Construction method of psoriasis animal model

Abstract

The invention discloses a construction method of a psoriasis animal model, belongs to the technical field of psoriasis animal model construction, and constructs an animal model of T cell mediated chronic inflammatory psoriasis through the steps of laboratory mouse feeding, modeling mouse feeding and model construction. According to the method, fatigue training is carried out on a mouse in the modeling mouse feeding period, the living law of the mouse is disrupted, the living state of a psoriasis patient before illness can be simulated, induction factors of psoriasis can be increased, fMLP is smeared in the model building period, noise interference is carried out on the mouse, the built model can well reflect the attack law of psoriasis, and the model has a good application prospect. The constructed model is an ideal psoriasis animal model.

Description

Technical Field

[0001] The present invention relates to the technical field of constructing psoriasis animal models, and in particular to a method for constructing a psoriasis animal model. Background Art

[0002] Psoriasis, commonly known as psoriasis, is a chronic inflammatory skin disease with a long course and a tendency to relapse. Some cases are almost never cured. The clinical manifestations are mainly erythema and scaling. It can occur all over the body, but is more common on the scalp and extensor side of the limbs. The disease mainly occurs in young and middle-aged people, and has a great impact on the patient's physical health and mental state.

[0003] Psoriasis is rare in non-human animals, and the proportion of natural occurrence is extremely small, which hinders the scientific research on psoriasis. Therefore, it is extremely important to construct an animal model of psoriasis. The conventional method is to construct an animal model of psoriasis by applying 5% imiquimod ointment topically to the depilated skin of the back or ear. The model construction method has the advantages of low cost, strong operability, good repeatability, short modeling time and high similarity of skin lesions. Therefore, it has become the most widely used animal model in preclinical psoriasis research. However, the model constructed by this method is an acute induction model, which is an acute inflammatory reaction and cannot fully reproduce the chronic inflammatory state of psoriasis. In addition, drug tolerance and adaptation may occur under the continuous action of topical imiquimod ointment, resulting in a significant tendency of skin lesions to be self-limited. In addition, psoriasis is a chronic skin disease with a very complex etiology. It is currently recognized that psoriasis is caused by the combined action of multiple factors such as genetic factors, environmental factors, and immune factors. When imiquimod is conventionally used to construct an animal model of psoriasis, the influence of environmental factors is usually not considered.

[0004] Therefore, it is necessary to find a method to construct an animal model of psoriasis that can reproduce the chronic inflammatory state of psoriasis and is less prone to drug tolerance and adaptation. Summary of the invention

[0005] In view of this, the purpose of the present invention is to provide a method for constructing an animal model of psoriasis, so as to solve the problem that the conventional method of using imiquimod ointment to construct an animal model of psoriasis cannot fully reproduce the chronic inflammatory state of psoriasis, and is prone to drug tolerance and adaptation phenomena, and does not reflect the situation of combined induction by other factors.

[0006] The present invention solves the above technical problems by the following technical means:

[0007] A method for constructing a psoriasis animal model, wherein the psoriasis animal model is constructed by applying fMLP (N-formyl-methylsulfonyl-leucyl-phenylalanine).

[0008] The N-formyl peptide receptor (FPR1) is highly activated in the psoriasis epidermis, and it is a high-affinity receptor for fMLP. The inventors found through experiments that by applying fMLP to the mouse skin, fMLP highly binds to the N-formyl peptide receptor, making the N-formyl peptide receptor (FPR1) highly activated in the epidermis. Therefore, fMLP can be used to construct a T cell-mediated chronic inflammatory psoriasis animal model.

[0009] However, psoriasis is a common chronic skin disease with a very complex etiology. It is currently recognized that psoriasis is caused by the combined effects of genetic factors, environmental factors, immune factors, and other factors. To make the constructed animal model more reliable, it is necessary to perform multi-factor treatment on the animals used to construct the model. Therefore, after constructing the fMLP-induced model, multi-factor combined induction was also performed. Specifically, fatigue and irregular lifestyle are factors that induce psoriasis. When constructing psoriasis mice, the mice are first fed in advance, run to make them tired, change the light exposure time to make them live an irregular life, and make noise interference to make the mice nervous and anxious, so as to better simulate the state of psoriasis patients before the onset of the disease. Through the combined effects of multiple factors and fMLP agents, mice are induced to develop the disease, and a psoriasis mouse model is constructed. The obtained psoriasis mouse model can better simulate the complex causes of psoriasis, and the obtained model is more reliable.

