Application of E2F2 in inhibition of HIV-1 and HIV-2 proliferation

Abstract

The invention discloses application of E2F2 in inhibition of HIV-1 and HIV-2 proliferation, and particularly relates to application of any one of substances shown in (1)-(3) in at least one of substances shown in (a)-(c): (1) E2F2 protein; (2) a nucleic acid molecule encoding the E2F2 protein; (3) an expression cassette, a recombinant vector or a transgenic cell containing the nucleic acid molecule; (a) inhibiting the proliferation of HIV-1 in cells, or preparing a product for inhibiting the proliferation of HIV-1 in cells; (b) inhibiting the proliferation of the HIV-2 in the cells, or preparing a product for inhibiting the proliferation of the HIV-2 in the cells; and (c) inhibiting the proliferation of SIVnano in the cells, or preparing a product for inhibiting the proliferation of SIVnano in the cells.

Description

Technical Field

[0001] The present invention relates to the field of biomedicine, and particularly to the application of E2F2 overexpression in inhibiting or treating HIV infection. Background Art

[0002] Untreated HIV replication leads to the progressive loss of CD4+ T cells and widespread immune abnormalities, increasing the risk of infection and tumor complications. HIV infection also causes several common diseases such as cardiovascular diseases, bone diseases, and renal and liver dysfunctions. Antiretroviral drugs are very effective in inhibiting HIV replication. For individuals who can obtain and use antiretroviral drugs, adherence to these drugs and combination antiretroviral therapy can lead to persistent (and possibly lifelong) viral replication inhibition. Viral inhibition enables immune restoration and nearly eliminates the risk of developing acquired immunodeficiency syndrome (AIDS).

[0003] E2F transcription factor 2 (E2F2) is a member of the E2F transcription factor family. The classical view is that some E2Fs play seemingly contradictory roles in the cell cycle, proliferation, apoptosis, inflammation, cell migration, and invasion as "activators" and other "inhibitors" of cell cycle gene expression. However, the role of E2F2 in viral infection has been relatively less studied, and whether E2F2 has anti-HIV infection function and its mechanism are still unclear. Summary of the Invention

[0004] The object of the present invention is to provide an application of E2F2 in inhibiting the proliferation of HIV-1 and HIV-2.

[0005] The present invention claims the application of any one of the substances shown in the following (1)-(3) in at least one of the following (a)-(c):

[0006] (1) E2F2 protein;

[0007] (2) Nucleic acid molecule encoding E2F2 protein;

[0008] (3) Expression cassette, recombinant vector or transgenic cell containing the nucleic acid molecule;

[0009] (a) Inhibiting the proliferation of HIV-1 in cells, or preparing a product for inhibiting the proliferation of HIV-1 in cells;

[0010] (b) Inhibiting the proliferation of HIV-2 in cells, or preparing a product for inhibiting the proliferation of HIV-2 in cells;

[0011] (c) Inhibiting the proliferation of SIVnano in cells, or preparing a product for inhibiting the proliferation of SIVnano in cells.

[0012] Furthermore, the recombinant vector is the psLenti-E2F2-3Flag or pcDNA3.1-E2F2-3Flag plasmid.

[0013] The present invention claims the use of a substance that can promote the expression and / or increase the activity of the following (1) or (2) in at least one of the following (a)-(c):

[0014] (1) E2F2 protein;

[0015] (2) A nucleic acid molecule encoding the E2F2 protein;

[0016] (a) Inhibiting the proliferation of HIV-1 in cells, or preparing a product for inhibiting the proliferation of HIV-1 in cells;

[0017] (b) Inhibiting the proliferation of HIV-2 in cells, or preparing a product for inhibiting the proliferation of HIV-2 in cells;

[0018] (c) Inhibiting the proliferation of SIVnano in cells, or preparing a product for inhibiting the proliferation of SIVnano in cells.

