Novel biologics that redirect cytotoxic T lymphocytes (CTLs) to kill tumor cells bearing a tumor associated antigen hold great promise in the clinic. However, the ability to safely and potently target CD3 on CTL toward tumor associated antigens (TAA) expressed on tumor cells remains a challenge of both technology and biology. Herein we describe the use of a Half DVD-Ig format that can redirect CTL to kill tumor cells. Notably, Half DVD-Ig molecules that are monovalent for each specificity demonstrated reduced non-specific CTL activation and conditional CTL activation upon binding to TAA compared to intact tetravalent DVD-Ig molecules that are bivalent for each specificity, while maintaining good drug like properties and appropriate PK properties.
Animals ; Antibodies, Bispecific ; immunology ; Antibodies, Monoclonal ; immunology ; pharmacokinetics ; CD3 Complex ; metabolism ; Cell Line, Tumor ; Cytotoxicity, Immunologic ; ErbB Receptors ; metabolism ; Female ; Humans ; Lymphocyte Activation ; immunology ; Mice, SCID ; Neoplasms ; immunology ; pathology ; Rats, Sprague-Dawley ; T-Lymphocytes, Cytotoxic ; immunology

PURPOSE: Acute hepatitis A (AHA) and acute hepatitis B (AHB) are caused by an acute infection of the hepatitis A virus and the hepatitis B virus, respectively. In both AHA and AHB, liver injury is known to be mediated by immune cells and cytokines. In this study, we measured serum levels of various cytokines and T-cell cytotoxic proteins in patients with AHA or AHB to identify liver injury-associated cytokines. MATERIALS AND METHODS: Forty-six patients with AHA, 16 patients with AHB, and 14 healthy adults were enrolled in the study. Serum levels of 17 cytokines and T-cell cytotoxic proteins were measured by enzyme-linked immunosorbent assays or cytometric bead arrays and analyzed for correlation with serum alanine aminotransferase (ALT) levels. RESULTS: Interleukin (IL)-18, IL-8, CXCL9, and CXCL10 were significantly elevated in both AHA and AHB. IL-6, IL-22, granzyme B, and soluble Fas ligand (sFasL) were elevated in AHA but not in AHB. In both AHA and AHB, the serum level of CXCL10 significantly correlated with the peak ALT level. Additionally, the serum level of granzyme B in AHA and the serum level of sFasL in AHB correlated with the peak ALT level. CONCLUSION: We identified cytokines and T-cell cytotoxic proteins associated with liver injury in AHA and AHB. These findings deepen the existing understanding of immunological mechanisms responsible for liver injury in acute viral hepatitis.
Acute Disease ; Adult ; Alanine Transaminase/blood ; Biomarkers/blood ; Cytokines/*blood ; Enzyme-Linked Immunosorbent Assay ; Fas Ligand Protein/blood ; Female ; Hepatitis A/blood/virology ; Hepatitis A virus/*genetics/immunology ; Hepatitis B/blood/virology ; Hepatitis B virus/*genetics/immunology ; Humans ; Interleukin-6/blood ; Interleukin-8/blood ; Interleukins/blood ; Liver Failure/immunology/metabolism/*pathology ; Male ; Middle Aged ; T-Lymphocytes, Cytotoxic/immunology/*metabolism

PURPOSE: Cutaneous lymphocyte-associated antigen (CLA)-expressing CD8+T cells have been known to play an important role in the pathogenesis of atopic dermatitis (AD). However, the mechanisms underlying the loss of self-tolerance remain unclear. Regulatory T cells (Tregs) play a key role in the development of homeostasis in the immune system. We, therefore, hypothesized that a reduced ability of Tregs to inhibit autologous CD8+CLA+T cells might be underlying mechanism in AD. MATERIALS AND METHODS: CD8+CLA+T cells and Tregs were obtained from the peripheral blood of AD patients and control volunteers. The frequencies of CD8+CLA+T cells were evaluated. The proliferative responses of CD8+CLA+T cells were assessed by flow cytometry, and the levels of transforming growth factor-beta1 (TGF-beta1) and interleukin-10 (IL-10) in culture supernatants were detected by enzyme-linked immunosorbent assay. RESULTS: Our results revealed higher frequency and increased expression of perforin and granzyme-B in peripheral CD8+CLA+T cells in AD, and lower inhibitory ability of Tregs on proliferation of CD8+CLA+T cells in AD. Meanwhile, the levels of TGF-beta1 produced by Tregs were significantly lower in AD, and anti-TGF-beta1 abolished such suppression. CONCLUSION: The attenuated inhibitory ability of Tregs on hyper-activated autologous CD8+CLA+T cells, mediated by TGF-beta1, plays an important role in the pathogenesis of AD.
Adult ; Aged ; CD8-Positive T-Lymphocytes/drug effects/*immunology ; Case-Control Studies ; Cell Proliferation ; Cell Separation ; Dermatitis, Atopic/*immunology/pathology ; Female ; Granzymes/metabolism ; Humans ; Interleukin-10/metabolism ; Lymphocyte Count ; Male ; Perforin/metabolism ; Skin/*immunology/pathology ; T-Lymphocytes, Cytotoxic/drug effects/immunology ; T-Lymphocytes, Regulatory/drug effects/*immunology ; Transforming Growth Factor beta1/pharmacology

