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Useful Reagents (useful + reagent)
Selected AbstractsOverexpression of CD49f in precursor B-cell acute lymphoblastic leukemia: Potential usefulness in minimal residual disease detectionCYTOMETRY, Issue 2 2009Joseph A. DiGiuseppe Abstract Background: The persistence of minimal residual disease (MRD) following therapy is an established prognostic factor in precursor B-cell acute lymphoblastic leukemia (pB-ALL). Detection of MRD in pB-ALL by flow cytometric immunophenotyping requires demonstration of abnormal antigen expression in leukemic B-cell precursors relative to that of normal B-cell precursors. The gene encoding CD49f (integrin ,-6) is one of several whose overexpression in pB-ALL at diagnosis has been associated with the subsequent detection of MRD. However, whether CD49f might be a useful reagent in the immunophenotypic detection of MRD in pB-ALL has not been evaluated. Methods: We evaluated CD49f expression by 4-color flow cytometry in normal B-cell precursors, and in a series of cases of pB-ALL, both at diagnosis and at intervals following the initiation of therapy. Results: In 10 control marrow samples, CD49f was undetectable or extremely dim in all but a minor subset of normal CD19+ B-lineage cells, whereas in 11 of 15 cases (73%) of pB-ALL, CD49f was moderate or bright at diagnosis, and persisted or became brighter after initiation of therapy. MRD detected using CD49f corresponded precisely with that obtained using a standard panel of antibodies, and permitted the detection of leukemic populations comprising as little as 0.02% of cells. Of the four pB-ALL cases in which CD49f was undetectable or dim at diagnosis, MRD was detected in two; in one of these, CD49f expression was substantially increased in the leukemic cells that persisted following initiation of therapy. Conclusions: CD49f is commonly overexpressed in p-B-ALL, and represents a potentially useful marker for the immunophenotypic detection of MRD. © 2008 Clinical Cytometry Society How to cite this article: DiGiuseppe JA, Fuller SG, Borowitz MJ. Overexpression of CD49f in precursor B-cell acute lymphoblastic leukemia: potential usefulness in minimal residual disease detection. Cytometry Part B 2008. [source] Generation of a conditional allele of the mouse prostaglandin EP4 receptorGENESIS: THE JOURNAL OF GENETICS AND DEVELOPMENT, Issue 1 2004André Schneider Abstract Genetic disruption of the mouse EP4 receptor results in perinatal lethality associated with persistent patent ductus areteriosus (PDA). To circumvent this, an EP4 allele amenable to conditional deletion using the Cre/loxP system was generated. The targeting construct was comprised of a floxed exon2 in tandem with the neomycin-resistance gene in intron 2, flanked by third 3, LoxP site. Mice homozygous for the targeted allele (EP4lox+neo/lox+neo), or following its Cre -mediated deletion (EP4del/del), also die within hours of birth with PDA. In contrast, mice homozygous for a partially recombined allele, retaining exon2 but lacking neo (EP4flox/flox), are viable and show no overt phenotype. Postnatal deletion of the floxed EP4 gene is efficiently achieved in the liver and kidney in a transgenic mouse expressing the inducible Mx1Cre recombinase. The EP mouse should provide a useful reagent with which to examine the physiologic roles of the EP4 receptor. genesis 40:7,14, 2004. © 2004 Wiley-Liss, Inc. [source] Optimized green fluorescent protein variants provide improved single cell resolution of transgene expression in ascidian embryosDEVELOPMENTAL DYNAMICS, Issue 2 2006Robert W. Zeller Abstract The green fluorescent protein (GFP) is used extensively to monitor gene expression and protein localization in living cells, particularly in developing embryos from a variety of species. Several GFP mutations have been characterized that improve protein expression and alter the emission spectra to produce proteins that emit green, blue, cyan, and yellow wavelengths. DsRed and its variants encode proteins that emit in the orange to red wavelengths. Many of these commercially available fluorescent proteins have been "codon optimized" for maximal levels of expression in mammalian cells. We have generated several fluorescent protein color variants that have been codon optimized for maximal expression in the ascidian Ciona intestinalis. By analyzing quantitative time-lapse recordings of transgenic embryos, we demonstrate that, in general, our Ciona optimized variants are detected and expressed at higher levels than commercially available fluorescent proteins. We show that three of these proteins, expressed simultaneously in different spatial domains within the same transgenic embryo are easily detectable using optimized fluorescent filter sets for epifluorescent microscopy. Coupled with recently developed quantitative imaging techniques, our GFP variants should provide useful reagents for monitoring the simultaneous expression of multiple genes in transgenic ascidian embryos. Developmental Dynamics 235:456,467, 2006. © 2005 Wiley-Liss, Inc. [source] Isolation and characterization of human anti-acetylcholine receptor monoclonal antibodies from transgenic mice expressing human immunoglobulin lociEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 6 2005Evdokia Protopapadakis Abstract The isolation of human antibodies against muscle acetylcholine receptor (AChR), the autoantigen involved in myasthenia gravis (MG), is important for the development of therapeutically useful reagents. Monovalent antibody fragments from monoclonal antibodies against the main immunogenic region (MIR) of AChR protect the receptor from the destructive activity of MG autoantibodies. Human anti-AChR ,-subunit antibody fragments with therapeutic potential have been isolated using phage display antibody libraries. An alternative approach for obtaining human mAb has been provided by the development of humanized mice. In this report, we show that immunization of transgenic mouse strains with the extracellular domain of the human AChR ,-subunit results in antibody responses and isolation of hybridomas producing human mAb. Four specific IgM mAb were isolated and analyzed. mAb170 recognized the native receptor the best and was capable of inducing AChR antigenic modulation, suggesting its specificity for a pathogenic epitope. Moreover, the recombinant antigen-binding (Fab) fragment of this mAb competed with an anti-MIR mAb, revealing that its antigenic determinant lies in or near the MIR. Finally, Fab170 was able to compete with MG autoantibodies and protect the AChR against antigenic modulation induced by MG sera. This approach will be useful for isolating additional mAb with therapeutic potential against the other AChR subunits. [source] The synthesis of dopaminergic radioligands labelled with tritium and iodine-125JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 8 2007Crist N. Filer Abstract The preparation of dopaminergic ligands radiolabelled with either tritium or iodine-125 has been an extremely important undertaking to advance understanding of this critical receptor class and the topic is reviewed from 1976 through 2006. Although not an exhaustive compilation of references, the cited examples highlight the many methods employed to prepare these useful reagents. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||