Application of engineered extracellular vesicles targeting interleukin 6 in preparation of acute pancreatitis treatment drugs

Abstract

The invention discloses an application of engineered extracellular vesicles targeting IL-6 (interleukin-6) in preparation of a medicine for treating acute pancreatitis. According to the application, an acute pancreatitis model is constructed through intraperitoneal injection of leifrotin and LPS or arginine on C57BL / 6 mice, and after treatment by injection of engineered extracellular vesicles IL6ST-EN144-EVs, serum amylase and lipase levels, IL-6 level, pancreatic tissue pathological score and death rate of the mice are all lower than those of a control group, and pathological changes of acute pancreatitis are obviously improved. The engineered extracellular vesicles IL6ST-EN144-EVs are applicable to preparation of drugs for treating acute pancreatitis, so that targeted treatment of acute pancreatitis inflammation is realized, inflammatory response is remarkably reduced, pancreatic injury is relieved, and the engineered extracellular vesicles IL6ST-EN144-EVs have a good treatment effect.

Description

Technical Field

[0001] The present invention belongs to the field of biomedicine and relates to the application of an engineered extracellular vesicle targeting interleukin-6 in the preparation of a therapeutic drug for acute pancreatitis. Background Art

[0002] Acute Pancreatitis (AP) is an acute inflammatory injury of pancreatic tissue caused by various etiologies and is one of the main gastrointestinal diseases leading to hospitalization of patients worldwide, and its incidence is increasing year by year. According to the severity of the condition, acute pancreatitis can be divided into Mild Acute Pancreatitis (MAP) and Severe Acute Pancreatitis (SAP). SAP is accompanied by transient or persistent organ failure, and the fatality rate is extremely high if combined with infection. The common etiologies of acute pancreatitis are related to various factors such as biliary tract diseases, hyperlipidemia, and long-term heavy alcohol intake. Its pathogenesis is complex and involves abnormal expression of various inflammatory factors and cell damage, including abnormal activation of trypsinogen, overactivation of leukocytes, inflammatory factors, oxidative stress response, intestinal bacterial translocation, and pancreatic microcirculation disorders.

[0003] During the occurrence and development of AP, pancreatic acinar cells are first damaged, releasing a variety of inflammatory mediators, such as cytokines and interleukins, which are produced in large quantities, triggering a local inflammatory response and forming a so-called "cytokine storm" through cascade immune activation, thereby affecting the functions of multiple organs and systems throughout the body. Interleukin-6 (IL-6) is one of the most important cytokines in AP, starting from cell damage and lasting until systemic inflammatory response and involvement of distant organs. The high expression of IL-6 is closely related to the severity of the disease, and many studies have verified that the serum level of IL-6 within the first 48 hours can be used as a reliable marker for the severity of AP and multiple organ dysfunction.

[0004] Depending on its different transmembrane signaling forms, IL-6 plays different roles in inflammation. Its signaling pathways are mainly divided into the classical signaling pathway and the trans-signaling pathway. In the classical signaling pathway, IL-6 binds to its receptor IL-6R, and then binds to the β subunit of the IL-6 receptor, glycoprotein 130 (IL6ST), initiating intracellular inflammatory signal transduction. In the trans-signaling pathway, IL-6 binds to the soluble IL-6 receptor (sIL-6R). After forming a complex, it binds to IL6ST on the cell membrane, thereby triggering intracellular inflammation-related signal transduction. This signal transduction method plays an important role in the transmission of distant inflammatory responses and the activation and persistence of systemic inflammatory immunity, and is also one of the important promoting factors in the occurrence and development of SAP. IL6ST is a core component of IL-6 signal transduction. It binds to the hexameric complex formed by IL-6 and IL-6R, activates downstream inflammatory pathways such as JAK / STAT, promotes the extensive activation and proliferation of inflammatory cells, and further exacerbates the systemic inflammatory response, playing an important immune amplification role in the "inflammatory storm" of SAP.

[0005] As a new way of intercellular communication, extracellular vesicles can carry proteins, lipids, nucleic acids, etc. to play bioactive roles and play a crucial role in the evolution and outcome of many diseases. In SAP, extracellular vesicles can be released by pancreatic acinar cells, causing systemic inflammatory responses. In addition, extracellular vesicles also show great potential in the treatment of lung-related diseases, sepsis, neurological diseases, etc. Extracellular vesicles have good biocompatibility and low immunogenicity, and can penetrate biological barriers to achieve precise delivery to target tissues.

