{"doi":"10.2147/ott.s255299","title":"Identification and Targeting of Thomsen–Friedenreich and IL1RAP Antigens on Chronic Myeloid Leukemia Stem Cells Using Bi-Specific Antibodies","abstract":"INTRODUCTION: Quiescent leukemia stem cells (LSCs) play a major role in therapeutic resistance and disease progression of chronic myeloid leukemia (CML). LSCs belong to the primitive population; CD34+CD38-Lin-, which does not distinguish normal hematopoietic stem cells (HSC) from CML LSCs. Because Thomsen-Friedenreich/CD176 antigen is expressed on CD34+ HSC and IL1RAP is tightly correlated to BCR-ABL expression, we sought to increase the specificity towards LSC by using additional biomarkers. METHODS: We evaluated the co-expression of both antigens on CD34+ peripheral blood mononuclear cells (PBMCs) from both healthy volunteers and CML patients, using flow cytometry. Then, we used site-directed mutagenesis to induce knob-in-hole mutations in the human IgG heavy chain and the human lambda light chain to generate the bi-specific antibody (Bis-Ab) TF/RAP that binds both antigens simultaneously. We measured complement-directed cytotoxicity (CDC) in CML samples with the Bis-Ab by flow cytometry. RESULTS: In contrast to healthy volunteers, CML samples displayed a highly significant co-expression of CD176 and IL1RAP. When either a double-positive cell line or CML samples were treated with increasing doses of Bis-Ab, increased binding and CDC was observed indicating co-operative binding of the Bis-Ab as compared to monoclonal antibodies. DISCUSSION: These results show that the bi-specific antibody is capable of targeting IL1RAP+ and CD176+ cell population among CML PBMCs, but not corresponding normal cells in CDC assay. We hereby offer a novel strategy for the depletion of CML stem cells from the bulk population in clinical hematopoietic stem cell transplantation.","journal":"OncoTargets and Therapy","year":2021,"id":205772,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":7,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9628,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2021-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":789084,"name":"Chengxiang Wu","orcid":"0000-0002-6184-187X","position":1,"is_corresponding":false},{"id":442089,"name":"Fayez M. Saleh","orcid":"0000-0001-8417-8874","position":2,"is_corresponding":false},{"id":789587,"name":"Eman Abdel-Moemen Mohammed","orcid":null,"position":3,"is_corresponding":false},{"id":789085,"name":"Soha Younes","orcid":"0000-0003-1755-9954","position":4,"is_corresponding":false},{"id":789588,"name":"Naglaa Elsayed Hassan","orcid":null,"position":5,"is_corresponding":false},{"id":789086,"name":"Theresa C. Brown","orcid":"0000-0002-9261-3853","position":6,"is_corresponding":false},{"id":442096,"name":"Eckhard Alt","orcid":"0000-0002-6687-139X","position":7,"is_corresponding":false},{"id":442092,"name":"James E. Robinson","orcid":"0000-0002-9215-9523","position":8,"is_corresponding":false},{"id":789589,"name":"Fouad M. Badr","orcid":null,"position":9,"is_corresponding":false},{"id":442097,"name":"Stephen E. Braun","orcid":"0000-0002-4521-2678","position":10,"is_corresponding":false},{"id":789083,"name":"Raghda E. Eldesouki","orcid":"0000-0002-8860-3484","position":0,"is_corresponding":true}],"reference_count":45,"raw_metadata":null,"created_at":"2026-07-18T23:51:33.996102Z","pmid":"33519209","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}