Immortalized T cell line SZ906 derived from peripheral blood of hematoma patient as well as preparation method and application of immortalized T cell line SZ906

Abstract

The invention provides an immortalized T cell line SZ906 derived from peripheral blood of a hematoma patient as well as a preparation method and application of the immortalized T cell line SZ906. The immortalized T cell line SZ906 derived from the peripheral blood of the hematoma patient is preserved in Guangdong Microbial Culture Collection Center on December 25, 2025, and the preservation number is GDMCC No: 67533. The immortalized T cell line SZ906 derived from the peripheral blood of the hematoma patient, provided by the invention, can still keep good multiplication capacity and high survival rate in a long-time (more than one year) culture process, has strong cytotoxicity to tumor cells, and can kill the tumor cells and remove cells infected by pathogens.

Description

Technical Field

[0001] This invention relates to the field of immortalized cell technology, specifically to an immortalized T cell line SZ906 derived from peripheral blood of patients with hematologic malignancies, its preparation method, and its application. Background Technology

[0002] T cells, also known as T lymphocytes, mainly originate from pluripotent stem cells in the bone marrow (or from the yolk sac and liver during the embryonic period). During the embryonic and early life stages, some pluripotent stem cells or pre-T cells in the bone marrow migrate to the thymus and differentiate and mature under the induction of thymic hormones, becoming immune-active T cells.

[0003] T cells are the core executors of the adaptive immune system, playing an irreplaceable role in the body's defense against pathogen infection, elimination of tumor cells, and maintenance of immune homeostasis. These biological characteristics make T cells a promising candidate for immunotherapy, especially for the treatment of malignant tumors, which has become one of the hot topics in current biomedical research and development.

[0004] Currently, T cells commonly used in clinical research or trials mainly originate from peripheral blood, umbilical cord blood, induced pluripotent stem cells, and T cell lines. While peripheral blood is a potential source of T cells, and although it has relatively low immunogenicity and is abundant, primary peripheral blood T cells suffer from poor proliferation and continuous passage stability in vitro. Furthermore, they are prone to functional decline (e.g., decreased ability to kill tumor cells or viruses) with prolonged culture time, making it difficult to meet the stringent requirements for T cell quantity and function in large-scale, standardized immunotherapy. Therefore, there is an urgent need to find a T cell line that can maintain good proliferative capacity, high survival rate, and continuous passage stability during long-term culture, while also possessing high killing ability against tumor cells or viruses. Summary of the Invention

[0005] To address the issues of poor proliferation or continuous passage stability of existing peripheral blood-derived T cells in vitro, and their tendency to experience functional decline with prolonged culture time, this invention provides an immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies patients, along with its preparation method and applications.

[0006] According to a first aspect of the present invention, an immortalized T cell line SZ906 derived from peripheral blood of a hematologic malignancy patient is provided, which was deposited at the Guangdong Provincial Center for Microbial Culture Collection on December 25, 2025, with accession number GDMCC No: 67533.

[0007] Cell immortalization refers to the process by which cultured cells escape the crisis of proliferation and aging due to their own changes or the influence of external conditions, thereby gaining unlimited proliferative capacity. The probability of spontaneous cell immortalization is very low. The construction of immortalized cell lines mainly adopts exogenous induction methods, including chemical substances, radiation mutagenesis, viral infection, telomerase activation, etc.

[0008] The inventors of this application isolated peripheral blood mononuclear cells (PBMCs) from the peripheral blood of patients with hematologic malignancies, and then used STEMdiff... TM Peripheral blood T cells were expanded from PBMCs using a T cell kit. These T cells were then cultured long-term in serum-free cell culture medium supplemented with ALyS505NK-EX containing 500-2000 U / mL IL-2 until significant cell growth was observed. A new immortalized T cell line was obtained and named SZ906. Its classification name is... Homo sapiens SZ906 fine Cell Latin name T lymphocyte cell SZ906 This invention relates to the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies. This immortalized T cell line SZ906 was deposited on December 25, 2025, at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at the Institute of Microbiology, Guangdong Academy of Sciences, 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, with accession number GDMCC No: 67533. The immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies provided by this invention maintains good proliferation capacity and high survival rate even during long-term culture (over one year), and exhibits strong cytotoxicity against tumor cells, capable of killing tumor cells and clearing cells infected by pathogens.