[0006] Given the key role of IL6ST in IL-6 signal transduction and inflammatory activation and the effect of specific binding, using IL6ST to neutralize IL-6 to reduce the excessive inflammation and organ damage in SAP is a feasible solution. Summary of the Invention

[0007] The present invention provides an application of an engineered extracellular vesicle targeting IL-6 in the preparation of a therapeutic drug for acute pancreatitis. The extracellular vesicle expresses IL6ST on its outer surface, which can specifically neutralize free IL-6 to inhibit the activation and transmission of IL-6 and downstream signaling pathways during the onset of SAP, reduce the inflammatory storm, and thus treat SAP.

[0008] The engineered extracellular vesicle targeting IL-6 of the present invention is an extracellular vesicle IL6ST-EN144-EVs that is secreted after plasmid transfection of Expi293F cells with a fusion gene containing the β subunit of the IL-6 receptor (IL6ST) and the truncated extracellular vesicle scaffold protein EN144, and expresses IL6ST on the surface, which has been fully disclosed in Chinese Patent Application CN202310429909.8.

[0009] The amino acid sequence of the extracellular vesicle scaffold protein truncation EN144 described in the present invention is shown in SEQ ID No.1.

[0010] In the fusion gene of IL6ST and the extracellular vesicle scaffold protein truncation EN144 described in the present invention, the IL6ST gene is fused to the C-terminus of the EN144 gene. In the specific embodiment of the present invention, the nucleotide sequence of the fusion gene used is shown in SEQ ID No.2.

[0011] The engineered extracellular vesicles targeting IL-6 described in the present invention are constructed by the following steps:

[0012] (1) Construct a plasmid containing the fusion gene of IL6ST and the extracellular vesicle scaffold protein truncation EN144;

[0013] (2) Transfect the plasmid in step (1) into Expi293F cells to express IL6ST on the surface of the secreted extracellular vesicles, culture the cells, and centrifuge to collect the extracellular vesicles IL6ST-EN144-EVs.

[0014] The administration method of the acute pancreatitis treatment drug described in the present invention is intravenous injection or intraperitoneal injection, preferably intraperitoneal injection.

[0015] The present invention also provides a pharmaceutical composition, which comprises the above-mentioned engineered extracellular vesicles targeting IL-6 and a pharmaceutically acceptable carrier.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] (1) Targeted therapy with remarkable efficacy: By constructing engineered extracellular vesicles targeting IL-6, targeted inflammatory inhibition therapy for acute pancreatitis is achieved. Experimental results show that the engineered extracellular vesicles can significantly reduce the levels of serum amylase, lipase, and IL-6 in the acute pancreatitis mouse model, alleviate pancreatic tissue damage, effectively reduce the mortality rate, and the therapeutic effect is significantly better than that of the traditional IL-6 receptor antibody drug tocilizumab.

[0018] (2) Good biocompatibility and high safety: Using extracellular vesicles secreted by Expi293F cells as a drug carrier has good biocompatibility and low immunogenicity, can effectively avoid the occurrence of immune reactions, significantly improve the stability and safety of the drug in vivo, and reduce the side effects of treatment.

[0019] (3) The preparation method is simple and easy to scale up production: By transfecting Expi293F cells with the IL6ST-EN144 fusion plasmid, the extracellular vesicles secreted by Expi293F cells contain IL6ST targeting IL-6 on their surface. Without complex in vitro modification or ligation steps, the preparation method is simple, efficient, easy to scale up production, and has good prospects for industrial application.

[0020] (4) There are various administration methods and flexible applications: By comparing the curative effects of different administration methods (intraperitoneal injection and tail vein injection), the optimal administration route was determined, providing more choices and conveniences for clinical applications.

[0021] (5) The evaluation system is perfect and highly scientific: Through the comprehensive evaluation of multiple observation indicators (serum amylase, lipase, IL-6 level, pancreatic tissue pathology score, and mouse mortality), the treatment effect was comprehensively and objectively reflected, providing a scientific and reliable basis for clinical applications. Description of the Drawings

[0022] Figure 1 Are the electron microscopy image (A.), particle size distribution diagram (B.), and protein electrophoresis diagram (C.) of extracellular vesicle IL6ST-EN144-EVs.

