers have emerged as alternatives for the diagnosis of LN. Nonetheless, studies regarding urinary biomarkers in Latin American patients are limited. The objective of this study was to assess the diagnostic value of urinary transferrin and ceruloplasmin to differentiate patients who have renal involvement from those who do not. MATERIALS AND METHODS: Systemic lupus erythematosus (SLE) patients that met the revised American College of Rheumatology (ACR) classification criteria were recruited. Patients with another autoimmune disease, active infection (urinary tract or systemic infection), renal replacement therapy, human immunodeficiency virus infection or pregnancy were excluded. A urine sample was collected from each patient. LN was diagnosed according to ACR criteria. The activity and chronicity of LN were measured using the Austin indices. Urinary transferrin and ceruloplasmin levels were measured using commercial enzyme-linked immunosorbent assay (ELISA) kits. Mann-Whitney U test and Student's t-test were used to compare data. Spearman's rank correlation was used to determine associations. Lastly, receiver operating characteristic (ROC) curves were created. RESULTS: The study involved 120 SLE patients. In all, 85% were female, 76% mestizo, the mean age was 32.8±12.1years and mean systemic lupus erythematosus disease activity index (SLEDAI) was 8.4±8.9; 64% had renal involvement. Urinary levels of the two biomarkers were significantly higher in patients with LN compared to those without LN. Similarly, urinary levels of both biomarkers were significantly higher in patients with active LN compared to those with inactive LN. Furthermore, urinary transferrin levels were significantly higher in Afro-Latin American patients. On the other hand, urinary transferrin levels correlated with SLEDAI and proteinuria, and transferrin and ceruloplasmin levels correlated with each other. The diagnostic value of ROC curves for these urinary biomarkers for LN were good. CONCLUSIONS: In our cohort of SLE patients, we found that transferrin and ceruloplasmin were potential biomarkers for LN, and can even differentiate active LN.

Poly(acrylic acid)-Coated Iron Oxide Nanoparticles interact with mononuclear phagocytes and decrease platelet aggregation.

Poly(acrylic acid)-Coated Iron Oxide Nanoparticles (PAC-IONs) did not compromise the viability of mononuclear cells and potentially interact with cells through scavenger receptors. This study evaluated: 1) The capacity of the PAC-IONs to induce platelet activation and aggregation, and 2) The effect of the PAC-IONs in two functions of Monocyte-Derived Macrophages (MDMs) when differentiated in their presence; that is, the removal of apoptotic cells (ACs) and the levels of cytokines induced by Lipopolysaccharide (LPS) and the ACs. The PAC-IONs did not affect the platelet activation but antagonized their aggregation. On the other hand, the differentiation of MDMS in the presence of PAC-IONs did not inhibit the ability of these cells to phagocytose latex beads but decreased the number of apoptotic bodies internalized by them. MDMs differentiated in the presence of PAC-IONs and stimulated with LPS or ACs exhibited an overall decrease of the cytokine levels. The altered synthesis of cytokines could be attributed to a high production of Reactive Oxygen Species (ROS) caused by the increase in the intracellular iron content. The effect of the PAC-IONs on the cell cycle of U937 and Jurkat cells was also studied; there was not either cell accumulation in any phase of the cell cycle or changes in the DNA content. It is clear that PAC-IONs affect neither the viability nor compromise some cellular functions. However, they could alter the functioning of the immune system; therefore, in the case of being used as a diagnostic tool, their permanence in the body should be considered.

Altered recruitment of Lyn, Syk and ZAP-70 into lipid rafts of activated B cells in Systemic Lupus Erythematosus.

There is evidence that B cells from patients with Systemic Lupus Erythematosus (SLE) could be hyperactivated due to changes in their lipid rafts (LR) composition, leading to altered BCR-dependent signals. This study aimed to characterize possible alterations in the recruitment of protein tyrosine kinases (PTK) into B cells LR from SLE patients. Fifteen patients with SLE and ten healthy controls were included. Circulating B cells were isolated by negative selection and stimulated with goat Fab´2 anti-human IgM/IgG. LR were isolated with a non-ionic detergent and ultracentrifuged on 5-45% discontinuous sucrose gradients. Proteins from each fraction were analyzed by Western Blot. Total levels of Lyn, Syk, and ZAP-70 in resting B cells were similar in SLE patients and healthy controls. Upon BCR activation, Lyn, Syk and ZAP-70 recruitment into LR increased significantly in B cells of healthy controls and patients with inactive SLE. In contrast, in active SLE patients there was a great heterogeneity in the recruitment of signaling molecules and the recruitment of ZAP-70 was mainly observed in patients with decreased Syk recruitment into LR of activated B cells. The reduction in Flotilin-1 and Lyn recruitment in SLE patients seem to be associated with disease activity. These findings suggest that in SLE patients the PTK recruitment into B cell LR is dysregulated and that B cells are under constant activation through BCR signaling. The decrease of Lyn and Syk, the expression of ZAP-70 by B cells and the increase in Calcium fluxes in response to BCR stimulation in active SLE patients, further support that B cells from SLE patients are under constant activation through BCR signaling, as has been proposed.

