CN-122011171-A - Anti-MERS virus monoclonal antibody, preparation method and application thereof

Abstract

The invention discloses an anti-MERS virus monoclonal antibody, a preparation method and application thereof, and belongs to the field of biomedicine. The monoclonal antibody or antigen binding fragment thereof specifically binds to the S1 protein of middle east respiratory syndrome virus, wherein the monoclonal antibody or antigen binding fragment thereof comprises a) a heavy chain variable region comprising HCDR1 as shown in SEQ ID NO. 3, HCDR2 as shown in SEQ ID NO. 4 and HCDR3 as shown in SEQ ID NO. 5, and b) a light chain variable region comprising LCDR1 as shown in SEQ ID NO. 10, LCDR2 as shown in SEQ ID NO. 11 and LCDR3 as shown in SEQ ID NO. 12.

Inventors

• ZHAO GUANGYU
• YIN QI
• HAN GENCHENG
• LI GE
• XIAO HE
• WANG YUAN
• LI MIN
• HAN XUELIAN

Assignees

• 中国人民解放军军事科学院军事医学研究院

Dates

Publication Date

20260512

Application Date

20260320

Claims (10)

1. 1. An isolated monoclonal antibody or antigen-binding fragment thereof that specifically binds to the middle east respiratory syndrome coronavirus S1 protein, wherein the monoclonal antibody or antigen-binding fragment thereof comprises: a) A heavy chain variable region comprising HCDR1 as shown in SEQ ID NO. 3, HCDR2 as shown in SEQ ID NO. 4 and HCDR3 as shown in SEQ ID NO. 5, and B) A light chain variable region comprising LCDR1 as set forth in SEQ ID NO. 10, LCDR2 as set forth in SEQ ID NO. 11 and LCDR3 as set forth in SEQ ID NO. 12.
2. 2. The isolated monoclonal antibody or antigen-binding fragment thereof according to claim 1, wherein the heavy chain variable region comprises an amino acid sequence as set forth in SEQ ID No. 1 and the light chain variable region comprises an amino acid sequence as set forth in SEQ ID No. 2.
3. 3. An isolated nucleic acid molecule encoding the monoclonal antibody or antigen-binding fragment thereof of claim 1 or 2.
4. 4. An expression vector comprising the nucleic acid molecule of claim 3.
5. 5. A host cell comprising the expression vector of claim 4.
6. 6. The host cell of claim 8, wherein the host cell is a CHO cell.
7. 7. A pharmaceutical composition comprising the isolated monoclonal antibody or antigen-binding fragment thereof of claim 1 or 2, and a pharmaceutically acceptable carrier.
8. 8. Use of an isolated monoclonal antibody or antigen binding fragment thereof according to claim 1 or 2 in the manufacture of a medicament for the prevention and/or treatment of a coronavirus infection of the middle east respiratory syndrome.
9. 9. A method of making the monoclonal antibody or antigen binding fragment thereof of claim 1 or 2, the method comprising the steps of: Culturing the host cell of claim 5 or 6 under conditions suitable for expression of the monoclonal antibody or antigen-binding fragment thereof, and Recovering the monoclonal antibody or antigen binding fragment thereof from the host cell culture.
10. 10. The method of preparing the monoclonal antibody or antigen-binding fragment thereof according to claim 9, further comprising the step of purifying the monoclonal antibody or antigen-binding fragment thereof recovered from the host cell culture, the purifying step comprising the steps of: a) Subjecting the host cell culture to clarification; b) Loading the sample treated in step a) onto a Protein a affinity chromatography medium to capture the monoclonal antibody or antigen binding fragment thereof; c) Eluting said monoclonal antibody or antigen binding fragment thereof from said Protein A affinity chromatography medium to obtain an eluate, and D) Subjecting the eluate obtained in step c) to tangential flow ultrafiltration for concentrating and/or buffer displacement of the monoclonal antibody or antigen binding fragment thereof.