[0010] Further, the construction method is specifically as follows:

[0011] S1: Experimental mice feeding: Experimental mice were obtained by feeding mice with free access to food and water in a standard manner;

[0012] S2: Feeding of model mice: feeding experimental mice with different lighting schedules for 7-10 days to obtain model mice, during which the mice were allowed to run for 1-2 hours every day at a speed of 15-25 m / min;

[0013] S3: Model construction: Remove the hair on the back or ears of the modeling mice, and then apply fMLP agent to the hair removal area of ​​the modeling mice to construct a psoriasis animal model. Change the dressing every 3 days. When changing the dressing, spray the stripping agent to strip off the old agent and then apply the new agent. The agent is applied 6-7 times in total.

[0014] Furthermore, in step S1, the standard feeding temperature is 20-25° C., the humidity is 50-60%, the lighting time is 12 h light / 12 h dark, the light intensity is 15-20 lx, and the ventilation frequency is 8-12 times / day.

[0015] Furthermore, the feeding time of the experimental mice in step S1 is: 33-40 days for females and 43-50 days for males.

[0016] Psoriasis often occurs in young adults. The use of young mice to construct an animal model of psoriasis can better reflect the characteristics of psoriasis and is more conducive to the study of psoriasis. Since the experimental mice need to be pre-fed later, the feeding time of the experimental mice is 33-40 days for females and 43-50 days for males. After the experimental mice are fed, they are pre-fed again, and the mice are in their youth when the model is constructed.

[0017] Furthermore, in step S2, the light duration during mouse feeding is adjusted to (4-6) h light / (18-20) h dark.

[0018] Further, the fMLP preparation method is as follows:

[0019] Add chitosan to 2wt% acetic acid solution and stir to dissolve, then add 2,3-butanedione, heat to 45-55°C and stir to react for 30-60min, after the reaction is completed, keep it at room temperature for 4-8h, then add n-butyl acetate, stir to react at room temperature for 10-20min, then add glycerol and mix evenly, then adjust the pH to 4-5, add sodium β-glycerophosphate and fMLP, stir and mix at 4°C for 15-20min to obtain fMLP agent, and store at 4°C for use.

[0020] Furthermore, the mass ratio of chitosan to 2wt% acetic acid solution, 2,3-butanedione, n-butyl acetate, glycerol, sodium β-glycerophosphate, and fMLP is (2-5): (60-90): (1-2): (0.5-1): (1-2): (1.6-2): (1.5-2.2).

[0021] Further, the stripping agent preparation method is as follows:

[0022] L-cysteine ​​and hyaluronic acid were sequentially added into water in a mass ratio of 1:2, and stirred to dissolve to obtain a peeling agent.

[0023] Furthermore, when constructing the model in step S3, the mice are subjected to intermittent noise interference every 4 days, with a decibel level of 75-80 dB, a duration of 0.5-1 h, and a frequency of 3-5 times / day.

[0024] In the modeling process, the present invention simulates the pre-onset state of psoriasis patients by adjusting various environmental factors at different stages, and constructs a psoriasis mouse model in combination with fMLP agent. However, during the model construction process, mice will scratch and clean the medication site, which will not only clean up the drug solution on the one hand, but also clean up the dandruff appearing at the medication site on the other hand, affecting the modeling process and the accuracy of the modeling results. Therefore, the present invention uses chitosan as a carrier to load fMLP to prepare a temperature-sensitive gel-type agent, and then applies it. The prepared agent can gel quickly and firmly adhere to the medication site, thereby preventing mice from scratching and cleaning the medication site, thereby better solving the aforementioned problems.