[0023] Figure 2 Are the schematic diagrams of the construction and treatment process of the caerulein combined with LPS-induced acute pancreatitis model (A.) and the arginine-induced acute pancreatitis model (B.).

[0024] Figure 3 Are the serum amylase level (A.), lipase level (B.), IL-6 level (C.), pancreatic tissue pathology score (D.), and HE staining of pancreatic tissue (E.) of caerulein-induced acute pancreatitis mice after treatment with extracellular vesicle IL6ST-EN144-EVs.

[0025] Figure 4 Are the serum amylase level (A.), lipase level (B.), IL-6 level (C.), pancreatic tissue pathology score (D.), HE staining of pancreatic tissue (E.), and 7-day survival rate (F.) of arginine-induced acute pancreatitis mice after treatment with extracellular vesicle IL6ST-EN144-EVs. Detailed Embodiments

[0026] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be elaborated in detail below through the preferred embodiments of the present invention. However, the following embodiments do not limit the protection scope of the present invention.

[0027] In the embodiments of the present invention, those not described in detail are carried out by using conventional experimental methods in the art or according to the product specifications.

[0028] In the embodiments of the present invention, the Expi293F cell line and cell culture reagents such as high-glucose medium, serum, and trypsin were purchased from Thermo Fisher Scientific Co., Ltd., arginine was purchased from Shanghai Sangon Biotech Co., Ltd., caerulein was purchased from Beijing Solarbio Science & Technology Co., Ltd., tocilizumab was purchased from Roche Pharmaceuticals Shanghai Co., Ltd., the α-amylase detection kit was purchased from ZhongSheng Beikong Biotechnology Co., Ltd., the lipase detection kit was purchased from Nanjing Jiancheng Bioengineering Institute, the IL-6 ELISA kit was purchased from Shanghai Beyotime Biotechnology Co., Ltd., and other raw materials can be obtained from public commercial channels without special instructions.

[0029] C57BL / 6 mice were purchased from Jiangsu Jicui Yakang Biotechnology Co., Ltd. The conditions were as follows: all experimental mice were female C57BL / 6 mice at 6 - 8 weeks old. The mice were housed in an environment with a temperature of 22 ± 2°C and a humidity of 50 ± 10%, and a 12-hour light-dark cycle was adopted. Tap water and standard feed were provided for free intake. The mice were allowed to acclimatize to the environment for at least 3 days before the experiment to reduce the influence of stress factors on the experimental results. All experiments were approved by the Animal Ethics Committee of Eastern Theater General Hospital (approval number: DZWYXKT4211100928), and the experimental operations complied with the animal experiment operation specifications stipulated by the Animal Ethics Committee of Eastern Theater General Hospital.

[0030] The extracellular vesicle IL6ST-EN144-EVs described in the present invention has been fully disclosed in Chinese Patent Application CN202310429909.8, and the preparation was carried out with reference to this patent.

[0031] Example 1

[0032] Preparation of extracellular vesicle IL6ST-EN144-EVs:

[0033] 1. Construction of fusion plasmid

[0034] The murine mIL6ST gene was fused with the C-terminus of the EN144 gene to construct the mIL6ST-EN144 fusion gene (SEQ ID No.2), and then the fusion gene was inserted into the plasmid to obtain a plasmid containing the mIL6ST-EN144 fusion gene, named the IL6ST-EN144 plasmid.

[0035] 2. Plasmid transfection of Expi293F cells

[0036] (1) In a 125 ml shake flask, 8*10 6 Expi293F cells were inoculated and 20 ml of medium was added for culture.

[0037] (2) Dilute 60 μl of PEI40000 and 20 μg of IL6ST-EN144 plasmid separately and then mix them, and let it stand for 15 minutes.

[0038] (3) Drop the above plasmid evenly into the shake flask in step (1) by dropping while shaking, transfect Expi293F cells, and place them in a sterile incubator in a 37 °C, 5% CO2 shaker for 48 hours.

[0039] 3. Isolation and identification of extracellular vesicles

[0040] (1) Take the supernatant of transfected Expi293F cells, centrifuge at 500 g for 10 minutes at 4 °C to remove cell precipitate.

[0041] (2) Collect the supernatant, centrifuge at 3000 g for 20 minutes at 4 °C to remove cell debris.

[0042] (3) Collect the supernatant, centrifuge at 10000 g for 30 minutes at 4 °C to remove apoptotic bodies, collect the supernatant and filter it through a 0.22 μm filter membrane.

