CN-121974989-A - Preferred epitope peptide of CCHFV Gc, tandem multi-epitope vaccine, expression vector and application

CN121974989ACN 121974989 ACN121974989 ACN 121974989ACN-121974989-A

Abstract

The invention belongs to the technical field of microbial immunity technology and DNA vaccine, and in particular relates to a preferential epitope peptide of C-terminal end (CCHFV Gc) of a Crimea-Congo hemorrhagic fever virus envelope glycoprotein, a tandem multi-epitope vaccine, an expression vector and application. The preferred epitope peptide consists of any one of amino acid sequences shown in SEQ ID NO. 1-SEQ ID NO.21, and is a preferred epitope with high affinity, strong immunogenicity and interspecific and intraspecies conservation. The invention also synthesizes the preferred epitope in series through the linker to form a serial multi-epitope vaccine, so that the vaccine enters cells to be expressed to form recombinant proteins, further activates T lymphocytes and induces cellular immune response, and uses the serial multi-epitope vaccine to evaluate the vaccine in animals, and proves that the vaccine can effectively induce anti-CCHFV specific cellular immune response and application safety in BALB/c mice. The invention is helpful for understanding the immunobiology of CCHFV Gc and perfecting the design of epitope vaccine aiming at the virus in the future.

Inventors

ZHANG XIYANG
ZHANG CHUNMEI
ZHANG BIN
SUN YUANJIE
ZHANG YUSI
JIANG DONGBO
ZHANG YUXUAN
LI JIANCHANG
WANG YONGKAI
SUN BAOZENG
WANG JING
GUAN ENQI
JIA YU

Assignees

中国人民解放军空军军医大学

Dates

Publication Date: 20260505
Application Date: 20260209

Claims (9)

1. A preferred epitope peptide of CCHFV Gc is characterized in that the amino acid sequence is shown in any one of SEQ ID NO. 1-SEQ ID NO. 21.
2. A tandem multi-epitope vaccine engineered from the preferred epitope peptide of CCHFV Gc of claim 1, constructed according to the following method: The tandem multi-epitope vaccine is prepared by connecting sixteen peptide segments on CCHFV Gc with the amino acid sequence shown in SEQ ID NO. 1-SEQ ID NO.21 through a connector; The nucleotide sequence of sixteen peptide fragments is as follows: TSLSIEAPW,LEERTGISW,MYSPVFEYL,LHKEWPHSRNWRCNPTW,DVKDLFTDY,FVKWKVEYIKTEAIVCVEL,RFNLGPVTI,IEEGFFDLM,EPHFNTSWM,MGDWPSCTY,EPDELTVHV,SLCFYIVER,QPQSILIEHKGTI,MLSGIFGNV,APFILLILF,RRTRGLFKY.
3. the tandem multi-epitope vaccine of claim 2, wherein the amino acid sequence of said tandem multi-epitope vaccine is set forth in SEQ ID No. 22.
4. The tandem multi-epitope vaccine of claim 2, wherein the nucleotide sequence of said tandem multi-epitope vaccine is set forth in SEQ ID No. 24.
5. An expression vector pVAX1-CCHFV-Gc21p comprising the nucleotide sequence of the tandem multi-epitope vaccine of claim 4.
6. The expression vector pVAX1-CCHFV-Gc21p of claim 5, wherein the expression vector pVAX1-CCHFV-Gc21p is constructed according to the following method: synthesizing a nucleotide sequence shown as SEQ ID NO.24, cloning into a pVAX1 vector, transforming bacteria, and finally screening and verifying to complete the construction of an expression vector.
7. Use of a preferred epitope peptide of CCHFV Gc according to claim 1, a tandem multi-epitope vaccine according to claim 2 or an expression vector pVAX1-CCHFV-Gc21p according to claim 4 for the preparation of a product for the prevention or treatment of CCHFV infection.
8. The use according to claim 7, wherein said product is obtained by compounding a preferred epitope peptide of said CCHFV Gc, a tandem multi-epitope vaccine or an expression vector as an active substance with a vaccine adjuvant.
9. The use according to claim 8, wherein the vaccine adjuvant is an aluminium adjuvant, an oil emulsion adjuvant or a cytokine adjuvant.

