RESUMEN
Detection of minimal residual disease (MRD) in chronic lymphocytic leukaemia (CLL) is becoming increasingly important as treatments improve. An internationally harmonised four-colour (CLR) flow cytometry MRD assay is widely used but has limitations. The aim of this study was to improve MRD analysis by identifying situations where a less time-consuming CD19/CD5/κ/λ analysis would be sufficient for detecting residual CLL, and develop a six-CLR antibody panel that is more efficient for cases requiring full MRD analysis. In 784 samples from CLL patients after treatment, it was possible to determine CD19/CD5/κ/λ thresholds that identified cases with detectable MRD with 100% positive predictive value (PPV). However, CD19/CD5/κ/λ analysis was unsuitable for predicting iwCLL/NCI response status or identifying cases with no detectable MRD. For the latter cases requiring a full MRD assessment, a six-CLR assay was designed comprising CD19/CD5/CD20 with (1) CD3/CD38/CD79b and (2) CD81/CD22/CD43. There was good correlation between four-CLR and six-CLR panels in dilution studies and clinical samples, with 100% concordance for detection of residual disease at the 0.01% (10(-4)) level (n=59) and good linearity even at the 0.001-0.01% (10(-5)-10(-4)) level. A six-CLR panel therefore provides equivalent results to the four-CLR panel but it requires fewer reagents, fewer cells and a much simpler analysis approach.
Asunto(s)
Biomarcadores de Tumor/análisis , Citometría de Flujo/normas , Leucemia Linfocítica Crónica de Células B/patología , Neoplasia Residual/diagnóstico , Antígenos CD/análisis , Europa (Continente) , Humanos , Cadenas Ligeras de Inmunoglobulina/inmunología , Cadenas kappa de Inmunoglobulina/inmunología , Cadenas lambda de Inmunoglobulina/inmunología , Inmunofenotipificación , Leucemia Linfocítica Crónica de Células B/inmunología , Estadificación de Neoplasias , Neoplasia Residual/inmunología , Pronóstico , Sensibilidad y EspecificidadRESUMEN
RNA interference has been used to investigate the function of a cathepsin L cysteine proteinase Mi-cpl-1, in the plant-parasitic nematode Meloidogyne incognita. A reduction in gene transcript was observed and the number of nematodes infecting plants was reduced by almost 60% as was the number of established females producing eggs at 21 days post-infection. The cysteine proteinase activity of M. incognita, reported by the substrate GLUpNA, was inhibited by the cysteine proteinase inhibitor Oc-IDeltaD86. A reduction in cysteine proteinase activity was also seen following RNAi of Mi-cpl-1 in J2 stage nematodes. In situ hybridization analysis in young and mature female nematodes has shown that Mi-cpl-1 is expressed in the intestine, which suggests that its product is a digestive enzyme. The effects of knocking-out Mi-cpl-1gene function were consistent with a reduction in feeding efficiency. Here, we have shown a correlation between transcript abundance proteinase activity and parasitic success of M. incognita.