CN117510631A

CN117510631A - Humanized antibody targeting DR5, chimeric antigen receptor T cell targeting DR5, and preparation method and application thereof

Info

Publication number: CN117510631A
Application number: CN202210932327.7A
Authority: CN
Inventors: 万晓春; 陈倩; 夏蒙; 韩斌; 王坤; 路宏梁; 唐梦燕; 陈琳纯; 陈小娜
Original assignee: Shenzhen Bindebiotech Co ltd
Current assignee: Shenzhen Bindebiotech Co ltd
Priority date: 2022-08-04
Filing date: 2022-08-04
Publication date: 2024-02-06

Abstract

The present application provides a humanized antibody targeting DR5, the humanized antibody targeting DR5 comprising a heavy chain and a light chain, the amino acid sequence of the heavy chain comprising at least one of SEQ ID NOs 1-6, the amino acid sequence of the light chain comprising at least one of SEQ ID NOs 7-12. The humanized antibody targeting DR5 has high activity and high affinity, can be specifically combined with DR5 protein, can generate killing power on tumor cells, and has higher clinical use safety. The application also provides chimeric antigen receptor T cells targeting DR5, and a preparation method and application thereof.

Description

Humanized antibody targeting DR5, chimeric antigen receptor T cell targeting DR5, and preparation method and application thereof

Technical Field

The application relates to the field of medical biology, in particular to a humanized antibody targeting DR5, a chimeric antigen receptor T cell targeting DR5, a preparation method and application thereof.

Background

Cancer has become the source of life threatening to human beings, and the incidence rate is rising, and research finds that tumor necrosis factor related apoptosis inducing ligand (TRAIL) is a member of the tumor necrosis factor superfamily capable of inducing apoptosis. Death receptor 5 (DR5) belongs to the tumor necrosis factor receptor superfamily member (TNFRSF 10B), the cytoplasmic region of which contains the death domain. TRAIL binds to cell surface DR5, inducing apoptosis; and DR5 is highly expressed in cancer but not or lowly expressed in normal cells. Thus, DR5 is considered a target for a variety of tumors. However, most of the antibodies targeting DR5 are murine monoclonal antibodies, and the murine monoclonal antibodies have strong immunogenicity, and can cause human anti-murine antibody reaction, anti-antibody reaction and the like in clinical application, so that the half-life is shortened, the antibodies are easy to remove, the therapeutic effect is weakened, and the patients are seriously and even threatened for life.

Disclosure of Invention

In view of this, the present application provides a humanized antibody targeting DR5, which can specifically bind to DR5 protein, has strong affinity activity to tumors expressing DR5, and has low immunogenicity, thus avoiding the occurrence of human anti-mouse antibody reaction and anti-antibody reaction, improving safety, and being more beneficial to the application thereof.

In a first aspect, the present application provides a humanized antibody targeting DR5, the humanized antibody targeting DR5 comprising a heavy chain and a light chain, the amino acid sequence of the heavy chain comprising at least one of SEQ ID NOS: 1-6 and the amino acid sequence of the light chain comprising at least one of SEQ ID NOS: 7-12.

The humanized antibody targeting DR5 has high activity and high affinity, can be specifically combined with DR5 protein, has strong affinity activity to the solid tumor cells expressing DR5, avoids human anti-mouse antibody reaction and anti-antibody reaction, has higher safety, and is more beneficial to the application of the humanized antibody in the prevention, diagnosis and treatment of tumors.

In a second aspect, the present application provides a chimeric antigen receptor T cell targeting DR5, comprising a chimeric antigen receptor CAR-DR5 targeting DR5, said CAR-DR5 comprising a DR 5-targeting humanized antibody, an extracellular hinge region, a transmembrane region and an intracellular signaling region of the first aspect, linked in sequence.

In a third aspect, the present application provides a method of making a DR 5-targeting chimeric antigen receptor T cell, comprising:

providing a coding gene of a chimeric antigen receptor CAR-DR5 targeting DR5, and inserting the coding gene of the CAR-DR5 into a delivery vector to obtain a recombinant delivery vector, wherein the coding gene of the CAR-DR5 comprises a signal peptide, a humanized antibody targeting DR5, an extracellular hinge region, a transmembrane region and a coding gene of an intracellular signal region which are sequentially connected from a 5 'end to a 3' end;

packaging and transferring the recombinant transfer vector into a host cell to obtain a recombinant lentivirus;

and transfecting the recombinant lentivirus into CD3 positive T lymphocytes to obtain chimeric antigen receptor T cells targeting DR 5.

The preparation method of the DR 5-targeted chimeric antigen receptor T cell is simple and convenient to operate, can prepare the DR 5-targeted chimeric antigen receptor T cell with excellent activity and targeting property, and is beneficial to application.

In a fourth aspect, the present application provides a recombinant vector comprising a gene encoding a humanized antibody targeting DR5 as described in the first aspect, and/or a gene encoding CAR-DR5 in a chimeric antigen receptor T cell targeting DR5 as described in the second aspect.

The recombinant vector provided by the application can stably realize the preservation of the coding gene of the humanized antibody targeting DR5 and/or the coding gene of the CAR-DR5 in the chimeric antigen receptor T cells targeting DR 5.

In a fifth aspect, the present application provides a cell comprising the recombinant vector of the fourth aspect.

The cell provided by the application can stably store the recombinant vector, and is beneficial to the preparation of chimeric antigen receptor T cells targeting DR 5.

In a sixth aspect, the present application provides the humanized antibody targeting DR5 of the first aspect, the chimeric antigen receptor T cell targeting DR5 of the second aspect, the chimeric antigen receptor T cell targeting DR5 prepared by the preparation method of the third aspect, the recombinant vector of the fourth aspect or the use of the cell of the fifth aspect for preparing a medicament for preventing, diagnosing and/or treating a tumor expressing DR 5.

In the application, the humanized antibody targeting DR5, chimeric antigen receptor T cells targeting DR5, recombinant vector and cells provided by the application can play a targeting role on tumors expressing DR5, can kill tumor cells efficiently and specifically, can reduce or avoid immunogenicity, have higher safety performance, and have wide application prospects in the aspects of prevention, diagnosis, treatment and the like of tumors expressing DR 5.

Drawings

FIG. 1 is a SDS-PAGE map of a partially DR 5-targeting humanized antibody prepared in example 1.