[0025] Specifically, the present invention first dissolves chitosan and then reacts it with 2,3-butanedione, 2,3-butanedione chemically bonds with the surface groups of chitosan, changes the surface chemical properties of chitosan, improves the interaction between chitosan and the skin surface when forming a gel, thereby enhancing the adhesion of the agent on the skin surface, so that the agent can be more firmly adhered to the medication site; further, the present invention also adds n-butyl acetate to the agent, and in the process of applying the agent to form a gel, n-butyl acetate hydrolyzes acetic acid and further forms a negatively charged deprotonated carboxyl group, which electrostatically interacts with the surface groups of chitosan, thereby promoting the aggregation of chitosan molecular chains and shortening the gelation time of the agent. After the fMLP agent is applied, it quickly forms and firmly adheres to the skin surface at the medication site, which can not only reduce the waste of liquid medicine, but also physically protect the medication site, prevent mice from scratching and cleaning the medication site, and facilitate observation and detection of the skin lesions of mice after modeling.

[0026] When changing the dressing, a stripping agent is sprayed first. L-cysteine ​​in the stripping agent acts on the chitosan gel to promote its swelling, and then hyaluronic acid further enters to destroy the bond between the chitosan gel and the skin surface, quickly reducing the adhesion of the agent on the skin surface, thereby easily stripping off the old agent, facilitating the replacement of the new agent to promote the smooth progress of modeling, and preventing and controlling damage to the mouse skin caused by pulling. The present invention uses chitosan and other materials as raw materials to prepare a gel, load the effective ingredient fMLP, and then apply it to the mouse skin surface, and jointly construct a psoriasis animal model with a stripping agent. The gel and the stripping agent can cooperate with the effective ingredients to better model while not affecting the modeling results, and can work together to construct an ideal psoriasis animal model.

[0027] Beneficial effects:

[0028] 1. The present invention constructs a T cell-mediated chronic inflammatory psoriasis animal model by applying fMLP to mouse skin. The model can better simulate the chronic pathogenesis of psoriasis and is an ideal psoriasis animal model.

[0029] 2. The present invention simulates the fatigue and irregular life state of people before becoming ill before constructing the model, and simulates the patient's anxious mental state during the construction process, thereby reflecting the complex characteristics of psoriasis, and can better reproduce the characteristics of the disease, and the constructed model is more reliable.

[0030] 3. The present invention adopts a specific method to prepare the drug into a thermosensitive gel for application. The prepared drug can gel quickly and firmly adhere to the medication site, reducing the waste of liquid medicine, while preventing mice from scratching and cleaning the medication site, causing dandruff to fall off and affecting the modeling process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 : Pictures of the ear conditions of blank control group mice (A), experimental group mice (B), and control group mice (C) 10 days after the establishment of the psoriasis mouse model of the present invention;

[0032] Figure 2 :This is a picture of the immunofluorescence detection of inflammatory cell infiltration inside the ear of the present invention;

[0033] Figure 3 :It is a picture of the expression of inflammatory factors detected by RT-PCR of the present invention;

[0034] Figure 4 : Pictures of the ear conditions at different times when the IMQ and fMLP mouse models of the present invention were established;

[0035] Figure 5 : Pictures showing different trends of ear thickening in the IMQ and fMLP mouse models of the present invention. DETAILED DESCRIPTION

[0036] The present invention will be described in detail below with reference to specific embodiments and accompanying drawings:

[0037] The mice used in the present invention were selected from 15-day-old BALB / c male mice raised in the Animal Experiment Center of Air Force Medical University and fed with free access to food and water. The drug fMLP used was purchased from MCE with the item number HY-P0224.

[0038] The present invention discloses a method for constructing an animal model of psoriasis. Before constructing the model, fMLP (N-formyl-methylthioyl-leucyl-phenylalanine) needs to be prepared into a medicine for smearing modeling. The specific method for preparing the medicine is as follows.

