Cytokines are soluble
protein factors with importance in intercellular communication and, as such, play pivotal roles in the pathogenesis of B cell
malignancies. Evidence from in vitro cultures permitted us to choose example
cytokines that bind to different biochemical receptor types. Activated malignant B cells or stromal fibroblasts and macrophages prominently secrete the
chemokines CCL3 or CXCL12 and CXCL13, respectively. Apart from helper T cells, various cell types of the
B cell lymphoma microenvironment are capable of producing the
cytokines IL-4,
IL-6,
IL-10 and TNFα. Owing to its impact on the development of myeloid cells,
CSF-1 is among important soluble factors in the
B cell lymphoma microenvironment. Inhibitors of B cell receptor-associated
kinases often act via the blockade of
cytokine production, but also prevent
cytokine effects, e.g., chemotaxis. Increments in blood levels in
chronic lymphocytic leukemia patients compared to healthy donors and normalization upon treatment with
ibrutinib can be explained by producing cell types and modulation of
cytokine production observed in vitro.