Cytokine regulation of B-cell growth and differentiation

In the last few years, more than ten soluble factors (cytokines) important for regulating B cell growth and differentiation have been identified and their genes cloned. These factors are now known to influence each separate stage of normal B cell responses, namely the activation of quiescent B cells, their proliferation and differentiation into antibody secreting cells and the regulation of immunoglobulin class and subclass production. An important feature of all of these factors is their lack of target cell specificity. Each one has multiple activities both on B cells and on a range of other cell types, often in synergy with other factors. How their multiple functions are controlled in vivo is only now beginning to be understood, opening the way to the use of factors--or more probably, specific inhibitors--for the treatment of a variety of immunological diseases including allergy, autoimmunity, and possibly some forms of B cell malignancies.