[0009] Preferably, the immortalized T cell line SZ906 is prepared through the following steps: S1. Peripheral blood mononuclear cells were isolated from the peripheral blood of patients with hematologic malignancies; S2.Use STEMdiff TM The T cell kit was used to culture peripheral blood mononuclear cells to obtain peripheral blood T cells; S3. Peripheral blood T cells were further cultured using T cell culture medium to obtain the immortalized T cell line SZ906; The T cell culture medium includes the following components: 500~2000 U / mL IL-2 and basal culture medium.

[0010] Preferably, in S3, the basal culture medium is ALyS505NK-EX serum-free NK cell culture medium.

[0011] Preferably, S3 includes the following steps: culturing peripheral blood T cells in T cell culture medium for 3-7 days, and adding the T cell culture medium to the culture system to adjust the cell density to (0.5-2.5) × 10⁻⁶ cells / day. 6 Cells / mL were cultured until significant cell growth was observed, resulting in the immortalized T cell line SZ906.

[0012] According to a second aspect of the present invention, the use of the immortalized T cell line SZ906 derived from peripheral blood of patients with hematologic malignancies is provided in the preparation of antitumor drugs.

[0013] The immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies provided by this invention exhibits strong cytotoxicity against tumor cells, capable of killing tumor cells and clearing cells infected by pathogens. When applied to the preparation of antitumor drugs, the resulting antitumor drugs possess strong tumor-killing capabilities and have broad application prospects in the clinical treatment of tumors. Furthermore, the immortalized T cell line SZ906 provided by this invention has good safety and will not pose a risk of tumorigenesis during clinical application.

[0014] Preferably, the tumors mentioned above include ovarian cancer.

[0015] According to a third aspect of the present invention, an antitumor pharmaceutical composition is provided, the antitumor pharmaceutical composition comprising the immortalized T cell line SZ906 derived from the peripheral blood of the aforementioned hematologic malignancy patient.

[0016] Preferably, the tumors mentioned above include ovarian cancer.

[0017] According to a fourth aspect of the present invention, an antitumor pharmaceutical composition is provided, the antitumor pharmaceutical composition containing CAR-T cells constructed by gene editing based on the immortalized T cell line SZ906 derived from the peripheral blood of the above-mentioned hematologic malignancy patients.

[0018] Preferably, the tumors mentioned above include ovarian cancer. Attached Figure Description

[0019] Figure 1 The figure shows the results of observing the T cell status during the culture of peripheral blood T cells using T cell culture medium in step (2) of the preparation step (2) of the immortalized T cell line SZ906 derived from peripheral blood of patients with hematologic malignancies in Example 1, which is a test example.

[0020] Figure 2 The image shows the cell cycle detection results during the long-term culture of the immortalized T cell line SZ906 derived from the peripheral blood of a hematologic malignancy patient, as in Example 1.

[0021] Figure 3STR typing profile of immortalized T cell line SZ906 derived from peripheral blood of a hematologic malignancy patient provided for test example 2.

[0022] Figure 4 The flow cytometry results of the surface markers CD3, CD4, and CD8 of the immortalized T cell line SZ906 derived from peripheral blood of a hematologic malignancy patient provided for test example 3.

[0023] Figure 5 The image shows the soft agar tumorigenesis test results of the immortalized T cell line SZ906 derived from the peripheral blood of a hematologic malignancy patient provided in test example 4.

