Cytokines involved in B-cell differentiation and their sites of action.
B cells originate from pluripotent hematopoietic stem cells and differentiate in the bone marrow into mature B cells. The differentiation of a stem cell into a mature B cell can be subdivided into five steps: early pro-B cells, late pro-B cell stage, pre-B cell stage, immature B cells, and mature B cells. Each differentiation step appears to be regulated by co-receptor and cytokines. The earliest B-cell progenitors are bound to the stromal cell surface by adhesive interactions through cell surface molecules to promote the binding of c-kit to stem cell factor (SCF). At the late pro-B cell stage, interleukin-7 (IL-7) induces proliferation and differentiation of pro-B cells to pre-B cells. Surface Ig-expressing mature B cells leave bone marrow and circulate into peripheral lymphoid organs in which they can be activated to proliferate and to differentiate into antibody-secreting cells by encountering antigens and "helper" T (TH) cells. TH cells activate B cells by their products, cytokines such as IL-4, IL-5, and IL-6, and membrane-bound stimulatory molecules including CD40 ligand. Each cytokine has pleiotropic activity on B cells and other cell types, and acts through a specific receptor. Abnormal expression of a cytokine receptor and aberrant signal transduction causes functional abnormality of B cells.
Takatsu
K
K
Department of Immunology, University of Tokyo, Japan.
D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D000818:Animals; D015703:Antigens, CD / Q000502:physiology; D000943:Antigens, Differentiation / Q000502:physiology; D001402:B-Lymphocytes / Q000166:cytology*; D002454:Cell Differentiation; D002455:Cell Division; D016207:Cytokines / Q000502:physiology*; D006801:Humans; D015847:Interleukin-4 / Q000502:physiology; D015848:Interleukin-5 / Q000502:physiology; D015850:Interleukin-6 / Q000502:physiology; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins; D009699:N-Glycosyl Hydrolases / Q000502:physiology; D011947:Receptors, Antigen, B-Cell / Q000502:physiology; D018123:Receptors, Interleukin / Q000502:physiology; D019947:Receptors, Interleukin-6; D015398:Signal Transduction; D006377:T-Lymphocytes, Helper-Inducer / Q000502:physiology
D015703:Antigens, CD; D000943:Antigens, Differentiation; D016207:Cytokines; D015848:Interleukin-5; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D011947:Receptors, Antigen, B-Cell; D018123:Receptors, Interleukin; D019947:Receptors, Interleukin-6; D015847:Interleukin-4; D009699:N-Glycosyl Hydrolases; D036541:ADP-ribosyl Cyclase; C498154:CD38 protein, human; D051997:ADP-ribosyl Cyclase 1