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CN-119912575-B - CA15-3 antigen binding protein and application thereof

CN119912575BCN 119912575 BCN119912575 BCN 119912575BCN-119912575-B

Abstract

The invention provides a CA15-3 antigen binding protein and application thereof, wherein the CA15-3 antigen binding protein comprises a heavy chain variable region and a light chain variable region, the heavy chain variable region comprises CDR3 with a sequence shown as SEQ ID NO.7 or SEQ ID NO.13, and the light chain variable region comprises CDR3 with a sequence shown as SEQ ID NO.10 or SEQ ID NO. 16. The CA15-3 antigen binding protein is a rabbit monoclonal antibody, and compared with a mouse antibody and a polyclonal antibody, the rabbit antibody has higher affinity and stronger specificity naturally, the antibody obtained by combination has strong specificity and high accuracy, and the obtained CA15-3 antigen binding protein can be matched and applied to diagnosis of breast cancer.

Inventors

  • YIN WENFANG
  • LI JING
  • ZHENG YUE
  • DONG YULIANG
  • XIONG SICHI

Assignees

  • 深圳华大生命科学研究院

Dates

Publication Date
20260505
Application Date
20231030

Claims (9)

  1. 1. An anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof, characterized in that the monoclonal antibody or antigen-binding fragment thereof comprises a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region comprises a CDR1 of a sequence shown as SEQ ID NO.5, a CDR2 of a sequence shown as SEQ ID NO.6, a CDR3 of a sequence shown as SEQ ID NO.7, and the light chain variable region comprises a CDR1 of a sequence shown as SEQ ID NO.8, a CDR2 of a sequence shown as SEQ ID NO.9, and a CDR3 of a sequence shown as SEQ ID NO. 10; Or the heavy chain variable region comprises a CDR1 with a sequence shown as SEQ ID NO.11, a CDR2 with a sequence shown as SEQ ID NO.12, a CDR3 with a sequence shown as SEQ ID NO.13, and the light chain variable region comprises a CDR1 with a sequence shown as SEQ ID NO.14, a CDR2 with a sequence shown as SEQ ID NO.15, and a CDR3 with a sequence shown as SEQ ID NO. 16.
  2. 2. The anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof according to claim 1, wherein the sequence of the heavy chain variable region is the sequence shown in SEQ ID NO.1 and the sequence of the light chain variable region is the sequence shown in SEQ ID NO.2, or, The sequence of the heavy chain variable region is shown as SEQ ID NO.3, and the sequence of the light chain variable region is shown as SEQ ID NO. 4.
  3. 3. The anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof according to claim 1, wherein the constant region of the monoclonal antibody is a rabbit-derived constant region.
  4. 4. A nucleic acid molecule encoding the anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof according to any one of claims 1-3.
  5. 5. An expression vector comprising the nucleic acid molecule of claim 4.
  6. 6. A host cell comprising at least one copy of the expression vector of claim 5, or having integrated on its genome the nucleic acid molecule of claim 4.
  7. 7. A reagent for detecting the CA15-3 protein in a sample, comprising the anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof according to any one of claims 1-3.
  8. 8. A kit comprising the anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof according to any one of claims 1-3, or the reagent for detecting a CA15-3 protein in a sample according to claim 7.
  9. 9. Use of an anti-CA 15-3 monoclonal antibody or antigen-binding fragment thereof according to any one of claims 1-3 for the preparation of a breast cancer detection product.