[0024] Figure 6 The figure shows the experimental results of the killing effect of the immortalized T cell line SZ906 derived from the peripheral blood of a hematologic malignancy patient provided in Example 5 on ovarian cancer cells. Detailed Implementation

[0025] The technical features of the technical solution provided by the present invention will be further clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1 An immortalized T cell line SZ906 derived from peripheral blood of a hematologic malignancy patient, obtained through the following steps: (1) Cell cryopreservation Peripheral blood mononuclear cells (PBMCs) were isolated from peripheral blood of patients with hematologic malignancies using density gradient centrifugation, and the cell density was adjusted to approximately 5 × 10⁻⁶. 6 One live cell / mL, add 1 mL / tube to cryopreservation tube for cryopreservation; (2) Cell resuscitation and culture Using STEMdiff TM Using the T-cell kit (STEMCELL Technologies Inc., catalog number: 10971), culturate frozen PBMCs to day 14 according to the kit instructions, then continue culturing in T-cell medium to day 19. Collect cells and cryopreserve them; thaw one tube of cells cultured to day 19 and adjust the cell density to 2 × 10⁻⁶. 6A cell suspension was obtained by collecting 100 live cells / mL and then inoculating it into T cell culture medium. The medium was then replaced with fresh T cell culture medium every 2-3 days until significant cell growth was observed. This yielded an immortalized T cell line derived from the peripheral blood of hematological malignancy patients, named SZ906, and classified as follows: Homo sapiens SZ906 cells Latin name T lymphocyte cell SZ906 The immortalized T cell line SZ906 derived from the peripheral blood of the hematologic malignancy patient was deposited on December 25, 2025 at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at the Institute of Microbiology, Guangdong Academy of Sciences, 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, with accession number GDMCC No: 67533. The T cell culture medium includes the following components: 1000 U / mL IL-2, ALyS505NK-EX serum-free NK cell culture medium (Zhuhai Beso Cell Science and Technology Co., Ltd., catalog number: 01400P10).

[0027] Test Example 1 This test case aims to observe the cell status during the culture of peripheral blood T cells using T cell culture medium in step (2) of the preparation of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients in Example 1. The results are as follows: Figure 1 As shown, where, Figure 1 Figure 1 shows the cell status observation results of peripheral blood T cells cultured in T cell culture medium for days 28, 133, 254, and 436, respectively.

[0028] Depend on Figure 1 It can be seen that in step (2) of the preparation method provided in Example 1, the culture of peripheral blood T cells using T cell culture medium until day 28 is still a process of immortalization of T cells, during which the cells only grow slightly ( Figure 1 In section A), culturing peripheral blood T cells in T cell culture medium to days 133, 254, and 436 represents the process after successful T cell immortalization (i.e., the T cells at this point are the immortalized T cell line SZ906 obtained in Example 1). During this process, significant cell growth was observed. The number of cells cultured in T cell culture medium to day 133 was significantly higher than that on day 28. Furthermore, the immortalized T cells (i.e., the immortalized T cell line SZ906 obtained in Example 1) remained in good condition and could continue to be cultured at days 133, 254, and 436. This indicates that the immortalized T cell line SZ906 can maintain good proliferative capacity and high survival rate even during long-term (over 1 year) culture.

[0029] Furthermore, this test case also detected the cell cycle of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients obtained in Example 1. The proliferation or continuous passage ability of the immortalized T cell line SZ906 was evaluated in conjunction with the above results. The results are as follows: Figure 2 As shown.

[0030] Depend on Figure 2 It can be seen that the cell cycle 2N (G0 / G1) ratio of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies obtained in Example 1 was 39.3%, which was much lower than the ratio of normal primary cells (70%-85%). This indicates that the G1 phase of the immortalized T cell line SZ906 was significantly shortened and the density inhibition was weakened, with a large number of cells continuously in the growth and expansion cycle.

[0031] Furthermore, during the long-term culture of the T cell line SZ906, the T cell line SZ906, which has been cultured for more than one year, can still grow and proliferate normally.

[0032] The above results prove that the T cell line SZ906 has achieved immortalization.

[0033] In addition, this test case also tested the continuous passage stability of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies obtained in Example 1. The surface markers CD3, CD4, and CD8 of the immortalized T cell line SZ906 were detected at passaged culture days 178, 230, 282, and 518. The results are shown in Table 1.