[0039] Example 1: fMLP preparation

[0040] Add 4 g of chitosan to 80 g of 2 wt% acetic acid solution and stir to dissolve, then add 1.5 g of 2,3-butanedione, heat to 50 °C and stir to react for 40 min, after the reaction is completed, keep it at room temperature for 6 h, then add 0.8 g of n-butyl acetate, stir to react at room temperature for 15 min, then add 1.5 g of glycerol and mix evenly, then adjust the pH to 4.5, add 1.8 g of sodium β-glycerophosphate and 1.8 g of fMLP, stir to react at 4 °C for 16 min to obtain fMLP agent, and store at 4 °C for use.

[0041] Example 2: fMLP preparation

[0042] Add 2g of chitosan to 60g of 2wt% acetic acid solution and stir to dissolve, then add 1g of 2,3-butanedione, heat to 45°C and stir to react for 60min, after the reaction is completed, keep it at room temperature for 4h, then add 0.5g of n-butyl acetate, stir to react at room temperature for 10min, then add 1g of glycerol and mix evenly, then adjust the pH to 4, add 1.6g of sodium β-glycerophosphate and 1.5g of fMLP, stir to react at 4°C for 20min to obtain fMLP agent, and store at 4°C for use.

[0043] Example 3: fMLP preparation

[0044] Add 5g of chitosan to 90g of 2wt% acetic acid solution and stir to dissolve, then add 2g of 2,3-butanedione, heat to 55°C and stir to react for 60min, after the reaction is completed, keep it at room temperature for 8h, then add 1g of n-butyl acetate, stir to react at room temperature for 12min, then add 2g of glycerol and mix evenly, then adjust the pH to 5, add 2g of sodium β-glycerophosphate and 2.2g of fMLP, stir to react at 4°C for 20min to obtain fMLP agent, and store at 4°C for use.

[0045] Comparative Example 1: fMLP preparation

[0046] In contrast to Example 1, the only difference is that 2,3-butanedione is not added during the preparation of the agent in Comparative Example 1, as shown below:

[0047] Add 4 g of chitosan to 80 g of 2 wt% acetic acid solution and stir to dissolve, then add 0.8 g of n-butyl acetate, stir and react at room temperature for 15 min, then add 1.5 g of glycerol and mix evenly, then adjust the pH to 4.5, add 1.8 g of sodium β-glycerophosphate and 1.8 g of fMLP, stir and react at 4°C for 16 min to obtain fMLP agent, and store at 4°C for use.

[0048] Comparative Example 2: fMLP preparation

[0049] In contrast to Example 1, the only difference is that n-butyl acetate is not added during the preparation of the agent in Comparative Example 2, as shown below:

[0050] Add 4 g of chitosan to 80 g of 2 wt% acetic acid solution and stir to dissolve, then add 1.5 g of 2,3-butanedione, heat to 50 °C and stir to react for 40 min, after the reaction is completed, leave it at room temperature for 6 h, then add 1.5 g of glycerol and mix well, adjust the pH to 4.5, add 1.8 g of sodium β-glycerophosphate and 1.8 g of fMLP, stir to react at 4 °C for 16 min to obtain fMLP agent, and store at 4 °C for use.

[0051] Comparative Example 3: fMLP preparation

[0052] In contrast to Example 1, the only difference is that glycerol is not added during the preparation of the medicament in Comparative Example 3, as shown below:

[0053] Add 4 g of chitosan to 80 g of 2 wt% acetic acid solution and stir to dissolve, then add 1.5 g of 2,3-butanedione, heat to 50 °C and stir to react for 40 min, after the reaction is completed, keep it at room temperature for 6 h, then add 0.8 g of n-butyl acetate, stir to react at room temperature for 15 min, adjust the pH to 4.5, add 1.8 g of sodium β-glycerophosphate and 1.8 g of fMLP, stir to react at 4 °C for 16 min to obtain fMLP agent, and store at 4 °C for use.

