ANTICANCER AGENT COMPRISING ANTI-PD-1 ANTIBODY OR ANTI-PD-L1 ANTIBODY
Provided is an anticancer agent which comprises an anti-PD-1 antibody or an anti-PD-L1 antibody as an active ingredient, functioning to reverse the unresponsiveness of iNKT cells in which anergy has been induced by administration with an iNKT cell ligand. The anti-PD-1 or anti-PD-L1 antibody blocks the PD-1/PD-L1-mediated signaling pathway not only to prevent the iNKT cell ligand-induced iNKT cell anergy, but also to reverse the unresponsiveness of already anergic iNKT cells to produce cytokines. In addition, the anti-PD1 or anti-PD-L1 antibody ensures the potent anti-tumor activity of iNKT cells as demonstrated by a significant reduction in the number of metastatic nodules in B16F10 melanoma metastasis models in vivo. Collectively, the anticancer agent can be very useful in the treatment of cancer, particularly metastatic cancer.
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This application claims priority from Korean Patent Application No.10-2008-0097236, filed Oct. 2, 2008, the entire disclosure of which is incorporated herein by reference in its entirety.
TECHNICAL FIELDThe present invention relates, in general, to an anticancer agent and, more particularly, to an anticancer agent comprising an anti-PD-1 antibody or an anti-PD-L1 antibody as an active ingredient, functioning to restore the responsiveness of iNKT cells in which anergy has been induced by administration with an iNKT cell ligand.
BACKGROUND OF THE INVENTIONNatural killer T (NKT) cells, co-expressing a T cell receptor and NK cell markers, are essential for several aspects of immunity, such as immunomodulation and immunuopotentiation, in various immune diseases including autoimmune diseases, infectious diseases, cancer, etc. NKT cells exist at high levels in the thymus, the liver, and the bone marrow, but at low levels in the spleen, lymph nodes and blood.
Unlike conventional T cells that recognize small peptide antigens presented by major histocompatibility complex MHC class 1 or MHC class 2, NKT cells recognize glycolipid antigens presented by CD1d, a MHC class 1-like molecule. A major subset of NKT cells, called type 1 NKT cells or invariant natural T (iNKT) cells, express an invariant natural T cell receptor (TCR) composed of Vα14-Jα18 chains in mice (Vα24-Jα18 in humans). Upon TCR stimulation with a ligand, such as α-galactosylceramide (α-GC), iNKT cells rapidly produce a wide range of cytokines including IL-4, IFN-γ, L-12, and GM-CSF. This rapid and potent response to a ligand enables iNKT cells to enhance or regulate the activity of various immune cells in innate and acquired immunity. Found in diverse diseases and promoting tumor rejection or regulating autoimmune disorders, these immunomodulatory roles of iNKT cells are studied for use in immunotherapy treatments for cancer and autoimmune diseases.
However, iNKT cells tend to greatly decrease in responsiveness following repeated stimulation after a first stimulation with their ligands via the T cell receptor. For instance, iNKT cells that have been stimulated in vivo with a-GC have reduced proliferation and cytokine production upon secondary stimulation with the same ligand. This iNKT cell anergy is a major obstacle in immunotherapeutic trials targeting iNKT cells.
Conventional T cells are known to become anergic when they receive a TCR signal with insufficient co-stimulatory signals. Co-stimulatory molecules such as CD28, CD40L and ICOS are known to be involved in the development and activation of iNKT cells. Recently, it has been reported that 4-1BB contributes to promote the activation of iNKT cells as a co-stimulatory molecule and can affect iNKT cell-mediated allergic lung inflammation (Kim, D. H., W. S. Chang, Y. S. Lee, K. A. Lee, Y. K. Kim, B. S. Kwon, and C. Y. Kang. 2008. 4-1BB engagement co-stimulates NKT cell activation and exacerbates NKT cell ligand-induced airway hyperresponsiveness and inflammation. J Immunol 180:2062-2068.). On the other hand, it has recently been suggested that coinhibitory molecules, such as PD-1, B7H3, and B7H4, may actively anergize or tolerize T cells by delivering inhibitory signals into TCR-stimulated T cells. In a lymphocytic choriomeningitis virus (LCMV) infected model, CD8 T cells are tolerized by LCMV epitope-presenting dendritic cells. However, the blockade of the PD-1 signal can reverse the anergic phenotype of CD8 T cells. It has also been reported that the inhibition of PD-1/PD-L1 restores the function of exhausted CD8 T cells in a chronic infection model.