Figure 2 is a graph of flow cytometer detection CAR positive T cell ratio results.

FIG. 3 is a graph showing the results of affinity detection of each antibody, wherein (A) the concentration of the antibody is the initial concentration and the results of detection corresponding to 10-fold, 100-fold and 1000-fold dilutions of the initial concentration, (B) the concentration of the antibody is the initial concentration dilution of 10 ⁴ Multiple of 10 ⁵ Multiple of 10 ⁶ Double sum 10 ⁷ The detection result is multiplied.

FIG. 4 is a graph showing the result of detecting DR5-CAR-T cells by an RTCA instrument in vitro killing tumor cells.

FIG. 5 is a graph showing the results of detection of cytokines released from DR5-CAR-T cells, wherein (A) is the result of detection of IFN-gamma and (B) is the result of detection of IL-6.

FIG. 6 shows the results of flow cytometry detection of DR5 expression from Huh7 cells.

FIG. 7 is a graph of the anti-Huh 7 tumor effect of DR5-CAR-T cells in mice, where (A) is tumor weight, (B) is tumor volume, and (C) is mouse body weight.

FIG. 8 shows the results of flow cytometry detection of DR5 expression from HCT116 cells.

FIG. 9 is a graph of the effect of DR5-CAR-T cells on HCT116 tumors in mice.

Detailed Description

The following description is of the preferred embodiments of the present application, and it should be noted that it will be apparent to those skilled in the art that modifications and adaptations can be made without departing from the principles of the present application, and such modifications and adaptations are intended to be comprehended within the scope of the present application.

Because murine antibodies have stronger immunogenicity, they can cause human anti-murine antibody reactions and anti-antibody reactions, so more and more antibodies are humanized, for example, humanized framework regions are adopted to replace murine framework regions, however, the humanized framework regions are selected very much, and after the humanized antibodies are humanized, the amino acid sequence changes change the size, charge, hydrophobicity, spatial conformation, bond energy and the like of peptide chains, and the conformation of antibody complementarity determining regions is affected, so that the activity and affinity of the whole antibody are affected. Accordingly, the present application provides a humanized antibody targeting DR5, the humanized antibody targeting DR5 comprising a heavy chain (VH) comprising at least one of SEQ ID NOs 1-6 and a light chain (VL) comprising at least one of SEQ ID NOs 7-12. That is, the amino acid sequence of the heavy chain includes at least one of the amino acid sequences shown in SEQ ID NO. 1, SEQ ID NO. 2, SEQ ID NO. 3, SEQ ID NO. 4, SEQ ID NO. 5 and SEQ ID NO. 6, and the amino acid sequence of the light chain includes at least one of the amino acid sequences shown in SEQ ID NO. 7, SEQ ID NO. 8, SEQ ID NO. 9, SEQ ID NO. 10, SEQ ID NO. 11 and SEQ ID NO. 12. The antibody provided by the application is a humanized antibody, not only retains the binding capacity of the antibody to an antigen, but also has a contour extremely similar to that of an antibody molecule in a human body, greatly reduces or basically eliminates the immunogenicity of the antibody, avoids the occurrence of human anti-mouse antibody reaction and anti-antibody reaction, has higher safety, has higher activity and affinity compared with a murine antibody, can be specifically combined with DR5 protein, has stronger affinity activity to solid tumor cells expressing DR5, can not be rapidly cleared due to neutralization by the anti-antibody, has higher half-life, and is more beneficial to the application in the aspects of tumor prevention, diagnosis, treatment and the like.

In the present application, the amino acid sequence of the heavy chain of the humanized antibody targeting DR5 comprises at least one of SEQ ID NOS: 1-6 and the amino acid sequence of the light chain comprises at least one of SEQ ID NOS: 7-12. That is, at least one of SEQ ID NOS.1-6 binds to at least one of SEQ ID NOS.7-12 to form a sequence of a humanized antibody targeting DR 5. In one embodiment, the humanized antibody targeting DR5 may be formed by the attachment of a heavy chain shown as SEQ ID NO. 1 to a light chain shown as SEQ ID NO. 7, SEQ ID NO. 8, SEQ ID NO. 9, SEQ ID NO. 10, SEQ ID NO. 11 or SEQ ID NO. 12, or the humanized antibody targeting DR5 may be formed by the attachment of a heavy chain shown as SEQ ID NO. 2 to a light chain shown as SEQ ID NO. 7, SEQ ID NO. 8, SEQ ID NO. 9, SEQ ID NO. 10, SEQ ID NO. 11 or SEQ ID NO. 12, or the humanized antibody targeting DR5 may be formed by the attachment of a heavy chain shown as SEQ ID NO. 3 to a light chain shown as SEQ ID NO. 7, SEQ ID NO. 8, SEQ ID NO. 9, SEQ ID NO. 10, SEQ ID NO. 11 or SEQ ID NO. 12, or the humanized antibody targeting DR5 may be formed by the attachment of a heavy chain shown as SEQ ID NO. 4 to a light chain shown as SEQ ID NO. 7, SEQ ID NO. 8, SEQ ID NO. 9, SEQ ID NO. 10, SEQ ID NO. 11 or SEQ ID NO. 11, or the light chain shown as SEQ ID NO. 11, or SEQ ID NO. 11 may be formed by the attachment of a light chain shown as SEQ ID NO. 11, SEQ ID NO. 11 or SEQ ID NO. 11, or SEQ ID NO. 5.