[0019] Furthermore, the substance that promotes the expression and / or increases the activity of (1) or (2) is a recombinant vector containing the nucleic acid molecule, and the recombinant vector is the psLenti-E2F2-3Flag or pcDNA3.1-E2F2-3Flag plasmid.

[0020] Furthermore, the product is a drug or a health product.

[0021] The present invention claims the use of a substance that can inhibit the decrease in the expression and / or activity of the following (1) or (2) in at least one of the following (a)-(c):

[0022] (1) E2F2 protein;

[0023] (2) A nucleic acid molecule encoding the E2F2 protein;

[0024] (a) Promoting the proliferation of HIV-1 in cells, or preparing a product for promoting the proliferation of HIV-1 in cells;

[0025] (b) Promoting the proliferation of HIV-2 in cells, or preparing a product for promoting the proliferation of HIV-2 in cells;

[0026] (c) Promoting the proliferation of SIVnano in cells, or preparing a product for promoting the proliferation of SIVnano in cells.

[0027] Furthermore, the product for promoting the proliferation of HIV-1 in cells is a cell model with enhanced HIV-1 proliferation ability, or a substance for preparing a cell model with enhanced HIV-1 proliferation ability;

[0028] The product for promoting the proliferation of HIV-2 in cells is a cell model with enhanced HIV-2 proliferation ability, or a substance for preparing a cell model with enhanced HIV-2 proliferation ability; the product for promoting the proliferation of SIVnano in cells is a cell model with enhanced SIVnano proliferation ability, or a substance for preparing a cell model with enhanced SIVnano proliferation ability.

[0029] Furthermore, the substance capable of inhibiting the expression and / or activity reduction of (1) or (2) is the shRNA 124068 plasmid for knocking out or reducing the expression of E2F2.

[0030] Furthermore, the E2F2 protein is a protein with the amino acid sequence shown in Sequence 1 of the Sequence Listing.

[0031] The beneficial effects of the present invention are as follows: Overexpression of E2F2 can significantly inhibit HIV-1 infection. This inhibitory effect is independent of the plasmid backbone used, and this inhibitory effect can be stably presented at low to high HIV-1 infection doses. Increasing the expression level of E2F2 can, to a certain extent, improve its ability to inhibit HIV-1 infection, and reducing its expression level can, to a certain extent, promote the ability of HIV-1 infection. E2F2 also has a certain inhibitory ability against other retroviruses such as HIV-2 and SIV. Further findings show that the function of E2F2 in inhibiting HIV-1 is based on its ability to prevent HIV-1 from integrating into the host genome. Overexpression of E2F2 may play an important role in anti-HIV-1 infection and the treatment of HIV carriers. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Inhibitory effect of overexpressed E2F2 on HIV-1 at different infection doses

[0033] Figure 2 Overexpressed E2F2 inhibits the proliferation of HIV-1 in a dose-dependent manner

[0034] Figure 3 Knockdown of E2F2 promotes the proliferation of HIV-1 to a certain extent;

[0035] Figure 4 Inhibitory effect of E2F2 on HIV-2 and SIVnano;

[0036] Figure 5 E2F2 prevents HIV-1 infection by inhibiting virus integration. Detailed implementation manners

[0037] The present invention will be further described in detail below in conjunction with the specific implementation manners. The provided embodiments are only for clarifying the present invention, rather than limiting the scope of the present invention. The following provided embodiments can be used as a guide for those of ordinary skill in the art to make further improvements, and do not constitute any limitation to the present invention in any way.

[0038] The experimental methods in the following embodiments are all conventional methods unless otherwise specified, and are carried out according to the techniques or conditions described in the literature in this field or according to the product specifications. The materials, reagents, etc. used in the following embodiments can be obtained from commercial channels unless otherwise specified.

[0039] Unless otherwise specified, in the following embodiments, quantitative tests are all set with three repeated experiments, and the results are averaged.

