CN111375003B - Method for preparing PD-1/PD-L1 inhibitor from tangut clematis - Google Patents

Abstract

The invention discloses an active ingredient extracted from natural plant tangut clematis and an extraction method thereof, and more particularly relates to an active ingredient extracted from tangut clematis which can effectively block the combination of PD1-PDL1, thereby eliminating, inhibiting, reducing or blocking the interaction and the subsequent action of PD1-PDL1, and a pharmaceutical composition of the active ingredient and a pharmaceutically acceptable carrier can effectively become a novel PD1-PDL1 inhibitor, so that the inhibitor can be applied to the anti-tumor related diseases, and can provide reference for a clinical treatment scheme.

Description

Method for preparing PD-1/PD-L1 inhibitor from tangut clematis

The technical field is as follows:

the invention relates to the technical field of application of natural products, in particular to a pharmaceutical composition which is used for extracting active ingredients from natural plant clematis tangutica and has the functions of eliminating, inhibiting, reducing or blocking PD1-PDL1 combination and a pharmaceutically acceptable carrier of the active ingredients, and application of the pharmaceutical composition to related diseases.

Background art:

the immune system of the human body recognizes tumor cells, regulates tumor growth, and even eliminates tumors, in which T cells play a central role. Activation of T cells requires first signal stimulation by the antigen presenting cells, and second signal stimulation by the co-stimulatory molecules. The co-stimulatory molecules not only provide co-stimulatory signals for enhancing immunity, but also provide co-inhibitory signals for suppressing immunity, so as to achieve the effect of regulating immunity, and the immune inhibitory signals are immune check points. In a normal organism, an immune check point maintains immune tolerance to self-antigen on one hand and avoids autoimmune diseases caused by over-strong immune reaction, and on the other hand, negative feedback immune reaction avoids tissue damage caused by over-stimulation. However, tumor cells may abnormally up-regulate co-suppressor molecules and their associated ligands, such as PD-1, PD-L1, inhibiting the immune activity of T cells, causing tumor immune escape. Currently known immune checkpoints include: PD-1/PD-L1, CTLA-4/CD80/CD86 and TCR, LAG3, TIGIT, TIM-3, BTLA. The "immune checkpoint blockers" currently at the tip of immunotherapy have a marked effect in the treatment of many cancers, especially malignant and chemo-resistant cancers. Among them, blocking the PD-1/PD-L1 pathway is by far the most successful cancer immunotherapy strategy.

PD-1 and its ligand PD-L1 are relatively well studied immune checkpoint molecules in recent years that play an important negative regulatory role in the tumor microenvironment. PD-1 and PD-L1 combine to produce obvious inhibitory effect on T cells through mTOR and PI3K/AKT pathway. PD-1 attenuates T cell responses late in the activation process after T cells enter the tumor microenvironment. Because the adaptive immune resistance inhibits the killing effect of T cells in a tumor microenvironment on tumor cells, the blocking of the interaction of PD-1/PD-L1 can restore the immune response of an organism to tumors. The combination of PD-1 and the ligand PD-L1 can effectively reduce the immune response involved by immune T cells. The tumor cells escape immune supervision in vivo through high expression of PD-L1, and blocking the interaction of PD1 and PD-L1 can obviously improve the activity of CD8+ cytotoxic T cells so as to kill the tumor cells. PD-L1 is expressed primarily in T cells, B cells, dendritic cells, macrophages, mesenchymal stem cells and bone marrow-derived mast cells. PD-L1 is also expressed in cells of non-myeloid origin, such as vascular endothelial cells, epithelial cells, skeletal muscle cells, hepatocytes, tubular epithelial cells, islet cells, brain stellate cells and various types of non-lymphoid tumors, such as melanoma, liver cancer, gastric cancer, renal cell carcinoma, and also in cells at the site of immune privilege, such as placenta, eye. This suggests that PD-L1 has some versatility in regulating autoreactive T, B cells and immune tolerance, and plays a role in peripheral tissue T and B cell responses.

The interaction of PD-1 and PD-L1 to regulate the activation of control T cells has been largely validated in tumor and viral infections. PD-L1 is expressed on the surface of a variety of tumor cells, including: lung cancer, liver cancer, ovarian cancer, cervical cancer, skin cancer, bladder cancer, colon cancer, breast cancer, glioma, kidney cancer, stomach cancer, esophageal cancer, oral squamous cell carcinoma, head and neck cancer.

Since 2014, the first PD-1 monoclonal antibody Pembrolizumab was marketed, a total of 15 PD-1/PD-L1 antibody drugs have been approved so far, wherein 9 monoclonal antibody drugs, 3 small molecule peptide inhibitors and 3 non-small molecule peptide drugs each, and the PD-1/PD-L1 drug has become an important component in the field of tumor immunity. According to the statistics of 2018, from 9 months of 2017 to 9 months of 2018, 748 clinical trials of PD-1/PD-L1 drug clinical trials are newly developed, and 2250 clinical trials in an active state are counted. In this 2250 clinical trial, 1716 had a treatment regimen of PD-1/PD-L1 antibody drug in combination with other cancer therapies. The number of PD-1/PD-L1 drug clinical trials has increased dramatically, from sector one in 2006 to 2250 at present in 2018.

