A human metapneumovirus murine-adapted strain and uses thereof

Abstract

The application belongs to the technical field of biotechnology, and particularly relates to a human metapneumovirus mouse-adapted strain and application thereof. Compared with wild strains, the strain can exhibit stronger susceptibility to animals, and can cause typical clinical symptoms and even death. For example, after the strain infects BALB / c mice, the disease symptoms are obvious, 83% of the mice have a severe decrease in body weight to below 75% after infection, and have reached the humane killing standard. Four days after the strain infects BALB / c mice, the mortality rate is above 50%. The strain can be used to construct a cell model or an animal model of human metapneumovirus infection or a disease caused by the human metapneumovirus, and is further used to screen drugs for preventing and / or treating human metapneumovirus infection or a disease caused by the human metapneumovirus. In addition, the strain can also be used to prepare drugs for preventing and / or treating human metapneumovirus infection or a disease caused by the human metapneumovirus, and to prepare antibodies or antisera against the human metapneumovirus.

Description

A mouse-adapted strain of human metapneumovirus and its application Technical Field

[0001] This invention belongs to the field of biotechnology, specifically relating to a mouse-adapted strain of human metapneumovirus and its applications. Background Technology

[0002] Human metapneumovirus (hMPV) has been prevalent in human communities at high infection levels since its discovery in 2001. hMPV can infect people of all ages, and its infection is mostly self-limiting and often overlooked. However, the elderly, immunocompromised individuals, and children are more susceptible, and hMPV can cause severe respiratory infections, induce secondary infections, and even death. Reports indicate that in 2008, 78% of children under 5 years old with acute lower respiratory tract infections were related to hMPV infection; the proportion of children hospitalized or dying from acute lower respiratory tract infections related to hMPV infection was as high as 79% and 70%, respectively. In recent years, hMPV infection has shown an upward trend, posing a greater threat to children. However, due to the relatively weak infectivity of hMPV and limitations in animal infection models, there are currently no approved specific drugs or vaccines for hMPV. At present, the lack of an ideal animal infection model for hMPV severely hinders research into its pathogenesis and the development of vaccines and drugs. The current methods for establishing hMPV infection models face the following problems: there are few available hMPV infection models, most of which do not show obvious clinical symptoms after infection, or even fail to infect animals. For example, the literature (Small Animal Models for Human Metapneumovirus: Cotton Rat is More Permissive than Hamster and Mouse, Pathogens, 2014 Jul 24; 3(3):633-55, https: / / doi.org / 10.3390 / pathogens3030633) studied the replication and pathogenicity of human metapneumovirus (hMPV) in BALB / c mice and found that BALB / c mice were not sensitive to hMPV infection and no infection virus or viral RNA was detected. Therefore, suitable strains and models still need to be explored. Summary of the Invention

[0003] The first objective of this invention is to provide a human metapneumovirus strain.

[0004] The second aspect of this invention is to provide the application of the human metapneumovirus strain of the first aspect of this invention.

[0005] A third aspect of the present invention is to provide an antibody or antiserum against human metapneumovirus.

[0006] The fourth aspect of this invention is to provide a drug.

[0007] The fifth aspect of this invention aims to provide a method for constructing a cell model of human metapneumovirus infection or diseases caused by it.

[0008] The sixth aspect of this invention aims to provide a cell model of human metapneumovirus infection or diseases caused by it.

[0009] The seventh aspect of this invention aims to provide a method for constructing an animal model of human metapneumovirus infection or diseases caused by it.

[0010] The object of the eighth aspect of the present invention is to provide an application of the cell model of the sixth aspect of the present invention or the method of constructing the seventh aspect of the present invention to obtain an animal model.

[0011] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0012] In a first aspect, the present invention provides a human metapneumovirus strain, wherein the amino acid sequence of the F protein of the strain is shown in SEQ ID NO:6.

[0013] In some embodiments, the nucleotide sequence of the F gene of the strain is shown in SEQ ID NO:5.

[0014] A human metapneumovirus strain, named human metapneumovirus hMPV-B1 / P10 / 202504 and classified as Human Metapneumovirus, was deposited on April 23, 2025, at the China Center for Type Culture Collection (CCTCC) with accession number CCTCC NO: V202530, at Wuhan University, Wuhan, China.

