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An electrophoretic technique for transferring proteins to a nitrocellulose membrane has been applied to proteins separated in polyacrylamide gels by isoelectric focusing, and gradient, SDS and 2-dimensional electrophoresis. Allergenic proteins were then identified by successive incubation of the transfer membrane with serum from allergic individuals and with 125I-labelled anti-human IgE, followed by autoradiography. Alternatively, IgG binding proteins were detected using 125I-labelled protein A. The application of these methods was illustrated with cereal grain proteins and sera from individuals with bakers' asthma and coeliac disease. This approach allowed the easy comparison of allergens important for different patients in a single source, and of allergens present in different but cross-reacting sources.

Detection of minimal residual disease (MRD) is the most sensitive method to evaluate treatment response and one of the strongest predictors of outcome in childhood acute lymphoblastic leukemia (ALL). The 10-year update on the I-BFM-SG MRD study 91 demonstrates stable results (event-free survival), that is, standard risk group (MRD-SR) 93%, intermediate risk group (MRD-IR) 74%, and high risk group (MRD-HR) 16%. In multicenter trial AIEOP-BFM ALL 2000, patients were stratified by MRD detection using quantitative PCR after induction (TP1) and consolidation treatment (TP2). From 1 July 2000 to 31 October 2004, PCR target identification was performed in 3341 patients: 2365 (71%) patients had two or more sensitive targets (10−4), 671 (20%) patients revealed only one sensitive target, 217 (6%) patients had targets with lower sensitivity, and 88 (3%) patients had no targets. MRD-based risk group assignment was feasible in 2594 (78%) patients: 40% were classified as MRD-SR (two sensitive targets, MRD negativity at both time points), 8% as MRD-HR (MRD 10−3 at TP2), and 52% as MRD-IR. The remaining 823 patients were stratified according to clinical risk features: HR (n=108) and IR (n=715). In conclusion, MRD-PCR-based stratification using stringent criteria is feasible in almost 80% of patients in an international multicenter trial.Leukemia (2008) 22, 771–782; doi:10.1038/leu.2008.5; published online 31 January 2008 [ABSTRACT FROM AUTHOR]

Minimal residual disease (MRD) diagnostics is used for treatment stratification in childhood acute lymphoblastic leukemia. We aimed to identify and solve potential problems in multicenter MRD studies to achieve and maintain consistent results between the AIEOP/BFM ALL-2000 MRD laboratories. As the dot-blot hybridization method was replaced by the real-time quantitative polymerase chain reaction (RQ-PCR) method during the treatment protocol, special attention was given to the comparison of MRD data obtained by both methods and to the reproducibility of RQ-PCR data. Evaluation of all key steps in molecular MRD diagnostics identified several pitfalls that resulted in discordant MRD results. In particular, guidelines for RQ-PCR data interpretation appeared to be crucial for obtaining concordant MRD results. The experimental variation of the RQ-PCR was generally less than three-fold, but logically became larger at low MRD levels below the reproducible sensitivity of the assay (<10−4). Finally, MRD data obtained by dot-blot hybridization were comparable to those obtained by RQ-PCR analysis (r2=0.74). In conclusion, MRD diagnostics using RQ-PCR analysis of immunoglobulin/T-cell receptor gene rearrangements is feasible in multicenter studies but requires standardization; particularly strict guidelines for interpretation of RQ-PCR data are required. We further recommend regular quality control for laboratories performing MRD diagnostics in international treatment protocols.Leukemia (2007) 21, 706–713. doi:10.1038/sj.leu.2404535; published online 8 February 2007 [ABSTRACT FROM AUTHOR]

Most modern treatment protocols for acute lymphoblastic leukaemia (ALL) include the analysis of minimal residual disease (MRD). To ensure comparable MRD results between different MRD-polymerase chain reaction (PCR) laboratories, standardization and quality control are essential. The European Study Group on MRD detection in ALL (ESG-MRD-ALL), consisting of 30 MRD-PCR laboratories worldwide, has developed guidelines for the interpretation of real-time quantitative PCR-based MRD data. The application of these guidelines ensures identical interpretation of MRD data between different laboratories of the same MRD-based clinical protocol. Furthermore, the ESG-MRD-ALL guidelines will facilitate the comparison of MRD data obtained in different treatment protocols, including those with new drugs.Leukemia (2007) 21, 604–611. doi:10.1038/sj.leu.2404586; published online 8 February 2007 [ABSTRACT FROM AUTHOR]

Autoantibodies were looked for by immunofiuorescence (IFL) in seventy-seven cases of infectious mononucleosis (IM) at the onset of symptoms and on recovery, to determine the time of appearance, duration and range of these responses, and to correlate them with serum immunoglobulin and EB virus antibody titres. Antibodies to lymphocyte membrane demonstrated by IFL, now identified with lymphocytotoxins, were present in 46% of patients in the acute stage, persisting for less than 7 weeks. Antibodies to smooth muscle (SMA) or to contractile fibres in other tissue cells including human thyroid and rat hepatocytes, were present in over 70% of cases, some being entirely of IgM class. The highest titres occurred soon after onset and these antibodies also disappeared during convalescence. By contrast ANA, mitochondrial, microsomal and reticulin antibodies, also thyroid and gastric organ-specific reactivity were seen only occasionally owing to the young age group of the patients. In individual cases there was no correlation between the appearance of lymphocyte antibodies and SMA, or between these and the EB virus antibody titres. [ABSTRACT FROM AUTHOR]

Membrane immunoglobulins are associated with a transmembrane disulphide-linked heterodimer composed of an α-chain (mb-1) and a β-chain (B-29). The relative surface expression of all of the polypeptide chains comprising the Ig-αβ complex has been investigated using surface labeling coprecipitation analysis and two-color flow cytometric analysis. The main conclusions are that mb-1 and B-29 are B-cell surface markers on immature and mature B cells, and that all components of the surface Ig-αβ complex are expressed in stoichiometrically equivalent amounts. Thus the complex was quantitatively precipitated from digitonin lysates of 125I-surface-labeled cells with anti-B-29, anti-mb-1 or anti-Ig. Secondly, by two-color FACS analysis there was a proportionality between the relative amounts of cell surface mb-1 or B-29 and surface IgM or IgD, but not other B-cell markers (class II, 8220, FcRγ, FcR∊). Finally there was an insignificant number of B cells expressing membrane Ig without α- and β-chains, and vice versa. Thus there appears to be a closely controlled relative synthesis and surface expression of all components of the B-cell receptor complex. [ABSTRACT FROM AUTHOR]

A letter to the editor in response to the article "Improving minimal residual disease detection in precursor B-ALL based on immunoglobulin-k and heavy-chain gene rearrangements" published online on May 22, 2008 is presented.