LEESGGGLVQPGGSMK, a proteolysis peptide, is a constituent of Infliximab, a chimeric monoclonal IgG1 antibody that selectively binds to TNF-α. It can be employed for quantitative assessment of Infliximab.

The anti-TNF antibodies blocking the action of TNF alpha revolutionized therapy of TNF-related diseases such as Inflammatory Bowel Disease, lupus, ulcerative colitis, ankylosing spondylitis, psoriatic arthritis and rheumatoid arthritis. By neutralizing TNF activity, anti-TNF antibodies promote mucosal healing and induce long-term remissions in vivo. The main anti-TNF antibodies that are currently authorized encompass Infliximab, Etanercept, Adalimumab, Certolizumab and Golimumab[1].