[0015] A second aspect of the invention provides the use of the human metapneumovirus strain of the first aspect of the invention in any one of a1)-a8):

[0016] a1) To prepare drugs for the prevention and / or treatment of human metapneumovirus infection or diseases caused by it;

[0017] a2) Prepare antibodies or antiserum against human metapneumovirus;

[0018] a3) Prepare products for the diagnosis of human metapneumovirus infection or diseases caused by it;

[0019] a4) Detection of human metapneumovirus;

[0020] a5) Construct a cell model of human metapneumovirus infection or the disease it causes;

[0021] a6) Construct animal models of human metapneumovirus infection or the disease it causes;

[0022] a7) Screening for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it;

[0023] a8) Prepare a product, said product being used in any one of a4)-a7).

[0024] In some implementations, the drugs described in a1) and a7) comprise vaccines.

[0025] In some embodiments, the application described in a4) is: the use of the human metapneumovirus strain of the first aspect of the present invention as a positive control in the detection of human metapneumovirus.

[0026] In some implementations, the applications described in a4) and a7) do not involve the diagnosis or treatment of diseases.

[0027] In some implementations, the products described in a3) and a8) include reagents and kits.

[0028] A third aspect of the present invention provides an antibody or antiserum against human metapneumovirus, obtained by immunizing animals with the human metapneumovirus strain of the first aspect of the present invention.

[0029] In some embodiments, the animal is a mammal; further, a non-human mammal; further, a mouse, rat, rabbit, cat, dog, pig, cow, sheep, goat, alpaca, horse, monkey, gorilla, or chimpanzee.

[0030] In a fourth aspect, the present invention provides a medicament comprising: a human metapneumovirus strain of the first aspect of the present invention, or an antibody or antiserum of the third aspect of the present invention.

[0031] In some embodiments, the drug is a vaccine comprising a human metapneumovirus strain according to the first aspect of the present invention.

[0032] In some embodiments, the drug also includes pharmaceutically acceptable excipients.

[0033] In some embodiments, the pharmaceutically acceptable excipients include at least one of diluents, excipients, binders, humectants, surfactants, lubricants, and disintegrants.

[0034] In some embodiments, the drug is in a dosage form suitable for children or for adults.

[0035] In some embodiments, the dosage form is selected from gastrointestinal dosage forms or non-gastrointestinal dosage forms.

[0036] In some embodiments, the gastrointestinal dosage form includes at least one of powder, tablet, granule, capsule, sustained-release, solution, dry suspension, effervescent tablet, emulsion, suspension, syrup, drops, and chewable tablet.

[0037] In some embodiments, the non-gastrointestinal drug delivery dosage forms include at least one of the following: injectable dosage forms (e.g., injections, including various injections such as intravenous injections, intramuscular injections, subcutaneous injections, intradermal injections, and intracavitary injections); respiratory dosage forms (e.g., sprays, aerosols, powder inhalers, etc.); skin dosage forms (e.g., topical solutions, lotions, liniments, ointments, plasters, pastes, patches, etc.); mucosal dosage forms (e.g., eye drops, nasal drops, ophthalmic ointments, mouthwashes, sublingual tablets, adhesive tablets, films, etc.); and cavity dosage forms (e.g., suppositories, aerosols, effervescent tablets, drops, pills, etc., for use in the rectum, vagina, urethra, nasal cavity, ear canal, etc.).

[0038] In some embodiments, the drug is administered to animals.

[0039] In some embodiments, the animal is a mammal; further selected from humans, cats, cattle, sheep, pigs, dogs, chickens, ducks, geese, rabbits, and mice; and even further selected from humans.

[0040] A fifth aspect of the present invention provides a method for constructing a cell model of human metapneumovirus infection or disease caused by it, obtained by infecting cells with the human metapneumovirus strain of the first aspect of the present invention.

[0041] In some embodiments, the cells are derived from animals.

[0042] In some embodiments, the animal includes mammals; further includes at least one of humans and non-human mammals; and further includes non-human mammals.

[0043] In some embodiments, the non-human mammal includes at least one of non-human primates, rodents, cattle, pigs, sheep, dogs, rabbits, cats, and horses; more specifically, rodents.

[0044] In some embodiments, the non-human primates include at least one of orangutans, apes, and monkeys.

[0045] In some embodiments, the rodent includes at least one of mice, rats, hamsters, and guinea pigs; more specifically, mice; and even more specifically, BALB / c mice.

