Radioiodination of Anti-TLR5 Monoclonal Antibody

Sodium iodide [¹³¹I] (half-life = 8.04 days) was purchased from the China Institute of Atomic Energy (Beijing, China). Radioiodination of mouse anti-TLR5 mAb (100 μg/ml; Santa Cruz Biotechnology, Inc., Dallas, Texas, USA) and mouse isotype IgG (1 mg/ml; Biosynthesis Biotechnology Co., Ltd., Beijing, China) with ¹³¹I was performed according to the iodogen method, as previously described [14 (link)]. Mouse IgG served as a specific control antibody. Radioiodinated anti-TLR5 mAb and IgG were separated from free iodine using size-exclusion columns (PD-10 Sephadex G-25, GE-Healthcare, Diegem, Belgium), and the flowthrough was collected in sequential fractions. The radioactivity and concentration were measured using a gamma counter (Capintec Inc., Ramsey, NJ, USA).