CN-121248786-B - Anti-urokinase plasminogen activator receptor antibodies and uses thereof

Abstract

The invention belongs to the technical field of biology, and provides an anti-urokinase plasminogen activator receptor antibody or an antigen binding fragment thereof and application thereof. The antibodies or antigen binding fragments thereof of the invention comprise a heavy chain variable region comprising heavy chain complementarity determining regions HCDR1, HCDR2 and HCDR3 and a light chain variable region comprising light chain complementarity determining regions LCDR1, LCDR2 and LCDR3. The antibody or the antigen binding fragment thereof can be combined with the human uPAR protein with high affinity, and can trigger anti-tumor specific immune response.

Inventors

• SONG JIANGBO
• TONG LI
• LEI YING
• PENG FEI

Assignees

• 上海宏成药业有限公司

Dates

Publication Date

20260508

Application Date

20251208

Claims (11)

1. 1. An anti-uPAR antibody or antigen binding fragment thereof, wherein said antibody or antigen binding fragment thereof comprises a heavy chain variable region comprising heavy chain complementarity determining regions HCDR1, HCDR2 and HCDR3 and a light chain variable region comprising light chain complementarity determining regions LCDR1, LCDR2 and LCDR3, wherein, The amino acid sequence of the HCDR1 is shown as SEQ ID NO. 14, The amino acid sequence of the HCDR2 is shown as SEQ ID NO. 10, The amino acid sequence of the HCDR3 is shown as SEQ ID NO. 4, The amino acid sequence of the LCDR1 is shown as SEQ ID NO. 6, The amino acid sequence of the LCDR2 is shown as SEQ ID NO. 7, The amino acid sequence of the LCDR3 is shown as SEQ ID NO. 8, or The amino acid sequence of the HCDR1 is shown as SEQ ID NO. 14, The amino acid sequence of the HCDR2 is shown as SEQ ID NO. 10, The amino acid sequence of the HCDR3 is shown as SEQ ID NO. 12, The amino acid sequence of the LCDR1 is shown as SEQ ID NO. 17, The amino acid sequence of the LCDR2 is shown as SEQ ID NO. 7, The amino acid sequence of the LCDR3 is shown in SEQ ID NO. 8.
2. 2. The antibody or antigen-binding fragment thereof according to claim 1, wherein, The amino acid sequence of the heavy chain variable region has at least 90% sequence identity to the sequence shown in SEQ ID NO. 13, the amino acid sequence of the light chain variable region has at least 90% sequence identity to the sequence shown in SEQ ID NO. 5, or The amino acid sequence of the heavy chain variable region has at least 90% sequence identity with the sequence shown in SEQ ID NO. 15, and the amino acid sequence of the light chain variable region has at least 90% sequence identity with the sequence shown in SEQ ID NO. 16.
3. 3. The antibody or antigen-binding fragment thereof according to claim 1, wherein, The amino acid sequence of the heavy chain variable region is shown as SEQ ID NO. 13, the amino acid sequence of the light chain variable region is shown as SEQ ID NO. 5, or The amino acid sequence of the heavy chain variable region is shown as SEQ ID NO. 15, and the amino acid sequence of the light chain variable region is shown as SEQ ID NO. 16.
4. 4. The antibody or antigen-binding fragment thereof of claim 2, further comprising a heavy chain constant region, a light chain constant region, an Fc region, or a combination thereof, wherein the light chain constant region is a kappa chain or lambda chain constant region, the heavy chain constant region being selected from the group consisting of IgG, igM, igA, igE or IgD classes.
5. 5. The antibody or antigen-binding fragment thereof according to claim 4, wherein the antibody or antigen-binding fragment thereof further comprises a heavy chain constant region having an amino acid sequence shown in SEQ ID NO. 18 and a light chain constant region having an amino acid sequence shown in SEQ ID NO. 19.
6. 6. The antibody or antigen-binding fragment thereof according to any one of claims 1-5, wherein the antigen-binding fragment is F (ab ') 2 、F(ab) 2 , fab', fab, fv, or scFv.
7. 7. A biomaterial selected from the following (a) - (c) (A) A nucleic acid molecule encoding the antibody or antigen-binding fragment thereof of any one of claims 1-6; (b) A recombinant vector comprising (a) the nucleic acid molecule; (c) A recombinant cell comprising (a) the nucleic acid molecule and/or (b) the recombinant vector.
8. 8. A method of making the antibody or antigen-binding fragment thereof of any one of claims 1-6, the method comprising culturing a recombinant cell comprising a nucleic acid molecule encoding the antibody or antigen-binding fragment thereof of any one of claims 1-6 under conditions suitable for expression of the antibody.
9. 9. A composition comprising the antibody or antigen-binding fragment thereof of any one of claims 1-6 or the biomaterial of claim 7.
10. 10. Use of an antibody or antigen-binding fragment thereof according to any one of claims 1-6, a biomaterial according to claim 7 and/or a composition according to claim 9 for the preparation of a product as shown in any one of the following: (a) Reagents for detecting uPAR; (b) A medicament for preventing and/or treating a disease associated with abnormal expression of uPAR; wherein the disease associated with abnormal expression of uPAR is cancer selected from melanoma, pancreatic cancer, triple negative breast cancer, colorectal cancer or glioblastoma.
11. 11. The use of claim 10, wherein the pancreatic cancer is pancreatic ductal adenocarcinoma.