Description

Anti-MERS virus monoclonal antibody, preparation method and application thereof Technical Field The invention relates to the biomedical field, in particular to an anti-MERS virus monoclonal antibody, a preparation method and application thereof. Background At present, the research on therapeutic antibodies against MERS-CoV at home and abroad mainly focuses on targeting the Receptor Binding Domain (RBD) of viral spike protein (S protein). For example, the m336 antibody (developed cooperatively by double denier university/NIH) is a fully human monoclonal antibody, has extremely high neutralizing activity to pseudoviruses (IC 50.about.0.005. Mu.g/mL), has an affinity reaching the picomolar level, and is one of representative candidate drugs. Such as REGN3048, also showed some neutralizing activity, but most studies remain in the laboratory discovery and preclinical function validation stage. The prior art has focused mainly on the discovery of antibody molecules themselves, affinity optimisation and in vitro neutralisation activity enhancement. In addition, most high-performance antibodies lack matched stable and high-expression cell lines and mature purification processes, and large-scale production is difficult to realize. Disclosure of Invention Aiming at the defects of the prior art, the invention provides an anti-MERS virus monoclonal antibody, a preparation method and application thereof. The aim of the invention can be achieved by the following technical scheme: in a first aspect the invention relates to an isolated monoclonal antibody or antigen binding fragment thereof which specifically binds to the S1 protein of the middle eastern respiratory syndrome coronavirus, wherein the monoclonal antibody or antigen binding fragment thereof comprises: a) A heavy chain variable region comprising HCDR1 as shown in SEQ ID NO. 3, HCDR2 as shown in SEQ ID NO. 4 and HCDR3 as shown in SEQ ID NO. 5, and B) A light chain variable region comprising LCDR1 as set forth in SEQ ID NO. 10, LCDR2 as set forth in SEQ ID NO. 11 and LCDR3 as set forth in SEQ ID NO. 12. Alternatively, the heavy chain variable region comprises the amino acid sequence shown as SEQ ID NO. 1 and the light chain variable region comprises the amino acid sequence shown as SEQ ID NO. 2. In a second aspect, the invention relates to an isolated nucleic acid molecule encoding a monoclonal antibody or antigen binding fragment thereof as described above. In a third aspect the invention relates to an expression vector comprising a nucleic acid molecule as described above. In a fourth aspect the invention relates to a host cell comprising an expression vector as described above. Alternatively, the host cell is a CHO cell. In a fifth aspect, the invention relates to a pharmaceutical composition comprising an isolated monoclonal antibody or antigen binding fragment thereof as described above, and a pharmaceutically acceptable carrier. In a sixth aspect the invention relates to the use of an isolated monoclonal antibody or antigen binding fragment thereof as described above for the manufacture of a medicament for the prevention and/or treatment of a coronavirus infection of the middle east respiratory syndrome. In a seventh aspect, the present invention relates to a method for preparing a monoclonal antibody or antigen binding fragment thereof as described above, comprising the steps of: Culturing the above-described host cell under conditions suitable for expression of the monoclonal antibody or antigen-binding fragment thereof, and Recovering the monoclonal antibody or antigen binding fragment thereof from the host cell culture. Optionally, further comprising a step of purifying the monoclonal antibody or antigen binding fragment thereof recovered from the host cell culture, the purifying step comprising the steps of: a) Subjecting the host cell culture to clarification; b) Loading the sample treated in step a) onto a Protein a affinity chromatography medium to capture the monoclonal antibody or antigen binding fragment thereof; c) Eluting said monoclonal antibody or antigen binding fragment thereof from said Protein A affinity chromatography medium to obtain an eluate, and D) Subjecting the eluate obtained in step c) to tangential flow ultrafiltration for concentrating and/or buffer displacement of the monoclonal antibody or antigen binding fragment thereof. The invention has the beneficial effects that: The anti-MERS virus monoclonal antibody (306-1C 1) provided by the invention has excellent antigen binding capacity and virus neutralization activity, and has remarkable clinical application potential. First, at the molecular level, the antibody can specifically recognize and bind to the S1 protein of MERS coronavirus, and Surface Plasmon Resonance (SPR) detection shows that the equilibrium dissociation constant (KD) is 18.59 nM, and the characteristic of high affinity binding of the nano-molar grade is a physical basis for the strong blocking effect. Second,