| 内容提要: |
Autoimmune disease, such as lupus erythematosus (SLE), rheumatoid arthritis(RA), B cell chronic lymphocytic leukemia(B-CLL)，multiple myeloma(MM), is a condition arising from an abnormal immune response to a normal body part. B-cell activating factor (BAFF) and a proliferation-inducing ligand (APRIL) are members of tumor necrosis factor superfamily, they can bind with the receptor in B cell to increase the proliferation and differentiation. B-cell activating factor (BAFF) and a proliferation-inducing ligand(APRIL) share 33% amino acid and 48% DNA homology with each other and have similar three-dimensional structure. BAFF and APRIL share two common TNF receptors: TACI and BCMA. The two ligands play vital roles in immune homeostasis by means of binding to their receptors. But there is a receptor that binds only BAFF rather than APRIL. So we want to find the specific antagonist by investigate BAFF-receptor(BR3). We spilt the BR3 extracellular domain to BR3-1 and BR3-2, then construct and purified Fc fusion proteins. Then we found that both BR3-1-Fc and BR3-2-Fc can bind with BAFF. The rigid domain near BR3 extracellularly conserved domain also make a function for BR3 high affinity to BAFF. |