[0040] The cells, viruses and plasmids involved in the following embodiments: The 293T cells and TZM-bl cells used in the experiments are both from ATCC. The 293T and TZM-bl cells are respectively cultured in DMEM medium and RPMI1640 medium supplemented with 10% fetal bovine serum and 2% penicillin-streptomycin antibiotic mixture. The plasmids pcDNA3.1-MCS-3Flag and pcDNA3.1-E2F2-3Flag are synthesized by mBio. The plasmids pCD4 and pCXCR4, and the virus strain NL4-3.Luc.VSVG / X4 Env / SIVnano / MLV are from the Laboratory of Biotherapy, China Medical University. The E2F2 shRNA plasmids used are purchased from Horizon Discovery, and the clone IDs are V2LHS_172943, V2LHS_403193, V2LHS_403192, V2LHS_403191, V2LHS_324068 respectively.

[0041] Regarding the animal viruses involved in this application, the public can obtain the biological materials from the applicant in accordance with the relevant regulations on national biosafety. The biological materials are only used for repeating the relevant experiments of the present invention and cannot be used for other purposes.

[0042] The biological reagents involved in the following embodiments: LipoD293 TM Transfection reagent is purchased from SignaGen; lipofectamineTM3000 transfection reagent is purchased from ThermoFisher; luciferase assay kit (Cat.E1500) is purchased from Promega; RNeasy Mini Kit (Cat.74104) is purchased from QIAGEN; PrimeScript TMThe RTreagent Kit with gDNA Eraser (Cat.RR047Q) was purchased from TAKARA; TB Green Premix ExTaq TM Ⅱ (Cat.RR820A) was purchased from TaKaRa, Gibco TM Fetal bovine serum (Cat.10091148) was purchased from ThermoFisher, Hyclone TM Penicillin-streptomycin antibiotic mixture (Cat.SV30010), Hyclone TM RPMI1640 medium (Cat.SH30027.01), Hyclone TM DMEM medium (Cat.SH30243.01) were all purchased from Cytiva

[0043] Focusing on the treatment challenges of HIV latent infection and rebound after drug withdrawal, the research focused on the key factors and mechanisms of host cell regulation of HIV latent infection and rebound after drug withdrawal. In this invention, through the overexpression and silencing of E2F2, it was clarified that E2F2 can inhibit HIV infection

[0044] Example 1 Inhibitory effect of overexpressing E2F2 on HIV-1 with different infection doses

[0045] E2F2 (the coding sequence is as shown in NM_004091.4, encoding a protein with the amino acid sequence as shown in Sequence 1) fused with a 3Flag tag was cloned into the psLenti-3Flag plasmid and the pcDNA3.1-3Flag plasmid to obtain the psLenti-E2F2-3Flag / pcDNA3.1-E2F2-3Flag plasmid

[0046] 1. Construction of overexpression plasmids

[0047] The coding sequence of E2F2 (as shown in NM_004091.4) and the 3Flag tag were used to replace the sequence between the EcoR I site and the XbaI site on the psLenti-3Flag plasmid, and the other sequences remained unchanged, resulting in the plasmid psLenti-E2F2-3Flag

[0048] The coding sequence of E2F2 (as shown in NM_004091.4) was used to replace the sequence between the BamHI site and the AgeI site on the pcDNA3.1-3Flag plasmid, and the other sequences remained unchanged, resulting in the plasmid pcDNA3.1-E2F2-3Flag

[0049] 2. Inhibitory effect of overexpressing E2F2 on HIV-1 with different infection doses

