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La prueba de autoanticuerpos es cada vez más relevante en el diagnóstico de las enfermedades autoinmunes. Como consecuencia, la detección de autoanticuerpos se reconoce cada vez más en los criterios de clasificación y las directrices de diagnóstico. Es importante conocer la presencia de los autoanticuerpos naturales y las características que permiten su diferenciación con los autoanticuerpos patológicos. Varias características especiales de los autoanticuerpos y el desarrollo de nuevas metodologías hacen que la interpretación correcta de los resultados de las pruebas de anticuerpos sea cada vez más difícil. En este artículo se revisa las características del autoanticuerpo, su reconocimiento como un analito heterogéneo y su implicancia en los métodos de detección, así como la utilidad en la práctica clínica.

Testing for autoantibodies is becoming more and more relevant, for diagnosing autoimmune disease. As a consequence, the detection of autoantibodies is increasingly recognized in classification criteria and diagnostic guidelines. It is important to know the presence of natural autoantibodies and the characteristics that allow their differentiation with pathological autoantibodies. Several special features of the autoantibodies and the development of new methodologies make the correct interpretation of the results of the antibody tests more and more difficult. In this article we review the characteristics of the autoantibody, its recognition as a heterogeneous analyte and its implication in the detection methods, as well as the utility in the clinical practice.

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BACKGROUND: Malignant transformation of cells is often accompanied by up-regulation of glycolysis-related enzymes and transporters, as well as a distortion of mitochondrial respiration. As a consequence, most malignant tumors utilize high amounts of glucose and produce and accumulate high concentrations of lactate, even in the presence of oxygen. This phenomenon has been termed 'Warburg Effect'. Here, we aimed at resolving the interrelation between tumor metabolism, reactive oxygen species, double strand DNA breaks and radio-resistance in ovarian cancer-derived cells. METHODS: As a model system two ovarian cancer-derived cell lines, OC316 and IGROV-1, and its corresponding xenografts were used. First, the metabolic properties of the xenografts were tested to ensure that initial in vitro data might later be transferred to in vivo data. In parallel, three inhibitors of tumor cell metabolism, 2-deoxy-D-glucose, an inhibitor of glycolysis, oxamate, a pyruvate analogue and inhibitor of lactate dehydrogenase, and rotenone, a specific inhibitor of mitochondrial electron complex I, were tested for their effect on the metabolism and radio-sensitivity of the respective ovarian cancer-derived cell lines. RESULTS: We found that all three inhibitors tested led to significant changes in the tumor cell energy metabolism at non-cytotoxic concentrations. Furthermore, we found that inhibition of tumor glycolysis by 2-deoxy-D-glucose in combination with rotenone decreased the radio-resistance at a clinically relevant radiation dose. This apparent radio-sensitizing effect appears to be based on an increased level of double strand DNA breaks 1 h and 24 h after gamma irradiation. Both cancer-derived cell lines maintained their metabolic properties, as well as their protein expression profiles and levels of reactive oxygen species in xenografts, thus providing a suitable model system for further in vivo investigations. CONCLUSION: A combination of metabolic inhibitors and reactive oxygen species-generating therapies, such as irradiation, may effectively enhance the therapeutic response in particularly metabolically highly active (ovarian) tumors.

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A lo largo de la medicina, los investigadores están en la persecución de los biomarcadores. Entre sus usos, pueden ayudar a dilucidar la predisposición genética a la enfermedad e identificar los factores desencadenantes, en la práctica, estos marcadores pueden permitir el diagnóstico, tratamiento y el desarrollo de estrategias para la reducción del riesgo. Los anticuerpos antinucleares (ANA) es una de las pruebas más reconocidas de la inmunología como marcador de screening de enfermedad autoinmune aunque es muy informativo actualmente se enfrenta a grandes desafíos. Uno de estos desafíos y al parecer el más importante es la presencia de estos anticuerpos en la población general y los factores asociados a ellos. El hallazgo de ANA en un individuo sano es generalmente de significación desconocida. Sin embargo, un subconjunto de estas personas está en riesgo para el desarrollo de enfermedad autoinmune. Se realizó un estudio descriptivo, transversal en 150 donantes de banco de sangre del Hospital Nacional Dos de Mayo, los anticuerpos antinucleares fueron detectados por lnmunofluorescencia indirecta utilizando las células Hep 2 como sustrato. La prevalencia de expresividad hallada fue de 10,7 por ciento (IC 95 por ciento 5,8-15,6 por ciento). La frecuencia de ANA generalmente aumentó con la edad (P=0,01) y fueron significativamente mayores en mujeres que en hombres (12,3 por ciento frente a 9 por ciento, P<0,001), los patrones más prevalentes fueron moteado fino 31.3 por ciento y moteado fino denso 25 por ciento, y los títulos más frecuentes fueron 1:80 68.8 por ciento y 1:160 12.5 por ciento. El presente estudio confirma la posibilidad de que una persona pueda ser portadora de ANAs sin que sufra de ninguna afección autoinmune. El potencial patogénico de estos anticuerpos en individuos sanos aún es desconocido. Se recomienda que los laboratorios que realicen pruebas de inmunofluorescencia ANA debe informar resultados, tanto en título y patrón. Los ANA puede ser un...