Programmed death-1 (PD-1) is a 55 KDa type 1 transmebrane protein of the immunoglobulin superfamily, and is known as a co-inhibitory molecule on T cells. That is, PD-1 is a member of the co-inhibitory molecules of the CD28 family (e.g., CD28, CTLA4, ICOS and BTLA) expressed on activated B cells, T cells and bone marrow cells. Two ligands for PD-1, PD-L1 and PD-L2, have been identified thus far. The interaction of PD-1 with the PD ligands can transduce inhibitory or co-stimulatory signals into the T cells. In conventional T cells, PD-1 is not expressed on naive T cells, but is inducibly expressed after T cell activation. As for PD-L1, it is expressed to some degree on naive T cells and its level is increased on activated T cells. PD-L1 is found at high levels in various human cancers and interacts with PD-1 to transduce inhibitory or co-stimulatory signals from entering into the T cells. For example, the interaction between PD-1 and PD-L1 induces a decrease in the level of tumor invasive lymphocytes and in T cell receptor-mediated proliferation and causes the immune evasion of tumor cells. In PD-1-deficient animals, PD-1 develops various autoimmune phenotypes, such as autoimmune cardiac infarction and lupus-like syndromes with arthritis and nephritis, and plays an important role in the development of autoimmune encephalomyelitis, systemic lupus erythematosus, graft-versus-host disease (GVHD), type 1 diabetes and rheumatic arthritis. Aged PD-1-deficient mice develop autoimmune diseases, indicating that PD-1 plays a critical role in the regulation of autoimmunity and immune tolerance. In particular, PD-1 signals are essential for inducing T cell exhaustion during chronic infection.
With the ability thereof to stimulate the T cell receptor to rapidly produce various cytokines of iNKT cells, the NKT cell ligand α-GC has conventionally been used as an anticancer agent. However, since repeated stimulation of iNKT cells with α-GC induces anergy leading to a great decrease in responsiveness, it cannot achieve effective anticancer effects. Therefore, there is a pressing need for an anticancer agent that can restore the responsiveness of iNKT cells even in the state of anergy caused by stimulation with iNKT cell ligands.
Leading to the present invention, intensive and thorough research into an anticancer agent taking advantage of the responsiveness of iNKT cells, conducted by the present inventors, resulted in the finding that PD-1 expressed on iNKT cells is upregulated after stimulation and that blocking of the PD-1/PD-L1 signaling pathway by an anti-PD-1 or anti-PD-L1 antibody allows iNKT cells under an iNKT cell ligand-induced anergy condition to recover their responsiveness, such as the production of cytokines. Also, the anti-PD1 or anti-PD-L1 antibody was found to induce potent anti-tumor activity of iNKT cells as demonstrated by a significant reduction in the number of metastatic nodules in B16F10 melanoma metastasis models in vivo.
SUMMARY OF THE INVENTIONIt is therefore an object of the present invention to provide an anticancer agent which is based on the activity of iNKT cells, featuring the recovery of iNKT cell responsiveness.
It is another object of the present invention to provide a method for the treatment of cancer using the same.
The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
In accordance with an aspect thereof, the present invention provides an anticancer agent, comprising an iNKT cell ligand as a first anticancer factor and an anti-PD-1 antibody or anti-PD-L1 antibody as a second anticancer factor, having a function of reversing unresponsiveness of iNKT cells in which anergy is induced by administration with the iNKT cell ligand.
In accordance with another aspect thereof, the present invention provides a method for reversing the unresponsiveness of iNKT cells with anergy induced therein by iNKT cell ligand treatment, comprising treating the anergic iNKT cells with an anti-PD-1 antibody or an anti-PD-L1 antibody.
The iNKT cell ligand may be selected from a group consisting of alpha-galactosyl ceramide, alpha-glucuronosyl ceramide, phosphatidylinositoltetramannoside, isoglobotrihexosylceramide, ganglioside GD3, phsphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, sulfatide, beta-galactosylceramide, lipophosphoglycan, glycoinositol phospholipid, alpha-galactosylceramide analogs including beta-anomer galactoceramide and alpha-anomer galactosylceramide, and bacterial lipid antigens.
