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Background:Enhanced expression of aldehyde dehydrogenase 1 ALDH1 and phenotypic markers CD44CD24− in stem cells from breast tumors has been reported. This study was undertaken to monitor expression of these markers in cells from body cavity fluids of female patients suspected to have a malignancy.Methods:Cells from peritoneal and pleural fluids of 100 female patients were examined by diagnostic cytology and analyzed by laser flow cytometry for enhanced ALDH1 expression. Cells from 36 body cavity fluids with ALDH1brightfluorescence were then analyzed for the expression of CD44 and CD24 markers.Results:In samples positive for malignancy, ALDH1brightcells with both SSClowand SSChighwere seen. In 15 body cavity fluids positive for malignancy, the percentage of ALDH1brightcells ranged from 0.26 to 6.34 of the total cells. The percentage of ALDH1brightcells with CD44CD24−expression in these samples ranged from 0.02 to 3.66. ALDH1brightcells with CD44CD24−expression were also present in body cavity fluids of patients in whom diagnostic cytology could not detect any malignancy. However, the percentage of ALDH1brightand CD44CD24−cells amongst the 21 body cavity fluids with negative cytology was lower than that of samples with malignancy.Conclusions:Expression of ALDH1brightand the CD44CD24−phenotype in body cavity fluids in which diagnostic cytology could not find any malignant cells suggests that this phenotype may not be restricted to the putative breast tumor stem cells. It is possible that only subsets of cells with this phenotype are the putative breast tumor stem cells. © 2010 Clinical Cytometry Society

The ClickiT™ Assay developed and commercialized by Invitrogen is based on incorporation of a new 5bromo2′deoxyuridine analog, 5ethynyl2′deoxyuridine EdU into newly synthesized DNA and its recognition by azide dyes via a copper mediated “click” reaction. This relatively convenient and useful procedure depends on fixation of cells with paraformaldehyde and staining of the DNA with 7aminoactinomycinD 7AAD. Both of these procedures result in DNA histograms with broad coefficients of variation CVs. In this report, we have shown that after EdU incorporation, nuclei isolated by lysis can be incubated with the ClickiT™ Assay and stained with propidium iodide for generation of DNA histograms with low CVs. This modified procedure results in better DNA histograms by replacing 7AAD with propidium iodide and also saves processing time by eliminating the fixation and permeabilization steps. © 2009 International Society for Advancement of Cytometry

An enzyme in glucosyltransferase preparations from Streptococcusmutanscatalyzed the transfer of [14C]glucopyranoside from purified isomaltosaccharides, each containing [14C]glucopyranoside at its non-reducing terminus, to acceptor dextran, in the absence of sucrose. Half of the radioactivity present in the resulting [14C]dextrans was resistant to hydrolysis by amylo-1,6-glucosidase. Treatment of the [14C]dextrans with endodextranase resulted in extensive hydrolysis and produced [14C]-labeled limit oligosaccharides containing branch sites. Acetolysis of the [14C]-labeled limit oligosaccharides yielded [14C]nigerose, thus indicating the formation of branch sites on dextran in the absence of sucrose. The enzyme catalyzing this reaction has not been identified but appears to be independent of the major extracellular glucosyltransferases of S. mutans.