In the humanized antibody targeting DR5, the amino acid sequence of the heavy chain is SEQ ID NO. 1, and the amino acid sequence of the light chain is SEQ ID NO. 7; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 2 and the light chain has amino acid sequence of SEQ ID No. 7; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID NO. 1 and the light chain has amino acid sequence of SEQ ID NO. 8; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID NO. 2 and the light chain has amino acid sequence of SEQ ID NO. 8; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID NO 3 and the light chain has amino acid sequence of SEQ ID NO 9; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 4 and the light chain has amino acid sequence of SEQ ID No. 9; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 5 and the light chain has amino acid sequence of SEQ ID No. 9; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 6 and the light chain has amino acid sequence of SEQ ID No. 9; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID NO 3 and the light chain has amino acid sequence of SEQ ID NO 10; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 4 and the light chain has amino acid sequence of SEQ ID No. 10; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 5 and the light chain has amino acid sequence of SEQ ID No. 10; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 6 and the light chain has amino acid sequence of SEQ ID No. 10; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID NO 3 and the light chain has amino acid sequence of SEQ ID NO 11; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 4 and the light chain has amino acid sequence of SEQ ID No. 11; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 5 and the light chain has amino acid sequence of SEQ ID No. 11; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 6 and the light chain has amino acid sequence of SEQ ID No. 11; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID NO. 3 and the light chain has amino acid sequence of SEQ ID NO. 12; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 4 and the light chain has amino acid sequence of SEQ ID No. 12; or humanized antibody targeting DR5, the heavy chain has amino acid sequence of SEQ ID No. 5 and the light chain has amino acid sequence of SEQ ID No. 12; or humanized antibody targeting DR5, the heavy chain has the amino acid sequence of SEQ ID No. 6 and the light chain has the amino acid sequence of SEQ ID No. 12. The humanized antibody targeting DR5 has higher activity and affinity, and has wide application prospects in the aspects of tumor prevention, diagnosis, treatment and the like.

In the embodiment of the application, in the humanized antibody targeting DR5, the amino acid sequence of the heavy chain is SEQ ID NO. 4, and the amino acid sequence of the light chain is SEQ ID NO. 9; or the humanized antibody targeting DR5, wherein the amino acid sequence of the heavy chain is SEQ ID NO. 5, and the amino acid sequence of the light chain is SEQ ID NO. 9; or the humanized antibody targeting DR5, wherein the amino acid sequence of the heavy chain is SEQ ID NO. 4, and the amino acid sequence of the light chain is SEQ ID NO. 11; or the humanized antibody targeting DR5, the amino acid sequence of the heavy chain is SEQ ID NO. 6, and the amino acid sequence of the light chain is SEQ ID NO. 11. The humanized antibody targeting DR5 has more excellent activity and affinity, and is more beneficial to the application in the aspects of tumor prevention, diagnosis, treatment and the like.

In an embodiment of the present application, the heavy chain encoding gene comprises at least one of SEQ ID NOS 13-18. That is, the heavy chain-encoding gene includes at least one of the nucleotide sequences shown in SEQ ID NO. 13, SEQ ID NO. 14, SEQ ID NO. 15, SEQ ID NO. 16, SEQ ID NO. 17 and SEQ ID NO. 18. In an embodiment of the present application, the light chain encoding gene comprises at least one of SEQ ID NOS: 19-24. That is, the coding gene of the light chain includes at least one of the nucleotide sequences shown in SEQ ID NO. 19, SEQ ID NO. 20, SEQ ID NO. 21, SEQ ID NO. 22, SEQ ID NO. 23 and SEQ ID NO. 24. Please refer to table 1, which shows the sequence numbers of the heavy chain and the light chain. It will be appreciated that nucleotide sequences having base degeneracy with SEQ ID NO. 13-24, and that the amino acid sequences corresponding to these nucleotide sequences are still the amino acid sequences shown in SEQ ID NO. 1-12, are also within the scope of the present application.

TABLE 1 sequence numbers of heavy and light chains

In embodiments of the present application, the humanized antibodies that target DR5 further comprise a linker peptide (linker) for linking the heavy and light chains. The genes encoding the heavy and light chains are linked by a linking peptide such that the heavy and light chain amino acid sequences are linked post-translationally and form the protein structure of a humanized antibody targeting DR 5. In one embodiment, the amino terminus of the linker peptide is linked to the carboxy terminus of the heavy chain and the carboxy terminus of the linker peptide is linked to the amino terminus of the light chain (VH-linker-VL); that is, the 5 'end of the connecting peptide-encoding gene is connected to the 3' end of the heavy chain-encoding gene, and the 3 'end of the connecting peptide-encoding gene is connected to the 5' end of the light chain-encoding gene. In another embodiment, the amino terminus of the linker peptide is linked to the carboxy terminus of the light chain and the carboxy terminus of the linker peptide is linked to the amino terminus of the heavy chain (VL-linker-VH); that is, the 5 'end of the connecting peptide-encoding gene is connected to the 3' end of the light chain-encoding gene, and the 3 'end of the connecting peptide-encoding gene is connected to the 5' end of the heavy chain-encoding gene. The inventors have found that the present application provides for the tandem sequence of heavy and light chains in a humanized antibody targeting DR5 without affecting the activity and function of the humanized antibody targeting DR 5. In one embodiment of the present application, the amino acid sequence of the linker peptide comprises (GGGGS) n, where n is a positive integer from 2 to 50. In this case, the linking peptide is a flexible chain, which more easily links the heavy and light chains together to form a spatially stable antibody. Wherein n may be, but is not limited to, 2, 3, 4, 5, 8, 10, 12, 15, 17, 20, 30, 40, or 50, etc., wherein G is glycine and S is serine. For example, when n is 3, the amino acid sequence of the connecting peptide includes GGGGSGGGGSGGGGS; when n is 4, the amino acid sequence of the connecting peptide includes GGGGSGGGGSGGGGSGGGGGGS. Further, n is 2-10. In one embodiment, the amino acid sequence of the linker peptide is shown in SEQ ID NO. 25, which is referred to as linker1.

In the present application, humanized antibodies targeting DR5 can be applied to the fields of prevention, diagnosis, and treatment of DR 5-expressing tumors. In particular, the humanized antibodies targeting DR5 can be used in the form of chimeric antigen receptors described herein below, and can also be used as antibody therapeutics, detection drugs, such as antibody drug conjugates, and the like. For example, humanized antibodies targeting DR5 can be used in the preparation of targeted drugs, antibody drug conjugates or multifunctional antibodies that specifically target DR 5-expressing tumor cells, in the preparation of reagents for diagnosing DR 5-expressing tumors, and in the preparation of chimeric antigen receptor-modified immune cells.

The application also provides a chimeric antigen receptor T cell targeting DR5, comprising a chimeric antigen receptor CAR-DR5 targeting DR5, wherein the CAR-DR5 comprises the humanized antibody targeting DR5, an extracellular hinge region, a transmembrane region and an intracellular signal region, which are sequentially connected. In this application, "sequentially linked" is understood to mean that the carboxy terminus of the amino acid sequence of the humanized antibody targeting DR5 is linked to the amino terminus of the amino acid sequence of the extracellular hinge region, which is linked to the amino terminus of the amino acid sequence of the transmembrane region, which is linked to the amino terminus of the amino acid sequence of the intracellular signaling region.

