Purification of trisomy 12 subclone in chronic lymphocytic leukaemia using imaging flow cytometry and fluorescence in situ hybridisation in suspension (FISH-IS): Poster ID: 340

Introduction: Trisomy of chromosome 12 is reported as one of the most common chromosomal aberrations in Chronic Lymphocytic Leukaemia (CLL), and confers an intermediate prognosis with a median overall survival of 114 months [1]. CLL cases with trisomy 12 are unique in their increased expression of integrins (such as CD49d and CD38) compared to other cytogenetic categories [2–4]. Trisomy 12 is also associated with mutations of NOTCH1 and a germline, unmutated configuration of the immunoglobulin heavy chain gene in NOTCH1 mutant cases [5,6].

These associations have however been inferred from analysis of whole populations of peripheral blood mononuclear cells (PBMCs) or CD19 positive B-lymphocytes. It is well established that a single patient’s CLL sample consists of a heterogeneous cell population, with multiple subclones present even at diagnosis, and that the subclonal composition and its evolution over time has a clinical impact [7–9]. We propose to use a novel methodology, combining fluorescence in situ hybridisation with flow cytometric sorting, to enable isolation and comprehensive analysis of the trisomic 12 CLL subclone.