Description

Preferred epitope peptide of CCHFV Gc, tandem multi-epitope vaccine, expression vector and application Technical Field The invention belongs to the technical field of microbial immunity, and particularly relates to a preferential epitope peptide of a C-terminal (CCHFV Gc) of a Crimea-Congo hemorrhagic fever virus envelope glycoprotein, a tandem multi-epitope vaccine, an expression vector and application. Background Crimedes-Congo hemorrhagic fever virus (Crimean-Congo hemorrhagic fever virus, CCHFV) is a widely transmitted pathogen that is increasingly prevalent due to tick spread. CCHFV can cause crimia-congo hemorrhagic fever (Crimean-Congo Hemorrhagic Fever, CCHF) with up to 40% mortality, and no specific vaccine is currently available. CCHFV is classified as a biosafety level-4 (BSL-4) pathogen and is classified as a high priority pathogen by the national institutes of health (NIH/NIAID) and the World Health Organization (WHO). CCHFV is a member of the genus orthoviridae, the family of the neloviridae, and has a three-piece negative strand RNA genome. Wherein the M-segment encodes a Glycoprotein Precursor (GPC), and upon cleavage, gn, gc, etc. are formed. The present data indicate that both Gn and Gc can be recognized by immune cells and provide immune protection, and immune responses against Gc result in prolonged survival. Furthermore, gc-mediated immune responses were also demonstrated in infected individuals. Thus Gc is considered currently the most valuable anti-CCHFV immune target. Cytotoxic T Lymphocytes (CTLs) restricted by major histocompatibility complex (major histocompatibility complex, MHC) class I molecules are important effector cells against viral infections, T cell recognition epitopes and induction of immune responses play a critical role in the immune response of the body. During the viral-host symbiotic process, viruses interfere with the killing activity of CTLs in a variety of ways, such as modifying or reducing T cell-recognizable protein sequences or immune epitopes, thereby evading host clearance. These interference patterns impair the immune balance and immunity of the host. Only high affinity peptides that bind to MHC class I molecules are possible to activate cells and trigger immune responses. Thus, high affinity epitopes are critical for the immune response of T cells against CCHFV. At the same time, the key factor in "population immunity" of vaccine molecules against widely mutated strains of virus, and therefore, conserved epitopes can provide long-term immune protection for the host during virus-host symbiosis. Although current predictions and screens for viral epitopes have formed a series of general methods, such as combinations of computational tools based on MHC binding affinity, immunogenicity and conservation, the limited exploration of pathogenesis, host-virus interactions and immune response mechanisms due to sporadic and lack of systematic studies of the outbreak of crimia congo fever, the direct application of current general epitope screening methods to crimia congo fever viruses is also significantly limited, and currently it is difficult to obtain preferred epitopes that have both high affinity, strong immunogenicity, conservation between species and that are effective in eliciting cellular immune responses, limiting CCHFV therapies and containment. Therefore, aiming at virology and immunology characteristics of the CCHFV, the immune protection mechanism of the host to the CCHFV is deeply analyzed, and a key immune preferential epitope peptide is searched for, so that a foundation is laid for developing more effective CCHFV treatment and inhibition strategies. Disclosure of Invention In order to solve the technical problems, the invention provides a preferential epitope peptide of the C-terminal end of a Crimea-Congo hemorrhagic fever virus envelope glycoprotein, a tandem multi-epitope vaccine and application, wherein the preferential epitope peptide and the tandem multi-epitope vaccine have good cellular immunity efficacy in various mice. The specific technical scheme provided by the invention is as follows: In a first aspect, the invention provides a preferred epitope peptide of CCHFV Gc, the amino acid sequence of which is shown in any one of SEQ ID NO. 1-SEQ ID NO. 21. SEQ ID NO.1：TSLSIEAPW;SEQ ID NO.2：LEERTGISW;SEQ ID NO.3：MYSPVFEYL;SEQ ID NO.4：LHKEWPHSR;SEQ ID NO.5：WPHSRNWRC;SEQ ID NO.6：RNWRCNPTW;SEQ ID NO.7：DVKDLFTDY;SEQ ID NO.8：FVKWKVEYI;SEQ ID NO.9：VEYIKTEAI;SEQ ID NO.10：TEAIVCVEL;SEQ ID NO.11：RFNLGPVTI;SEQ ID NO.12;IEEGFFDLM;SEQ ID NO.13：EPHFNTSWM;SEQ ID NO.14：MGDWPSCTY;SEQ ID NO.15：EPDELTVHV;EQ ID NO.16：SLCFYIVER;SEQ ID NO.17：QPQSILIEH;SEQ ID NO.18：ILIEHKGTI;SEQ ID NO.19：MLSGIFGNV;SEQ ID NO.20;APFILLILF;SEQ ID NO.21：RRTRGLFKY. The 21 preferred epitope peptides provided by the invention not only have the comprehensive advantages of high affinity, strong immunogenicity, broad-spectrum conservation and low safety risk, but also successfully overcome