The anti-PD-1 antibody or the anti-PD-L1 antibody may be a monoclonal antibody or a polyclonal antibody.
The anti-PD-1 antibody or anti-PD-L1 antibody according to the present invention can block the signaling of PD-1 or PD-L1 to prevent the iNKT cell ligand-induced anergy of iNKT cells and can provide cytokine secretion ability for even anergic iNKT cells to restore their responsiveness. In addition, the anti-PD-1 antibody or anti-PD-L1 antibody of the present invention inhibits the anergy induction of iNKT cells to significantly decrease the number of pulmonary nodules in a lung metastasis model of B16F10 melanoma, thus effectively eliciting anticancer immune responses of iNKT cells and showing anti-tumor effects of iNKT cells against cancer metastasis. Therefore, an anticancer agent comprising the anti-PD-1 antibody or anti-PD-L 1 antibody of the present invention can be very useful in the treatment of cancer, particularly, metastatic cancer.
The cancer to which the anticancer agent according to the present invention is therapeutically applicable may be gynecologic tumor, endocrine gland cancer, CNS (central nervous system) tumor or ureter cancer. Concrete examples of the cancer include lung cancer, stomach cancer, liver cancer, bone cancer, pancreatic cancer, skin cancer, head and neck cancer, melanoma, uterine cancer, ovarian cancer, rectal cancer, colorectal cancer, colon cancer, breast cancer, uterine sarcoma, Fallopian tube carcinoma, endometrial carcinoma, uterine cervical carcinoma, vaginal carcinoma, vulva carcinoma, esophageal cancer, larynx cancer, small intestine cancer, thyroid cancer, parathyroid cancer, soft tissue sarcoma, uterine cancer, penis cancer, prostate cancer, chronic or acute leukemia, pediatric solid tumor, differentiated lymphoma, bladder cancer, kidney cancer, renal cell carcinoma, renal pelvic carcinoma, primary CNS lymphoma, spinal cord tumor, brainstem glioma, and pituitary adenoma.
The anticancer agent of the present invention may be formulated into a pharmaceutical composition with at least one conventional anticancer ingredient.
In addition to the active ingredients, the pharmaceutical composition may further comprise a pharmaceutically acceptable carrier. Examples of the pharmaceutically acceptable carrier include saline, sterile water, Ringer's solution, buffered saline, dextrose solution, maltodextrin solution, glycerol, ethanol, etc. Optionally, conventional additives, such as antioxidants, buffers, bacteriostatic agents, etc., may be added to the composition. For the preparation of dosage forms including injections, such as aqueous solutions, suspensions and emulsions, pills, capsules, granules and tablets, the active ingredients may be admixed with a diluent, a dispersant, a surfactant, a binder and/or a lubricant. Reference may be made to literature (Remington's Pharmaceutical Science (recent edition), Mack Publishing Company, Easton Pa.) upon the formulation of the pharmaceutical composition into suitable dosage forms.
The composition of the present invention may be administered via oral routes or parenteral routes (e.g., intravenous, subcutaneous, intraperitoneal, topical, etc.). The effective dosage of the anticancer agent in accordance with the present invention depends on various factors, including the patient's weight, age, gender, state of health, diet, the time of administration, route of administration, excretion rate, severity of diseases, etc. In general, it may be administered in a single dose, and preferably in multiple doses per day at a daily dose ranging from 0.01 to 1000 mg/day, and preferably from 0.1 to 100 mg/kg of the anti-PD-1 antibody or anti-PD-L1 antibody.
For the effective prophylaxis and treatment of cancer, the composition according to the present invention may be used alone or in combination with surgical operation, hormonal therapy, chemotherapy, and/or biological response controllers.
A better understanding of the present invention may be obtained through the following examples which are set forth to illustrate, but are not to be construed as limiting the present invention.
EXAMPLES Example 1 Expression of PD-1 and PD Ligands in iNKT Cells1. Experimental Animals
Six- to eight-week-old female C56BL/6 mice were purchased from Orient Bio. All mice were bred and maintained in specific pathogen-free conditions.
