CD40L stimulation enhances the ability of conventional metaphase cytogenetics to detect chromosome aberrations in B-cell chronic lymphocytic leukaemia cells.
Conventional metaphase cytogenetics underestimates the frequency of specific chromosome aberrations in B-cell chronic lymphocytic leukaemia (B-CLL) as a result of the very low proliferative activity of these cells in vitro. New molecular approaches, such as fluorescence in situ hybridization (FISH) or comparative genomic hybridization (CGH), may circumvent this problem, at least in part, but these techniques are either strongly dependent on the knowledge of candidate regions or detect only unbalanced aberrations. In the present study, we analysed 27 B-CLL peripheral blood samples by metaphase cytogenetics after CD40 ligand (CD40L)-induced cell cycle stimulation. In comparison with the simultaneous use of B-cell mitogens such as 12-O-tetradecanoylphorbol-13-acetate (TPA), lipopolysaccharide (LPS) and pokeweed mitogen (PWM), CD40L stimulation of B-CLL cells induced a threefold increase in metaphases amenable to analysis by conventional cytogenetics. The analysis of these metaphases confirmed all genetic abnormalities detected by FISH. Moreover, CD40L-enhanced cytogenetics revealed complex karyotypic aberrations in 11 out of 27 patients (41%). In one case, a balanced translocation t(11;16)(p15;p13.1), so far unreported in B-CLL, was detected. Taken together, the results of our study show the potential of CD40L-enhanced metaphase cytogenetics to detect more and new chromosome aberrations in B-CLL.
GSF, National Research Center for Environment and Health, Genzentrum and Medizinische Klinik III, Klinikum der Universitaet Muenchen Grosshadern, Germany. buhmann@lmb.uni-muenchen.de
Raymund
R
Buhmann
Christian
C
Kurzeder
Jutta
J
Rehklau
Doreen
D
Westhaus
Sabina
S
Bursch
Wolfgang
W
Hiddemann
Torsten
T
Haferlach
Michael
M
Hallek
Claudia
C
Schoch
D016475:3T3 Cells; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001402:B-Lymphocytes / Q000473:pathology; D023201:CD40 Ligand / Q000494:pharmacology*; D002453:Cell Cycle / Q000187:drug effects; D002869:Chromosome Aberrations; D018920:Coculture Techniques; D020732:Cytogenetic Analysis; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics* / Q000276:immunology; D008297:Male; D008677:Metaphase; D051379:Mice; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014162:Transfection
D023201:CD40 Ligand