Markers for Minimal Residual Disease (MRD) in B-Lineage Acute Lymphoblastic Leukemia (B-ALL): Analysis of IgH Gene Rearrangement Repertoire (AIRR) vs Conventional Strategy

• Published in: Blood 2007-11, Vol.110 (11), p.4243-4243
• Main Authors: Morley, Alexander, Brisco, Michael, Latham, Sue, Wilczek, Vicki, Hughes, Elisabeth, Budgen, Brad, Sutton, Rosemary, Bahar, Anita, Malek, Maria, Marshall, Glenn
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V110.11.4243.4243

Background: Detection of molecular markers for monitoring MRD in B-ALL conventionally involves searching for a variety of immunoglobulin and T-cell receptor rearrangements. However preliminary studies have suggested that AIRR may have advantages. Aim :To directly compare AIRR to the conventional approach for detection of molecular markers. Materials and Methods Marrow samples from a consecutive series of 50 children with B-linage ALL were studied by the conventional approach in Sydney and by AIRR in Adelaide. AIRR involves use of primers specific for individual V and J segments of the IgH gene followed by sequencing of amplified products and calculation of the relative abundance of rearrangements from the quantitative PCR data. IgH rearrangements are regarded as suitable for detecting the major leukemic clone if they comprise > 10% of the rearrangements present. Incomplete D-J rearrangements are detected using primers directed towards genomic regions upstream of the D segments. Results Table 1 shows the number of patients with either 0, 1 or 2 rearrangements suitable for monitoring MRD of the major leukemic clone. The 2 approaches appeared to be equivalent in terms of the number of markers for the major clone, but, of the rearrangements detected conventionally, 49% were IgH rearrangements and 51% involved IgK or various T-cell receptor genes. All of the IgH rearrangements detected in the 50 patients, grouped by abundance, are shown in Table 2. Table 1number of patientsno marker1 marker2 markersconventional approach2939AIRR21236Table 2relative abundance of rearrangement100-10%10-1%