Multiparameter flow cytometric and transcriptional analyis of CD20 positive T-cells in bone marrow in patients of MGUS and de novo multiple myeloma

CD20 antigen is a transmembrane protein, previously described as a pan-B cell marker. A subgroup of T-cells was described firstly in peripheral blood and later in bone marrow in patients with hematological tumors, and certain immune-mediated diseases. During our hematological diagnostic work, we also noticed these cells in MGUS (monoclonal gammopathy of undetermined significance) and in de novo MM (multiple myeloma) cases. Previously some of these findings were considered to be an artefact, and to date, there is no consensus on the origin of CD20+ T cells. The study focuses on defining the origin and the functional properties of these cells, using flow cytometric immunophenotyping and RNA sequencing. Moreover, the study investigates the potential impact on the formation and course of the disease.