CN-115779079-B - Charge-regulated antigen protein capable of enhancing synergistic immunity with adjuvant

Abstract

The invention discloses a charge regulation type antigen protein capable of enhancing the synergistic immunity with an adjuvant, which changes the synergistic effect with the charged adjuvant by accurately regulating the surface charge of the antigen protein, obviously enhances the vaccine immunity and greatly reduces the dosage of the antigen and the adjuvant. The invention also provides a plurality of charge-control type antigen protein variants designed and obtained by the method, a synergistic composition of the charge-control type antigen protein variants and an adjuvant, and application of the synergistic composition in treatment, prevention drugs or vaccines in the field of biological medicine.

Inventors

• Zai Xiaodong
• LI RUIHUA
• LI YAOHUI
• CHEN WEI
• ZHANG ZHILING
• ZHAO FANGXIN
• XU JUNJIE
• ZHANG YUE
• ZHANG JUN
• YIN YING
• YANG YILONG

Assignees

• 中国人民解放军军事科学院军事医学研究院

Dates

Publication Date

20260505

Application Date

20221001

Claims (4)

1. 1. An antigenic protein variant having an insertion of a charged amino acid fragment, wherein said antigenic protein variant is selected from the group consisting of the novel coronavirus RBD antigens as set forth in SEQ ID No. 8.
2. 2. A vaccine composition comprising the antigenic protein variant of claim 1, wherein the vaccine composition further comprises a charged adjuvant that carries a charge opposite to the charge profile of the charged amino acid fragment introduced into the antigenic protein variant.
3. 3. The vaccine composition of claim 2, wherein the charged adjuvant is selected from one or more of a charged metal salt adjuvant, a pattern recognition receptor agonist adjuvant, a liposome adjuvant, an oil emulsion adjuvant, a cytokine adjuvant, a chemokine adjuvant.
4. 4. A vaccine composition according to claim 3, characterized in that the charged metal salt adjuvant is selected from one of an aluminium hydroxide adjuvant, an aluminium-containing complex adjuvant, a manganese adjuvant or a CpG adjuvant.

Description

Charge-regulated antigen protein capable of enhancing synergistic immunity with adjuvant Technical Field The invention relates to a charge-regulated antigen protein capable of enhancing synergistic immunity with an adjuvant, belonging to the field of biological medicine. Background In recent years, epidemic situation of new emergent infectious diseases caused by SARS, MERS, avian influenza, ebola, novel coronavirus and the like is continuously exploded worldwide, and the health and social stability of people are seriously threatened. Vaccination is one of the most economical and effective means of dealing with infectious diseases. In addition, in the face of centuries of difficult problems such as tumors and Alzheimer's disease, the development of therapeutic vaccines is also an emerging strategy for coping with. At present, vaccines are mainly divided into traditional vaccines and novel vaccines according to types, wherein the traditional vaccines comprise inactivated vaccines, attenuated live vaccines and the like, and the novel vaccines mainly comprise recombinant protein vaccines, viral vector vaccines, nucleic acid vaccines and the like. The recombinant protein vaccine has the advantages of single and definite components, clear immune protection mechanism, simple preparation process, safe operation, no risk, easy large-scale preparation and production and the like. However, there are disadvantages such as poor immunogenicity of the protein antigen alone, and adjuvant synergy is often required to exert better immune efficacy. Aluminum adjuvants are widely used and vaccinated as the most classical vaccine adjuvants because of their ease of availability and low cost. Common aluminum adjuvants include aluminum hydroxide Adjuvants (AH), aluminum phosphate Adjuvants (AP), and the like, where AH is chemically crystalline aluminum oxyhydroxide and aluminum on the AH surface coordinates with an amphoteric hydroxyl group and can accept or donate protons depending on the pH of the solution. Thus, commercial AH formulations (isoelectric point 11.4) are positively charged on their surface at physiologically neutral pH (about 7.4). In contrast to AH, commercial AP formulations typically have isoelectric points of 4.6-5.6 and are negatively charged at physiologically neutral pH (about 7.4). In addition, the commonly used aluminum adjuvants also comprise a mixed system of the aluminum adjuvants and an adjuvant system consisting of the aluminum adjuvants and other adjuvant components, such AS an aluminum+CpG adjuvant system, an AS04 adjuvant system and the like. The mechanism of action of aluminum adjuvants has not been fully established at present, and it has been considered that the aluminum adjuvants adsorb antigen proteins mainly through electrostatic interactions, ligand exchange and other mechanisms, thereby exerting their immunopotentiating effects, that aluminum adjuvants micronize soluble antigens to enhance absorption through phagocytosis by dendritic cells, and lock the antigens onto antigen presenting cells while enhancing antigen presentation, and that the antigens remain at injection sites, allowing time for antigen presenting cells to be recruited by releasing cytokines and inducing local inflammatory responses. Therefore, by enhancing the electrostatic adsorption of antigen proteins and aluminum adjuvants, the method can be helpful for prolonging the bioavailability of the vaccine and promoting the cooperative delivery of vaccine components to lymph nodes, thereby achieving the purpose of enhancing the immune efficacy of the vaccine. In addition to aluminum adjuvants, some novel adjuvants such as CpG (negatively charged oligonucleotides, pattern recognition receptor agonist adjuvants), DOTAP (positively charged cationic liposomes) and the like also have electrostatic adsorption to protein antigens, which in turn may affect antigen-adjuvant synergistic immune efficacy. It has been reported that the adsorption degree of the antigen protein to the adjuvant can be influenced by adjusting the particle size distribution of the adjuvant or the antigen protein itself, the buffer composition, the antigen-adjuvant use ratio, the chemical coupling modification of the adjuvant or the antigen protein, and the like, thereby influencing the synergistic immunoenhancement capability of the adjuvant. However, the existing method generally has the problems of complex operation, difficulty in realizing accurate adjustment of antigen-adjuvant interaction, incapability of directionally displaying and neutralizing epitopes, insufficient immunopotentiation efficacy and the like, and severely limits the application of the existing recombinant protein vaccine. The invention aims to provide a method for enhancing the synergistic immune effect of antigen proteins and adjuvants and application thereof in the field of biological medicine, and the method is widely applicable to various antigen proteins and charged adjuvants. Disclosu