2. Reagents and Antibodies
α-GC was dissolved in PBS containing 0.5% Tween 20. Hybridoma clones producing antibodies to mouse PD-1 (RMP1-14, rat IgG2a), PD-L1 (MIH-5, rat IgG2a), and PD-L2 (Ty25, rat IgG2a) were produced according to methods well known in the art [Yamazaki, T., H. Akiba, H. Iwai, H. Matsuda, M. Aoki, Y. Tanno, T. Shin, H. Tsuchiya, D. M. Pardoll, K. Okumura, M. Azuma, and H. Yagita. 2002. Expression of programmed death 1 ligands by murine T cells and APC. J Immunol 169:5538-5545.; Tsushima, F., H. Iwai, N. Otsuki, M. Abe, S. Hirose, T. Yamazaki, H. Akiba, H. Yagita, Y. Takahashi, K. Omura, K. Okumura, and M. Azuma. 2003. Preferential contribution of B7-H1 to programmed death-1-mediated regulation of hapten-specific allergic inflammatory responses. Eur J Immunol 33:2773-2782.; Yamazaki, T., H. Akiba, A. Koyanagi, M. Azuma, H. Yagita, and K. Okumura. 2005. Blockade of B7-H1 on macrophages suppresses CD4+ T cell proliferation by augmenting IFN-gamma-induced nitric oxide production. J Immunol 175:1586-1592.]. All clones were cultured in RPMI 1640 (Gibco) with 10% FBS (Gibco) and 1% penicillin/streptomycin (BioWhittaker). All antibodies were prepared from the ascites of nude mice using caprylic acid purification. Control rat IgG was also prepared by caprylic acid purification from sera of naïve rats.
3. Expression of PD-1 and PD Ligands on iNKT Cells After α-GC Administration
Splenocytes were isolated from C57BL/6 mice administered with 2 μg of α-GC at different time points (0 hr, 6 hrs, 72 hrs, 7 days, one month and two months) after the administration. The cells were stained with a PE-conjugated anti-PD-1 monoclonal antibody, a PE-conjugated anti-PD-L1 monoclonal antibody, a PE-conjugated anti-PD-L2 monoclonal antibody and a PE-conjugated isotype control monoclonal antibody, respectively. iNKT cells were gated on B220− TCR-βintα-GC/CD1d:Ig+ population. PD-1, PD-L1 and PD-L2 expression (open histograms) was analyzed by FACS. The results are given in
As depicted in
The following in vitro and in vivo experiments were conducted to examine the effects of PD-1, PD-L1 and PD-L2 on iNKT cell activation.
1. iNKT Cell Activation In Vitro
After being prepared from naëve C57BL/6 mice, 5×105 spelenocytes were incubated for 3 days with 100 ng/ml of α-GC in the presence of 50 μg/ml of the control rat IgG, the anti-PD-1 mAb, the anti-PD-L1 mAb, or the anti-PD-L2 mAb. Then, the supernatants were obtained and assayed for IFN-γ and IL-4 levels by ELISA.
The results are given in
Compared with control IgG treatment, as is apparent from
2. iNKT Cell Activation in Vivo
C57BL/6 mice was injected with 200 μg of the control rat IgG, the anti-PD-1 mAb, the anti-PD-L1 mAb or the anti-PD-L2 mAb 24 hrs before treatment with 2 μg of α-GC. Sera were obtained at 0, 2, 6, 12, 24, 48 and 72 hrs after the treatment, followed by ELISA analysis for IFN-γ and IL-4 levels.
In order to determine whether the increased production of IFN-γ was distinctively attributed to iNKT cells, intracellular cytokine staining was followed by flow cytometry analysis. In this regard, splenocytes were isolated 2 hrs after α-GC treatment and 5×106 cells were incubated with Golgi plug for 2 hrs to accumulate cytokines. Intracellular cytokine staining was performed using BD Cytofix/Cytoperm Plus with Golgiplug kit according to the manufacturer's protocol (BD Biosciences). iNKT cells were gated on B220−TCR-βint α-GC/CD1d:Ig+ population and IFN-γ+ or IL-4+ iNKT cells were analyzed by flow cytometry.
IFN-γ and IL-4 levels in blood are depicted in
As shown in
As shown in
The following in vitro and in vivo experiments were performed in order to examine whether the blockage of PD-1/PD-L 1 interaction reverses iNKT cell anergy.
