| Title | Construction and Preclinical Evaluation of a 124/125I-Labeled Specific Antibody Targeting PD-L2 in Lung Cancer |
| Authors | Yao, Yuan Hou, Xingguo Liu, Song Liu, Teli Ren, Yanan Ma, Xiaokun Zhang, Qian Wang, Pei Guo, Qian Ma, Xiaopan Yang, Zhi Zhu, Hua Li, Nan |
| Affiliation | Peking Univ, Peking Univ Canc Hosp & Inst, Dept Nucl Med, Key Lab Carcinogenesis & Translat Res,Minist Educ, Beijing 100142, Peoples R China Guizhou Univ, Sch Med, Guiyang 550025, Guizhou, Peoples R China |
| Keywords | CELL EXPRESSION |
| Issue Date | Dec-2022 |
| Publisher | MOLECULAR PHARMACEUTICS |
| Abstract | Programmed cell death-ligand 2 (PD-L2) is an important emerging molecule of the immune checkpoint, which is closely related to the prognosis of patients with immune checkpoint inhibitor (ICI) therapy. The quantification of PD-L2 can provide a potential reference for patients who benefit from ICI treatment. In this study, we used iodine isotope (nat/124/125I)-labeled PD-L2 antibody (ATL2) to noninvasively detect PD-L2 expression in mice with human lung adenocarcinoma A549 cell lines. The radio-chemical yields of 125I-ATL2 and 124I-ATL2 were 73.56 +/- 3.72% and 69.46 +/- 2.05%, respectively. The radiochemical purity (RCP) of the tracers was more than 99%. The positive cell line A549-PDL2 was constructed by lentivirus. Western blot, immunofluor-escence, and flow cytometry indicated that the A549-PDL2 cells showed a higher PD-L2 protein level than the A549 cells. The dissociation constant of 125I-ATL2 binding to the PD-L2 protein was 7.25 nM. Cellular uptake experiments confirmed that the uptake of 125I-ATL2 in A549-PDL2 cells was higher than that in A549 cells at each time point (P < 0.0001). Micro-PET/CT showed significant uptake in the tumor region of A549-PDL2 tumor-bearing mice 24 h postinjection of 124I-ATL2 compared with that of other groups (SUVmax = 0.75 +/- 0.06, 0.19 +/- 0.07, and 0.27 +/- 0.05, respectively). Consistently, the biodistribution of the tracers at 24 h postinjection showed a higher tumor uptake in A549-PDL2 mice (7.11 +/- 0.38 %ID/g for 124I-ATL2 in A549-PDL2 mice vs 2.72 +/- 0.15 %ID/g for 124I-ATL2 in A549 mice vs 3.89 +/- 0.65 %ID/ g for 124I-IgG in A549-PDL2 mice). The dosimetry estimation by using Olinda software showed that the effective dose of 124I-ATL2 was 3.62 x 10-2 mSv/MBq, which is within the range of acceptable doses. Immunohistochemical results further confirmed that the expression of PD-L2 in the tumor tissues of A549-PDL2-bearing mice was higher than that of the A549 model mice. In conclusion, the development of 124/125I-ATL2 provides the first noninvasive quantification of PD-L2 expression in lung cancer by molecular imaging, which provides a new reference for screening potential beneficiaries of ICI therapy. |
| URI | http://hdl.handle.net/20.500.11897/669270 |
| ISSN | 1543-8384 |
| DOI | 10.1021/acs.molpharmaceut.2c00958 |
| Indexed | SCI(E) |
| Appears in Collections: | 北京肿瘤医院 |
