The Effect of Interleukin 4 on Protein Kinase Activities Associated With B Lymphocyte Plasma Membranes

[摘要] A variety of ligands bind to unique cell surface receptors and cause rapid changes in cell metabolism. In many systems this has been acheived by the functional modification of existing proteins, most notably through phosphoiylation. Phosphorylation of proteins has been observed in B lymphocytes on activation with antigen, lipolysaccharide and several lymphokines. Although many of the biological functions of the lymphokine IL-4 are well known, the signals transduced when IL-4 binds to its receptor are poorly understood. In the murine system it has been reported that IL-4 fails to induce the hydrolysis of inositol lipids, mobilisation of intracellular calcium or the activation of protein kinase C. However, the addition of IL-4 to isolated B cell membranes in the presence of gamma-[32P]-ATP leads to the phosphorylation of a 42 kDa protein. In the human system recent experiments suggest that the addition of IL-4 to resting human B cells results in the activation of a complex second messenger cascade involving the hydrolysis of inositol lipids, elevation of intracellular calcium and an increase in the level of cAMP.

[发布机构] University:University of Glasgow

[关键词] Biochemistry