[0034] Table 1. Detection results of surface markers CD3, CD4, and CD8 during passage culture of the immortalized T cell line SZ906.

[0035] As shown in Table 1, the positive rates of cell surface markers CD3, CD4 and CD8 in the immortalized T cell line SZ906 were similar during continuous culture, and the cell surface markers at D518 were still similar to those at D178.

[0036] The above results demonstrate that the expression of cell surface markers in the T cell line SZ906 exhibits a certain degree of stability during continuous culture.

[0037] Test Example 2 STR loci consist of short tandem repeats of 3–7 base pairs in length. These repeats are widely distributed throughout the human genome, serving as highly polymorphic markers and can be detected by PCR (polymerase chain reaction). Alleles at STR loci can be distinguished by differences in the copy number of repeat sequences within the amplified region, and can be identified by fluorescence detection after separation by capillary electrophoresis. Subsequently, using specific calculation methods, the obtained STR typing results can be compared with a professional cell STR database to infer the cell line to which the sample belongs or the name of any potentially cross-contaminated cell lines.

[0038] This test case aims to identify the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients obtained in Example 1 using STR typing technology, in order to determine whether it is contaminated by human cell lines and the names of cell lines that may be cross-contaminated. The specific experimental procedures are as follows: The whole genome DNA of the immortalized T cell line derived from peripheral blood of hematologic malignancy patients was extracted using a genomic extraction kit. The extracted whole genome DNA sample was numbered as S25120519008. The DNA concentration was detected by QC using a micro UV-Vis spectrophotometer (Thermo Fisher NanoDrop 2000c). At the same time, multiplex amplification using IGE-STR20A (ABI9700 PCR System) was performed. Capillary electrophoresis and fragment separation were performed using an ABI3730XL genetic analyzer (ABI Corporation, USA), and genotyping was performed using GeneMapper® ID software (version: ID-X 1.5).

[0039] The STR typing profile of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients obtained in Example 1 is as follows: Figure 3 As shown in Table 2, the STR genotyping results are as follows. Among them, 8 core STR loci (vWA, D7S820, CSF1PO, D16S539, TH01, D13S317, TPOX, D5S818) and 1 sex locus (Amelogenin) are required to be tested according to the US National Standard (ASN-0002-2011).

[0040] Table 2. STR genotyping results of immortalized T cell line SZ906

[0041] Depend on Figure 3As shown in Table 2, after extracting the whole genome DNA (sample number S25120519008) of the immortalized T cell line SZ906 derived from the peripheral blood of hematologic malignancy patients obtained in Example 1, and testing S25120519008, it was found that no site among the 21 STR loci tested had more than two allele peaks. The above results indicate that the tested sample was not contaminated by human cell lines.

[0042] According to the US National Standard ASN-0002-2011, a cell line with a matching rate of not less than 80% may be the cell line to which the tested cell belongs, or a derivative of that cell line, or it may originate from the same donor as that cell line; a cell line with a matching rate of less than 56% is generally considered to be unrelated to the tested cell; and a cell line with a matching rate between 56% and 80% requires further study to confirm its identity.

[0043] This test case also compared the immortalized T cell line SZ09 derived from peripheral blood of hematologic malignancy patients obtained in Example 1 with cell lines in the Aiji Bio Cell Line Identification Database. The results are shown in Table 3. Table 3 lists the 5 cell lines in the database with the highest percent match rate with the immortalized T cell line SZ906.

[0044] Table 3. Comparison results of immortalized T cell line SZ906 with the Aiji Biotechnology cell line identification database.

[0045] As shown in Table 3, the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients obtained in Example 1 is not a cell line included in the database, nor is it included in any cell bank. It is a new T cell line.