In this application, the extracellular hinge region is used to promote binding of a humanized antibody targeting DR5 to DR5 on a tumor. In embodiments of the present application, the extracellular hinge region comprises at least one of a CD8 a hinge region, a CD28 hinge region, a CD4 hinge region, a CD5 hinge region, a CD134 hinge region, a CD137 hinge region, and an ICOS hinge region. Further, the extracellular hinge region includes a CD8 a hinge region. Still further, the CD 8. Alpha. Hinge region comprises the amino acid sequence shown in SEQ ID NO. 26, and the extracellular hinge region is referred to as CD 8. Alpha. H.

In this application, the transmembrane region is used to immobilize chimeric antigen receptor T cells targeting DR 5. In embodiments of the present application, the transmembrane region includes at least one of the α, β or ζ chains, CD3 epsilon, CD3 zeta, CD4, CD5, CD8, CD9, CD16, CD22, CD28, CD33, CD37, CD45, CD64, CD80, CD86, CD134, CD137, CD152, CD154, and the transmembrane region of PD-1 of the T cell receptor. Further, the transmembrane region includes at least one of the transmembrane regions of CD4, CD8, CD28, CD45, CD154 and PD-1. Still further, the transmembrane region includes at least one of the transmembrane regions of CD8 and CD 28. In one embodiment, the CD8 transmembrane region comprises the amino acid sequence shown in SEQ ID NO. 27, which is referred to as the CD8Tm. In another embodiment, the CD28 transmembrane region comprises the amino acid sequence shown in SEQ ID NO. 28, which is referred to as the CD28Tm.

In this application, intracellular signaling regions are used to signal T cell activation, maintain T cell survival and activate T cell proliferation signaling pathways. In embodiments of the present application, the intracellular signaling region comprises at least one of a costimulatory signaling domain and a signaling domain. Further, the intracellular signal region includes one or more costimulatory signal domains. In one embodiment of the present application, the costimulatory signaling domain comprises at least one of CARD11, CD2, CD7, CD27, CD28, CD30, CD40, CD54, CD83, OX40 (CD 134), 4-1BB (CD 137), CD150, CD152, CD223, CD270, PD-L2, PD-L1, CD278, DAP10, LAT, NKD2C, SLP76, TRIM, fcεRIgamma, myD88, and 41BBL signaling regions. Further, the co-stimulatory signaling domain includes at least one of a CD28, 4-1BB, and OX40 signaling region. Still further, the costimulatory signal domain comprises at least one of a CD28 and a 4-1BB signal region. In one embodiment, the 4-1BB signal region comprises the amino acid sequence shown in SEQ ID NO. 29, and the costimulatory signal domain is designated 4-1BB. In another embodiment, the CD28 signaling region comprises the amino acid sequence set forth in SEQ ID NO. 30, and the costimulatory signaling domain is designated CD28. In another embodiment of the present application, the signaling domain comprises at least one of TCR ζ, fcrγ, fcrβ, cd3γ, cd3δ, cd3ε, CD5, CD22, CD79a, CD79b, CD278 (ICOS), CD66d, and cd3ζ signaling regions. Further, the signaling domain comprises a cd3ζ signaling region. In one embodiment, CD3 zeta comprises the amino acid sequence shown in SEQ ID NO. 31, and the signaling domain is referred to as CD3 zeta. In one embodiment, the intracellular signal region comprises a 4-1BB signal region and a CD3ζ signal region. In another specific embodiment, the intracellular signaling region comprises a CD28 signaling region, a 4-1BB signaling region, and a CD3 zeta signaling region. Wherein the CD3 zeta signal region is the signal transmission domain of T cell, the CD28 signal region and the 4-1BB signal region are used as co-stimulus signals of T cell, and under the combined action of them, the T cell is completely activated after recognizing antigen.

The chimeric antigen receptor T cells targeting DR5 provided by the application have the chimeric antigen receptor targeting DR5, can specifically target tumor cells expressing DR5, activate the T cells to play a role of cell immunity, realize efficient and specific killing on DR5 positive tumor cells, have lasting cell activity and killing power, and hardly cause damage to normal cells; meanwhile, the antibody in the chimeric antigen receptor of the targeting DR5 is a humanized antibody, so that the immunogenicity of the murine antibody is avoided, the occurrence of human anti-murine antibody reaction and anti-antibody reaction can be avoided, and the safety is higher.

The application also provides a preparation method of the chimeric antigen receptor T cell targeting DR5, which comprises the following steps: providing a coding gene of a chimeric antigen receptor CAR-DR5 targeting DR5, and inserting the coding gene of the CAR-DR5 into a delivery vector to obtain a recombinant delivery vector, wherein the coding gene of the CAR-DR5 comprises a signal peptide, the humanized antibody targeting DR5, an extracellular hinge region, a transmembrane region and a coding gene of an intracellular signal region which are sequentially connected from a 5 'end to a 3' end; packaging and transferring the recombinant transfer vector into a host cell to obtain a recombinant lentivirus; and (3) transfecting the recombinant lentivirus into CD3 positive T lymphocytes to obtain chimeric antigen receptor T cells targeting DR 5. In the present application, "sequentially linked from 5 'end to 3' end" is understood to mean that the 3 'end of the coding gene sequence of the signal peptide is linked to the 5' end of the coding gene of the humanized antibody targeting DR5, the 3 'end of the coding gene of the humanized antibody targeting DR5 is linked to the 5' end of the coding gene of the extracellular hinge region, the 3 'end of the coding gene of the extracellular hinge region is linked to the 5' end of the coding gene of the transmembrane region, and the 3 'end of the coding gene of the transmembrane region is linked to the 5' end of the coding gene of the intracellular signal region.

In this application, the signal peptide is used to direct the expression of the chimeric antigen receptor CAR-DR5 to the cell surface, the signal peptide being cleaved by the signal peptidase during protein translational maturation. In embodiments of the present application, the amino acid sequence of the signal peptide comprises the amino acid sequence as set forth in SEQ ID NO:32, and a polypeptide having the amino acid sequence shown in seq id no. Other signal peptide sequences that function similarly can be used for the signal peptide in this application. Specific choices of the extracellular hinge region, the transmembrane region, and the intracellular signal region and corresponding coding gene sequences are as described above, and will not be described in detail herein.