[0046] In some embodiments, the cells comprise primary cells.

[0047] In some embodiments, the primary cells comprise cells derived from the lungs; further, lung epithelial cells; and even further, AT cells (alveolar epithelial cells).

[0048] In some embodiments, the cells include cell lines, further including fibroblast cell lines and epithelial cell lines, such as, but not limited to, Vero cells, WI-38 cells, IMR-90 cells, CCD cells, HSF cells, L929 cells, WML2 mouse lung fibroblasts, NIH-3T3 cells, 16HBE cells, A549 cells, HEK293 cells, MNT-1 cells, HeLa cells, and tMK cells.

[0049] A sixth aspect of the present invention provides a cell model of human metapneumovirus infection or diseases caused thereby, obtained by the construction method of the fifth aspect of the present invention.

[0050] In some embodiments, the cells do not involve reproductive material.

[0051] A seventh aspect of the present invention provides a method for constructing an animal model of human metapneumovirus infection or disease caused by it, obtained by infecting animals with the human metapneumovirus strain of the first aspect of the present invention.

[0052] In some embodiments, the infection method includes at least one of nasal drops, intraperitoneal injection, aerosol exposure, endotracheal inoculation, intrapulmonary inoculation, and oral-pharyngeal inoculation; more specifically, nasal drops.

[0053] In some embodiments, the dose of infection is 3000-7000 FFU per mouse; more specifically, 4000-6000 FFU per mouse.

[0054] In some embodiments, the animal is a non-human animal; further, a non-human mammal; even further, it includes at least one of non-human primates, rodents, cattle, pigs, sheep, dogs, rabbits, cats, and horses; and even further, a rodent.

[0055] In some embodiments, the rodent includes at least one of mice, rats, hamsters, and guinea pigs; more specifically, mice; and even more specifically, BALB / c mice.

[0056] An eighth aspect of the present invention provides the application of the cell model of the sixth aspect of the present invention, or the method of constructing the seventh aspect of the present invention, to an animal model in any one of m1)-m2);

[0057] m1) Screening for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it;

[0058] m2) to prepare products, said products being used to screen for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it.

[0059] In some implementations, the application described in m1) does not involve the diagnosis or treatment of diseases.

[0060] In this invention, the human metapneumovirus comprises at least one of subtype A human metapneumovirus and subtype B human metapneumovirus; further comprises at least one of subtype A1 human metapneumovirus, subtype A2 human metapneumovirus, subtype B1 human metapneumovirus, and subtype B2 human metapneumovirus; even further comprises at least one of subtype B1 human metapneumovirus and subtype B2 human metapneumovirus; and even further comprises subtype B1 human metapneumovirus.

[0061] In this invention, the disease includes at least one of bronchitis, bronchiolitis, pneumonia, upper respiratory tract infection, lower respiratory tract infection, asthma, and otitis media.

[0062] The beneficial effects of this invention are:

[0063] This invention provides a human metapneumovirus strain that, compared to wild-type strains, exhibits stronger susceptibility to animals and can cause typical clinical symptoms and even death. For example, after infecting BALB / c mice with this strain, the disease symptoms are obvious, with 83% of the infected mice experiencing a severe weight loss below 75%, meeting the criteria for humane euthanasia. Furthermore, the mortality rate in BALB / c mice reaches over 50% four days after infection. This strain can be used to construct cell or animal models of human metapneumovirus infection or its caused diseases, and subsequently for screening drugs to prevent and / or treat human metapneumovirus infection or its caused diseases. In addition, this strain can also be used to prepare drugs for the prevention and / or treatment of human metapneumovirus infection or its caused diseases, prepare antibodies or antiserum against human metapneumovirus, prepare products for diagnosing human metapneumovirus infection or its caused diseases, and detect human metapneumovirus, etc. Attached Figure Description

[0064] Figure 1A shows the partial sequence differences of the F protein in hMPV-B1 / GZ / 1712 (wild-type strain).

[0065] Figure 1B shows the results of the differential sequence of the F protein of hMPV-B1-mAT5.

[0066] Figure 1C shows the partial sequence differences of the F protein in hMPV-B1-mAT10.

[0067] Figure 2 shows the trend of mouse body weight under different treatments.

[0068] Figure 3 shows the survival curves of mice under different treatments.

