Proteoglycan Aggrecan Conducting T Cell Activation and Apoptosis in a Murine Model of Rheumatoid Arthritis

Figure 1

The schematic structure of PG aggrecan. The macromolecule consists of a central core protein to which hundreds of chondroitin sulphate (CS) and keratin sulfate (KS) side chains are attached. Note that the N- and C-terminal G1 and G3 domains are “overrepresented” in the figure for better visibility. The four most important T cell epitopes are indicated by black rectangles in the G1 and G3 domains. IGD: interglobular domain, SCR: complement regulatory protein-like module, and CLD: C-type lectin-like domain. Two dominant arthritogenic epitopes (5/4E8 and P135H), which are discussed in more detail in this work, are indicated.