title: Non-invasive imaging of Toll-like receptor 5 expression using131I-labeled mAb in the mice bearing H22 tumors.
abstract: Toll-like receptor 5 (TLR5) is overexpressed in several cancers and metastases, and presents an enticing target for molecular imaging of primary tumors. In the present study,131I-anti-TLR5 monoclonal antibody (mAb) was evaluated for its use as a novel radiotracer for imaging hepatocarcinoma in mice bearing H22 tumors. The expression of TLR5 was analyzed by quantitative polymerase chain reaction and immunohistochemistry. The anti-TLR5 mAb and isotype immunoglobulin G (IgG) were radiolabeled with iodine-131 by the Iodogen method. Thein vitrostability of iodinalized probes was determined in serum or saline for a series of times, and then evaluated with radio-thin-layer chromatography. The biodistribution study and autoradiography were performed in H22 tumor-bearing mice. It was found that H22-xenografted tumor tissue exhibited a higher level of TLR5 expression compared with normal liver tissues.131I-anti-TLR5 mAb and131I-IgG were obtained subsequent to purification, with high radiochemical purity (>95%), and remained stable for 48 h in human serum. The target-to-non-target ratio in the131I-anti-TLR5 mAb group was significantly higher compared with the131I-IgG group. The biodistribution study and autoradiography demonstrated that131I-anti-TLR5 mAb was specifically retained in hepatocarcinoma with a high tumor uptake. Altogether, these results show that131I-anti-TLR5 mAb is capable of detecting lesions in a TLR5-expressing tumor, with high target selectivity, and may offer a promising agent for hepatocarcinoma diagnosis and encourage further investigation.
authors.affiliation: Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Experimental Nuclear Medicine, School of Medicine, Shandong Univeristy, Jinan, Shandong 250012, P.R. China.
authors.forename: Changya
authors.initials: C
authors.lastname: Yang
authors.affiliation: Department of Laboratory, The Second Affiliated Hospital, Shandong University of Traditional Chinese Medicine, Jinan, Shandong 250012, P.R. China.
authors.forename: Qingying
authors.initials: Q
authors.lastname: Yun
authors.affiliation: Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Experimental Nuclear Medicine, School of Medicine, Shandong Univeristy, Jinan, Shandong 250012, P.R. China.
authors.forename: Hukui
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Nuclear Medicine, Qilu Hospital, School of Medicine, Shandong University, Jinan, Shandong 250012, P.R. China.
authors.forename: Guangjie
authors.initials: G
authors.lastname: Yang
authors.affiliation: Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Experimental Nuclear Medicine, School of Medicine, Shandong Univeristy, Jinan, Shandong 250012, P.R. China.
authors.forename: Ting
authors.initials: T
authors.lastname: Liang
authors.affiliation: Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Experimental Nuclear Medicine, School of Medicine, Shandong Univeristy, Jinan, Shandong 250012, P.R. China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Experimental Nuclear Medicine, School of Medicine, Shandong Univeristy, Jinan, Shandong 250012, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Song
authors.affiliation: Department of Nuclear Medicine, Qilu Hospital, School of Medicine, Shandong University, Jinan, Shandong 250012, P.R. China.
authors.forename: Jiankui
authors.initials: J
authors.lastname: Han
authors.affiliation: Key Laboratory for Experimental Teratology of the Ministry of Education and Institute of Experimental Nuclear Medicine, School of Medicine, Shandong Univeristy, Jinan, Shandong 250012, P.R. China.
authors.forename: Guihua
authors.initials: G
authors.lastname: Hou
keywords: autoradiography; hepatocellular carcinoma; molecular imaging; radioiodine; toll-like receptor 5