[0054] Comparative Example 4: fMLP preparation

[0055] In contrast to Example 1, the only difference is that the pH of the medicament in Comparative Example 4 is adjusted to 3 during preparation, as shown below:

[0056] Add 4 g of chitosan to 80 g of 2 wt% acetic acid solution and stir to dissolve, then add 1.5 g of 2,3-butanedione, heat to 50 °C and stir to react for 40 min, after the reaction is completed, keep it at room temperature for 6 h, then add 0.8 g of n-butyl acetate, stir to react at room temperature for 15 min, then add 1.5 g of glycerol and mix evenly, then adjust the pH to 3, add 1.8 g of sodium β-glycerophosphate and 1.8 g of fMLP, stir to react at 4 °C for 16 min to obtain fMLP agent, and store at 4 °C for use.

[0057] Comparative Example 5: fMLP preparation

[0058] In contrast to Example 1, the only difference is that the pH of the medicament in Comparative Example 5 is adjusted to 6 during preparation, as shown below:

[0059] Add 4 g of chitosan to 80 g of 2 wt% acetic acid solution and stir to dissolve, then add 1.5 g of 2,3-butanedione, heat to 50 °C and stir to react for 40 min, after the reaction is completed, keep it at room temperature for 6 h, then add 0.8 g of n-butyl acetate, stir to react at room temperature for 15 min, then add 1.5 g of glycerol and mix evenly, then adjust the pH to 6, add 1.8 g of sodium β-glycerophosphate and 1.8 g of fMLP, stir to react at 4 °C for 16 min to obtain fMLP agent, and store at 4 °C for use.

[0060] Example 4: Stripping agent preparation

[0061] 10 g of L-cysteine ​​and 20 g of hyaluronic acid were added to 300 g of water in sequence, stirred, mixed and dissolved to obtain a peeling agent.

[0062] Comparative Example 6: Stripping Agent Preparation

[0063] In contrast to Example 4, the only difference is that L-cysteine ​​is not added when preparing the stripping agent in Comparative Example 6, as shown below:

[0064] 20 g of hyaluronic acid was added into 200 g of water and stirred to dissolve to obtain a peeling agent.

[0065] Comparative Example 7: Stripping Agent Preparation

[0066] In contrast to Example 4, the only difference is that hyaluronic acid is not added when preparing the exfoliant in Comparative Example 7, as shown below:

[0067] 10 g of L-cysteine ​​was added into 100 g of water and stirred to dissolve to obtain a stripping agent.

[0068] Experiment 1: fMLP agent performance test

[0069] The gelation time and adhesion strength of the fMLP agents prepared in Example 1 and Comparative Examples 1-5 (specifically, the adhesion strength of the agents to the pig skin surface at 37° C. was tested using a vertical peeling method) were measured, and the data obtained are shown in Table 1:

[0070] Table 1

[0071]

[0072] According to the data analysis in Table 1:

[0073] The drug prepared in Example 1 has a fast gelling speed and high adhesion strength, indicating that the drug prepared according to the method of the present invention can be quickly gelled and firmly attached to the medication area on the mouse body surface after application, and then slowly release the drug to construct a psoriasis mouse model. This can not only reduce the waste of drug solution, but also the firmly attached gel can prevent the mouse from scratching and cleaning the medication area, which is conducive to ensuring the smooth construction of the model and the reliability of the constructed model.

[0074] In Comparative Example 1, 2,3-butanedione was not added during the preparation of the agent, and the adhesion of the agent was reduced; in Comparative Example 2, n-butyl acetate was not added during the preparation of the agent, and the aggregation of molecular chains during gel formation was not promoted, resulting in a long gelation time; in Comparative Examples 4 and 5, the pH was adjusted to 3 and 6, respectively, during the preparation of the agents, and the change in pH affected the hydrolysis of n-butyl acetate, thereby affecting the gelation time of the gel.

[0075] Experiment 2: Stripping agent performance measurement

[0076] The performance of the stripping agents prepared in Example 4 and Comparative Examples 6-7 was measured. The adhesion strength of the agent after spraying the stripping agent for 10 minutes at 37° C. was measured according to the same vertical stripping method as in Experiment 1 (recorded as adhesion strength B). The data obtained are shown in Table 2:

[0077] Table 2

[0078] Example 4 Comparative Example 6 Comparative Example 7 Adhesion strength B(kPa) 1.9 3.2 3.8

[0079] According to the data analysis in Table 2:

[0080] The stripping agent prepared by the present invention can act on the medicine well, reduce its adhesion, and then it is easier to strip it off, ensuring the smooth progress of the dressing change.