[0043] (4) Centrifuge the filtered supernatant at 130000 g for 70 minutes at 4 °C, discard the supernatant. Resuspend the white precipitate at the bottom with PBS, centrifuge again at 130000 g for 70 minutes at 4 °C, discard the supernatant, and resuspend with 500 μl of PBS to obtain extracellular vesicles IL6ST-EN144-EVs.

[0044] Observe the morphology of extracellular vesicles by transmission electron microscopy, detect the expression of IL6ST by protein electrophoresis, and confirm the particle size distribution and markers of extracellular vesicles by Nanoparticle Tracking Analysis (NTA) and Western Blot. The results are as Figure 1 shown.

[0045] Example 2

[0046] Therapeutic effect of extracellular vesicles IL6ST-EN144-EVs on cerulein combined with lipopolysaccharide (LPS)-induced acute pancreatitis

[0047] 1. Mouse preparation

[0048] Before the experiment, the experimental mice were divided into cages and groups, and a natural control group (NC), a pancreatitis control group (SAP), an engineered extracellular vesicle intraperitoneal injection treatment group (EVs(i.p.)), an engineered extracellular vesicle intravenous injection treatment group (EVs(i.v.)), and a tocilizumab treatment group (TOC) were set up. The mice in each group were fasted but allowed to drink water for 8 hours, labeled and weighed before modeling, and the records were made.

[0049] 2. Preparation of experimental reagents

[0050] (1) Preparation of caerulein solution: Dissolve caerulein powder with sterile PBS, prepare the caerulein stock solution (300 mg / ml) aseptically in a laminar flow hood, dispense it into sterile EP tubes, and store it at -20 °C; take an appropriate amount of the caerulein stock solution before modeling and dilute it with sterile PBS to the caerulein working solution (30 mg / ml).

[0051] (2) Preparation of LPS solution: Dissolve LPS powder with sterile PBS, prepare the LPS working solution (1 mg / ml) aseptically in a laminar flow hood, dispense it into 200 ml sterile EP tubes, and store it at -20 °C; take an appropriate amount of the LPS working solution before modeling.

[0052] 3. Construction of the caerulein combined with LPS acute pancreatitis model

[0053] Inject 7 doses of caerulein (300 μg / kg) and 1 dose of LPS (5 μg / kg) into C57BL / 6 mice by intraperitoneal injection at 1-hour intervals to construct a caerulein combined with LPS-induced acute pancreatitis model. The mice in the NC group were intraperitoneally injected with an equal volume of sterile PBS.

[0054] 4. Treatment with engineered extracellular vesicles

[0055] At 30 minutes after the establishment of the acute pancreatitis model, the EVs(i.p) group and the EVs(i.v) group were respectively treated with 1*10 10 particle numbers of extracellular vesicle IL6ST-EN44-EVs by intraperitoneal injection and tail vein injection. The mice in the NC group were intraperitoneally injected with the same volume of sterile PBS, and the mice in the TOC group were intraperitoneally injected with 5 mg / kg tocilizumab for treatment.

[0056] 5. Observation indicators

[0057] At 12 hours after the establishment of the pancreatitis mouse model and the corresponding treatment, blood was collected from the tail vein, serum was separated and retained, and the levels of serum amylase, lipase, and IL-6 were measured. At 72 hours after modeling, the mice in each group were euthanized, the pancreatic tissues were collected for HE staining of pancreatic tissue sections, and the histopathological changes were observed and the pathological scores were performed. The pathological scores were carried out according to the criteria in Table 1.

[0058] Table 1: Pathological Scoring Criteria for Acute Pancreatitis

[0059]

[0060]