We evaluated the effectiveness of rhamnogalacturonan II (RG-II)-stimulated bone marrow-derived dendritic cells (BMDCs) vaccination on the induction of antitumor immunity in a mouse lymphoma model using EG7-lymphoma cells expressing ovalbumin (OVA). BMDCs treated with RG-II had an activated phenotype. RG-II induced interleukin (IL)-12, IL-1beta, tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) production during dendritic cell (DC) maturation. BMDCs stimulated with RG-II facilitate the proliferation of CD8+ T cells. Using BMDCs from the mice deficient in Toll-like receptors (TLRs), we revealed that RG-II activity is dependent on TLR4. RG-II showed a preventive effect of immunization with OVA-pulsed BMDCs against EG7 lymphoma. These results suggested that RG-II expedites the DC-based immune response through the TLR4 signaling pathway.
Acute-Phase Proteins/metabolism ; Adaptor Proteins, Vesicular Transport/metabolism ; Animals ; Antigens, CD14/metabolism ; Bone Marrow Cells/cytology/drug effects ; CD8-Positive T-Lymphocytes/*immunology ; Carrier Proteins/metabolism ; Cell Differentiation/drug effects ; Cell Nucleus/drug effects/metabolism ; Cell Proliferation/drug effects ; Cytokines/biosynthesis ; Dendritic Cells/cytology/drug effects/enzymology/*immunology ; Enzyme Activation/drug effects ; Lymphocyte Activation/*drug effects ; Membrane Glycoproteins/metabolism ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Mitogen-Activated Protein Kinases/metabolism ; Myeloid Differentiation Factor 88/metabolism ; NF-kappa B/metabolism ; Neoplasms/immunology/*pathology ; Pectins/*pharmacology ; Phenotype ; Protein Transport/drug effects ; Receptors, Chemokine/metabolism ; Signal Transduction/drug effects ; T-Lymphocytes, Cytotoxic/cytology/drug effects ; Toll-Like Receptor 4/*agonists/metabolism

Establishing Epstein-Barr virus(EBV)-specific cytolytic T lymphocytes(EBV-CTLs) from peripheral blood mononuclear cells(PBMCs) for adoptive immunotherapy has been reported in EBV-associated malignancies including Hodgkin's lymphoma and nasopharyngeal carcinoma(NPC). In the current study, we performed ex vivo expansion of tumor-infiltrating lymphocytes(TILs) obtained from NPC biopsy specimens with a rapid expansion protocol using anti-CD3 monoclonal antibody(OKT3), recombinant human interleukin(IL)-2, and irradiated PBMCs from healthy donors to initiate the growth of TILs. Young TIL cultures comprised of more than 90% of CD3+ T cells, a variable percentage of CD3+CD8+ and CD3+CD4+ T cells, and less than 10% of CD3-CD16+ natural killer cells, a similar phenotype of EBV-CTL cultures from PBMCs. Interestingly, TIL cultures secreted high levels of the Th1 cytokines, interferon gamma (IFNγ) and tumor necrosis factor-alpha (TNF-α), and low levels of the Th2 cytokines, IL-4 and IL-10. Moreover, young TILs could recognize autologous EBV-transformed B lymphoblast cell lines, but not autologous EBV-negative blast cells or allogeneic EBV-negative tumor cells. Taken together, these data suggest that ex vivo expansion of TILs from NPC biopsy tissue is an appealing alternative method to establish T cell-based immunotherapy for NPC.
Biopsy ; CD3 Complex ; analysis ; CD4 Antigens ; analysis ; CD8 Antigens ; analysis ; Cells, Cultured ; Herpesvirus 4, Human ; immunology ; Humans ; Immunotherapy, Adoptive ; Interferon-gamma ; metabolism ; Interleukin-10 ; metabolism ; Interleukin-2 ; pharmacology ; Interleukin-4 ; metabolism ; Lymphocytes, Tumor-Infiltrating ; immunology ; virology ; Monocytes ; pathology ; Muromonab-CD3 ; pharmacology ; Nasopharyngeal Neoplasms ; immunology ; pathology ; therapy ; virology ; Receptors, IgG ; analysis ; T-Lymphocytes, Cytotoxic ; immunology ; virology ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo explore the anti-tumor mechanism of the combination of cisplatin with DC vaccine in tumor-bearing mice.