[0046] Test Example 3 Helper T cells (CD3) + CD4 + CD8 - The main function of B cells is to assist other immune cells in their function. They regulate the immune response by secreting cytokines, for example, by promoting the proliferation and differentiation of B cells, thereby enhancing the humoral immune response. B cells are involved in CD4+ immune responses. + With the help of T cells, antibodies can be produced more effectively. Antibodies can recognize and neutralize pathogens. They can also activate macrophages, enhancing their phagocytic and bactericidal abilities. After macrophages engulf pathogens, they present some antigenic information of the pathogens to CD4 cells. + T cells, CD4 +After recognizing these antigens, T cells secrete cytokines to stimulate macrophages, enabling them to more effectively perform phagocytosis and bactericidal functions; they can also participate in cell-mediated immune responses, promoting the activation and proliferation of cytotoxic T cells. In some viral infections and tumor immune processes, CD4+... + T cells regulate the direction and intensity of the immune response by interacting with antigen-presenting cells (such as dendritic cells) and cytotoxic T cells.

[0047] This test case aims to use flow cytometry to detect surface markers (CD3, CD4, CD8) of the immortalized T cell line SZ906 derived from peripheral blood of hematological malignancy patients obtained in Example 1, in order to further verify the cell line to which the immortalized T cell line SZ906 derived from peripheral blood of hematological malignancy patients obtained in Example 1 belongs. The detection results of the surface markers CD3, CD4, and CD8 of the immortalized T cell line SZ906 are as follows: Figure 4 As shown, where, Figure 4 Figure A in the diagram shows the flow cytometry results for CD3. Figure 4 Figure B in the diagram shows the flow cytometry results for CD4 / CD8.

[0048] Depend on Figure 4 It can be seen that the immortalized T cell line SZ906 derived from peripheral blood of patients with hematologic malignancies had a CD3 positivity rate of 96.5%, which conforms to the classic T cell immunophenotypic indicators; a CD4 positivity rate of 98.9%; and a CD8 positivity rate of 4.7%. + CD8 - The positive rate was 94.3%, which is relatively high, indicating that the immortalized T cell line SZ906 has strong cytotoxicity against tumor cells, can kill tumor cells and clear cells infected by pathogens.

[0049] Test Example 4 This test case aims to investigate the safety of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancies patients obtained in Example 1. The specific experimental procedures are as follows: 0.6 wt% agarose was added to the T cell culture medium (see Example 1) to prepare a bottom agarose layer containing T cells with a final agarose concentration of 0.6 wt%. The layer was allowed to solidify at room temperature, and 1.0 × 10⁻⁶ cells were collected. 4 Immortalized T cell line SZ906 was mixed with a top layer of agarose containing T cell culture medium and a final agarose concentration of 0.35 wt%, and then quickly added to the solidified bottom layer of agarose. The mixture was left to solidify at room temperature, and 1 mL of T cell culture medium was added to keep it moist. Every 7 days, 1 mL of supernatant was discarded, and 1 mL of fresh T cell culture medium was added. On day 21, photographs were taken to record and the number of colonies formed was calculated. The results are as follows: Figure 5 As shown.

[0050] Depend on Figure 5 The soft agar tumorigenesis test results of the immortalized T cell line SZ906 showed that the immortalized T cell line SZ906 did not form tumors. This indicates that the immortalized T cell line SZ906 derived from the peripheral blood of hematologic malignancies provided by this invention has good safety and will not pose a risk of tumorigenesis during clinical application.

[0051] Test Example 5 This test case aims to detect the cytotoxicity of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients obtained in Example 1 against human ovarian cancer cells HO-8910. The specific experimental procedures are as follows: (1) Target cell plating: Human ovarian cancer cells HO-8910 were cultured in an incubator. After removing the HO-8910 cells from the incubator, cell growth was observed under a microscope. The cell confluence was approximately 80%–90%. The old culture medium was discarded, and 6 mL of DMEM culture medium was pipetted into the culture flask. The flask was gently shaken and washed, then discarded. 3 mL of 0.25% DMEM culture medium was added. Trypsin-EDTA digestion solution (1X) was incubated at 37°C for 1.5-2 minutes. Most cells detached. Digestion was stopped with 6 mL of DMEM medium containing 10% fetal bovine serum (FBS), and the cells were resuspended. The cell suspension was transferred to a 50 mL centrifuge tube, and the culture flask was rinsed with 6 mL of DMEM medium containing 10% FBS. The washing solution was transferred to a 50 mL centrifuge tube and centrifuged at 250 g for 4 minutes. After centrifugation, the supernatant was discarded, and the cells were resuspended in DMEM medium containing 10% FBS. Cells were counted using a cell counter. Human ovarian cancer cells HO-8910 were then seeded into 16-well E-Plates and cultured for 16-28 hours. (2) Effector cell killing: The cells to be tested (also called effector cells, i.e., the immortalized T cell line SZ906 derived from peripheral blood of a hematologic malignancy patient obtained in Example 1) were added to 16 wells of an E-Plate containing human ovarian cancer cells HO-8910 at an effector cell:tumor cell ratio of 1:0.5. The instrument readings were monitored, and the killing ratio of the immortalized T cell line SZ906 against human ovarian cancer cells HO-8910 was calculated. The results are as follows: Figure 6 As shown, Jurkat cells (T cells) were added as a control.