Description

Anti-urokinase plasminogen activator receptor antibodies and uses thereof Technical Field The invention belongs to the technical field of biology, and relates to an anti-urokinase plasminogen activator receptor antibody and application thereof. Background UPA (urokinase-type plasminogen activator) is a proteolytic enzyme that promotes the fibrinolysis process. Its main function is to promote the conversion of plasminogen (plasmin) to plasmin (plasmin), which is responsible for degrading fibrin, dissolving thrombus and tissue fibers. In addition to its role in the fibrinolytic system, uPA is also associated with cell migration, invasion and tumor growth spread. uPAR is a receptor for uPA and is present on the surface of cell membranes. It binds to uPA to form a complex that promotes uPA activity on the cell surface, thereby regulating cell migration, invasion and fusion. uPAR is also associated with biological processes such as cell adhesion, signal transduction, and inflammation. Studies have shown that the uPA-uPAR system, consisting of urokinase-type plasminogen activator (urokinase-type plasminogen activator, uPA), urokinase-type plasminogen activator receptor (urokinase-type plasminogen activator receptor, uPAR) and urokinase-type plasminogen activator inhibitor (plasminogen activator inhibitor, PAI), plays an important role in the development and progression of tumors. UPAR is a high affinity receptor for urokinase-type plasminogen activator (uPA, also known as PLAU) anchored to the cell membrane by glycosyl phosphatidylinositol (glycosylphosphatidylinositol, GPI). The extracellular region comprises the D1, D2, D3 domains, and the D1-D2 junction can be sheared to produce D1 and D2-D3, wherein D1 alone can also bind uPA, but with an affinity reduced by at least 1500-fold when intact uPAR is bound. D2-D3 has the same chemotactic properties as uPA and can bind to GPCR protein FPRL1 to transmit chemotactic signals. uPAR can also be totally detached from the membrane, forming soluble suPAR, which is considered an indicator of tumor prognosis. UPA as ligand, initially the inactive zymogen pro-uPA, can be activated upon binding to uPAR, forming a double-stranded structure with an active disulfide linkage. After uPAR is combined with uPA, the activation of plasminogen and the degradation of a plurality of ECM proteins are caused, the connection of extracellular matrixes is not tight, so that the metastasis of tumor cells is triggered, and cells release ECM related growth factors, thereby not only reversely enhancing the expression of uPA and uPAR, but also inducing the regeneration of tumor blood vessels and the transformation of epithelial mesenchymal stem, and in addition, the proliferation of cells can be regulated and controlled, the apoptosis of cells can be prevented, and the method plays an important role in the occurrence and development of tumors. In addition, uPAR can promote extracellular matrix protein degradation through combining with uPA, can also combine with integrin alpha 5 beta 1, alpha 3 beta 1 or alpha v beta 3 to form a complex and vitronectin (Vitronection) to mediate RAS/RAF/MEK/ERK, PI3K/AKT and other cell signal pathways to activate, and the effects can not only enhance proliferation, migration and invasion capacity of tumor cells, but also inhibit apoptosis of tumor cells and promote angiogenesis of tumor tissues. Recent evidence suggests that the signaling pathway of uPAR activation helps cancer cells to evade and reduce the cytotoxic effects of anticancer drugs. The increased expression of the gene encoding uPAR (PLAUR) in cancer may be regulated by different mechanisms. Transcription factors such as Sp1, NF-. Kappa. B, TCF and hypoxia inducible factor 1α are often activated by different types of cancer-associated signaling pathways, which bind to cis-acting elements upstream of the uPAR gene, triggering their high expression in cancer. It slows down the growth of mouse melanoma by inhibiting the expression of uPA, uPAR, MMP-2, MMP-9, etc. in the uPA-uPAR system. Urokinase plasminogen activator receptor (uPAR) is expressed on a variety of cell types including macrophages, neutrophils, endothelial cells and, importantly, on many cancer cells. Expression of uPAR in malignant tissue is significantly up-regulated compared to normal tissue, with particularly high expression observed in Pancreatic Ductal Adenocarcinoma (PDAC), triple negative breast cancer, colorectal cancer and glioblastoma. Importantly, uPAR expression is closely related to adverse clinical outcomes for a variety of cancer types, making it an attractive prognostic biomarker and therapeutic target. Limited expression of receptors in normal tissues (mainly limited to immune cells at the site of inflammation) provides a valuable therapeutic window for antibody-based targeting strategies. Many uPAR-expressing cancers remain under-standard of care, with limited treatment options and poor long-term results. Current treatment