Specific Associations Between Clinical Signs, Immune Cells, Disease Genetic Background and Burden in a Group of Patients with B-Cell Chronic Lymphocytic Leukemia

Traffic of tumor- and normal cells through the peripheral blood (PB) of patients with B-cell chronic lymphocytic leukemia (B-CLL) to the lymph nodes (LN) or spleen/ liver sites is governed by specific changes in surface and intracellular molecule expression. The study aims to investigate the potential association between different lymphocyte subsets, chemokine receptors or genetic alterations and specific clinical signs in a group of B-CLL patients. Forty-three patients were included in the study. The expression of CCR7, CXCR5, CXCR3, CCR4, CD3, CD4, CD8, CD27, CD28, CD45RA, CD25, CD127, CD38 was tested by multiparameter flow cytometry. Genetic alterations were determined by MLPA. We found increased frequency of CD38+ B-CLL cells directly correlated with the presence of LN>5cm. CXCR5 and CCR7 are homogenously expressed by monoclonal B-CLL cells. CCR4+ B-CLL cell frequency is found to be lower in the PB of patients presenting particular LN involvement. Heterogeneous and complex genetic alterations were found and only the presence of trisomy 12 associated with less frequent axillary LN involvement. We also report a significant increase in the frequency of total T cells and T cell subsets (effector- and central memory CD4+ T cells, regulatory T cells, follicular T helper cells, distinct functional CD8+ T cells) with the occurrence of specific clinical manifestations. Chemokine receptor expression on circulating CD4+ T cell subsets was augmented in connection to some specific LN locations. Consequently, clinical manifestations in B-CLL are linked to both, factors intrinsic to the monoclonal B cells, and external influences coming from the microenvironment.