First Clinical Evidence Of In Vivo Natural Killer (Nk) Cell Modulation In Chronic Lymphocytic Leukemia (Cll) Patients (Pts) Treated With Lenalidomide (L).

Introduction: Pts with Chronic Lymphocytic Leukemia (CLL) are reported to have quantitative and qualitative T and NK cell dysfunction. While NK cells act through non-specific killing, T-cells are more specific. The 2 types of T-lymphocytes, CD4+ (Th; helper) and CD8+ (Ts; cytotolytic/suppressor) are subcategorized based on cytokine secretion profile upon activation. Release of different cytokines from these immune cells modulates the host response. T1 cells (Th1, Ts1) secrete IL-2 and interferon-g which initiate the Th1 response- mainly CD4+ activation along with B and T cells, leading to proliferation and differentiation of these cells. T2 (Th2, Ts2) cells initiate the Th2 response (release of TNF-a, IL-10) resulting in direct lysis of the target cell by production of cytokines such as IL-4, IL-5 and IL-10.