[0069] Figure 4 shows images of AT cells infected with hMPV-B1 / GZ / 1712: A is an image of AT cells infected with MPV-B1 / GZ / 1712 virus; B is a negative control, i.e., an image of AT cells infected with PBS.

[0070] Figure 5 shows the hMPV detection results in the lung tissues of mice under different treatments: A is the hMPV detection result in the lung tissues of mice in the negative control group; B is the hMPV detection result in the lung tissues of mice infected with hMPV-B1 / GZ / 1712 (wild-type strain); C is the hMPV detection result in the lung tissues of mice infected with hMPV-B1-mAT5; and D is the hMPV detection result in the lung tissues of mice infected with hMPV-B1-mAT10.

[0071] Figure 6 shows the hematoxylin and eosin staining of lung tissue from mice under different treatments: A is the hematoxylin and eosin staining of lung tissue from mice in the negative control group; B is the hematoxylin and eosin staining of lung tissue from mice infected with hMPV-B1 / GZ / 1712 (wild-type strain); C is the hematoxylin and eosin staining of lung tissue from mice infected with hMPV-B1-mAT5; and D is the hematoxylin and eosin staining of lung tissue from mice infected with hMPV-B1-mAT10. Detailed Implementation

[0072] The present invention will be further described in detail below through specific embodiments.

[0073] It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0074] Unless otherwise specified, experimental methods in the following examples are generally performed under standard conditions or as recommended by the manufacturer. Unless otherwise specified, the materials and reagents used in these examples are commercially available. For reagents whose manufacturers are listed, similar products from other manufacturers are substituted.

[0075] Example 1. Obtaining and verifying the efficacy of the B1-mAT10 strain

[0076] I. Verification of viral activity of clinical isolate of hMPV subtype B1 (number hMPV-B1 / GZ / 1712)

[0077] 1. Dissect SPF-grade BALB / c mice, collect lungs, thoroughly digest them, filter to obtain lung cell suspension, and separate primary AT cells (alveolar epithelial cells) using flow cytometry.

[0078] 2. Infect the AT cells obtained in “Step 1” with hMPV-B1 / GZ / 1712 virus at an MOI of 1 (negative control group infected with PBS);

[0079] 3. Three days after infection, the infected cells were subjected to immunofluorescence staining to detect the infection status of AT cells.

[0080] The results are shown in Figure 4: the clinical isolate of hMPV subtype B1 (number hMPV-B1 / GZ / 1712) has viral activity and can infect AT cells.

[0081] II. Acquisition of the B1-mAT10 strain

[0082] 1. The clinical isolate of hMPV subtype B1 (number hMPV-B1 / GZ / 1712) was infected with IFN(- / -)C57 mice at a dose of 1x10^5 FFU. Four days after infection, the mice were dissected and lung tissue was removed.

[0083] 2. The lungs of infected mice were thoroughly ground, the supernatant was collected by centrifugation, and the primary hMPV of infected mice was obtained by positive hMPV virus identification.

[0084] 3. Dissect SPF-grade BALB / c mice, collect lungs, thoroughly digest them, filter to obtain lung cell suspension, and separate primary AT cells (alveolar epithelial cells) using flow cytometry for passage of hMPV.

[0085] 4. The hMPV virus obtained in "Step 2" was propagated in isolated primary mouse AT cells, i.e., the hMPV obtained in "Step 2" was inoculated into the primary alveolar epithelial cells obtained in "Step 3". After observing the cytopathic effect (CPE) for 3-7 days, the cells were collected and the cell supernatant was obtained by freeze-thaw centrifugation to obtain the virus.

[0086] 5. The viral titer obtained in "Step 4" is determined by immunofluorescence titration. If the viral titer is less than 10^5 FFU / ml, the virus obtained in "Step 4" is subjected to sucrose ultracentrifugation.

[0087] 6. Repeat steps 4-5 five times, that is, passage the virus in AT cells five times to obtain the hMPV strain, named hMPV-B1-mAT5.

[0088] 7. The hMPV-B1-mAT5 obtained in "Step 6" was prepared into a virus suspension of 1x10^5 FFU / ml. SPF grade BALB / c mice were infected with a dose of 1x10^5 FFU. Four days after infection, the mice were dissected and lung tissue was removed.

[0089] 8. Repeat steps 2 through 6 to obtain the hMPV strain, which is named hMPV-B1-mAT10.