In embodiments of the present application, a start codon (e.g., ATG) may be added to the 5 'end of the coding gene of CAR-DR5 and a stop codon (e.g., TAA) may be added to the 3' end of the coding gene of the chimeric antigen receptor targeting DR5 prior to insertion into a delivery vector. In one embodiment, the delivery vector may be a plasmid vector, such as a pCDH plasmid. The pCDH plasmid can be ligated with elongation factor 1 alpha (EF 1 alpha) as a promoter for transcription of the CAR-DR5 encoding gene.

In an embodiment of the present application, the recombinant transfer vector is packaged and transfected into a host cell to obtain a recombinant lentivirus comprising: and co-transfecting the recombinant transfer vector, the envelope plasmid and the packaging plasmid into a host cell to obtain the recombinant lentivirus. Wherein the host cell is used to assemble the recombinant lentivirus to render it infectious. In one embodiment, the host cells may include HEK293T cells, 293T cells, 293FT cells, SW480 cells, u87MG cells, HOS cells, COS1 cells, COS7 cells, or the like, but are not limited thereto. For example, the host cell may be a HEK293T cell.

In the present application, the recombinant lentivirus can be packaged by a three-plasmid system or a four-plasmid system, and the envelope plasmid and the packaging plasmid are common substances in the field. It will be appreciated that the envelope plasmid, packaging plasmid and plasmids of the gene transfer vector described above are different. In one embodiment, the packaging plasmids are pMDLg/pRRE and pRSV-REV and the envelope plasmid may be pMD2.G. The envelope plasmid may encode a vesicular stomatitis virus glycoprotein (VSV-G) capsid that may assist in adherence of the recombinant lentivirus to the cell membrane and maintain infectivity of the recombinant lentivirus. Envelope plasmids encoding other envelope proteins, such as RD114, baboon retrovirus envelope glycoprotein, measles virus envelope protein, etc., having the properties of also infecting human cells may also be used in the present application.

In embodiments of the present application, the CD3 positive T lymphocytes are isolated from human peripheral blood mononuclear cells. Further, the human peripheral blood mononuclear cells are derived from autologous venous blood, autologous bone marrow, umbilical cord blood, placental blood and the like. Specifically, the human peripheral blood mononuclear cells can be from a cancer patient, and the chimeric antigen receptor T cells prepared by the method can have lower immune response when being returned to the patient; for example, it may be derived from fresh peripheral blood or bone marrow collected one month after a cancer patient's operation and one month after chemoradiotherapy. In one embodiment, the CD3 positive T lymphocytes are obtained as follows: adding CD3/CD28 immunomagnetic beads into peripheral blood mononuclear cells according to a certain proportion, incubating for a period of time, placing into a magnet for screening to obtain CD3 positive T lymphocytes coated with the immunomagnetic beads, and removing the magnetic beads to obtain the CD3 positive T lymphocytes.

Referring to Table 2, the numbers of the CAR-DR5 structures and corresponding DR 5-targeting chimeric antigen receptor T cells (DR 5-CAR-T cells) provided in one embodiment of the present application are shown. It will be appreciated that six CAR-DR5 structures are shown in table 2 by way of example only, and that other connection manners and sequence selections are possible for the CAR-DR5 structures protected herein, and are not described in detail herein.

TABLE 2 CAR-DR5 Structure and corresponding DR5-CAR-T cell numbering

CAR-DR5 structure	DR5-CAR-T cell numbering
		H7-linker1-L6-CD8h-CD8Tm-41BB-CD3ζ	TND3
L6-linker1-H7-CD8h-CD8Tm-41BB-CD3ζ	TND4
		L6-linker1-H7-CD8h-CD28Tm-CD28-41BB-CD3ζ	TND5
L6-linker1-H5-CD8h-CD8Tm-41BB-CD3ζ	TND6
		L4-linker1-H6-CD8h-CD8Tm-41BB-CD3ζ	TND7
L4-linker1-H5-CD8h-CD8Tm-41BB-CD3ζ	TND8

In this application, the chimeric antigen receptor T cells targeting DR5 may also have other expression sequences therein, such as cytokines (IL-12, IL-15, IL-21, type I interferons, etc.), chemokines (CCR 2, CCR5, CXCR2, CXCR4, etc.), safety switches (iCaspase-9, tEGFR, rituximab-CD 34-rituximab, etc.), siRNA that reduces PD-1 expression, proteins that block PD-L1, T cell antigen receptors, chimeric antigen receptors that target other tumor antigens or tumor microenvironment, etc.

The application also provides a recombinant vector comprising the coding gene of the humanized antibody targeting DR5 and/or the coding gene of CAR-DR5 in the chimeric antigen receptor T cells targeting DR 5. The recombinant vector can stably realize the preservation of the coding gene of the humanized antibody targeting DR5 and/or the coding gene of the CAR-DR5 in chimeric antigen receptor T cells targeting DR 5.

In an embodiment of the present application, the vector is at least one of a viral vector and a non-viral vector. Further, non-viral vectors include plasmid vectors and phage vectors. In particular, the plasmid vector may be, but is not limited to, eukaryotic plasmid vectors, prokaryotic plasmid vectors, microcircular DNA, transposons, mRNA, etc. Further, the viral vector includes a lentiviral vector, an adenoviral vector or a retroviral vector. Further, the viral vector is a lentiviral vector. In particular, the viral vector may include, but is not limited to, at least one of a pCDH plasmid, a pWPXLD vector, a pLEX-MCS vector, a pSico vector and a pCgpV vector.

The application also provides a cell comprising the recombinant vector. The cell can stably store the recombinant vector, and is beneficial to the preparation of chimeric antigen receptor T cells targeting DR 5. The application also provides application of the humanized antibody targeting DR5, the chimeric antigen receptor T cell targeting DR5 prepared by the preparation method, the recombinant vector or the cell in preparation of medicines for preventing, diagnosing and/or treating tumors expressing DR 5. The humanized antibody targeting DR5, chimeric antigen receptor T cells targeting DR5, recombinant vector and cells provided by the application can play a targeting role on tumors expressing DR5, and can kill tumor cells efficiently and specifically, thereby realizing prevention, diagnosis, treatment and the like on the tumors expressing DR 5.