Currently, the anti-tumor response is shown to be persistent in different cancer patients against PD-1/PD-L1 antibody drugs. However, the inherent disadvantages of antibody therapy, such as high cost, poor oral administration, immune-related side effects, and a first-line total population response rate of a single drug, are only 20% -30%. Therefore, the development of non-peptide small molecule inhibitors of the PD-1/PD-L1 pathway is a promising option for treating tumor patients.

The tangut clematis can be used as a medicine, is bent sometimes, has longitudinal edges, is gray brown or tan, is hard and crisp, is easy to break, and has a flat and white section. The leaves are curled, shriveled, crushed, brownish or grayish green, the small leaves are in a shape of a long and narrow circle or a needle shape after being unfolded, the small leaves are deep-cracked, the edges of the small leaves are provided with incised sawteeth, and the back of the small leaves is fluffed. The flower is in the shape of a bud, some of the flower is flattened and orange, sepals are 4, the flower is in an oblong shape, the tip of the flower is gradually sharp, and the outer surface of the flower is soft. Distributed in northeast of Qinghai-Tibet plateau and Qinghai.

The functions and indications are as follows: dispel cold, increase stomach fire, activate blood and remove stasis, break mass and tumor. Can be used for treating stomach cold, dyspepsia, abdominal mass tumor, jaundice, cold tumor, and edema.

Disclosure of Invention

The invention discloses an active ingredient extracted from natural plant clematis tangutica and an extraction method thereof, and more particularly relates to an active ingredient extracted from the clematis tangutica, which can effectively block the combination of PD1-PDL1, thereby eliminating, inhibiting, reducing or blocking the interaction and subsequent action of PD1-PDL1, and a pharmaceutical composition of the active ingredient and a pharmaceutically acceptable carrier can effectively become a novel PD1-PDL1 inhibitor, so that the inhibitor can be applied to resisting tumor-related diseases.

In order to achieve the purpose, the technical problem solved by the invention adopts the following technical scheme: an active ingredient of clematis tangutica effective in blocking the binding of PD1-PDL1, characterized in that the active ingredient is derived from an aqueous extract fraction of clematis tangutica; furthermore, the water phase extract part of the clematis tangutica is separated by D101 macroporous absorption resin and eluted by ethanol-water systems with different proportions, and the active ingredients mainly come from 20 percent of the eluted part.

In brief, the active ingredient of clematis tangutica that effectively blocked PD1-PDL1 binding was from the 20% elution site of the aqueous extract.

The preparation method of the active ingredient for effectively blocking the combination of PD1-PDL1 by the tangut clematis comprises the following steps:

(1) extraction: selecting high-quality tangut clematis, cleaning with pure water, air drying, pulverizing, soaking in 60-80% ethanol for 4-24h, extracting twice, filtering to obtain filtrate, recovering solvent under reduced pressure, adding 60-80% ethanol into the residue, ultrasonic extracting for 2 times, each time for 1-5h, and concentrating under reduced pressure to obtain 60-80% ethanol extract; extracting with 85-98% ethanol by the same method, concentrating under reduced pressure to obtain 85-98% ethanol extract, and mixing to obtain total ethanol extract. Dissolving the total ethanol extract with water at ratio of 1:1-5, extracting with ethyl acetate at ratio of 0.5-1:1 to obtain ethyl acetate part and water phase extract part;

(2) separation: separating ethyl acetate part with silica gel column chromatography, eluting with chloroform-methanol system (pure chloroform, 50:1, 25:1, 10:1, 5:1, methanol) at different ratio to obtain 6 eluate parts; eluting the water phase extract with D101 macroporous adsorbent resin in ethanol-water system (pure water, 20%, 40%, 60%, 80%, 95%) at different ratio to obtain 6 eluates.

Wherein the reduced pressure recovery condition is 0.1-0.5MPA and the temperature is 25-40 ℃; the ultrasonic extraction condition is 200-800HZ, the ultrasonic treatment is carried out for 30-45min, and the temperature is 30-50 ℃.

Wherein, the extraction conditions are as follows: the extraction pressure is 20MPa to 40MPa, the extraction temperature is 30 ℃ to 50 ℃, and the extraction time is 0.8h to 2.5 h.

Wherein, the silica gel column chromatography separation conditions are as follows: using chloroform-methanol system as eluent, gradient eluting with pure chloroform, 50:1, 25:1, 10:1, 5:1 and methanol at flow rate of 0.2-1.0 ml/min.

Wherein, the separation conditions of the D101 macroporous adsorption resin are as follows: eluting with ethanol-water system as eluent, gradient eluting with pure water, 20%, 40%, 60%, 80%, 95%, and flow rate of 0.3-1.5 ml/min.

The invention also relates to a pharmaceutical composition containing the active ingredient of the tangut clematis tangutica and a pharmaceutically acceptable carrier.