Blood-brain barrier disruption and neuroinflammation as pathophysiological mechanisms of the diffuse manifestations of neuropsychiatric systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disease that can involve nervous system commitment known as neuropsychiatric systemic lupus erythematosus (NPSLE). The diagnostic of NPSLE is complex because the symptoms range from focal symptoms (e.g., strokes, thrombotic events) to diffuse disorders affecting cognition, mood and level of consciousness (e.g. acute confusional state, psychosis). Both type of manifestations of NPSLE differ in their pathological mechanisms. The focus of this review will be on the mechanisms that lead to the blood-brain barrier (BBB) disruption and to the neuroinflammation related with the diffuse manifestations of NPSLE.

Identification of Levels of Serum Amyloid A and Apolipoprotein A1 in Serum Proteomic Analysis of Neuropsychiatric Systemic Lupus Erythematosus Patients.

Neuropsychiatric Systemic Lupus Erythematosus (NPSLE) has multiple pathogenic mechanisms that cause diverse manifestations and whose diagnosis is challenging because of the absence of appropriate diagnostic tests. In the present study the application of proteomics using two-dimensional electrophoresis (2D) and mass spectrometry (MS) allowed the comparison of the protein profile of the serum low and high abundance protein fractions of NPSLE patients (NPSLE group) and SLE without neuropsychiatric syndromes (SLE group), Neuropsychiatric syndromes not associated with SLE (NPnoSLE groups), and healthy controls (CTRL group). The gels obtained were digitalized and analyzed with the PDQuest software. The statistical analysis of the spots was performed using the nonparametric Kruskal Wallis and Dunn's multiple comparison tests. Two spots showed significant differences and were identified by MS. Spot 4009 was significantly lower in NPSLE with regard to NPnoSLE (p= 0,004) and was identified as apolipoprotein A1 (APOA1) (score 809-1132). Spot 8001 was significantly higher in NPSLE regarding CTRL and NPnoSLE (p= 0,01 y 0,03, respectively) and was identified as serum amyloid A (SAA) (score 725-2488). The proinflammatory high density lipoproteins (HDL) have been described in SLE. In this HDL the decrease of APOA1 is followed by an increase in SAA. This altered level of both proteins may be related to the inflammatory state that is characteristic of an autoimmune disease like SLE, but this is not specific for NPSLE.

Identification and evaluation of Galleria mellonella peptides with antileishmanial activity.

Leishmaniasis is a neglected disease, World Health Organization (WHO) declared it as high priority worldwide. Colombia is one of the 98 countries in which the disease caused more than 17.000 cases per year. There is a need to explore novel therapies to reduce the side effects of the current treatments. For this reason, this study was aimed to evaluate Galleria mellonella hemolymph for potential peptides with anti-parasitic activity. Larvae were challenged with Leishmania (V) panamensis promastigotes and hemolymph was analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), reversed-phase chromatography (RP-HPLC), two-dimensional gel electrophoresis and liquid chromatography-mass spectroscopy (LC/MS). The immunological response of Galleria mellonella was followed by SDS-PAGE, immunized hemolymph was fractionated by RP-HPLC where fractions 5 and 11 showed the highest antileishmanial activity. From these fractions 15 spots were isolated by 2D gel electrophoresis and evaluated by LC/MS to identify the peptides present in the spots. After the analysis Moricin-B, Moricin-C4, Cecropin-D and Anionic Peptide 2 were identified due to the immune challenge with Leishmania promastigotes. Anionic peptide 2 and Cecropin-D were synthesized and evaluated for antileishmanial activity. The results showed that Anionic peptide 2 presented more anti-parasitic activity. This study showed for the first time the anti-parasitic potential of peptides derived from hemolymph of Galleria mellonella.

