Epitope of RSV fusion protein and antibody recognizing the same
Inventors
Zheng, Zizheng • McLellan, Jason S. • Chen, Man • Zhao, Min • Huang, Liangmin • Graham, Barney S. • Xia, Ningshao
Assignees
Yang Sheng Tang Co Ltd • Xiamen University • US Department of Health and Human Services
Publication Number
US-9856313-B2
Publication Date
2018-01-02
Expiration Date
2034-03-17
Interested in licensing this patent?
MTEC can help explore whether this patent might be available for licensing for your application.
Abstract
The present invention relates to an epitope peptide (or a variant thereof) which can be used in the prevention of respiratory syncytial virus (RSV) infection, a recombinant protein comprising the epitope peptide (or a variant thereof) and a carrier protein, and uses of the epitope peptide (or a variant thereof) and the recombinant protein. The present invention also relates to an antibody against the epitope peptide, a cell line for generating the antibody, and uses thereof. Furthermore, the present invention also relates to a vaccine or a pharmaceutical composition comprising the recombinant protein or the antibody according to the invention, for preventing one or more symptoms associated with RSV infection.
Core Innovation
The invention provides an isolated epitope peptide or a variant thereof derived from the respiratory syncytial virus (RSV) fusion protein (F protein), specifically encompassing amino acid residues from positions 148 to 216, with at least residues from positions 196 to 209 included. This epitope is preferentially present with its native steric conformation in the pre-fusion (pre-F) conformation of F protein, which is metastable and key to RSV infection. The invention further includes recombinant proteins comprising this epitope peptide fused to a carrier protein to enhance immunogenicity, nucleic acid molecules encoding these peptides or proteins, vectors, host cells for protein expression, and vaccines or pharmaceutical compositions comprising these components for preventing RSV infection or related diseases such as pneumonia.
In addition, the invention provides monoclonal antibodies and antigen binding fragments that specifically bind to the above-defined epitope on the RSV F protein, especially those that recognize the epitope present in its pre-F conformation and do not bind or bind minimally to the post-fusion (post-F) conformation. These antibodies, such as the monoclonal antibody 5C4, demonstrate higher neutralizing activity against RSV than previously known antibodies like palivizumab (Synagis), and can stabilize and maintain the pre-F conformation of the F protein, a key factor in inducing a strong immune response. Methods for producing these antibodies, nucleic acid molecules encoding them, vectors, and host cells for antibody production are also provided, along with pharmaceutical compositions and kits containing these antibodies.
The problem addressed by the invention stems from the significant health burden posed by RSV infections, especially in infants and the elderly, for which no safe and effective vaccines currently exist. Existing neutralizing antibodies such as palivizumab have limited neutralizing titers, are costly, and have application restricted to high-risk populations. The difficulty in studying the pre-F conformation of RSV F protein, due to its metastability and lack of an available stable structure, has hindered the development of improved vaccines and antibodies targeting this critical viral fusion protein form. The invention overcomes these problems by identifying novel epitopes on the pre-F conformation that allow for the generation of highly neutralizing antibodies that stabilize pre-F protein, leading to improved prophylactic or therapeutic agents against RSV.
Claims Coverage
There is one independent claim covering a monoclonal antibody recognizing specific epitopes of RSV fusion protein and related compositions and methods.
Monoclonal antibody recognizing defined RSV F protein epitopes
A monoclonal antibody and its antigen binding fragments that specifically bind to amino acid residues 148-216 of RSV fusion protein or a fragment thereof, and/or residues 62-69 or 62-76 of RSV fusion protein, comprising specific complementarity determining regions (CDRs) as set forth in SEQ ID NOs:20-25, with the F protein sequence as SEQ ID NO:15.
Isolated nucleic acid molecule encoding the monoclonal antibody
An isolated nucleic acid molecule encoding the monoclonal antibody or antigen binding fragment described above.
Vector comprising the isolated nucleic acid molecule
A vector comprising the isolated nucleic acid molecule encoding the monoclonal antibody or antigen binding fragment.
Host cell comprising the nucleic acid molecule or vector
A host cell comprising the isolated nucleic acid molecule or the vector comprising the nucleic acid molecule.
Hybridoma cell line producing the monoclonal antibody
A hybridoma cell line RSV-Y-5C4-2 deposited at CCTCC with accession number CCTCC NO: C2012147, producing the monoclonal antibody.
Method for stabilizing pre-F protein
A method for stabilizing pre-F protein by contacting it with the monoclonal antibody or antigen binding fragment.
Kit comprising the monoclonal antibody or antigen binding fragment
A kit comprising the monoclonal antibody or antigen binding fragment.
Pharmaceutical composition comprising the monoclonal antibody
A pharmaceutical composition comprising the monoclonal antibody or antigen binding fragment and a pharmaceutically acceptable carrier or excipient.
Method for preventing or treating RSV infection
A method for preventing or treating RSV infection by administering a prophylactically or therapeutically effective amount of the monoclonal antibody or antigen binding fragment.
Method for expressing pre-F protein or antigen-antibody complex
A method for expressing pre-F protein or an antigen-antibody complex by co-expressing nucleic acids encoding the monoclonal antibody or antigen binding fragment and F protein in a cell.
Kit comprising nucleic acids encoding the monoclonal antibody and F protein
A kit comprising nucleic acids encoding the monoclonal antibody or antigen binding fragment and nucleic acid encoding F protein.
Additional monoclonal antibody features
The monoclonal antibody can comprise heavy chain variable region SEQ ID NO:17 and light chain variable region SEQ ID NO:19; be selected from Fab, Fab′, F(ab′)2, Fd, Fv, dAb, complementary determining region fragment, single chain antibodies (e.g. scFv), mouse, humanized, chimeric (e.g. human-mouse), or bispecific/poly-specific antibodies; comprise non-CDR region from non-murine species, preferably human; specifically bind RSV with neutralizing activity; do not bind post-F protein but stabilize pre-F protein; and may be derived from hybridoma cell line 5C4 deposited at CCTCC.
The claims cover a monoclonal antibody against a novel RSV F protein epitope comprising residues 148-216 and/or 62-76, nucleic acids, vectors, host cells, hybridoma producing the antibody, methods of using the antibody to stabilize pre-F protein and treat RSV infection, and associated kits and pharmaceutical compositions.
Stated Advantages
The discovery of a new epitope of RSV fusion protein that plays an important role in stabilizing and maintaining the pre-F conformation of the protein.
The monoclonal antibodies specifically recognizing this epitope exhibit higher neutralizing activity against RSV compared to prior known antibodies.
The epitope peptide or recombinant protein comprising it serves as an effective protein vaccine for preventing RSV infection and diseases associated with RSV infection.
The monoclonal antibodies and antigen binding fragments can be used at lower amounts due to higher neutralizing activity, enabling effective prevention or treatment of RSV infection with reduced doses.
Documented Applications
Use as a protein vaccine for preventing RSV infection or associated diseases such as infantile pneumonia.
Production of neutralizing monoclonal antibodies for prevention or treatment of RSV infection.
Use in methods for preventing, treating or inhibiting RSV infection or diseases associated with RSV infection.
Use of the monoclonal antibody or antigen binding fragments in kits and pharmaceutical compositions for RSV diagnosis, detection of pre-F protein, and stabilization of pre-F protein.
Gene vaccines comprising nucleic acids encoding the epitope peptide, recombinant protein, or antibodies for preventing or treating RSV infection.
Expression of pre-F protein or antigen-antibody complexes by co-expression of nucleic acids encoding the monoclonal antibody and F protein.
Interested in licensing this patent?