In another aspect, the present invention provides a method for preventing or treating a disease or disorder by eliminating, inhibiting, reducing, or blocking PD1-PDL1 binding activity, comprising administering to a subject in need thereof a therapeutically effective amount of a site of an active extract of clematis tangutica of the present invention in combination with a pharmaceutically acceptable carrier.

Wherein the disease or disorder is selected from cancer; preferably, the cancer is selected from melanoma, renal cancer, prostate cancer, breast cancer, colon cancer, lung cancer, bone cancer, pancreatic cancer, skin cancer, cancer of the head or neck, cutaneous or intraocular melanoma, uterine cancer, ovarian cancer, rectal cancer, cancer of the anal region, stomach cancer, testicular cancer, uterine cancer, carcinoma of the fallopian tubes, carcinoma of the endometrium, carcinoma of the cervix, carcinoma of the vagina, carcinoma of the vulva, Hodgkin's disease, non-Hodgkin's lymphoma, carcinoma of the esophagus, cancer of the small intestine, cancer of the endocrine system, cancer of the thyroid gland, cancer of the parathyroid gland, cancer of the adrenal gland, sarcoma of soft tissue, cancer of the urethra, cancer of the penis, chronic or acute leukemia including acute myeloid leukemia, chronic myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, solid tumors of childhood, lymphocytic lymphoma, cancer of the bladder, cancer of the kidney or ureter, renal pelvis, neoplasms of the central nervous system, neoplasms of the head or neck, malignant melanoma, cancer of the head or neck, cancer of the head of the stomach, cancer of the esophagus, carcinoma of the colon of the rectum, carcinoma of the colon of the rectum, carcinoma of the colon of the rectum, carcinoma of the rectum of the lung, and the rectum of the lung of the colon of the lung of, Primary central nervous system lymphoma, tumor angiogenesis, spinal axis tumor, brain stem glioma, pituitary adenoma, kaposi's sarcoma, epidermoid carcinoma, squamous cell carcinoma, T-cell lymphoma, environmentally induced cancer, including combinations of said cancers.

The term "preventing or treating a disease or disorder by eliminating, inhibiting, reducing or blocking PD1-PDL1 binding activity" as used herein is intended to mean a disease or disorder caused by PD-1 expression or that is symptomatic/characterized by PD1-PDL1 binding. In some embodiments, the disease or disorder is selected from cancer. Such cancers include, but are not limited to, lung cancer, liver cancer, ovarian cancer, cervical cancer, skin cancer, bladder cancer, colon cancer, breast cancer, glioma, kidney cancer, gastric cancer, esophageal cancer, oral squamous cell carcinoma, head and neck cancer.

As used herein, "therapeutically effective amount" refers to a dose sufficient to show its benefit to the subject to which it is administered. The actual amount administered, as well as the rate and time course of administration, will depend on the individual condition and severity of the condition being treated. Prescription of treatment (e.g., decisions on dosage, etc.) is ultimately the responsibility of and depends on general practitioners and other physicians, often taking into account the disease being treated, the condition of the individual patient, the site of delivery, the method of administration, and other factors known to the physician.

The term "subject" as used herein refers to a mammal, such as a human, but may also be other animals, such as wild animals (e.g., herou, geranium, crane, etc.), domestic animals (e.g., ducks, geese, etc.) or laboratory animals (e.g., orangutans, monkeys, rats, mice, rabbits, guinea pigs, etc.).

The term "pharmaceutical composition" as used herein denotes a combination of at least one drug, optionally together with a pharmaceutically acceptable carrier or adjuvant, combined together to achieve a specific purpose. In embodiments, the pharmaceutical compositions include temporally and/or spatially separated combinations, so long as they are capable of acting together to achieve the objectives of the present invention. For example, the ingredients contained in the pharmaceutical composition (e.g., the pharmaceutical composition of the aqueous extract fraction of clematis tangutica according to the present invention and a pharmaceutically acceptable carrier) may be administered to the subject in whole or separately. When the ingredients contained in the pharmaceutical composition are administered separately to a subject, the ingredients may be administered to the subject simultaneously or sequentially. Preferably, the pharmaceutically acceptable carrier is water, aqueous buffered solutions, isotonic saline solutions such as PBS (phosphate buffered saline), glucose, mannitol, dextrose, lactose, starch, magnesium stearate, cellulose, magnesium carbonate, 0.3% glycerol, hyaluronic acid, ethanol, or polyalkylene glycols such as polypropylene glycol, triglycerides, and the like. The type of pharmaceutically acceptable carrier used depends inter alia on whether the composition according to the invention is formulated for oral, nasal, intradermal, subcutaneous, intramuscular or intravenous administration. The compositions according to the invention may comprise wetting agents, emulsifiers or buffer substances as additives.