[0050] 18 to 24 hours before transfection, 0.8 - 1×10 6 293T cells were seeded in 6-well plates at a volume of 1 mL per well. For each well, 1.0 μg of pcDNA3.1-E2F2-3Flag / psLenti-E2F2-3Flag / psLenti-3Flag / Mock DNA was diluted into 100 μL of serum-free DMEM pre-warmed at 37°C. Gently vortex to mix; add 3 volumes of plasmid of LipoD293 to each tube; gently vortex to mix; incubate at room temperature for 10 minutes to form the DNA-LipoD293 TM transfection complex; add the LipoD293 / DNA mixture dropwise to the medium in each well, and gently rotate the plate to make the mixture uniform; remove the medium containing the LipoD293 / DNA complex 4 - 6 hours after transfection, and replace it with 1 mL of medium containing full serum / antibiotics pre-warmed at 37°C; 24 hours later, the cells were infected with 1 / 5 / 10 / 25 / 50 / 100 ng p24 equivalent of the NL4-3.Luc(VSV-G) strain thawed at room temperature respectively. After incubation for 24 hours, 300 μL of Passive Lysis Buffer was added, shaken at room temperature for 15 min, mixed with Luciferase Assay Reagent in a ratio of 2:1, and the luciferase value was read on a microplate reader.

[0051] The results are as Figure 1 shown that after transfection with the E2F2 plasmid based on the psLenti backbone, the luciferase values at each HIV infection dose decreased significantly. Similarly, after transfection with 1.0 μg of the E2F2 plasmid based on the pcDNA3.1 backbone, the Luc values at each HIV infection dose decreased significantly, indicating that overexpression of E2F2 strongly inhibits the proliferation of HIV-1 in cells, and its anti-HIV-1 infection effect is independent of the plasmid backbone, but due to its own antiviral function.

[0052] Example 2 is the inhibitory effect of overexpressing different levels of E2F2 on HIV-1

[0053] 18 to 24 hours before transfection, 0.8 - 1×10 6293T cells were plated in a 6-well plate at a volume of 1 mL. At the time of transfection, pcDNA3.1-E2F2-3Flag, psLenti-E2F2-3Flag, psLenti-3Flag, and Mock DNA were each diluted to 100 μL of serum-free DMEM at three doses of 0.5, 1.0, and 1.5 μg. The DMEM was preheated at 37 °C. Gently vortex and mix; add 3 volumes of LipoD293 per volume of plasmid to each tube; gently vortex and mix; incubate at room temperature for 10 minutes to form the DNA-LipoD293 TM transfection complex; add the LipoD293 / DNA mixture dropwise to the medium in each well, and gently rotate the plate to make the mixture uniform; 4 - 6 hours after transfection, remove the medium containing the LipoD293 / DNA complex and replace it with medium containing full serum / antibiotics; 24 hours later, the cells were infected with 100 ng p24 equivalent of the NL4-3.Luc(VSV-G) strain. After incubation for 24 hours, add 300 μL of Passive Lysis Buffer, shake at room temperature for 15 min, mix with Luciferase Assay Reagent in a ratio of 2:1, and read the luciferase value using a microplate reader.

[0054] The results are as Figure 2 shown. After transfection with 1.0 and 2.0 μg of E2F2 plasmid based on the psLenti backbone, the HIV Luc values decreased significantly, by 7.69-fold and 10.80-fold respectively, while the HIV Luc value did not decrease after transfection with 0.5 μg of E2F2 plasmid; similarly, after transfection with 1.0 and 2.0 μg of E2F2 plasmid based on the pcDNA3.1 backbone, the HIV Luc values decreased significantly, by 7.69-fold and 8.03-fold respectively, indicating that overexpression of E2F2 has a strong ability to inhibit the proliferation of HIV-1, and its anti-HIV-1 proliferation effect is independent of the plasmid backbone. At high expression levels, the antiviral function of E2F2 is enhanced to a certain extent.

[0055] Example 3 is that knockdown of E2F2 promotes the proliferation of HIV-1 in cells

[0056] 1. Determine the optimal shRNA:

[0057] Considering that the endogenous level of E2F2 in 293 cells is relatively low, in this example, shRNA was transfected into the gene overexpressing E2F2 to confirm the knockdown efficiency of E2F2.

