CN-121974977-A - Immunogenic peptide with function of activating anti-tumor immune response, and preparation method and application thereof

Abstract

The invention discloses a group of immunogenic peptides with an anti-tumor immune response activating function, a preparation method and application thereof, and belongs to the technical field of biological medicines. The amino acid sequences of the immunogenic peptide are SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3 and SEQ ID NO. 4, and the immunogenic peptide is obtained by extracting enterovirus-like particle (VLPs) preparations from feces of healthy mice, performing gastric lavage on tumor model mice, and separating and screening from ileum tissues of the mice by utilizing a liquid chromatography mass spectrometry combined technology. The VLPs can migrate to tumor tissues, and are presented as the immunogenic peptide through tumor cell MHC-I molecules, so that CD8 + T cells are efficiently activated, tumor immune microenvironment is remodeled, and tumor growth is inhibited. Experiments show that the immunogenic peptide alone or in combination with the PD-1 inhibitor has obvious anti-tumor effect, and the combined use tumor inhibition rate can reach 89.4 percent, which is obviously superior to single treatment.

Inventors

• FU AIKUN
• Wu Wenzi
• ZHUANG JIACHEN
• ZHAN XIUAN
• Mo Qiufen
• FU HUIMEI

Assignees

• 浙江大学

Dates

Publication Date

20260505

Application Date

20260205

Claims (10)

1. 1. A group of immunogenic peptides with the function of activating anti-tumor immune response is characterized in that the amino acid sequence is at least one of SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3 and SEQ ID NO. 4.
2. 2. The immunogenic peptide of claim 1, wherein the amino acid sequence of the immunogenic peptide is SEQ ID No. 1, SEQ ID No.2, SEQ ID No. 3, SEQ ID No. 4.
3. 3. A method of preparing an immunogenic peptide according to claim 1 or 2, comprising the steps of: S1, extracting VLPs preparation from the feces of a healthy mammal; S2, administering the VLPs formulation to a tumor-bearing animal model; s3, separating and screening the immunogenic peptide from the ileum tissues of the animals in the step S2.
4. 4. The method of claim 3, wherein step S1 comprises collecting feces from healthy mammals, homogenizing, centrifuging to obtain supernatant, filtering with a filter membrane, adding polyethylene glycol to the filtrate, incubating to form precipitate, collecting precipitate, and re-suspending to obtain VLPs preparation.
5. 5. The method of claim 4, wherein the filtration with the membrane comprises passing through a 0.45 μm membrane and a 0.22 μm membrane in sequence, and the polyethylene glycol is PEG 6000.
6. 6. The method of claim 3, wherein in step S3, MHC-peptide complexes are obtained from ileal tissue by immunoprecipitation, eluted to obtain peptide fragments, and the immunogenic peptides are screened by liquid chromatography-tandem mass spectrometry (LC-MS/MS) identification.
7. 7. A method for preparing the immunogenic peptide of claim 1 or 2, wherein the immunogenic peptide is synthesized using a solid phase peptide synthesis method or a genetic engineering expression method.
8. 8. A pharmaceutical composition comprising a therapeutically effective amount of the immunogenic peptide of claim 1 or 2 and a pharmaceutically acceptable carrier.
9. 9. The pharmaceutical composition of claim 8, further comprising a PD-1 inhibitor and/or an immunoadjuvant.
10. 10. Use of an immunogenic peptide according to claim 1 or 2 for the manufacture of a medicament for the treatment and/or prophylaxis of tumours.

Description

Immunogenic peptide with function of activating anti-tumor immune response, and preparation method and application thereof Technical Field The invention relates to the technical field of biological medicines, in particular to a group of immunogenic peptides with an anti-tumor immune response activating function, a preparation method and application thereof. Background Malignant tumor seriously threatens human health, and immune checkpoint blocking therapy represented by PD-1/PD-L1 inhibitor brings revolutionary breakthrough to tumor treatment. However, in clinical practice, a substantial proportion of patients do not respond to the therapy either primarily or secondarily, with limited efficacy. Studies have shown that one of the key causes is the lack of a sufficient number of effector CD8 + T cells in the tumor microenvironment of some patients, which specifically recognize tumor antigens, i.e. the formation of a so-called "immune desert" or "immune rejection" phenotype. In this case, even if the T cell inhibition signal is released using a PD-1/PD-L1 inhibitor, it is difficult to generate an effective anti-tumor immune response due to the lack of "soldiers" that can be activated. To increase the response rate of immunotherapy, it is often clinically attempted to combine PD-1/PD-L1 inhibitors with chemotherapy, radiation therapy or other immunotherapies. However, the traditional radiotherapy and chemotherapy has remarkable toxic and side effects, influences the life quality and tolerance of patients, has still unsatisfactory synergistic effect of the existing combined strategy, and can bring about superimposed toxic and side effects. Immunogenic peptide-based therapeutic vaccines for tumors are theoretically an ideal solution. It aims to activate and expand tumor-specific T cells by delivering specific epitopes that can be recognized by T cells, thereby providing mobilizable effector cells for immune checkpoint therapies. However, the existing peptide vaccine technology faces two key bottlenecks, namely firstly, weak immunogenicity, short peptides are easily and rapidly degraded and cleared in vivo, are difficult to be effectively captured and presented by antigen presenting cells, and cause limited strength of an induced immune response, secondly, lack of clear synergistic effect with PD-1/PD-L1 inhibitors, and currently, few reports exist on screening immunogenic peptide fragments which can not only efficiently activate CD8 + T cells, but also remarkably enhance the curative effect of the PD-1/PD-L1 inhibitors. Therefore, there is an urgent need in the art to develop novel, efficient, immunogenic peptides that can produce synergistic effects with existing immune checkpoint therapies to address the treatment of "immune desert" type tumors, improving the overall response rate and efficacy of immunotherapy. Disclosure of Invention The invention extracts enterovirus-like particle (VLPs) preparation from the feces of healthy mice, and after the preparation is infused into tumor model mice, a group of immunogenic peptides are obtained by screening from ileum tissues of the mice through a liquid chromatography mass spectrometry technology, and the amino acid sequences are SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3 and SEQ ID NO. 4. The peptide can efficiently activate CD8 + T cells, and the peptide and the PD-1 inhibitor are combined to show obvious synergistic anti-tumor effect. In one aspect, the present invention provides a group of immunogenic peptides having the function of activating an anti-tumor immune response, which adopts the following technical scheme: A group of immunogenic peptides with the function of activating anti-tumor immune response has an amino acid sequence selected from at least one of SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3 and SEQ ID NO. 4. Preferably, the amino acid sequence of the immunogenic peptide is SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3, SEQ ID NO. 4. On the other hand, the invention also provides a group of preparation methods of immunogenic peptides with the function of activating anti-tumor immune response, which adopts the following technical scheme: A method for preparing a group of immunogenic peptides with the function of activating an anti-tumor immune response, comprising the following steps: S1, extracting VLPs preparation from the feces of a healthy mammal; S2, administering the VLPs preparation to the tumor-bearing animal model; s3, separating and screening the immunogenic peptide from the ileum tissues of the animals in the step S2. Preferably, step S1 specifically comprises collecting feces of healthy mammal, homogenizing, centrifuging to obtain supernatant, filtering with a filter membrane sequentially, adding polyethylene glycol into the filtrate, incubating to form precipitate, collecting precipitate, and re-suspending to obtain VLPs preparation. Preferably, the filtration with the membrane comprises passing through 0.45 μm and 0.22 μm membrane sequentially, an