[0052] Depend on Figure 6It was found that both Jurkat cells and the immortalized T cell line SZ906 exhibited killing effects against human ovarian cancer cells HO-8910. Furthermore, the killing percentage of the immortalized T cell line SZ906 against human ovarian cancer cells HO-8910 was close to 0.8% (killing rate close to 80%), significantly higher than the killing rate of Jurkat cells against human ovarian cancer cells HO-8910 (less than 10%). These results demonstrate that the immortalized T cell line SZ906 derived from peripheral blood of hematological malignancy patients provided by this invention possesses strong killing ability against tumor cells (including human ovarian cancer cells), and can be applied in the preparation of anti-tumor drugs. The resulting anti-tumor drugs have strong killing ability against tumor cells and have broad application prospects in the clinical treatment of tumors.

[0053] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention, but such modifications or substitutions are all within the scope of protection of the present invention.

Claims

1. An immortalized T cell line SZ906 derived from peripheral blood of a hematologic malignancy patient was deposited at the Guangdong Provincial Center for Microbial Culture Collection on December 25, 2025, with accession number GDMCC No: 67533.

2. The immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients as described in claim 1, characterized in that, The immortalized T cell line SZ906 was prepared through the following steps: S1. Peripheral blood mononuclear cells were isolated from the peripheral blood of patients with hematologic malignancies; S2.Use STEMdiff TM The T cell kit was used to culture the peripheral blood mononuclear cells to obtain peripheral blood T cells; S3. The peripheral blood T cells were further cultured using T cell culture medium to obtain the immortalized T cell line SZ906; The T cell culture medium includes the following components: 500~2000 U / mL IL-2 and basal culture medium.

3. The immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients as described in claim 2, characterized in that: In S3, the basal culture medium is ALyS505NK-EX serum-free cell culture medium.

4. The immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients as described in claim 2, characterized in that, S3 includes the following operation: culturing the peripheral blood T cells in T cell culture medium for 3-7 days, and adding the T cell culture medium to the culture system to adjust the cell density of the culture system to (0.5-2.5) × 10⁻⁶ cells / day. 6 Cells / mL were cultured until significant cell growth was observed, thus obtaining the immortalized T cell line SZ906.

5. The application of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients as described in claim 1 in the preparation of antitumor drugs.

6. The application of the immortalized T cell line SZ906 derived from peripheral blood of hematologic malignancy patients as described in claim 5 in the preparation of antitumor drugs, characterized in that: The tumors include ovarian cancer.

7. An antitumor drug composition, characterized in that: The antitumor drug composition contains the immortalized T cell line SZ906 derived from the peripheral blood of a hematologic malignancy patient as described in claim 1.

8. The antitumor pharmaceutical composition according to claim 7, characterized in that: The tumors include ovarian cancer.

9. An antitumor drug composition, characterized in that: The antitumor drug composition contains CAR-T cells constructed by gene editing based on the immortalized T cell line SZ906 derived from peripheral blood of patients with hematologic malignancies as described in claim 1.

10. The antitumor pharmaceutical composition according to claim 9, characterized in that: The tumors include ovarian cancer.

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