Through Ig/TCR rearrangement analysis of MLL-AF4+ infant ALL at diagnosis and xenograft leukemias from mice transplanted with the same diagnostic samples, we established that MLL-AF4+ infant ALL is composed of a branching subclonal architecture already at diagnosis, frequently driven by an Ig/TCR-rearranged founder clone.
The aim of this study was to identify immunobiological subgroups in 133 infant acute lymphoblastic leukemia (ALL) cases as assessed by their immunophenotype, immunoglobulin (Ig) and T-cell receptor (TCR) gene rearrangement pattern, and the presence of mixed lineage leukemia (MLL) rearrangements.