[0058] 18 to 24 hours before transfection, at 0.8 - 1*10 per well 6293T cells were plated in a 6-well plate at a volume of 1 mL. For each well, 1.5 μg of shRNA and 0.5 μg of F2-3Flag DNA were diluted into 100 μL of serum-free DMEM pre-warmed at 37°C. Vortex gently; add 6 μL of LipoD293 to each tube; vortex gently; incubate at room temperature for 10 minutes to form the DNA-LipoD293 TM transfection complex; add 100 μL of the LipoD293 / DNA mixture dropwise to the medium in each well, and gently rotate the plate to make the mixture uniform; 4-6 hours after transfection, remove the medium containing the LipoD293 / DNA complex and replace it with medium containing full serum / antibiotics; 48 hours later, detect the knockdown efficiency of each candidate shRNA on E2F2 by Western Blot.

[0059] The shRNAs 403191, 403192, 403193, 172943 and the control plasmid shRNA NT (the E2F2 shRNA plasmids corresponding to the clone IDs V2LHS_403191, V2LHS_403192, V2LHS_403193, V2LHS_172943, V2LHS_324068 respectively) were operated according to the above method, and the results are as Figure 3 shown.

[0060] 2. Detection of the weakened ability to resist HIV-1 infection after the expression of E2F2 is weakened:

[0061] 18 to 24 hours before transfection, 0.8 - 1×10 6 293T cells were plated in a 6-well plate at a volume of 1 mL. For each well, 1.0 or 1.5 μg of F2-3Flag and 1.0 or 0.5 μg of shRNA NT / shRNA124068 DNA were diluted into 100 μL of serum-free DMEM pre-warmed at 37°C. Vortex gently; add 6 μL of LipoD293 to each tube; vortex gently; incubate at room temperature for 10 minutes to form the DNA-LipoD293 TMTransfection complex: Gradually add 100 μL of the LipoD293 / DNA mixture dropwise to the medium in each well, and gently rotate the plate to make the mixture uniform. 4 - 6 hours after transfection, remove the medium containing the LipoD293 / DNA complex, and replace it with the medium containing full serum / antibiotics. 24 hours later, the cells were infected with NL4-3.Luc(VSV-G) (1000 ng p24). After incubation for 24 hours, add 300 μL of Passive Lysis Buffer, shake at room temperature for 15 min, mix it with Luciferase Assay Reagent in a ratio of 2:1, and read the luciferase value through a microplate reader.

[0062] The results are as Figure 3 shown. Based on the overexpression of E2F2, the expression levels of E2F2 transfected with the control plasmid shRNA NT and the candidate plasmids shRNA 403191, 403192, 403193, and 172943 were basically the same, indicating that these candidate shRNAs have no function of preventing E2F2 expression; the candidate shRNA 124068 significantly reduced the expression level of E2F2. Therefore, shRNA 124068 was used as the shRNA plasmid in the subsequent HIV-1Luc detection. The results showed that when the ratio of the E2F2 plasmid to the shRNA plasmid was 1:1, compared with the shRNA NT co-transfection group, the HIV-1Luc value of the shRNA124068 co-transfection group decreased to a certain extent; when the ratio of the E2F2 plasmid to the shRNA plasmid was 3:1, compared with the shRNA NT co-transfection group, the HIV-1Luc value of the shRNA 124068 co-transfection group increased to a certain extent; at the same time, compared with the ratio of 1:1, the increase in the HIV-1Luc value of the shRNA NT co-transfection group at a ratio of 3:1 was more obvious, about ~ times. The above results indicate that the anti-HIV-1 ability of E2F2 is positively correlated with its expression level, and shRNA knockdown of E2F2 can promote the proliferation of HIV-1 in cells to a certain extent.

[0063] Example 4 is the inhibitory effect of E2F2 on HIV-2 and SIVnano

[0064] The above research shows the role of E2F2 in HIV-1 proliferation. This part of the research focuses on the role of E2F2 in the proliferation of other retroviruses.