[0090] The strain hMPV-B1-mAT10 is named human metapneumovirus hMPV-B1 / P10 / 202504, classified as HumanMetapneumovirus. It was deposited on April 23, 2025, at the China Center for Type Culture Collection (CCTCC) with accession number CCTCCNO: V202530, located at Wuhan University, Wuhan, China.

[0091] III. Differential sequence analysis of F protein from hMPV-B1 / GZ / 1712 (wild-type strain), hMPV-B1-mAT5, and hMPV-B1-mAT10

[0092]

[0093] IV. Constructing a BALB / c mouse infection model using hMPV-B1 / GZ / 1712 (wild-type strain), hMPV-B1-mAT5, and hMPV-B1-mAT10.

[0094] 1. Set up B1-mAT10 group, B1-mAT5 group, wild-type strain group and negative control group, with 6 animals in each group;

[0095] 2. hMPV-B1-mAT10, hMPV-B1-mAT5 and wild-type strain (hMPV-B1 / GZ / 1712) were respectively prepared into virus suspensions of 10^5 FFU / ml. After deep anesthetizing 6-week-old BALB / c mice, the three hMPV strains were inoculated by intranasal drip at a dose of 50 μl / mouse. The negative control group was replaced with PBS.

[0096] 3. Measure weight and observe and record symptoms for 8 consecutive days after infection;

[0097] 4. On the 4th day after infection, three mice were dissected and lung tissue was collected in duplicate.

[0098] 5. One tissue sample was ground and the viral titer was measured (after euthanasia on day 4 post-infection, lung tissue was taken, the supernatant was used to infect BHK cells, and immunofluorescence was performed using a specific anti-hMPV N protein antibody). Another tissue sample was fixed with paraformaldehyde and then subjected to pathological analysis (after euthanasia on day 4 post-infection, lung tissue was taken, fixed, paraffin-embedded, and stained with hematoxylin and eosin).

[0099] Figures 2-3 and 5-6 show the weight trends, survival curves, lung tissue images on day 4 post-infection (dpi4), viral load in lung tissue, and pathological analysis results of mice under different treatments.

[0100] Mice treated with hMPV-B1-mAT10 experienced a significant and sustained decrease in body weight starting from day one post-infection, peaking at 4-5 days post-infection with a maximum weight loss of up to 28%. Surviving mice began to regain weight at day 5 post-infection. In addition, mice exhibiting significant weight loss also displayed symptoms such as piloerection, altered respiratory status, and reduced food intake. At the point of maximum weight loss, mice exhibited arched backs, extremely low activity levels, and abdominal breathing. By day 4 post-infection, some mice had lost more than 75% of their pre-infection weight; three of these mice were euthanized (according to animal ethics guidelines, the mice's weight was reduced to 75% of pre-infection levels). Humanitarian euthanasia was required for mice whose weight had dropped to the humanitarian euthanasia threshold but who had not yet died. These mice were then euthanized (and considered as deceased cases) and dissected. Upon opening the chest, obvious local lesions were observed in the lungs. Lung tissue was taken, and the supernatant was used to infect BHK cells. Immunofluorescence experiments were performed using a specific anti-hMPV N protein antibody. The cells showed a large amount of green fluorescence, indicating the presence of infectious hMPV virus in the lung tissue. Pathological sections and hematoxylin-eosin staining of the lung tissue showed severe lung lesions, specifically characterized by a reduction in alveoli, thickening of alveolar walls, and extensive infiltration of inflammatory cells.

[0101] Mice treated with hMPV-B1-mAT5 showed only a slight decrease in body weight on the first and second days after infection, followed by recovery. During the experiment, only mild piloerection was observed on the first day after infection, after which the fur became smooth and shiny, and the piloerection did not reappear. They ate and drank normally and were active. Three of the infected mice were euthanized and dissected on the fourth day after infection. No obvious lesions were found in the lungs after thoracotomy. Lung tissue was taken, and the supernatant was used to infect BHK cells. Immunofluorescence experiments were performed using a specific anti-hMPV N protein antibody. A small amount of green fluorescence was observed in the cells, indicating that hMPV virus could be isolated from the lung tissue. Pathological sections and hematoxylin and eosin staining of the lung tissue showed that the lung lesions were milder compared to the PBS group mice, specifically mild thickening of the alveolar walls and a small amount of inflammatory cell infiltration.