[0061] 6. Experimental Results

[0062] As Figure 3 shown, compared with the NC group, the levels of serum amylase, lipase, and IL-6 in the SAP group of mice were significantly increased (p < 0.05). HE staining of pancreatic tissue showed obvious inflammatory cell infiltration, edema, and acinar cell necrosis, and the HE score was significantly increased (p < 0.05), indicating that caerulein combined with LPS successfully induced an experimental acute pancreatitis model in mice. Compared with the SAP group, the levels of serum amylase, lipase, and IL-6 in the EVs (i.p.) group, EVs (i.v.) group, and TOC group of mice were significantly decreased (p < 0.05). HE staining of pancreatic tissue showed that the inflammatory cell infiltration and tissue damage were significantly reduced, and the HE score was significantly decreased (p < 0.05), indicating that both EVs and TOC treatments could effectively improve experimental SAP in mice, and it was confirmed that neutralizing IL-6 could reduce experimental pancreatitis in mice. Although both the EVs treatment group and the TOC treatment group showed significant therapeutic effects in various indicators, the numerical values of various indicators (serum amylase, lipase, IL-6, HE score) in the EVs (i.p.) group and EVs (i.v.) group were lower than those in the TOC group, suggesting that EVs administration might have a better therapeutic effect than TOC treatment ( Figure 3 A-D), but there was no significant difference (ns) between the treatment groups, and further experiments were needed for verification. In addition, for different administration methods of EVs, although there was no significant difference, the serum amylase, lipase, IL-6, and HE score in the EVs (i.p.) group were slightly lower than those in the EVs (i.v.) group, suggesting that compared with intravenous administration, intraperitoneal injection of the same dose of IL6ST-EN144-EVs might have a better therapeutic effect on SAP.

[0063] All in all, both the EVs and TOC treatment methods targeting IL-6 alleviated experimental pancreatitis in mice constructed by caerulein combined with LPS; compared with TOC treatment, EVs had a better therapeutic effect; for different administration methods, intraperitoneal injection of EVs had a better trend of alleviating SAP.

[0064] Example 3

[0065] Therapeutic Effect of Extracellular Vesicle IL6ST-EN144-EVs on Arginine-Induced Acute Pancreatitis Model

[0066] 1. Mouse Preparation

[0067] Before the experiment, the experimental mice were caged and grouped, and a natural control group (NC), a pancreatitis control group (SAP), an engineered extracellular vesicle intraperitoneal injection treatment group (EVs(i.p.)), an engineered extracellular vesicle intravenous injection treatment group (EVs(i.v.)), and a tocilizumab treatment group (TOC) were set up. The mice in each group were fasted but allowed to drink water for 8 hours, labeled and weighed before modeling, and the records were made well.

[0068] 2. Preparation of arginine working solution

[0069] An acute pancreatitis model of mice was constructed using a 20% arginine solution at pH 7.0. Preparation method: Weigh 20 g of arginine powder, dissolve it by adding sterile PBS to a volume of 100 ml, titrate with concentrated hydrochloric acid, and measure the pH to 7.0 (25 °C) using a pH meter. Store it at room temperature and use it freshly prepared.

[0070] 3. Construction of arginine-induced acute pancreatitis model

[0071] An arginine-induced acute pancreatitis model was constructed by intraperitoneal injection of arginine solution in C57BL / 6 mice at a dose of 4 g / kg of mouse body weight, with a total of 2 injections, and the interval between each injection was 1 hour. The mice in the NC group were intraperitoneally injected with an equal volume of sterile PBS.

[0072] 4. Treatment with engineered extracellular vesicles

[0073] At 30 minutes after the completion of acute pancreatitis modeling, the EV(i.p) group and the EV(i.v) group were respectively given 1*10 10 particle numbers of extracellular vesicle IL6ST-EN144-EVs for treatment by intraperitoneal injection and tail vein injection. The NC group was intraperitoneally injected with the same volume of sterile PBS, and the TOC group was intraperitoneally injected with 5 mg / kg of tocilizumab for treatment.

[0074] 5. Observation indicators

[0075] Twelve hours after the modeling and corresponding treatment of the pancreatitis mouse model, blood was collected from the tail vein, the serum was separated and retained, and the levels of serum amylase, lipase, and IL-6 were measured. The mice were euthanized 72 hours after modeling, and the pancreatic tissues were collected for HE staining sections of pancreatic tissues to observe the histopathological changes and conduct pathological scoring. The pathological scoring was evaluated according to the criteria in Table 1. For the observation of the mouse mortality rate, another 3 groups of C57BL / 6 mice were set up, with 34 mice in each group. The EVs(i.p.) group was intraperitoneally injected with 1*10 10 particle numbers of engineered extracellular vesicles for treatment after arginine pancreatitis modeling. The SAP group and the NC group were given the same volume of sterile PBS for administration. Observe for 7 days, record the death situation of the mice in each group, and draw a survival curve.