The invention also provides application of the pharmaceutical composition of the active extract part of the tangut clematis and the pharmaceutically acceptable carrier in preparing medicines for treating diseases or symptoms, in particular application of antitumor medicines for treating tumor diseases, and application of the pharmaceutical composition of the active extract part of the tangut clematis and the pharmaceutically acceptable carrier in effectively eliminating, inhibiting, reducing or blocking the antitumor medicines combined by PD1-PDL 1.

The anti-tumor drug of the drug composition of the active extract part of the clematis tangutica and the pharmaceutically acceptable carrier can be an oral preparation, an injection preparation or other preparation types.

The anti-tumor medicinal preparation of the medicinal composition of the active extract part of the clematis tangutica and the medicinal carrier is prepared by combining the active extract part of the clematis tangutica and pharmaceutically acceptable medicinal auxiliary materials.

The pharmaceutic adjuvant is one or more of excipient, diluent, carrier, flavoring agent, adhesive, filler, drug carrier, solubilizer, cosolvent, emulsifier, suspending agent, clarifier, deflocculant, correctant, colorant, preservative, chemical sterilizing agent, adsorbent, filter aid, antioxidant, pH regulator, isotonic regulator, diluent, adhesive, wetting agent, disintegrant, lubricant, antioxidant, controlled release agent, coating material, film-forming material and capsule material.

The oral preparation can be tablets, capsules, granules, oral liquid solvents, liposomes and the like.

The injection preparation can be liposome injection, nano injection, microsphere injection, etc.

The preferred dosage form is an oral dosage form or an injectable dosage form. Oral dosage forms and injectable dosage forms are the most preferred routes of administration. The oral dosage form refers to a dosage form for intestinal administration, and preferably, the oral dosage form is a sustained-release or controlled-release oral preparation. Wherein the capsule dosage form comprises soft capsule or hard capsule.

In addition, the preparation of the active ingredient of the clematis tangutica for effectively eliminating, inhibiting, reducing or blocking the binding of PD1-PDL1 can also be a preparation of other administration routes: such as respiratory tract administration preparations (spray, aerosol, powder spray); dermal preparations (topical solutions, lotions, liniments, ointments, plasters, pastes, patches); film administration preparations (eye drops, nose drops, ophthalmic ointment, gargle, sublingual tablet); the preparation (suppository) is administered via cavity.

The injection can be a conventional injection preparation; preferably, the injection is a liposome injection, a nano injection or a microsphere injection, and the injections respectively adopt liposome, nano particles and microspheres as drug carriers, so that the circulation time of the drug-loaded particles in the body is prolonged, the retention time of the drug-loaded particles at an absorption part is prolonged, the burst effect of the drug at the initial release stage is controlled, and the drug effect is enhanced. Preferably, the nanoparticles used as the carrier in the nanoparticle injection are nanocrystallized colloidal particles.

By adopting the technical scheme, compared with the prior art, the invention has the beneficial effects that:

1. the extract part of the clematis tangutica active extract can effectively eliminate, inhibit, reduce or block the combination of PD1-PDL1, and can be used for preparing antitumor drugs for generating cancers due to the combination of PD1-PDL 1. Is suitable for developing antitumor drugs. The applicant found in the study that: at present, raw materials for preparing the anti-cancer medicine are deficient, and in the prior art, the traditional Chinese medicine tangut clematis has the functions of dispelling cold, proliferating stomach fire, promoting blood circulation to remove blood stasis and breaking glomus and tumor accumulation. Can be used for treating stomach cold, dyspepsia, abdominal mass tumor, jaundice, cold tumor, and edema. In the research of the application, the active ingredients of the tangut clematis have the effects of eliminating, inhibiting, reducing or blocking the binding of PD1-PDL 1. The extraction method of the active site is researched, and the active extract has the activity of eliminating, inhibiting, reducing or blocking the binding of PD1-PDL1, but the effect is not achieved in other extracted part components. The applicant has paid much creative work in the process of finding out the problems and solving the problems.

2. The method for separating and extracting the components of the clematis tangutica has the advantages of fast separation of the components of the clematis tangutica, simple and stable separation and extraction process, suitability for industrial continuous production, higher product yield, high-efficiency and simple separation of various active ingredients, separation of the active ingredients in a water phase and reduction of the influence of an organic solvent on the activity of the medicine.

3. The application of the active extract part of the tangut clematis in preparing the antitumor drug for eliminating, inhibiting, reducing or blocking the combination of PD1-PDL1 expands the combination inhibitor or raw material drug channel of PD1-PDL1, increases the providers of effective drugs, expands the medicinal value of the tangut clematis, enables the tangut clematis to be developed into a new raw material for inhibiting the combination of PD1-PDL1 with the antitumor drug, and can obviously improve the economic value and the use value of the tangut clematis.

Description of the drawings:

FIG. 1 shows the performance test of each extracted part of clematis tangutica;

FIG. 2 shows IFN γ detection, an experiment of T cell function stimulated in vitro by various extracts of Clematis tangutica;

FIG. 3 shows the in vitro T cell function stimulation assay of various extracts of Clematis tangutica, IL2 assay;

FIG. 4 shows that each extract of Clematis tangutica stimulates T cells to kill tumor cells in vitro.