1. Recovery of Responsiveness of Anergic iNKT Cells in Vitro
The α-GC-induced unresponsiveness of iNKT cells was detected as early as 3 days after primary stimulation and observed to persist until 7˜30 days after α-GC stimulation. Thus, C57BL/6 mice were injected with 2 μg of α-GC to induce iNKT cell anergy. One week and one month later, splenocytes were isolated from the mice and 5×105 cells were incubated for 3 days with 100 ng/ml of α-GC in the presence of 50 μg/ml of the control rat IgG, the anti-PD-1 mAb, the anti-PD-L1 mAb, or the anti-PD-L2 mAb. Also, splenocytes isolated from the mice were incubated for 3 days with 10 ng/ml of α-GC without mAb, and these were represented by ‘activation’. The supernatants were then assayed for IFN-γ and IL-4 levels by ELISA [*:p<0.05 and **:p<0.01 (vs. control rat IgG)].
The results are depicted in
As seen in the graphs of
2. Recovery of Responsiveness of Anergic iNKT Cells in Vivo
200 μg of the control rat IgG, the anti-PD-1 antibody or the anti-PD-L1 antibody was intraperitoneally injected into C57BL/6 mice 24 hrs before treatment with 2 μg of α-GC. 14 days later, 2 μg of α-GC was injected again, followed by the preparation of sera 2 and 12 hrs after the re-injection for ELISA assay of IL-4 and IFN-γ levels, respectively.
Splenocytes (5×106 cells), prepared two and twelve hours after the second injection of α-GC, were incubated with Golgi plug for 2 hrs to accumulate cytokines. Intracellular cytokine staining was performed on the splenocytes prepared 2 hrs after the secondary GC treatment, using BD Cytofix/Cytoperm Plus with Golgiplug kit according to the manufacturer's protocol (BD Biosciences). The splenocytes prepared 12 hrs later were used in an assay for CD69 expression in iNKT and NK cells. iNKT cells were gated on B220−TCR-βintα-GC/CD1d:1g+ population and NK cells were gated on B220− TCR-β−NK1.1high population. IFN-γ+ or IL-4+ iNKT cells were analyzed by flow cytometry. Also, CD69 expression on iNKT and NK cells was analyzed by flow cytometry.
IFN-γ and L-4 levels in blood are graphed in
Like mice treated with control rat IgG, as seen in
As seen in
It was also found that CD69 expression upon secondary α-GC injection was increased on iNKT and NK cells in a similar manner by the treatment with anti-PD-1 mAbs, as shown in
The following experiments were performed to investigate the effects of the anti-PD-1 antibody or the anti-PD-L1 antibody on the anticancer activity of activated iNKT cells in a B16F10 melanoma metastasis model.
1. Weight of Lung
Skin tumor cells (B16F10, ATCC) were cultured in DMEM media supplemented with 10% FBS and 1% penicillin/streptomycin. C56BL/6 mice were intraperitoneally injected with 200 g of the control rat IgG, the anti-PD-1 mAb orthe anti-PD-L1 mAb 24 hrs before i.v. inoculation with 2×105 tumor cells. On Days zero, 4 and 8, the mice were treated with 500 ng of α-GC plus 200 μg of the control rat IgG, the anti-PD-1 mAb or the anti-PD-L1 mAb. On Day 14, the lungs were weighed and weight differences between metastatic and normal lungs are graphed in
As depicted in
2. Number of Pulmonary Nodules
Anergy-induced iNKT cells were assayed for the recovery of anti-tumor activity by the antibodies of the present invention. In this regard, naive C57BL/6 mice were intraperitoneally injected with 200 μg of the control rat IgG, the anti-PD-1 antibody or the anti-PD-L1 antibody 24 hrs after which injection with 2 μg of α-GC induced iNKT cell anergy. 7 days later, 5×105 B16F10 tumor cells were i.v. injected. On Day 0, 4 and 8, the mice were treated with 500 ng of α-GC to induce anti-tumor activity of iNKT cells. 14 days later, the lungs were excised and the nodules formed by cancer metastasis were counted (A). The isolated lungs were observed under an optical microscope (B). The results are given in
As seen in
Formulation examples are given to illustrate dosage preparations containing the anticancer agent of the present invention.
Formulation Example 1 Preparation of Powder
These ingredients were mixed and loaded into an airtight sac to give a powder.
Formulation Example 2 Preparation of Tablet
These ingredients were mixed and directly compressed into a tablet.
Formulation Example 3 Preparation of Capsule
These ingredients were admixed together and the admixture was loaded into a conventional capsule using a suitable device.