Throughout medicine, investigators are in hot pursuit of biomarkers. Among its uses, may help to elucidate the genetic predisposition to the disease and identify the triggers, in practice, these markers may allow the diagnosis, treatment and development of strategies for risk reduction. Antinuclear antibodies (ANA) is one of the most recognizable evidence of immunology as a screening marker of autoimmune disease is very informative but currently faces great challenges. One of these challenges and apparently the most important is the presence of these antibodies in the general population and the factors associated with them. The finding of ANA in a healthy individual is usually of unknown significance. However, a subset of these individuals is at risk for developing autoimmune disease. A cross sectional study was conducted in 150 healthy blood donors Hospital Dos de Mayo, antinuclear antibodies was detected by indirect immunofluorescence using Hep 2 cells as substrate. The prevalence of expressivity was of 10.7 per cent (lC 95 per cent 5.8 - 15.6 per cent). The frequency of ANA generally increased with age (P=0.01) and were significantly higher in women than men (12.3 per cent versus 9 per cent, P<0.001), the most prevalent patterns were nuclear fine speckled 31.3 per cent and dense fine speckled pattern 25 per cent, and the most frequent titles 1:80 68.8 per cent and 1:160 12.5 per cent. This study confirms the possibility that a person can be a carrier of ANAs without suffering from any autoimmune condition. The pathogenic potential of these antibodies in healthy individual s is still unknown. It is recommended that laboratories performing immunofluorescence ANA should report results both in degree and pattern. The ANA can be a useful discriminant in recognizing certain diseases, but can be confusing when there is no adequate interpretation.

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Many solid tumors show a large variability in glycolytic activity and lactate accumulation, which has been correlated with different metastatic spread, radioresistance and patient survival. To investigate potential differences in protein profiles underlying these metabolic variances, the highly glycolytic human ovarian cancer cell line OC316 was investigated and compared with the less glycolytic line IGROV-1. Extracellular acidification and oxygen consumption were analyzed with an extracellular flux analyzer. Glycolysis-associated proteins, including specific membrane transporters, were quantified through in-cell western analyses. Metabolic properties of corresponding tumor xenografts were assessed via induced metabolic bioluminescence imaging. Extracellular flux analyses revealed elevated bioenergetics of OC316 cells. Hexokinase II, pyruvate kinase, pyruvate dehydrogenase E1 beta subunit and pyruvate dehydrogenase kinase 1, as well as the glucose transporter 1 and the monocarboxylate transporter 4, were overexpressed in these cells compared with IGROV-1. When generating tumor xenografts in SCID mice, cells maintained their glycolytic behavior, i.e. OC316 showed higher lactate concentrations than IGROV-1 tumors. In summary, a congruency between protein profiles and metabolic properties has been demonstrated in the human ovarian cancer lines investigated. Also, a perpetuation of glycolytic characteristics during the transition from in vitro to the in vivo situation has been documented. This model system could be useful for systematic studies on therapeutic intervention by manipulation of tumor glycolysis and associated pathways.

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BACKGROUND AND PURPOSE: To study whether pre-therapeutic lactate or pyruvate predict for tumour response to fractionated irradiation and to identify possible coherencies between intermediates of glycolysis and expression levels of selected proteins. MATERIALS AND METHODS: Concentrations of lactate, pyruvate, glucose and ATP were quantified via bioluminescence imaging in tumour xenografts derived from 10 human head and neck squamous cell carcinoma (HNSCC) lines. Tumours were irradiated with 30 fractions within 6 weeks. Expression levels of the selected proteins in tumours were measured at the mRNA and protein level. Tumour-infiltrating leucocytes were quantified after staining for CD45. RESULTS: Lactate but not pyruvate concentrations were significantly correlated with tumour response to fractionated irradiation. Lactate concentrations in vivo did not reflect lactate production rates in vitro. Metabolite concentrations did not correlate with GLUT1, PFK-L or LDH-A at the transcriptional or protein level. CD45-positive cell infiltration was low in the majority of tumours and did not correlate with lactate concentration. CONCLUSIONS: Our data support the hypothesis that the antioxidative capacity of lactate may contribute to radioresistance in malignant tumours. Non-invasive imaging of lactate to monitor radiation response and testing inhibitors of glycolysis to improve outcome after fractionated radiotherapy warrant further investigations.

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