Angioedema hereditario en Medellín, Colombia: evaluación clínica y de la calidad de vida / Hereditary angioedema in Medellín (Colombia): Clinical evaluation and quality of life appraisal

Introducción. El angioedema hereditario es una inmunodeficiencia primaria de carácter autosómico dominante, debida a un déficit en la proteína inhibidora del factor C1 y caracterizada por episodios recurrentes de edema subcutáneo y de las mucosas. Las impredecibles y frecuentes crisis de angioedema afectan la calidad de vida de los individuos que las padecen. Objetivo. Analizar las características clínicas de una familia con un caso índice de angioedema hereditario y determinar el impacto de la enfermedad en la calidad de vida. Materiales y métodos. En el estudio se incluyeron 26 miembros de la familia, a 25 de los cuales se les midieron los niveles sanguíneos del factor C4 del complemento y del inhibidor de C1 antigénico y funcional. Se utilizaron dos instrumentos, el SF-36 para evaluar la salud del adulto y el KIDSCREEN-27 para la calidad de vida de niños y adolescentes. Resultados. El 83 % de los individuos que reportaron síntomas cumplían con los criterios serológicos del angioedema hereditario de tipo I: valores bajos del factor C4 del complemento y del inhibidor de C1 cuantitativo (antigénico) y cualitativo (funcional). Se encontró que la calidad de vida en cuanto al bienestar psicológico y el desempeño emocional de los pacientes, se veía considerablemente afectada por los síntomas de la enfermedad. Conclusión. Este estudio provee información sobre la primera familia caracterizada con angioedema hereditario de tipo 1 en el Valle de Aburrá, Colombia. Aunque para ello se usó un instrumento genérico, se confirmó, además, el efecto negativo de la enfermedad en la calidad de vida de los individuos que la padecen.

Introduction: Hereditary angioedema is an autosomal dominant primary immunodeficiency caused by a deficiency of the C1 inhibitor protein and characterized by recurrent episodes of subcutaneous and mucosal edema. Unpredictable and frequent crisis of angioedema affect the quality of life of individuals suffering this kind of disorder. Objective: To analyze the clinical characteristics of a family with an index case of hereditary angioedema and to determine the impact of this disease on their quality of life. Materials and methods: Twenty six members of the family were included in the trial; 25 of them were analyzed for C4 complement and antigenic and functional C1 inhibitor blood levels. Two instruments (SF-365 and KIDSCREEN-27) were used to evaluate adult health quality and children and teenagers quality of life, respectively. Results: Eighty three percent (83%) of individuals reporting symptoms of the condition exhibited serological criteria of hereditary angioedema type I: low levels of both C4 complement and quantitative (antigenic) and qualitative (functional) C1 inhibitor. In relation to patients' psychological and emotional performance, their quality of life was significantly affected by the symptoms of hereditary angioedema. Conclusion: This study provides evidence of the first family in Valle de Aburrá (Colombia) characterized as having hereditary angioedema type I. Despite the use of a generic instrument, the negative impact on the quality of life of individuals suffering this disease was also confirmed.

[Hereditary angioedema in Medellín (Colombia): Clinical evaluation and quality of life appraisal]. / Angioedema hereditario en Medellín, Colombia: evaluación clínica y de la calidad de vida.

INTRODUCTION: Hereditary angioedema is an autosomal dominant primary immunodeficiency caused by a deficiency of the C1 inhibitor protein and characterized by recurrent episodes of subcutaneous and mucosal edema. Unpredictable and frequent crisis of angioedema affect the quality of life of individuals suffering this kind of disorder. OBJECTIVE: To analyze the clinical characteristics of a family with an index case of hereditary angioedema and to determine the impact of this disease on their quality of life. MATERIALS AND METHODS: Twenty six members of the family were included in the trial; 25 of them were analyzed for C4 complement and antigenic and functional C1 inhibitor blood levels. Two instruments (SF-365 and KIDSCREEN-27) were used to evaluate adult health quality and children and teenagers quality of life, respectively. RESULTS: Eighty three percent (83%) of individuals reporting symptoms of the condition exhibited serological criteria of hereditary angioedema type I: low levels of both C4 complement and quantitative (antigenic) and qualitative (functional) C1 inhibitor. In relation to patients' psychological and emotional performance, their quality of life was significantly affected by the symptoms of hereditary angioedema. CONCLUSION: This study provides evidence of the first family in Valle de Aburrá (Colombia) characterized as having hereditary angioedema type I. Despite the use of a generic instrument, the negative impact on the quality of life of individuals suffering this disease was also confirmed.

