Implementation of the standard strategy for identification of Ig/TCR targets for minimal residual disease diagnostics in B-cell precursor ALL pediatric patients: Polish experience.
BACKGROUND
Minimal residual disease (MRD), detected based on immunoglobulin and T-cell receptor (Ig/TCR) gene rearrangements as markers of residual leukemic cells, is currently the most reliable prognostic factor in acute lymphoblastic leukemia (ALL). A feasibility study is presented of the standard strategy for the identification of Ig/TCR targets for MRD diagnostics in Polish ALL patients by identifying Ig/TCR gene rearrangement pattern using standard primer sets and protocols.


METHODS
The PCR-heteroduplex approach based on BIOMED-1 and BIOMED-2 protocols (recommended as the European standard) was used to detect IGH, IGK-Kde, TCRD, TCRG, and TCRB rearrangements in 58 Polish B-cell precursor ALL patients. Sequencing and homology analysis between the obtained and germline Ig/TCR sequences enabled identification of the rearrangements. The U-Gauss test was used for statistical analysis of the Ig/TCR rearrangement pattern in Polish patients compared with relevant data on other nationalities.


RESULTS
The following pattern was identified: IGH: 83% (VH-JH: 74%, DH-JH: 9%), IGK-Kde: 41%, TCRD: 78% (incomplete TCRD: 55%, Vdelta2-Ddelta3: 45%, Ddelta2-Ddelta3: 21%, Vdelta2-Jalpha: 35%), TCRG: 50%, and TCRB: 13%. Considerable convergence of the Ig/TCR pattern in Polish patients and those of other nationalities (mainly West Europeans) was demonstrated. Statistically relevant differences were only found between the incidence of DH-JH in Polish (9%) and Dutch patients (24%; p<0.05) and Polish and Italian patients (19%; p<0.05), VH-JH in Polish (74%) and Chilean patients (100%; p<0.05), and TCRG in Polish (50%) and Brazilian patients (69%; p<0.05).


CONCLUSIONS
The convergence of Ig/TCR patterns in Polish and European patients indicates that the strategy for Ig/TCR target identification based on standard primers and protocols might be directly used for the construction of Polish standards and recommendations for MRD diagnostics.
Dawidowska
Małgorzata
M
Department of Molecular and Clinical Genetics, Institute of Human Genetics, Polish Academy of Sciences, Strzeszyńska 32, 60-479 Poznań, Poland. ma.dawidowska@wp.pl
Jółkowska
Justyna
J
Szczepański
Tomasz
T
Derwich
Katarzyna
K
Wachowiak
Jacek
J
Witt
Michał
M
D000293:Adolescent; D001402:B-Lymphocytes / Q000378:metabolism*; D045744:Cell Line, Tumor; D002648:Child; D002675:Child, Preschool; D005060:Europe; D005260:Female; D015321:Gene Rearrangement; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007223:Infant; D008297:Male; D008495:Medical Oncology / Q000592:standards*; D018365:Neoplasm, Residual / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D011044:Poland; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000235:genetics / Q000276:immunology; D011379:Prognosis; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism
D007143:Immunoglobulin Heavy Chains; D011948:Receptors, Antigen, T-Cell