[0081] Experiments 1 and 2 tested the performance of the agent and peeling agent prepared by the present invention, and the performance was good. Therefore, the fMLP agent was prepared according to the method of Example 1 of the present invention, and the peeling agent was prepared according to the method of Example 4. The prepared fMLP agent and peeling agent were used to carry out an experiment to construct a mouse psoriasis model. The specific construction method is as follows.

[0082] Experiment 3: Construction and testing of psoriasis mouse model

[0083] 1. Experimental group (fMLP) psoriasis mouse modeling:

[0084] S1: Experimental mouse feeding: The selected experimental mice were 15-day-old mice under free feeding, so the mice were fed according to the standard feeding method of free food and free water to obtain experimental mice. Specifically, the standard feeding conditions were temperature of 24°C, humidity of 55%, lighting time of 12h light / 12h dark, light intensity of 20lx, ventilation frequency of 10 times / day, and feeding was continued for 30 days according to the standard feeding conditions;

[0085] S2: Feeding of model mice: The experimental mice were fed under the conditions of 5h light / 19h dark for 8 days to obtain model mice weighing about 30g. During this period, the mice were allowed to run for 1.5h every day at a speed of 20m / min;

[0086] S3: Model construction: The ear hair of the modeling mice was removed, and then fMLP agent was applied to the depilated area of ​​the modeling mice to construct a psoriasis animal model. The application thickness was about 0.5mm, and the dressing was changed every 3 days. When changing the dressing, the stripping agent was sprayed to strip off the old agent and then the new agent was applied. The agent was applied 6 times in total, and the mice were subjected to intermittent noise interference every 4 days, with a decibel of 75dB, a time of 0.5h, and a frequency of 4 times / day.

[0087] 2. Construction of psoriasis mouse model in control group (IMQ)

[0088] In contrast to the experimental group, the only difference was that when constructing the mouse model in the control group, 50 mg of 5% imiquimod ointment was applied daily for 15 days according to the conventional method, and the rest of the steps were the same as those of the experimental group.

[0089] 3. Blank control mice (WT)

[0090] In the blank control group, no active ingredient fMLP was added during the preparation of the drug, and the specific preparation method was as follows:

[0091] Add 4g chitosan to 80g 2wt% acetic acid solution and stir to dissolve, then add 1.5g 2,3-butanedione, heat to 50℃ and stir to react for 40min, after the reaction is completed, leave it at room temperature for 6h, then add 0.8g n-butyl acetate, stir to react for 15min at room temperature, then add 1.5g glycerol and mix well, then adjust the pH to 4.5, add 1.8g sodium β-glycerophosphate, stir to react at 4℃ for 16min to obtain a blank reagent, and store at 4℃ for use;

[0092] The mice were fed according to the psoriasis mouse modeling method of the experimental group, and blank agents were applied as blank controls with an application thickness of about 0.5 mm. The dressing was changed every 3 days. When changing the dressing, a stripping agent was sprayed to strip off the old blank agent and then a new blank agent was applied.

[0093] Result analysis:

[0094] On the 10th day after the application of the drug, the ear conditions of the experimental group mice, the control group mice and the blank control group mice were observed. The results are as follows: Figure 1 As shown, the ears of mice in the experimental group and the control group showed obvious psoriasis ( Figure 1 :A is blank control group, B is experimental group, C is control group). The blank control group mice did not show psoriasis on their ears ( Figure 1 :A), indicating that the mouse psoriasis animal model was successfully established. Immunofluorescence was further used to detect the infiltration of inflammatory cells in the ears of each group of mice ( Figure 2 );RT-PCR detection of inflammatory factors expression ( Figure 3 ) and the ear thickening of each group of mice was observed ( Figure 4 , Figure 5 ).

