TY - JOUR
T1 - Development of therapeutic monoclonal antibodies against DKK1 peptide-HLA-A2 complex to treat human cancers
AU - Qian, Jianfei
AU - Wang, Qiang
AU - Xiao, Liuling
AU - Xiong, Wei
AU - Xian, Miao
AU - Su, Pan
AU - Yang, Maojie
AU - Zhang, Chuanchao
AU - Li, Yabo
AU - Zhong, Ling
AU - Ganguly, Siddhartha
AU - Zu, Youli
AU - Yi, Qing
N1 - Publisher Copyright:
© 2024 BioMed Central Ltd.. All rights reserved.
PY - 2024/1/24
Y1 - 2024/1/24
N2 - Background Targeted immunotherapy with monoclonal antibodies (mAbs) is an effective and safe method for the treatment of malignancies. Development of mAbs with improved cytotoxicity, targeting new and known tumor-associated antigens, therefore continues to be an active research area. We reported that Dickkopf-1 (DKK1) is a good target for immunotherapy of human cancers based on its wide expression in different cancers but not in normal tissues. As DKK1 is a secreted protein, mAbs binding directly to DKK1 have limited effects on cancer cells in vivo. Methods The specificity and antibody-binding capacity of DKK1-A2 mAbs were determined using indirect ELISA, confocal imaging, QIFIKIT antibody-binding capacity and cell surface binding assays. The affinity of mAbs was determined using a surface plasmon resonance biosensor. A flow cytometry-based cell death was performed to detect tumor cell apoptosis. Antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) assays were used to evaluate the ability of DKK1-A2 mAbs to mediate ADCC and CDC activities against tumor cells in vitro. Flow cytometry data were collected with an FACSymphony A3 cell analyzer and analyzed with FlowJo V.10.1 software. Human cancer xenograft mouse models were used to determine the in vivo therapeutic efficacy and the potential safety and toxicity of DKK1-A2 mAbs. In situ TUNEL assay was performed to detect apoptosis in tumors and mouse organs. Results We generated novel DKK1-A2 mAbs that recognize the DKK1 P20 peptide presented by human HLA-A∗0201 (HLA-A2) molecules (DKK1-A2 complexes) that are naturally expressed by HLA-A2 + DKK1 + cancer cells. These mAbs directly induced apoptosis in HLA-A2 + DKK1 + hematologic and solid cancer cells by activating the caspase-9 cascade, effectively lysed the cancer cells in vitro by mediating CDC and ADCC and were therapeutic against established cancers in their xenograft mouse models. As DKK1 is not detected in most human tissues, DKK1-A2 mAbs neither bound to or killed HLA-A2 + blood cells in vitro nor caused tissue damage in tumor-free or tumor-bearing HLA-A2-transgenic mice. Conclusion Our study suggests that DKK1-A2 mAbs may be a promising therapeutic agent to treat human cancers.
AB - Background Targeted immunotherapy with monoclonal antibodies (mAbs) is an effective and safe method for the treatment of malignancies. Development of mAbs with improved cytotoxicity, targeting new and known tumor-associated antigens, therefore continues to be an active research area. We reported that Dickkopf-1 (DKK1) is a good target for immunotherapy of human cancers based on its wide expression in different cancers but not in normal tissues. As DKK1 is a secreted protein, mAbs binding directly to DKK1 have limited effects on cancer cells in vivo. Methods The specificity and antibody-binding capacity of DKK1-A2 mAbs were determined using indirect ELISA, confocal imaging, QIFIKIT antibody-binding capacity and cell surface binding assays. The affinity of mAbs was determined using a surface plasmon resonance biosensor. A flow cytometry-based cell death was performed to detect tumor cell apoptosis. Antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) assays were used to evaluate the ability of DKK1-A2 mAbs to mediate ADCC and CDC activities against tumor cells in vitro. Flow cytometry data were collected with an FACSymphony A3 cell analyzer and analyzed with FlowJo V.10.1 software. Human cancer xenograft mouse models were used to determine the in vivo therapeutic efficacy and the potential safety and toxicity of DKK1-A2 mAbs. In situ TUNEL assay was performed to detect apoptosis in tumors and mouse organs. Results We generated novel DKK1-A2 mAbs that recognize the DKK1 P20 peptide presented by human HLA-A∗0201 (HLA-A2) molecules (DKK1-A2 complexes) that are naturally expressed by HLA-A2 + DKK1 + cancer cells. These mAbs directly induced apoptosis in HLA-A2 + DKK1 + hematologic and solid cancer cells by activating the caspase-9 cascade, effectively lysed the cancer cells in vitro by mediating CDC and ADCC and were therapeutic against established cancers in their xenograft mouse models. As DKK1 is not detected in most human tissues, DKK1-A2 mAbs neither bound to or killed HLA-A2 + blood cells in vitro nor caused tissue damage in tumor-free or tumor-bearing HLA-A2-transgenic mice. Conclusion Our study suggests that DKK1-A2 mAbs may be a promising therapeutic agent to treat human cancers.
KW - Antibodies, Neoplasm
KW - Hematologic Neoplasms
KW - Immunotherapy
KW - Translational Medical Research
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UR - http://www.scopus.com/inward/citedby.url?scp=85183333735&partnerID=8YFLogxK
U2 - 10.1136/jitc-2023-008145
DO - 10.1136/jitc-2023-008145
M3 - Article
C2 - 38267222
AN - SCOPUS:85183333735
SN - 2051-1426
VL - 12
JO - Journal for immunotherapy of cancer
JF - Journal for immunotherapy of cancer
IS - 1
M1 - e008145
ER -