The specific implementation mode is as follows:

the technical solutions in the embodiments of the present invention are clearly and completely described below with reference to specific embodiments. It should be understood that the described embodiments are part of the present invention, and are intended to be illustrative only and not limiting in scope. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

Example 1 preparation of crude extract of active fraction of Clematis tangutica

The preparation method of the active ingredient for effectively blocking the combination of PD1-PDL1 by the tangut clematis comprises the following steps:

(1) extraction: selecting high-quality tangut clematis, cleaning with pure water, air drying, pulverizing, soaking in 60% ethanol for 8h, extracting twice, filtering to obtain filtrate, recovering solvent under reduced pressure, adding 70% ethanol into the residue, ultrasonic extracting for 2 times, each time for 3h, and concentrating under reduced pressure to obtain 70% ethanol extract; extracting with 83% ethanol once, concentrating under reduced pressure to obtain 83% ethanol extract, and mixing to obtain total ethanol extract. Dissolving the total ethanol extract with water at ratio of 1:3, extracting with ethyl acetate at ratio of 0.4:1 to obtain ethyl acetate part and water phase extract part;

(2) separation: separating ethyl acetate part with silica gel column chromatography, eluting with chloroform-methanol system (pure chloroform, 50:1, 25:1, 10:1, 5:1, methanol) at different ratio to obtain 6 eluate parts; eluting the water phase extract with D101 macroporous adsorbent resin in ethanol-water system (pure water, 20%, 40%, 60%, 80%, 95%) at different ratio to obtain 6 eluates. Wherein the pure water elution part and the ethyl acetate 50:1 elution part in the water phase extract are active parts of the tangut clematis which can effectively block the combination of PD1-PDL 1.

Wherein the reduced pressure recovery condition is 0.28MPA and the temperature is 28 ℃; the ultrasonic extraction conditions are 550HZ, 30min of ultrasonic treatment and 30 ℃.

Wherein, the extraction conditions are as follows: the extraction pressure is 28MPa, the extraction temperature is 36 ℃, and the extraction time is 2 h.

Wherein, the silica gel column chromatography separation conditions are as follows: using chloroform-methanol system as eluent, gradient eluting with pure chloroform, 50:1, 25:1, 10:1, 5:1 and methanol at flow rate of 0.5 ml/min.

Wherein, the separation conditions of the D101 macroporous adsorption resin are as follows: eluting with ethanol-water system as eluent, gradient eluting with pure water, 20%, 40%, 60%, 80%, 95%, and flow rate of 0.8 ml/min.

Example 2 preparation of crude extract of active fraction of Clematis tangutica

The preparation method of the active ingredient for effectively blocking the combination of PD1-PDL1 by the tangut clematis comprises the following steps:

(1) extraction: selecting high-quality tangut clematis, cleaning with pure water, air drying, pulverizing, soaking in 74% ethanol for 4h, extracting twice, filtering to obtain filtrate, recovering solvent under reduced pressure, adding 80% ethanol into the residue, ultrasonic extracting for 2 times, each time for 4h, and concentrating under reduced pressure to obtain 80% ethanol extract; extracting with 85% ethanol once, concentrating under reduced pressure to obtain 85% ethanol extract, and mixing to obtain total ethanol extract. Dissolving the total ethanol extract with water at ratio of 1:4, extracting with ethyl acetate at ratio of 0.5:1 to obtain ethyl acetate part and water phase extract part;

(2) separation: separating ethyl acetate part with silica gel column chromatography, eluting with chloroform-methanol system (pure chloroform, 50:1, 25:1, 10:1, 5:1, methanol) at different ratio to obtain 6 eluate parts; eluting the water phase extract with D101 macroporous adsorbent resin in ethanol-water system (pure water, 20%, 40%, 60%, 80%, 95%) at different ratio to obtain 6 eluates. Wherein the pure water elution part and the ethyl acetate 50:1 elution part in the water phase extract are active parts of the tangut clematis which can effectively block the combination of PD1-PDL 1.

Wherein the reduced pressure recovery condition is 0.35MPA and the temperature is 30 ℃; the ultrasonic extraction conditions are 300HZ, 35min of ultrasonic treatment and 35 ℃.

Wherein, the extraction conditions are as follows: the extraction pressure is 30MPa, the extraction temperature is 40 ℃, and the extraction time is 1 h.

Wherein, the silica gel column chromatography separation conditions are as follows: using chloroform-methanol system as eluent, gradient eluting with pure chloroform, 50:1, 25:1, 10:1, 5:1 and methanol at flow rate of 0.8 ml/min.

Wherein, the separation conditions of the D101 macroporous adsorption resin are as follows: eluting with ethanol-water system as eluent, gradient eluting with pure water, 20%, 40%, 60%, 80%, 95%, and flow rate of 1.0 ml/min.