[0095] according to Figure 2 , Figure 3 It can be seen that in the fMLP experimental group, T cells infiltrated the lesions, and IL-17, IL-25, and CXCL-1 were highly expressed in the lesions, indicating that topical application of fMLP can induce the key features of psoriasis and cause psoriasis;

[0096] according to Figure 4 , Figure 5 It can be seen that: compared with the imiquimod (IMQ) model, the ears of the fMLP mouse model will have persistent psoriasis. The psoriasis animal model constructed by fMLP is a chronic inflammatory psoriasis animal model, and the ear thickness of the fMLP mouse model will continue to maintain after reaching the peak value, indicating that mice are not easy to develop resistance to fMLP, and a reliable psoriasis animal model can be constructed by fMLP; while in the imiquimod (IMQ) model, mice are prone to develop resistance to imiquimod, and then the skin lesions tend to be self-limiting, indicating that the fMLP mouse psoriasis model constructed according to the method of the present invention is more ideal than the imiquimod mouse psoriasis model constructed by the traditional method.

[0097] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions of the present invention, which should be included in the scope of the claims of the present invention. The techniques, shapes, and structural parts not described in detail in the present invention are all known technologies.

Claims

1. A method for constructing an animal model of psoriasis, characterized in that: The psoriasis animal model was constructed by applying fMLP.

2. The method for constructing an animal model of psoriasis according to claim 1, characterized in that: The construction method is specifically as follows: S1: Experimental mice feeding: Experimental mice were obtained by feeding mice with free access to food and water in a standard manner; S2: Feeding of model mice: feeding experimental mice with different lighting schedules for 7-10 days to obtain model mice, during which the mice were allowed to run for 1-2 hours every day at a speed of 15-25 m / min; S3: Model construction: Remove the hair on the back or ears of the modeling mice, and then apply fMLP agent to the hair removal area of ​​the modeling mice to construct a psoriasis animal model. Change the dressing every 3 days. When changing the dressing, spray the stripping agent to strip off the old agent and then apply the new agent. The agent is applied 6-7 times in total.

3. The method for constructing an animal model of psoriasis according to claim 2, characterized in that: The standard feeding temperature in step S1 is 20-25° C., the humidity is 50-60%, the lighting time is 12 h light / 12 h dark, the light intensity is 15-20 lx, and the ventilation frequency is 8-12 times / day.

4. The method for constructing an animal model of psoriasis according to claim 3, characterized in that: The feeding period of the experimental mice in step S1 is: 33-40 days for females and 43-50 days for males.

5. The method for constructing an animal model of psoriasis according to claim 4, characterized in that: In step S2, the light duration during mouse feeding is adjusted to (4-6) h light / (18-20) h dark.

6. The method for constructing an animal model of psoriasis according to claim 5, characterized in that: The fMLP preparation method is as follows: Add chitosan to 2wt% acetic acid solution and stir to dissolve, then add 2,3-butanedione, heat to 45-55°C and stir to react for 30-60min, after the reaction is completed, keep it at room temperature for 4-8h, then add n-butyl acetate, stir to react at room temperature for 10-20min, then add glycerol and mix evenly, then adjust the pH to 4-5, add sodium β-glycerophosphate and fMLP, stir and mix at 4°C for 15-20min to obtain fMLP agent, and store at 4°C for use.

7. The method for constructing an animal model of psoriasis according to claim 6, characterized in that: The mass ratio of chitosan to 2wt% acetic acid solution, 2,3-butanedione, n-butyl acetate, glycerol, sodium β-glycerophosphate, and fMLP is (2-5): (60-90): (1-2): (0.5-1): (1-2): (1.6-2): (1.5-2.2).

8. The method for constructing an animal model of psoriasis according to claim 7, characterized in that: The stripping agent preparation method is as follows: L-cysteine ​​and hyaluronic acid were sequentially added into water in a mass ratio of 1:2, and stirred to dissolve to obtain a peeling agent.

9. The method for constructing an animal model of psoriasis according to claim 8, characterized in that: When constructing the model in step S3, the mice are subjected to intermittent noise interference every 4 days, with a decibel level of 75-80 dB, a duration of 0.5-1 h, and a frequency of 3-5 times / day.

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