[0065] 18 to 24 hours before transfection, at 0.8 - 1*10 per well 6293T cells were seeded in a 6-well plate at a volume of 1 mL per well. For each well, 0.5 / 1.0 / 2.0 μg of pcDNA3.1-F2-3Flag / Mock DNA was diluted into 100 μL of serum-free DMEM pre-warmed at 37 °C. Vortex gently; add 3 volumes of LipoD293 per volume of plasmid to each tube; vortex gently; incubate at room temperature for 10 minutes to form the DNA-LipoD293 TM transfection complex; add the LipoD293 / DNA mixture dropwise to the medium in each well, and gently rotate the plate to evenly distribute the mixture; 4 - 6 hours after transfection, remove the medium containing the LipoD293 / DNA complex and replace it with medium containing full serum / antibiotics; 24 hours later, the cells were infected with HIV-2-Luc(VSV-G) / SIVnano(VSV-G) (3 mL of virus supernatant per well). After incubation for 24 hours, 300 μL of Passive Lysis Buffer was added, and the mixture was shaken at room temperature for 15 min and mixed with Luciferase Assay Reagent at a ratio of 2:1, and the luciferase value was read by a microplate reader.

[0066] The results are as Figure 4 shown. Overexpression of E2F2 has a certain inhibitory ability against HIV-2 and SIVnano, reducing by 21% - 38% and 7% - 14% respectively, indicating that E2F2 has broad-spectrum antiretroviral ability, but has a significantly stronger inhibitory effect on HIV-1.

[0067] Example 5 is that E2F2 inhibits HIV-1 infection by mediating viral integration.

[0068] 18 to 24 hours before transfection, 0.8 - 1×10 6 293T cells were seeded in a 6-well plate at a volume of 1 mL per well. For each well, 1.0 μg of pcDNA3.1-F2-3Flag / Mock DNA was diluted into 100 μL of serum-free DMEM pre-warmed at 37 °C. Vortex gently; add 3 volumes of LipoD293 per volume of plasmid to each tube; vortex gently; incubate at room temperature for 10 minutes to form the DNA-LipoD293 TMTransfection complex: Gradually add 104 / 106 μL of LipoD293 / DNA mixture drop by drop into the culture medium in each well, and gently rotate the plate to make the mixture uniform; 4 - 6 hours after transfection, remove the culture medium containing LipoD293 / DNA complex, and replace it with the culture medium containing full serum / antibiotics; 24 hours later, the cells are infected with NL4-3.Luc(VSV-G)(10 / 100 ng p24); and extract the cell genome and circular DNA, and detect HIV total cDNA, integrated DNA and 2-LTR by quantitative polymerase chain reaction.

[0069] The results are as Figure 5 shown. Compared with the Mock transfection group, there was no significant difference in total cDNA and 2LTR in the E2F2 overexpression group, indicating that E2F2 does not affect the reverse transcription and nuclear entry processes of HIV-1; on the other hand, overexpression of E2F2 significantly reduced the amount of HIV integrated DNA, indicating that overexpression of E2F2 prevents HIV-1 infection by inhibiting HIV-1 integration.

[0070] In summary, overexpression of E2F2 can significantly inhibit HIV-1 infection. This inhibitory effect is independent of the plasmid backbone used, and this inhibitory effect can be stably presented at low to high HIV-1 infection doses. Increasing the expression level of E2F2 can improve its ability to inhibit HIV-1 infection to a certain extent, and decreasing its expression level can promote the ability of HIV-1 infection to a certain extent. E2F2 also has a certain inhibitory ability against other retroviruses such as HIV-2 and SIV. Further findings show that the function of E2F2 to inhibit HIV-1 is based on its ability to prevent HIV-1 from integrating into the host genome. Overexpression of E2F2 may play an important role in anti-HIV-1 infection and the treatment of HIV carriers.