Example 3 detection of the Performance of Clematis tangutica for blocking PD1-PDL1 binding active site

The following experiment was conducted using the active site of clematis tangutica extracted and purified in examples 1 and 2 as a drug property detector:

wherein HTRF PD1/PDL1 detection kit (purchased from CISBO), HTRF PD1/PDL1 detection kit detection principle are used in the experiment: the HTRF PD1/PDL1 detection kit detects the interaction between PD1 and PDL1 protein. The characterization of each compound and antibody blocker can be performed rapidly, simply, and in high throughput using HTRF (homogeneous time-resolved fluorescence) technology. The interaction between Tag1-PD-L1 and Tag2-PD1 was examined by using anti-Tag 1-europium (HTRF donor) and anti-Tag2-XL665 (HTRF acceptor). When the donor and acceptor antibodies are brought into proximity due to the binding of PD-L1 and PD1, excitation of the donor antibody triggers the transfer of Fluorescence Resonance Energy (FRET) to the acceptor antibody, which releases a specific signal at 665 nm. This specific signal is proportional to the degree of interaction of PD 1/PD-L1. Thus, a compound or antibody that blocks the PD1/PD-L1 interaction will result in a reduction in HTRF signal.

Experimental design screening method (kit experimental method): extracting appropriate amount of each part of the Tangut clematis, and dissolving with DMSO respectively for use. The experiment was divided into 3 groups, one for each experiment (2. mu.L of extract), one for each positive control (2. mu.L of kit solvent, positive) and one for each negative control (2. mu.L of DMSO, negative), each set of three duplicate wells.

Experimental groups: transferring 2 mu L of ethanol-water extract and ethyl acetate into a 96-well plate, sequentially adding 4 mu LTag1-PD-L1protein (kit) and 4 mu LTag2-PD-1protein (kit), standing at room temperature for 15min, adding 10 mu L of prepared solution (kit pre-mixed anti-Tag-1-Eu 3+ and anti-Tag 2-XL), and standing at room temperature for 2 h.

Positive control group: mu.L of kit solvent, dilent, 4. mu.L of Tag1-PD-L1protein and 4. mu.L of Tag2-PD-1protein were transferred and added to a 96-well plate, and left at room temperature for 15min, then 10. mu.L of the solution prepared in advance (kit pre-mixed anti-Tag1-Eu3+ and anti-Tag2-XL665) was added and left at room temperature for 2 h.

Negative control group: transferring 2 mu L of DMSO and 4 mu L of Tag1-PD-L1protein into a 96-well plate, and standing at room temperature for 15 min; then 10. mu.L of the solution prepared in advance (kit pre-mixed anti-Tag1-Eu3+ and anti-Tag2-XL665) is added and placed for 2h at room temperature. The values of Signal 665nm and Signal 620nm were measured with a microplate reader. Is calculated according to the following formula

The analysis of the results shows that the ratio of each active site is processed, wherein the ratio is less than 0, and the representative site has the active components, which can block the binding interaction of PD1-PDL1, block the signal path of PD1-PDL1, and prevent the development of diseases.

As shown in figure 1, the parts 1-6 are sequentially active parts obtained by eluting the water phase extract part with pure water, 20%, 40%, 60%, 80% and 95% ethanol in an elution system, the parts 7-12 are parts obtained by eluting the ethyl acetate part with pure chloroform, 50:1, 25:1, 10:1, 5:1 and methanol in a chloroform-methanol system, and the parts are collected, and the influence of each part on the binding interaction of PD1-PDL1 is detected by using an HTRF PD1/PDL1 detection kit.

As can be seen from fig. 1, in each of the ethyl acetate extraction site and the aqueous phase extract site of tangut clematis, 20% of the elution sites of the aqueous phase extract were shown to have the effect of eliminating, inhibiting, reducing or blocking the PD1-PDL1 binding interaction, so that the extract of 20% of the elution sites of the aqueous phase extract of tangut clematis was an active site that effectively eliminates, inhibits, reduces or blocks the PD1-PDL1 binding interaction, and this active ingredient could develop an antitumor inhibitor by blocking the PD1-PDL1 binding interaction.

Example 4 in vitro stimulation of T cell function by active extract of Clematis tangutica-tetanus toxin stimulation assay

Freshly prepared PBMCs were plated into 96-well flat-bottom plates and after overnight incubation concentrations (100ug/ml) of aqueous extract of Clematis tangutica, ethyl acetate extract and 100ng/ml Tetanus Toxoid (TT) (List Biological Laboratories) were added. The supernatant was harvested three days later, and the IFN γ content in the supernatant was detected by Elisa using IFN γ kit from R & D System, wherein Atezolizumab was used as a positive control group. As can be seen from the results in FIG. 2, 20% of the water-phase extract of clematis tangutica eluted part of the extract greatly increased the cytokine secreted by the immune cells stimulated and activated by tetanus toxin TT after eliminating, inhibiting, reducing or blocking PD1-PDL1 signal, while the other parts had insignificant effects.