In the present application, the DR5 expressing tumor may be, but is not limited to, a solid tumor, such as at least one of colon cancer, gastric cancer, pancreatic cancer, ovarian cancer, breast cancer, non-small cell lung cancer, and the like. Wherein, immune check point inhibitor, targeted therapy, small molecule inhibitor and the like can be adopted in the prevention and treatment of tumors expressing DR5, and the immune check point inhibitor, targeted therapy, small molecule inhibitor and the like can be matched with the humanized antibody targeting DR5, the chimeric antigen receptor T cell targeting DR5, the recombinant vector or the cell prepared by the preparation method.

In the embodiment of the application, the medicine for preventing, diagnosing and/or treating the tumor expressing the DR5 comprises chimeric antigen receptor T cells targeting the DR5, wherein the chimeric antigen receptor T cells targeting the DR5 can be infused into a patient by intravenous injection, subcutaneous injection, tumor in-situ injection and the like, and can achieve good treatment effect.

The humanized antibody targeting DR5 and the chimeric antigen receptor T cell targeting DR5 formed by the humanized antibody targeting DR5 have high affinity to antigen, even better than murine antibody, and have strong killing effect on tumor cells, and obvious tumor inhibition and anti-tumor effects.

The technical scheme and effects of the present application are further described below by means of specific examples.

Example 1

Preparation of a humanized antibody targeting DR5 comprising:

synthesizing nucleotide sequences of heavy chains corresponding to SEQ ID NO. 1-6, and respectively connecting the nucleotide sequences to pAb20-hCHIgG1 vectors to obtain six heavy chain recombinant vectors; synthesizing the nucleotide sequence of the light chain corresponding to SEQ ID NO. 7-12, and respectively connecting the nucleotide sequences to pAb20-hCK vectors to obtain six light chain recombinant vectors; and (3) transfecting HEK293 cells with one of the six heavy chain recombinant vectors and one of the six light chain recombinant vectors together, expressing the humanized antibody targeting DR5, and purifying to obtain the humanized antibody targeting DR 5. SDS-PAGE detection of the obtained humanized antibody targeting DR5, wherein FIG. 1 is a SDS-PAGE diagram of the partially DR 5-targeting humanized antibody prepared in example 1, it can be seen that the humanized antibody targeting DR5 can be obtained by the above-described method; it will be appreciated that, as shown in Table 1, H6L4 in FIG. 1 represents that the heavy chain amino acid sequence of the humanized antibody targeting DR5 is SEQ ID NO. 5, the light chain amino acid sequence is SEQ ID NO. 9, H5L4, H5L6 and H7L6 are similar to those described above, and the details are omitted here, MK being a protein molecular weight standard (marker).

Example 2

A method of making a DR 5-targeted chimeric antigen receptor T cell comprising:

(1) Preparation of gene sequence of chimeric antigen receptor T cell CAR-DR5 targeting DR5

Coding genes of a humanized antibody targeting DR5, a hinge region, a transmembrane region and a signal region are prepared respectively, the coding genes are sequentially connected together from the 5' end to the 3' end by a PCR method to obtain a nucleotide sequence of a CAR-DR5 structure shown in Table 2, and a nucleotide sequence (a gene sequence of a signal peptide) corresponding to an amino acid sequence shown in SEQ ID NO. 31 is added to the 5' end.

(2) Construction of recombinant plasmids

The multiple sets of nucleotide sequences obtained in step (1) were inserted into pCDH vectors, respectively, and located after elongation factor 1α (EF 1 α) of the vectors. When the nucleotide sequence is inserted into the pCDH vector, an initiation codon (ATG) may be added to the 5 '-end of the nucleotide sequence and a termination codon (TAA) may be added to the 3' -end. Then transferring into competent cells DH5 alpha of the escherichia coli, and carrying out positive clone PCR identification and sequencing identification. And (3) successfully constructing the recombinant plasmid by detecting and sequencing the PCR product gel electrophoresis to identify the size and the sequence of the fragment which accords with the purpose.

(3) Recombinant lentivirus construction

And (3) co-transfecting the plurality of groups of recombinant plasmids obtained in the step (2) with packaging plasmids (pMDLg/pRRE and pRSV-REV) and envelope plasmids (pMD 2. G) respectively, and centrifuging after 48 hours to obtain the recombinant lentivirus.

(4) Preparation of chimeric antigen receptor T cells targeting DR5

Drawing 30ml-100ml of patient blood, and sending the sample to a blood separation chamber; collecting peripheral blood mononuclear cells, and taking middle-layer cells after Ficoll centrifugal separation; after washing with PBS, PBMC were obtained. Adding a basic culture medium without serum into the PBMC to prepare cell suspension; adding anti-CD 3/anti-CD 28 immunomagnetic beads according to the ratio of the magnetic beads to the cells being 3:1, and incubating for 1h at room temperature; screening cells incubated with the magnetic beads by using a magnet; the CD3 positive T lymphocytes containing the magnetic beads are obtained. Re-suspending cells with culture medium, culturing in incubator for 1 day, collecting T lymphocytes, adding recombinant lentivirus with virus infection complex (MOI) of 5, co-culturing, and isolating 500g after 48 hrVirus supernatant was removed at heart 6min and T cell pellet was resuspended in fresh medium and culture continued. After the cells were cultured until day 8-14, the magnetic beads were removed by a magnet, and centrifuged at 500g for 8min to obtain chimeric antigen receptor T cells targeting DR5 (DR 5-CAR-T cells). Taking 1×10 ⁶ Cells were incubated with 1 μl DR5 protein at 4deg.C for 30min in the absence of light, then washed with 1ml Du's Phosphate Buffer (DPBS), centrifuged at 300g for 5min, and the supernatant removed and resuspended in 100 μl DPBS+2% Fetal Bovine Serum (FBS). Mu.l of CD3 antibody and 0.5. Mu.l of phycoerythrin-labeled streptavidin (PE-streptavidin) were added to each tube, and incubated at 4℃for 30min in the absence of light. After washing with 1ml of DPBS and resuspension of 200 μl of DPBS, the positive rate of DR5-CAR-T cells obtained was examined by flow cytometry, using T cells (UTD) not infected with virus only stimulated by magnetic beads as a control, wherein FIG. 2 is a graph of results of flow cytometry for detection of CAR positive T cell rate, and Table 3 is a corresponding positive rate, indicating that chimeric antigen receptor T cells targeting DR5 were successfully produced, which were stored in a cell cryopreservation solution dedicated for reinfusion.