[0102] Mice treated with the wild-type strain (hMPV-B1 / GZ / 1712) did not show significant and sustained weight loss throughout the experimental period; their fur was smooth and shiny, without any hair piloerection; they ate and drank normally and were active; three infected mice were euthanized and dissected on the fourth day after infection. Upon thoracotomy, the lung tissue was found to be uniformly pink without any lesions; lung tissue was collected, and the supernatant was used to infect BHK cells. Immunofluorescence experiments were performed using a specific anti-hMPV N protein antibody. A small amount of green fluorescence was observed in the cells, indicating that hMPV virus was isolated from the lung tissue; pathological sections and hematoxylin-eosin staining of the lung tissue showed that the alveolar structure was normal and no large number of immune cell infiltrations were observed.

[0103] Mice in the negative control group did not show significant and persistent weight loss throughout the experimental period; their fur was smooth and shiny, and no hair piloerection was observed; they ate and drank normally and were active; three mice were euthanized and dissected on the fourth day after infection. Upon thoracotomy, the lung tissue was found to be uniformly pink with no lesions; lung tissue was taken, and the supernatant was used to infect BHK cells. Immunofluorescence experiments were performed using a specific anti-hMPV N protein antibody. No green fluorescence was observed in the cells, indicating that no hMPV virus was isolated from the lung tissue; pathological sections and hematoxylin-eosin staining of the lung tissue showed that the alveolar structure was normal and no large number of immune cell infiltrations were observed.

[0104] The technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made in accordance with the technical solutions of the present invention fall within the protection scope of the present invention.

Claims

1. A human metapneumovirus strain, named human metapneumovirus hMPV-B1 / P10 / 202504, was deposited on April 23, 2025 at the China Center for Type Culture Collection (CCTCC) with accession number CCTCC NO: V202530, at Wuhan University, Wuhan, China.

2. The human metapneumovirus strain according to claim 1, characterized in that, The amino acid sequence of the F protein of the strain is shown in SEQ ID NO:

6.

3. The human metapneumovirus strain according to claim 2, characterized in that, The nucleotide sequence of the F gene of the strain is shown in SEQ ID NO:

5.

4. The use of the human metapneumovirus strain according to any one of claims 1-3 in any one of a1)-a6): a1) preparing a product for diagnosing human metapneumovirus infection or diseases caused by it; a2) detecting human metapneumovirus for non-diagnostic purposes, wherein the human metapneumovirus strain serves as a positive control; a3) constructing a cell model of human metapneumovirus infection or diseases caused by it, wherein the cells are derived from mice; a4) constructing an animal model of human metapneumovirus infection or diseases caused by it, wherein the animal is a mouse; a5) screening for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it; a6) preparing a product used for any one of the following: as a positive control for detecting human metapneumovirus, constructing a cell model of human metapneumovirus infection or diseases caused by it, constructing an animal model of human metapneumovirus infection or diseases caused by it, and screening for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it; wherein the cells are derived from mice, and the animal is a mouse.

5. A method for constructing a cell model of human metapneumovirus infection or its disease, wherein cells are obtained by infecting cells with the human metapneumovirus strain described in any one of claims 1-3, wherein the cells are derived from mice.

6. The construction method according to claim 5, characterized in that, The cells include primary cells.

7. The construction method according to claim 6, characterized in that, The primary cells include cells derived from the lungs.

8. The construction method according to claim 7, characterized in that, The primary cells include lung epithelial cells.

9. The construction method according to claim 8, characterized in that, The primary cells include alveolar epithelial cells.

10. The construction method according to claim 5, characterized in that, The cells are derived from a cell line.

11. The construction method according to claim 10, characterized in that, The cell line in question is an epithelial cell line.

12. A cell model of human metapneumovirus infection or disease caused therefrom, obtained by the construction method according to any one of claims 5-11.

13. A method for constructing an animal model of human metapneumovirus infection or disease caused by it, wherein the animal is a mouse, and the animal is infected with the human metapneumovirus strain described in any one of claims 1-3.

14. The construction method according to claim 13, characterized in that, The method of infection is nasal drops.

15. The construction method according to claim 14, characterized in that, The animal in question was a BALB / c mouse.

16. The application of the cell model of claim 12 or the construction method of any one of claims 13-15 to obtain an animal model in any one of m1)-m2); m1) screening for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it; m2) preparing a product for screening for drugs to prevent and / or treat human metapneumovirus infection or diseases caused by it.

Images