Example 5 in vitro stimulation of T cell function by active extract of Clematis tangutica

Freshly prepared PBMC (obtained according to the conventional preparation method) were plated on 96-well flat-bottom plates, incubated overnight, added with 100ug/ml concentration of aqueous extract of clematis tangutica, ethyl acetate extract and 100ng/ml of Tetanus Toxoid (TT), and after 3 days of culture, the supernatant was collected and the secretion levels of aqueous extract of clematis tangutica, ethyl acetate extract and positive control (Atezolizumab) IL2 were measured using the Luminex instrument of Life Technology and the CD8+ cytokine detection kit of EMD. As can be seen from the results in FIG. 3, 20% of the water-phase extract in clematis tangutica has greatly increased cytokine IL2 secreted by the stimulated immune cells after eliminating, inhibiting, reducing or blocking PD1-PDL1 signals, and can stimulate the functions of T cells, while the other parts have insignificant effects.

Example 6 active extract of Clematis tangutica stimulates T cells to kill tumor cells in vitro

HCT116 cells were infected with lentivirus (Qiagen) expressing PD-L1protein to obtain HCT116 cell line stably expressing PD-L1, and then GFP gene was introduced to stably express GFP protein. Dendritic Cells (DC) were extracted from human fresh peripheral blood cells, and after co-culturing with the above-mentioned modified HCT116 cells (300 cells/well) at 300 cells/well for 3 days in a 96-well plate, the extracted T cells (1000 cells/well) and 100ug/ml of an aqueous extract of clematis tangutica, an ethyl acetate extract and a positive control (Atezolizumab) were added, and co-culturing was carried out for 3 days, and GFP fluorescence was read. The results (see fig. 4) show that the effect of killing tumor cells by extrasomatic stimulation T cells extracted from 20% of elution parts in the tangut clematis is remarkable, and the effect of killing tumor cells from other parts is not obvious.

Example 7 anti-tumor inhibitor tablet that blocks the binding of PD1-PDL1

The preparation method of the troche of the active site of the tangut clematis comprises the following steps: 480mg of the active extraction part of the tangut clematis and 160mg of starch are mixed evenly, 76.8mg of starch paste with the mass percent of 12% is added to prepare soft materials, wet granules are obtained by sieving, dry granules are obtained by drying, 10mg of magnesium stearate is added to be mixed evenly, and tabletting is carried out, thus obtaining the anti-tumor inhibitor for blocking the combination of PD1-PDL 1.

Example 8 anti-tumor inhibitor pellet capsules blocking PD1-PDL1 binding

The pellet capsule consists of the following raw materials in percentage by weight:

400mg of the active extraction part of the tangut clematis;

80mg of lecithin;

50mg of taurocholate sodium;

45mg of microcrystalline cellulose;

the preparation method comprises the following steps: mixing the active extract part of the tangut clematis, lecithin, sodium taurocholate and microcrystalline cellulose uniformly according to a ratio, adding an ethanol water solution, uniformly stirring to obtain a pasty material, pouring the pasty material into an extruder, extruding, obtaining granules by a roller, obtaining pellets by an extrusion speed of 380rpm/min, a roller speed of 900r/min and a roller time of 30min, drying, obtaining pellets by a 24-35 mesh sieve, and filling the pellets into a capsule shell to obtain the antitumor inhibitor pellet capsule for blocking the combination of PD1-PDL 1.

Example 9 antitumor inhibitor liposomes that block PD1-PDL1 binding

An antitumor inhibitor liposome for blocking PD1-PDL1 combination comprises an antioxidant, an active site of clematis tangutica, phospholipid, a cholesterol compound, a surfactant and an aqueous medium, wherein the mass ratio of the active site of clematis tangutica to the antioxidant, the phospholipid, the cholesterol and the surfactant is 1:3-50:5-100:1-50:0-200, preferably, the mass ratio of the active site of clematis tangutica, the phospholipid, the cholesterol and the surfactant is 1:3-30:5-50:1-30:0-100, and further preferably 1:4-20:5-25:1-10: 50-100.

Wherein the phospholipid may be a natural phospholipid such as: one or more of soybean lecithin, yolk lecithin and hydrogenated soybean lecithin; synthetic phospholipids such as: dioleoylphosphatidylcholine (DOPC), Dipalmitoylphosphatidylcholine (DPPC), phosphatidylserine (DOPS), Distearoylphosphatidylethanolamine (DSPE), Dioleoylphosphatidylethanolamine (DOPE), Dipalmitoylphosphatidylglycerol (DPPG), (2, 3-dioleoyl-propyl) -trimethylamine (DOTAP), and the like; optionally, phospholipid with functional modification such as PEG-DSPE can be added into phospholipid.

The surfactant can be Tween 80, Span 20, sodium cholate or the like.

The aqueous phase medium is a subacid PBS buffer solution, preferably, the pH value of the PBS buffer solution is 3-6, and further preferably, the pH value of the PBS buffer solution is 4.5-6.0.

