Related Experiment Video
Updated: Jul 3, 2026

Identification of Functional Protein Regions Through Chimeric Protein Construction
Published on: January 8, 2019
A novel functional motif of osteopontin for human lymphocyte migration and survival
Zhiguo Cao1, Jianxin Dai, Kexin Fan
1School of Medicine and School of Pharmacy, Jiao Tong University, Shanghai 200025, China.
Abstract:
Osteopontin (OPN) is an extracellular matrix protein of pleiotropic properties and plays an important role in regulating lymphocyte adhesion and cytokine production associated with inflammatory processes and autoimmune diseases. Here we developed and characterized a monoclonal antibody (mAbs) (23C3D3) specific for human OPN. This antibody could inhibit OPN-induced lymphocyte adhesion, migration and survival. Epitope mapping showed that 23C3D3 could specifically recognize the phage displayed peptide (43)WLNPDP(48). In addition, a synthesized mimetic peptide (mimotope) 23P ((40)VATWLNPDPSQK(51)) could block the binding of 23C3D3 to hOPN and significantly inhibit the hOPN-induced lymphocyte adhesion, migration and survival. Moreover, mutations on the WLNPDP motif of hOPN also markedly diminished its activity for lymphocyte activation. Interestingly, this novel epitope is located in the extremely retained domain in all species. The functioning assay indicates that this novel epitope is critically involved in the lymphocyte migration and survival through activating ERK and the transcription factor NF-kappaB pathway, which can be inhibited by the motif (43)WLNPDP(48) blocking antibody, 23C3D3. These results suggest that this novel epitope of OPN may provide a potential therapeutic target for the treatment of T cell-mediated immune diseases.
Related Concept Videos
Cell Adhesion Molecules - Types and Functions
CAM Families
The Integrin family of proteins is primarily involved in a...
Cell Adhesion Molecules - Types and Functions
CAM Families
The Integrin family of proteins is primarily involved in a...
Immunoglobulin-like Cell Adhesion Molecules
Ig-CAMs exhibit either homophilic binding (to other Ig-CAMs) or heterophilic binding (to other ligands such as integrins). While most Ig-CAMs...
Cancer Cell Migration through Invadopodia
Lymphoid Cells and Tissues
Lymphoid cells consist of various types of immune system cells. These include B and T lymphocytes, which are responsible for producing antibodies and killing infected cells, respectively. Dendritic cells act as messengers between the innate and adaptive...
Structural Protein Function
Collagen, the most abundant protein in mammals, is found throughout the body. In connective tissue, such as skin, ligaments, and tendons, it provides tensile strength and elasticity. In bones and teeth, it mineralizes to form...