TABLE 3 Positive rate

DR5-CAR-T cell numbering	Positive rate (%)
		TND3	38.8
TND4	45.1
		TND5	43.8
TND6	39.9
		TND7	57.8
TND8	44.3
		UTD	0.18

To evaluate the effect of the humanized antibodies targeting DR5 and chimeric antigen receptor T cells targeting DR5 prepared by the above methods described herein, the following experiments were performed.

Providing a plurality of groups of DR5 antigens (DR 5/TRAIL R2 Protein, human, his Tag; product number: 10465-H08H, yiqiao Shenzhou Co.) coated with 5 μg/ml, blocking with 5% skimmed milk powder solution, adding antibodies with different concentrations (initial concentration of antibody 0.2 mg/ml) into each group, performing three groups of parallel experiments, wherein humanized antibodies targeting DR5 prepared in example 1 are added as experimental groups, and murine antibodies (H1L 1) targeting DR5 and non-added antibodies (blank) in CN201711166864.0 are used as control groups; then adding corresponding secondary antibodies into each group, measuring OD value by competition ELISA method to obtain affinity detection result of each antibody, as shown in figure 3, taking OD value of blank group as unit "1" and ratio of OD value of each experimental group to OD value of blank group as detection result, wherein (A) the concentration of antibody is initial concentration and detection result corresponding to 10 times, 100 times and 1000 times of initial concentration dilution, and (B) the concentration of antibody is initial concentration dilution 10 ⁴ Multiple of 10 ⁵ Multiple of 10 ⁶ Double sum 10 ⁷ Multiple corresponding detection results, and (A) the columnar detection results of each antibody are the initial concentration, the initial concentration dilution 10 times, 100 times and 1000 times, and (B) the columnar detection results of each antibody are the initial concentration dilution 10 times ⁴ Multiple of 10 ⁵ Multiple of 10 ⁶ Double sum 10 ⁷ A result corresponding to the multiple; it can be seen thatCompared with the murine target DR5 antibody (H1L 1), the humanized antibody targeting DR5 has no reduced affinity, even has much better affinity than H1L1 group, which shows that the humanized antibody targeting DR5 has excellent affinity activity, can avoid immunogenicity of the murine antibody, and has considerable application prospect.

Multiple sets of Anti-hFc probes were provided, each with the antibodies in the protein information shown in Table 4, and with H1L1 as a control, and further with different concentrations of DR5 antigen (37 nM, 111nM, 333nM, 1000 nM), the affinities were determined by Gator apparatus, and the results are shown in Table 5. It can be seen that the affinity of H5L4, H6L4, H5L6 and H7L6 with antigen is far higher than that of H1L1 with antigen, further demonstrating that the humanized antibodies targeting DR5 provided by the present application have excellent affinity activity.

TABLE 4 protein information

TABLE 5 affinity assay results

Antibody-antigen	Full R ²	Kon(1/Ms)	Koff(1/Ms)	KD(M)
					H5L4→DR5	0.996	2.30×10 ⁴	4.83×10 ^-4	2.10×10 ^-8
H6L4→DR5	0.998	2.06×10 ⁴	4.45×10 ^-4	2.16×10 ^-8
					H5L6→DR5	0.997	2.07×10 ⁴	3.53×10 ^-4	1.70×10 ^-8
H7L6→DR5	0.994	3.03×10 ⁴	3.55×10 ^-4	1.17×10 ^-8
					H1L1→DR5	0.992	2.91×10 ⁴	1.00×10 ^-3	3.45×10 ^-8

In vitro tumor cell killing experiments were performed using a real-time cell analyzer (xCElligence RTCA SP). Complete medium containing 8000 Huh7 cells was added to the E-Plate well for culture, which was first matched to the instrument. After about 24h, a corresponding number of DR 5-targeting chimeric antigen receptor T cells prepared by the above preparation method were added at an effective target ratio (E: T) of 10:1, and incubated for a period (> 24 h) with simple medium (blank) with non-virus-infected T cells stimulated with magnetic beads alone (UTD) as control. Analyzing the cell killing effect according to a Cell Index (CI) value of a real-time cell analyzer to obtain a DR5-CAR-T cell in-vitro tumor cell killing result, as shown in FIG. 4; meanwhile, the same operation is performed at the effective target ratio of 5:1, cell culture supernatant is taken after co-culture for 24 hours, and the Cytokine level released by DR5-CAR-T cells (CBA Human Th1/Th2 Cytokine Kit II, BD company) is detected, as shown in FIG. 5, wherein (A) is the detection result of gamma interferon (IFN-gamma), and (B) is the detection result of interleukin-6 (IL-6). It can be seen that the chimeric antigen receptor T cells targeting DR5 provided by the application have very strong killing effect on tumor cells, and the killing capacity is far higher than that of a blank group and a UTD group, and a large amount of cytokines are secreted.

Subcutaneous inoculation of 11 6-week-old B-NDG female mice with Huh7-Luciferase-GFP cells 0.2 ml/mouse (1.6X10) ⁶ Cells), and after 1 week of inoculation, were divided into 3 groups, and UTD cells (magnetic bead-stimulated only, non-virally infected T cell control), TND4 cells, and TND5 cells (4X 10) ⁶ DR 5-CAR-T/one), the total number of T cells injected by UTD group is the same as the number of T cells injected by TND group, and the number of animals in each group is 3, 4, respectively. The inoculated Huh7 cells were subjected to flow cytometry detection and DR5Antibody staining (PE anti-human DR5 anti-body (bioleged, 307405)) ("1") was performed, while isotype control (PE Mouse lgG1, kappa isotype control Antibody (bioleged, 400111)) ("2") and blank control ("3") staining were performed, as shown in fig. 6, for DR5 expression results of Huh7 cells detected by flow cytometry, it can be seen that the DR5Antibody staining curves were significantly shifted to the right relative to isotype control and blank control, indicating that the inoculated Huh7 liver cancer cells expressed DR5. Tumor size was measured by vernier caliper, weighed and the survival of mice was observed, and the average tumor size in UTD group was approximately 2000mm ³ At this time, the mice were euthanized, tumors were isolated and weighedTumor volume = 1/2× (long diameter) × (short diameter), as shown in figure 7, which is a graph of DR5-CAR-T cell anti-Huh 7 tumor effect in mice, where (a) is tumor weight, (B) is tumor volume, (C) is mouse weight; it can be seen that the DR5-CAR-T cell composed of the humanized antibody targeting DR5 provided by the application can obviously inhibit the growth of tumors in mice, has obvious anti-tumor effect, and has obvious anti-tumor effect when one or a plurality of co-stimulatory signal domains are contained in the CAR-DR5 structure of the DR5-CAR-T cell.