The co-carried liposome can be prepared by an injection method or a thin film hydration method, and the preparation method comprises the following specific steps:

1. injection method

a. Dissolving phospholipid, cholesterol and surfactant in organic reagent at a certain ratio to obtain organic phase, wherein the organic reagent can be one or more of ethanol, chloroform, etc.;

b. dissolving the active site of the glaucous tangutica in a water phase medium to prepare a solution of the active site of the glaucous tangutica;

c. b, adding the solution of the active site of the clematis tangutica into the organic phase in the step a, performing ultrasonic treatment to form a uniform emulsion phase, and performing rotary evaporation to remove the organic solvent to obtain a liposome solution;

d. filtering the liposome solution with microporous filter membranes of 0.8 μm, 0.45 μm, 0.22 μm and 0.1 μm to obtain stable co-carried liposome.

2. Thin film hydration process

a. Dissolving phospholipid, cholesterol and surfactant in an organic reagent according to a certain ratio to prepare an organic phase, and removing the organic reagent by spinning to obtain a uniform lipid membrane, wherein the organic reagent can be one or a mixture of ethanol, chloroform and the like;

b. dissolving the active site of the glaucous tangutica in a water phase medium to prepare a solution of the active site of the glaucous tangutica;

c. b, adding the solution of the active site of the clematis tangutica into the lipid membrane obtained in the step a, and hydrating at room temperature to obtain a liposome solution;

d. reducing the particle size of the liposome by ultrasonic treatment, and sequentially filtering with microporous filter membranes of 0.8 μm, 0.45 μm, 0.22 μm and 0.1 μm to obtain stable liposome solution.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (7)

1. An active ingredient of clematis tangutica effective in blocking the binding of PD1-PDL1, characterized in that the active ingredient is derived from an aqueous extract fraction of clematis tangutica;

separating the water phase extract part of herba Clematidis tangutici with D101 macroporous adsorbent resin, eluting with ethanol-water system of different proportions, and collecting 20% active components from the eluted part;

the preparation method of the active ingredient for effectively blocking the combination of PD1-PDL1 by the tangut clematis comprises the following steps:

(1) extraction: selecting high-quality tangut clematis, cleaning with pure water, air drying, pulverizing, soaking in 60-80% ethanol for 4-24h, extracting twice, filtering to obtain filtrate, recovering solvent under reduced pressure, adding 60-80% ethanol into the residue, ultrasonic extracting for 2 times, each time for 1-5h, and concentrating under reduced pressure to obtain 60-80% ethanol extract; extracting with 85-98% ethanol by the same method, concentrating under reduced pressure to obtain 85-98% ethanol extract, and mixing to obtain total ethanol extract; dissolving the total ethanol extract with water at ratio of 1:1-5, extracting with ethyl acetate at ratio of 0.5-1:1 to obtain ethyl acetate part and water phase extract part;

(2) separation: separating ethyl acetate part with silica gel column chromatography, eluting with chloroform-methanol system (pure chloroform, 50:1, 25:1, 10:1, 5:1, methanol) at different ratio to obtain 6 eluate parts; eluting the water phase extract with D101 macroporous adsorbent resin in ethanol-water system (pure water, 20%, 40%, 60%, 80%, 95%) at different ratio to obtain 6 eluates.

2. An anti-tumor pharmaceutical composition effective to eliminate, inhibit, reduce or block the binding of PD1-PDL1, characterized by: an active ingredient comprising the clematis tangutica of claim 1 that effectively blocks PD1-PDL1 binding and a pharmaceutically acceptable carrier.

3. Use of a pharmaceutical composition according to claim 2 for the manufacture of a medicament, wherein: the application of the compound in the preparation of antitumor drugs for effectively eliminating, inhibiting, reducing or blocking the combination of PD1-PDL 1.

4. Use of a pharmaceutical composition according to claim 3 for the preparation of a medicament, characterized in that: the tumor is selected from melanoma, renal cancer, prostate cancer, breast cancer, colon cancer, lung cancer, bone cancer, pancreatic cancer, ovarian cancer, rectal cancer, cancer of the anal region, gastric cancer, testicular cancer, fallopian tube cancer, endometrial cancer, cervical cancer, vaginal cancer, vulvar cancer, hodgkin's disease, non-hodgkin's lymphoma, esophageal cancer, small intestine cancer, thyroid cancer, parathyroid cancer, adrenal cancer, soft tissue sarcoma, urethral cancer, penile cancer, chronic or acute leukemia, and combinations of tumors thereof;

the tumor is a disease or disorder characterized by PD-1 expression or by a decrease in immunotherapy resulting from binding of PD1-PDL 1.

5. The pharmaceutical composition of claim 2, wherein: the pharmaceutical composition is an oral preparation or an injection preparation.

6. The pharmaceutical composition of claim 5, wherein: the oral preparation is tablet, capsule, granule, oral liquid, or liposome.

7. The pharmaceutical composition of claim 2, wherein: the pharmaceutically acceptable carrier is water, buffered aqueous solution, isotonic saline solution, glucose, mannitol, dextrose, lactose, starch, magnesium stearate, cellulose, magnesium carbonate, 0.3% glycerol, hyaluronic acid, ethanol, or polyalkylene glycol.

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