Description

CA15-3 antigen binding protein and application thereof Technical Field The invention belongs to the technical field of biological pharmacy, and particularly relates to a CA15-3 antigen binding protein and application thereof. Background CA15-3 (cancer antigen 15-3, also known as Mucin1, MUC1, EMA, MCD, PEM, PUM, KL-6 and MAM 6) is a Mucin family member, a type I transmembrane protein with a highly glycosylated extracellular domain extending from the cell surface by 200-500 nm. CA15-3 consists of two subunits, the N-terminal subunit of the ectodomain and the C-terminal subunit of the cytoplasmic domain. The molecular weight of the core protein is 120-220 kDa, and the glycosylated part is larger than 400 kDa. CA15-3 is the first found breast cancer related antigen, is positioned on the surface of tumor cells, and when the cells become cancerous, the activities of protease and sialidase on the cell membranes are increased, and the cytoskeleton is destroyed, so that the cell antigens are withered, released into the blood, and the content of serum CA15-3 is increased. The CA15-3 of the breast cancer patients is increased, the sensitivity of the breast cancer at the early stage is 60 percent, and the sensitivity of the breast cancer at the late stage is 80 percent. CA15-3 has important value for the curative effect observation, prognosis judgment, recurrence and metastasis diagnosis of breast cancer. CA15-3 also has a certain positive rate on other malignant tumors. Such as lung cancer, colon cancer, pancreatic cancer, ovarian cancer, cervical cancer or primary liver cancer. The development process of the CA15-3 detection antibody mainly comprises the following steps of (1) preparing a main immunogen generally by adopting a natural antigen, polypeptide or cells expressing CA15-3 and the like, (2) immunizing an immunized animal by selecting a proper immunized animal, generally by adopting a mouse, a rabbit and the like, (3) injecting the immunogen into the immunized animal to excite the immunized animal to generate a CA15-3 specific antibody, (4) screening and identifying the CA15-3 specific antibody with specificity and affinity by using screening methods such as phage display, single cell sorting and the like, and (5) further identifying and evaluating candidate antibodies, including affinity measurement, flow cytometry analysis, cloning, antibody optimization and improvement. But the current anti-CA 15-3 protein antibodies are less, and the price of purchasing imported brands is high. On the other hand, the sensitivity of the CA15-3 pairing antibody pair is higher, so the monoclonal antibody capable of specifically binding the CA15-3 protein is provided, and has important application value in the diagnosis of breast cancer. Disclosure of Invention Aiming at the defects of the prior art, the invention aims to provide a CA15-3 antigen binding protein and application thereof. The CA15-3 antigen binding protein is a rabbit monoclonal antibody, and compared with a mouse antibody and a polyclonal antibody, the rabbit antibody has higher affinity and stronger specificity naturally, and the antibody obtained by combination has strong specificity and high accuracy. The obtained antibody can be used for diagnosing breast cancer. In order to achieve the aim of the invention, the invention adopts the following technical scheme: in a first aspect, the invention provides a CA15-3 antigen binding protein, characterized in that the CA15-3 antigen binding protein comprises a heavy chain variable region comprising CDR3 having a sequence as shown in SEQ ID NO.7 or SEQ ID NO.13 and a light chain variable region; The light chain variable region comprises a CDR3 having a sequence as shown in SEQ ID NO.10 or SEQ ID NO. 16. Preferably, the heavy chain variable region comprises CDR1 having a sequence as set forth in SEQ ID No.5 or SEQ ID No. 11. Preferably, the heavy chain variable region comprises CDR2 having a sequence as set forth in SEQ ID No.6 or SEQ ID No. 12. Preferably, the light chain variable region comprises CDR1 having a sequence as set forth in SEQ ID No.8 or SEQ ID No. 14. Preferably, the light chain variable region comprises CDR2 having a sequence as set forth in SEQ ID No.9 or SEQ ID No. 15. Preferably, the heavy chain variable region comprises a CDR1 having a sequence as shown in SEQ ID NO.5, a CDR2 having a sequence as shown in SEQ ID NO.6 and a CDR3 having a sequence as shown in SEQ ID NO.7, and the light chain variable region comprises a CDR1 having a sequence as shown in SEQ ID NO.8, a CDR2 having a sequence as shown in SEQ ID NO.9 and a CDR3 having a sequence as shown in SEQ ID NO.10, or, The heavy chain variable region comprises a CDR1 having a sequence as shown in SEQ ID NO.11, a CDR2 having a sequence as shown in SEQ ID NO.12 and a CDR3 having a sequence as shown in SEQ ID NO.13, and the light chain variable region comprises a CDR1 having a sequence as shown in SEQ ID NO.14, a CDR2 having a sequence as shown in