Formulation Example 4 Preparation of Injection
Using a conventional method, these ingredients were put into an ampule (2 ml) to give an injection.
Formulation Example 5 Preparation of Liquid Medicine
Each ingredient was dissolved in purified water and flavored with lemon before admixing together. Purified water was added to the admixture to form a final volume of 100 ml which was then loaded into a brown vial and sterilized.
As described hitherto, the anti-PD-1 or anti-PD-L1 antibody according to the present invention blocks the PD-1/PD-L1-mediated signaling pathway not only to prevent the iNKT cell ligand-induced iNKT cell anergy, but also to reverse the unresponsiveness of already anergic iNKT cells to produce cytokines. In addition, the anti-PD1 or anti-PD-L1 antibody ensures the potent anti-tumor activity of iNKT cells as demonstrated by a significant reduction in the number of metastatic nodules in B16F10 melanoma metastasis models in vivo. Collectively, the anticancer agent comprising an anti-PD-1 or anti-PD-L1 antibody in accordance with the present invention can be very useful in the treatment of cancer, particularly metastatic cancer.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.
Claims
1. An anticancer agent, comprising an iNKT cell ligand as a first anticancer factor and an anti-PD-1 antibody or anti-PD-L1 antibody as a second anticancer factor, having a function of reversing unresponsiveness of iNKT cells in which anergy is induced by administration with the iNKT cell ligand.
2. The anticancer agent as defined in claim 1, wherein the iNKT cell ligand is selected from a group consisting of alpha-galactosyl ceramide, alpha-glucuronosyl ceramide, phosphatidylinositoltetramannoside, isoglobotrihexosylceramide, ganglioside GD3, phsphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, sulfatide, beta-galactosylceramide, lipophosphoglycan, glycoinositol phospholipid, alpha-galactosylceramide analogs including beta-anomer galactoceramide and alpha-anomer galactosylceramide, and bacterial lipid antigens.
3. The anticancer agent as defined in claim 1, wherein the anti-PD-1 antibody or the anti-PD-L1 antibody is a monoclonal antibody or a polyclonal antibody.
4. The anticancer agent as defined in claim 1, wherein the cancer is selected from a group consisting of lung cancer, stomach cancer, liver cancer, bone cancer, pancreatic cancer, skin cancer, head and neck cancer, melanoma, uterine cancer, ovarian cancer, rectal cancer, colorectal cancer, colon cancer, breast cancer, uterine sarcoma, Fallopian tube carcinoma, endometrial carcinoma, uterine cervical carcinoma, vaginal carcinoma, vulva carcinoma, esophageal cancer, larynx cancer, small intestine cancer, thyroid cancer, parathyroid cancer, soft tissue sarcoma, uterine cancer, penis cancer, prostate cancer, chronic or acute leukemia, pediatric solid tumor, differentiated lymphoma, bladder cancer, kidney cancer, renal cell carcinoma, renal pelvic carcinoma, primary CNS lymphoma, spinal cord tumor, brainstem glioma, and pituitary adenoma.
5. A method for reversing the unresponsiveness of iNKT cells with anergy induced therein by iNKT cell ligand treatment, comprising treating the anergic iNKT cells with an anti-PD-1 antibody or an anti-PD-L1 antibody.
6. The method as defined in claim 5, wherein the iNKT cell ligand is selected from a group consisting of alpha-galactosyl ceramide, alpha-glucuronosyl ceramide, phosphatidylinositoltetramannoside, isoglobotrihexosylceramide, ganglioside GD3, phsphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, sulfatide, beta-galactosylceramide, lipophosphoglycan, glycoinositol phospholipid, alpha-galactosylceramide analogs including beta-anomer galactoceramide and alpha-anomer galactosylceramide, and bacterial lipid antigens.
7. The method as defined in claim 5, wherein the anti-PD-1 antibody or the anti-PD-L1 antibody is a monoclonal antibody or a polyclonal antibody.
Type: Application
Filed: Mar 25, 2009
Publication Date: Apr 8, 2010
Applicant: Seoul National University Industry Foundation (Seoul)
Inventors: Chang Yuil Kang (Seoul), Woo Sung Chang (Gyeonggi-do), Ji Yeon Kim (Seoul)
Application Number: 12/410,732
International Classification: A61K 39/395 (20060101);