4 6-week-old B-NDG female mice were subcutaneously inoculated with 0.2 ml/mouse HCT116 cells (containing 5X 10) ⁶ Cells), 2 groups after 11 days of inoculation, UTD cells and TND6 cells (5X 10) were administered respectively ⁶ DR 5-CAR-T/one), the total number of T cells injected by UTD group was the same as the number of T cells injected by TND group, 2 animals per group. Flow cytometry detection of inoculated HCT116 cells stained with DR5 antibody ("1"), isotype control ("2") and placebo ("3"), respectively, as shown in fig. 8, it can be seen that the DR5 antibody staining curves were significantly shifted to the right relative to isotype control and placebo, indicating that inoculated HCT116 colorectal cancer cells expressed DR5. Tumor size was measured using vernier calipers, weighed and the survival of mice was observed, tumor volume = 1/2× (long diameter) × (short diameter), as shown in fig. 9, which is a graph of DR5-CAR-T cell anti-HCT 116 tumor effect in mice; it can be seen that TND6 cells can obviously inhibit the growth of tumors in mice, can eliminate large tumors into small tumors, and has obvious anti-tumor effect. Therefore, DR5-CAR-T cells composed of humanized antibodies of different sequences of targeting DR5 provided by the application all have remarkable in vivo anti-tumor effects.

The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the present application. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims

1. A humanized antibody targeting DR5, wherein the humanized antibody targeting DR5 comprises a heavy chain and a light chain, the amino acid sequence of the heavy chain comprising at least one of SEQ ID NOs 1-6, and the amino acid sequence of the light chain comprising at least one of SEQ ID NOs 7-12.

2. The DR 5-targeting humanized antibody of claim 1, wherein the amino acid sequence of the heavy chain is SEQ ID No. 1 and the amino acid sequence of the light chain is SEQ ID No. 7; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 2, and the amino acid sequence of the light chain is SEQ ID NO. 7; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 1, and the amino acid sequence of the light chain is SEQ ID NO. 8; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 2, and the amino acid sequence of the light chain is SEQ ID NO. 8; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 3, and the amino acid sequence of the light chain is SEQ ID NO. 9; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 4, and the amino acid sequence of the light chain is SEQ ID NO. 9; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 5, and the amino acid sequence of the light chain is SEQ ID NO. 9; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 6, and the amino acid sequence of the light chain is SEQ ID NO. 9; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 3, and the amino acid sequence of the light chain is SEQ ID NO. 10; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 4, and the amino acid sequence of the light chain is SEQ ID NO. 10; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 5, and the amino acid sequence of the light chain is SEQ ID NO. 10; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 6, and the amino acid sequence of the light chain is SEQ ID NO. 10; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 3, and the amino acid sequence of the light chain is SEQ ID NO. 11; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 4, and the amino acid sequence of the light chain is SEQ ID NO. 11; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 5, and the amino acid sequence of the light chain is SEQ ID NO. 11; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 6, and the amino acid sequence of the light chain is SEQ ID NO. 11; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 3, and the amino acid sequence of the light chain is SEQ ID NO. 12; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 4, and the amino acid sequence of the light chain is SEQ ID NO. 12; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 5, and the amino acid sequence of the light chain is SEQ ID NO. 12; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 6, and the amino acid sequence of the light chain is SEQ ID NO. 12.

3. The DR 5-targeting humanized antibody of claim 2, wherein the amino acid sequence of the heavy chain is SEQ ID No. 4 and the amino acid sequence of the light chain is SEQ ID No. 9; or (b)

The amino acid sequence of the heavy chain is SEQ ID NO. 6, and the amino acid sequence of the light chain is SEQ ID NO. 11.

4. The humanized antibody of claim 1, wherein the heavy chain encoding gene comprises at least one of SEQ ID NOs 13-18 and the light chain encoding gene comprises at least one of SEQ ID NOs 19-24.

5. The DR 5-targeting humanized antibody of claim 1, further comprising a linker peptide for linking the heavy chain and the light chain, wherein the amino acid sequence of the linker peptide comprises (GGGGS) n, n being a positive integer from 2 to 50.

6. A chimeric antigen receptor T cell targeting DR5 comprising a chimeric antigen receptor CAR-DR5 targeting DR5, said CAR-DR5 comprising, in sequential order, a humanized DR 5-targeting antibody of any one of claims 1-5, an extracellular hinge region, a transmembrane region and an intracellular signaling region.

7. A method of making a DR 5-targeting chimeric antigen receptor T cell comprising:

providing a coding gene of a chimeric antigen receptor CAR-DR5 targeting DR5, inserting the coding gene of the CAR-DR5 into a delivery vector to obtain a recombinant delivery vector, wherein the coding gene of the CAR-DR5 comprises a signal peptide, the humanized antibody targeting DR5, an extracellular hinge region, a transmembrane region and a coding gene of an intracellular signal region according to any one of claims 1-5, which are sequentially connected from 5 'end to 3' end;

8. A recombinant vector comprising a gene encoding the DR 5-targeting humanized antibody of any one of claims 1-5 and/or a gene encoding CAR-DR5 in the DR 5-targeting chimeric antigen receptor T cell of claim 6.

9. A cell comprising the recombinant vector of claim 8.

10. Use of the DR 5-targeting humanized antibody of any one of claims 1-5, the DR 5-targeting chimeric antigen receptor T cell of claim 6, the DR 5-targeting chimeric antigen receptor T cell prepared by the preparation method of claim 7, the recombinant vector of claim 8 or the cell of claim 9 for the preparation of a medicament for preventing, diagnosing and/or treating a DR 5-expressing tumor.