Comparative preclinical study of three bone marrow purging methods using PCR evaluation of residual t(14;18) lymphoma cells.
The t(14;18) chromosomal translocation occurring in most follicular lymphomas can be exploited by a Bcl2/JH polymerase chain reaction (PCR) to detect residual disease and to monitor the effectiveness of ex-vivo tumor cell immunological purging. We first demonstrated the 10(-5) Bcl2/JH PCR sensitivity with serial dilutions of OCY-LY8 lymphoma cell lines in normal mononuclear cells; and then the specificity and reproductibility of this technique by analysing follicular and non follicular lymphoma samples. With the Bcl2/JH PCR, we tested the efficiency of three marrow purging protocols with an experimentally contaminated bone marrow either treated by three anti-B cell monoclonal antibodies (mAb) followed by three rounds of rabbit complement or two rounds of immunomagnetics beads. Samples obtained after each purging were amplified by Bcl2/JH PCR and hybridized with PFL3 probe. We were able to produce a 2 to 3 log tumor cell reduction after three rounds of complement and a 4 to 5 log reduction after two rounds of beads. This study showed that it is feasible to use the Bcl2/JH PCR technique for residual cell lymphoma detection in patients undergoing intensive chemotherapy or BM transplantation. These results indicate that ex-vivo immunomagnetic BM purging is probably superior to complement mediated lysis for the eradication of B lymphoma cells from the marrow of patients undergoing autologous transplantation.
Yerly-Motta
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V
Etablissement de Transfusion Sanguine de Franche-Comté, Besançon, France.
Racadot
E
E
Fest
T
T
Bastard
C
C
Ferrand
C
C
Deschaseaux
M L
ML
Herve
P
P
D000818:Animals; D016465:Bone Marrow Purging / Q000379:methods*; D002883:Chromosomes, Human, Pair 14; D002887:Chromosomes, Human, Pair 18; D005434:Flow Cytometry; D006801:Humans; D018189:Immunomagnetic Separation; D008224:Lymphoma, Follicular / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D018365:Neoplasm, Residual; D016133:Polymerase Chain Reaction / Q000379:methods*; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014178:Translocation, Genetic