青岛大学基础医学院医学免疫学课件 chapter111213141516171819203456789111210Lymphocytes have unique,clonally distributed antigen receptors101010101010101010101010101010101010AntibodiesB cells1、CD19/CD21/CD81/CD225 and ：The co-receptor on the surface of B cell is composed of CD19、CD21 and CD81/CD225（Leu-13）with non-covalent bond.ligand：C3dg,C3d,iC3bfunction：enhance the sensitivity of B cell to antigen stimulusBTCD27CD70CD70CD27
