B and T Lymphocyte Antigen Receptors VB Va y E CB Co CH2 CH2 Iga/IgB CH3 CH3 Iga/IgB fyn Blk,Fyn or Lyn φ派 2 light chains(orK) 2 Chains a/B(95%)ory/(5%) 2 heavy chains(5 isotypes:IgG,M,A,D,E) 2 Binding sites(Divalent) 1 Binding site(Monovalent) Secreted into circulation Membrane Bound,Not Secreted Binds Soluble Antigen Binds Antigen Complexed with MHC BDC2 light chains ( or ) 2 heavy chains (5 isotypes: IgG, M, A, D, E) 2 Binding sites (Divalent) Secreted into circulation Binds Soluble Antigen 2 Chains / (95%) or / (5%) 1 Binding site (Monovalent) Membrane Bound, Not Secreted Binds Antigen Complexed with MHC Zap 70 fyn lck  e z V V C C CH1 CH2 CH3 CH2 CH3 CH1 CL CL VL VL VH VH e  z Ig/Ig Ig/Ig Blk, Fyn or Lyn B and T Lymphocyte Antigen Receptors BDC