[0076] 6. Experimental results

[0077] As Figure 4 shown, compared with the mice in the NC group, the levels of serum amylase, lipase and IL-6 in the SAP group were significantly increased (p < 0.05). HE staining of pancreatic tissues showed obvious cellular edema, inflammatory infiltration, acinar cell necrosis and hemorrhage, and the HE score was significantly increased (p < 0.05), indicating that arginine successfully induced an experimental SAP model in mice. Compared with the SAP group, the levels of serum amylase, lipase and IL-6 in the EVs (i.p.) group, EVs (i.v.) group and TOC group were significantly decreased (p < 0.05). HE staining of pancreatic tissues showed that the inflammatory cell infiltration and tissue damage were significantly reduced, and the HE score was significantly decreased (p < 0.05), indicating that both EVs and TOC treatments could effectively improve experimental SAP in mice. Although both the EVs treatment group and the TOC treatment group showed significant therapeutic effects in various indicators, as Figure 4 shown in A.-D., the serum amylase, lipase, IL-6, and HE score in the EVs (i.p.) group were lower than those in the TOC group, suggesting that EVs administration might have a better therapeutic effect than TOC treatment. However, there was no significant difference (ns) between the treatment groups, and further experiments were needed for verification. In addition, for the comparison of different EVs administration methods, although there was no significant difference, the numerical values of various indicators in the EVs (i.p.) group were slightly lower than those in the EVs (i.v.) group, suggesting that intraperitoneal injection of EVs might have a better SAP remission effect compared with i.v. administration. Analysis of the 7-day survival curve of arginine SAP mice showed that the 7-day survival rate of mice in the EVs (i.p.) group was higher than that in the SAP group (survival rate EVs (i.p.): SAP = 67.65%: 52.94%), but the difference did not reach statistical significance (p = 0.0808), indicating that EVs (i.p.) treatment might have a tendency to reduce the mortality of arginine SAP mice ( Figure 4 F.).

[0078] In summary, both EVs and TOC treatments targeting IL-6 alleviated experimental SAP in mice induced by arginine; compared with TOC treatment, EVs seemed to have a better therapeutic effect; for different administration methods, intraperitoneal injection of EVs had a better tendency to relieve SAP.

[0079] In summary, the present invention provides an application of engineered extracellular vesicles targeting IL-6 in the treatment of acute pancreatitis, and the results show that it has significant therapeutic effects in both the SAP mouse model constructed by caerulein combined with LPS and the SAP mouse model induced by arginine. Compared with the clinical drug IL-6 receptor inhibitor TOC, the engineered extracellular vesicles IL6ST-EN144-EVs have better therapeutic effects. For different administration methods, on the premise of the same treatment dose, intraperitoneal injection of IL6ST-EN144-EVs has a better trend of SAP remission. In summary, the engineered extracellular vesicles targeting and neutralizing IL-6 of the present invention provide new ideas and methods for the treatment of acute pancreatitis, and the curative effect is definite.

Claims

1. Use of engineered extracellular vesicles targeting IL-6 in the preparation of a therapeutic drug for acute pancreatitis, characterized in that, The engineered extracellular vesicles are secreted after transfection of Expi293F cells with a plasmid containing IL6ST a fusion gene with a truncated extracellular vesicle scaffold protein EN144 and are extracellular vesicles IL6ST-EN144-EVs that express IL6ST on the surface. The amino acid sequence of the truncated extracellular vesicle scaffold protein EN144 is shown in SEQ ID No.

1.

2. The application according to claim 1, wherein The described inclusion IL6ST with a truncated extracellular vesicle scaffold protein EN144 in the fusion gene IL6ST the gene and EN144 the C-terminus of the gene is fused.

3. The application according to claim 2, characterized in that, The nucleotide sequence of the fusion gene is shown in SEQ ID No.

2.

4. The application according to claim 1, characterized in that, The engineered extracellular vesicles targeting IL-6 are constructed by the following steps: (1) Construct a plasmid containing IL6ST a fusion gene with a truncated extracellular vesicle scaffold protein EN144 ; (2) Transfect the plasmid in step (1) into Expi293F cells to express IL6ST on the surface of the secreted extracellular vesicles, culture the cells, and centrifuge to collect the extracellular vesicles IL6ST-EN144-EVs.

5. The application according to claim 1, wherein The administration method of the acute pancreatitis treatment drug is intravenous injection or intraperitoneal injection.

6. A pharmaceutical composition, characterized in that, Comprising the above-mentioned engineered extracellular vesicles targeting IL-6 and a pharmaceutically acceptable carrier.

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