Biomarcadores proteicos en lupus neuropsiquiátrico / Protein Biomarkers in Neuropsychiatric Lupus

El lupus eritematoso sistémico es una enfermedad crónica, autoinmune, en la cual factores genéticos,epigenéticos, ambientales, hormonales e inmunológicos han demostrado tener un papel.El lupus eritematoso sistémico afecta prácticamente a todos los órganos con manifestacionescutáneas, musculoesqueléticas, cardiopulmonares, renales y neuropsiquiátricas, estas últimasagrupadas como lupus neuropsiquiátrico cuya prevalencia varía entre 12-95%. Las manifestacionesneuropsiquiátricas ocupan un lugar importante en la morbilidad y mortalidad de la enfermedady, por ende, se han asociado a un pobre pronóstico. Hasta la fecha el diagnóstico de lupus neuropsiquiátricose basa en las características clínicas, utilizando la nomenclatura y descripciónde caso del Colegio Americano de Reumatología-1999, sin embargo, la inespecificidad de estossíndromes clínicos hace aún difícil el diagnóstico. Esta dificultad es consecuencia de la etiopatogeniacompleja, la gran heterogeneidad de presentaciones clínicas, el curso impredecible de laenfermedad y, adicionalmente, las pruebas de laboratorio y de imaginología médica utilizadas noson contundentes para el diagnóstico. Es por ello que ha sido imperativa la búsqueda de biomarcadores,entre los que se han reportado auto-anticuerpos y otras proteínas. Sin embargo, estosreportes requieren de estudios complementarios para ser validados como prueba diagnóstica yasí poder ser utilizados en la práctica clínica. Se presenta, entonces, una revisión de tema acercade algunos de estos biomarcadores evaluados hasta el momento.

[Hepatitis C virus core protein production and purification in a baculovirus expression system for biological assays]. / Producción y purificación de la proteína core del virus de la hepatitis C en el sistema de expresión del baculovirus para ensayos biológicos.

BACKGROUND: The hepatitis C virus (HCV) commonly causes persistent infection. One of the viral mechanisms in preventing viral clearance is the ability of HCV to induce functional alterations of the immune system cells, specifically of dendritic cells. Viral proteins producing the dendritic cell functional alterations have been identified as the HCV core protein, which makes up the capsid structural unit. OBJECTIVE: One of the limitations to evaluate core protein properties is the difficulty in obtaining and purifying the complete protein--consisting of 191 amino acids. The aim of the current study was to produce and purify the recombinant core protein in a eukaryotic system, and to evaluate its effect in human dendritic cell cultures. RESULTS: The core protein p23 isoform was expressed in a baculovirus system and purified using isoelectric point separation and electroelution. The purity of the core protein was confirmed by silver stain and Western blot. These analyses showed the presence of two bands that correspond to p23 and p21 isoforms of core protein as previously reported. CONCLUSION: The expressed protein differed from naive core protein is terms of molecular weight, isoforms and subcellular localization. The procedures developed for core protein are applicable for expression of other membrane-associated proteins produced in eukaryotic systems.

Producción y purificación de la proteína Core del virus de la hepatitis C en el sistema de expresión del baculovirus para ensayos biológicos / Hepatitis C virus core protein production and purification in a baculovirus expression system for biological assays

Introducción. La infección por el virus de la hepatitis C (VHC) se caracteriza por la alta frecuencia de infección persistente. La capacidad del VHC para inducir alteraciones en la función de las células del sistema inmune, específicamente en las células dendríticas, parece ser una de las estrategias virales implicada en el establecimiento de la infección persistente. Esta estrategia parece estar mediada en gran parte por una de las proteínas estructurales codificada por el genoma del VHC, la proteína Core, unidad estructural de la cápside viral. Objetivo. Una de las limitantes para la evaluación de las propiedades de Core es la obtención y la purificación de la proteína nativa (191 aa). El objetivo de este estudio fue la producción y la purificación de la proteína Core completa en un sistema eucariote para evaluar las propiedades de la proteína en cultivos de células dendríticas humanas. Resultados. En este estudio se logró la producción de la proteína Core completa en el sistema de expresión de baculovirus y su purificación por la técnica de separación por punto isoeléctrico y electroelución. La pureza de la proteína obtenida se confirmó por Western blot y tinción con plata. Estos análisis mostraron dos bandas únicas correspondientes a las isoformas p23 y p21 de la proteína Core, previamente descritas en la literatura. Conclusiones. La proteína obtenida posee varias de las condiciones de la proteína Core nativa, como peso molecular, isoformas y localización subcelular. Los procedimientos descritos en este artículo son aplicables a proteínas asociadas a membranas producidas en sistemas de expresión eucarióticos