[0071] The above has described the present invention in detail. For those skilled in the art, without departing from the purpose and scope of the present invention and without unnecessary experiments, the present invention can be implemented within a wide range under equivalent parameters, concentrations and conditions. Although the present invention gives specific embodiments, it should be understood that the present invention can be further improved. In short, according to the principle of the present invention, this application intends to include any changes, uses or improvements to the present invention, including changes made by using conventional techniques known in the art that are outside the scope disclosed in this application. Some basic features can be applied according to the scope of the following appended claims.

Claims

1. Use of any one of the substances shown in (1) to (3) below in at least one of the following (a) to (c): (1) E2F2 protein; (2) a nucleic acid molecule encoding an E2F2 protein; (3) an expression cassette, recombinant vector or transgenic cell containing the nucleic acid molecule; (a) inhibiting HIV-1 proliferation in cells, or preparing a product for inhibiting HIV-1 proliferation in cells; (b) inhibiting HIV-2 proliferation in cells, or preparing a product for inhibiting HIV-2 proliferation in cells; (c) Inhibiting the proliferation of SIVnano in cells, or preparing a product for inhibiting the proliferation of SIVnano in cells.

2. The use according to claim 1, characterized in that: The recombinant vector is a psLenti-E2F2-3Flag or pcDNA3.1-E2F2-3Flag plasmid.

3. Use of a substance capable of promoting the expression and / or activity enhancement of the following (1) or (2) in at least one of the following (a)-(c): (1) E2F2 protein; (2) a nucleic acid molecule encoding E2F2 protein; (a) inhibiting HIV-1 proliferation in cells, or preparing a product for inhibiting HIV-1 proliferation in cells; (b) inhibiting HIV-2 proliferation in cells, or preparing a product for inhibiting HIV-2 proliferation in cells; (c) Inhibiting the proliferation of SIVnano in cells, or preparing a product for inhibiting the proliferation of SIVnano in cells.

4. The use according to claim 3, characterized in that: The substance that promotes the expression and / or activity enhancement of (1) or (2) is a recombinant vector containing the nucleic acid molecule, and the recombinant vector is a psLenti-E2F2-3Flag or pcDNA3.1-E2F2-3Flag plasmid.

5. The use according to any one of claims 1 to 4, characterized in that: The product is a medicine or a health product.

6. Use of a substance capable of inhibiting the expression and / or reducing the activity of (1) or (2) in at least one of the following (a)-(c): (1) E2F2 protein; (2) a nucleic acid molecule encoding E2F2 protein; (a) promoting the proliferation of HIV-1 in cells, or preparing a product for promoting the proliferation of HIV-1 in cells; (b) promoting HIV-2 proliferation in cells, or preparing a product for promoting HIV-2 proliferation in cells; (c) Promoting the proliferation of SIVnano in cells, or preparing a product for promoting the proliferation of SIVnano in cells.

7. The use according to claim 4, characterized in that: The product for promoting HIV-1 proliferation in cells is a cell model with enhanced HIV-1 proliferation ability, or a substance for preparing a cell model with enhanced HIV-1 proliferation ability; The product for promoting HIV-2 proliferation in cells is a cell model with enhanced HIV-2 proliferation ability, or a substance for preparing a cell model with enhanced HIV-2 proliferation ability; the product for promoting SIVnano proliferation in cells is a cell model with enhanced SIVnano proliferation ability, or a substance for preparing a cell model with enhanced SIVnano proliferation ability.

8. The use according to claim 4, characterized in that: The substance capable of inhibiting the expression and / or reducing the activity of (1) or (2) is the shRNA 124068 plasmid for knocking out or reducing the expression of E2F2.

9. The use according to any one of claims 1 to 8, characterized in that: The E2F2 protein is a protein whose amino acid sequence is shown in Sequence 1 in the sequence listing.

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