METHODSB16 melanoma cells were treated with cisplatin at the final concentration of 20 µg/ml in vitro for 24 h. The expression of HMGB1, Hsp70 and TGF-β were detected by Western blot. B16 tumor-bearing mouse models were generated. The therapeutic effect of the combination of cisplatin (100 µg/mouse i.p., for sequential 3 days) and intratumoral injection of DC cells (3×10(6)/mouse, twice with a 7-day interval) in the tumor-bearing mouse models was evaluated. Expression of MHC II, ICAM-1 and CD86 was analyzed by flow cytometry. The mice were sacrificed at 28 days after tumor cell inoculation. The tumors were removed and weighed, and tissue samples were taken for pathological examination. Tumor infiltrating lymphocytes (TIL) were isolated by discontinuous gradient centrifugation. The distribution of T-reg and CD8(+) T cells in the TIL was analyzed by flow cytometry, and the ratio of CD8(+) T/T-reg was determined. The activity of cytotoxic lymphocytes (CTL) was determined by microcytotoxicity assay.

RESULTSCisplatin enhanced both the B16 cell apoptosis and HMGB1 expression. After loading with cisplatin-treated cell lysate, the expression of MHC II, ICAM-1 and CD86 on DC cells were (47.5 ± 8.8)%, (35.5 ± 8.3)% and (36.2 ± 9.2)%, respectively. At 28 days after tumor cell inoculation, the tumor weight of the control group was (2.1 ± 0.6) g, that of the cisplatin group was (0.3 ± 0.2) g and that of cisplatin + DC vaccine group was (0.5 ± 0.2) g, showing a significant inhibition of tumor growth (P < 0.01). Furthermore, the CD8(+) T/T-reg ratio and CTL activity in TIL were also significantly enhanced in the tumor-bearing mice treated with cisplatin + DC vaccine. When the effector-to-target ratio was 20:1, 10:1 and 5:1, the CTL activity in the cisplatin + DC vaccine treated mice was (25.0 ± 5.0)%, (22.0 ± 6.0)% and (14.0 ± 4.0)%, respectively, significantly higher than (8.2 ± 3.6)%, (6.7 ± 1.8)% and (3.6 ± 1.9)%, respectively, in the control group (all P < 0.01).

CONCLUSIONCisplatin promotes the anti-tumor effect of DC vaccine by down-regulating T-reg cells and enhancing the CTL activity in tumors.

Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; B7-2 Antigen ; metabolism ; CD8-Positive T-Lymphocytes ; pathology ; Cancer Vaccines ; pharmacology ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Dendritic Cells ; immunology ; metabolism ; Female ; Genes, MHC Class II ; HMGB1 Protein ; metabolism ; Intercellular Adhesion Molecule-1 ; metabolism ; Melanoma, Experimental ; pathology ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; T-Lymphocytes, Cytotoxic ; immunology ; T-Lymphocytes, Regulatory ; pathology ; Tumor Burden ; drug effects

OBJECTIVETo explore the cytotoxic responses of spleen T lymphocytes (CTL) in BALB/c mice induced by recombinant HSP110-HER2/neu ICD complex.

METHODSTumor-bearing mouse model was immunized by HSP110-HER2/neu ICD complex. The IFN-γ level secreted by activated spleen T lymphocytes was detected by enzyme linked immunospot assay (ELISPOT). The corresponding CTL activity was measured by granzyme release assay.

RESULTSThe BALB/c mouse model of human mammary tumor highly expressing HER2/neu was established. HSP110-HER2/neu ICD complex immunization led to a significantly higher level of INF-γ than that in HSP110-P(789-797) immunized and HER2/neu ICD immunized mice. HSP110-HER2/neu ICD complex immunized animals also show significant CTL activity. The results of immunohistochemical staining showed that the number of blue spots in the PBS group was 4.57 ± 1.33, HSP110 group 6.83 ± 2.08, HER2/neu ICD group 16.17 ± 2.86, HSP110-P(789-797) group 43.67 ± 4.78, and SP110-HER2/neu ICD group 76.51 ± 8.17. The number of IFN-γ-secreting spleen lymphocytes in the HSP110-HER2/neu ICD group was significantly higher than that in the HSP110-P(789-797) group, and that of HSP110-P(789-797) group was significantly higher than that of HER2/neu ICD group (P < 0.01). The target cell-killing rate of the PBS group was (8.15 ± 1.27)%, HSP110 group (9.51 ± 1.51)%, HER2/neu ICD group (14.03 ± 2.45)%, HSP110-P(789-797) group (25.99 ± 3.04)% and HSP110-HER2/neu ICD group (38.15 ± 3.95)% (all P < 0.01).

CONCLUSIONSHSP110-HER2/neu ICD complex can promote the proliferation and maturation of T lymphocytes into CTLs, and might be used as anti-tumor vaccine to induce potent cytotoxic T lymophocyte immunoresponse against specific tumor cells.

Animals ; Breast Neoplasms ; metabolism ; pathology ; Cancer Vaccines ; immunology ; Cell Line, Tumor ; Cell Proliferation ; Female ; HSP110 Heat-Shock Proteins ; immunology ; Humans ; Interferon-gamma ; metabolism ; Lymphocyte Activation ; Mice ; Mice, Inbred BALB C ; Neoplasm Transplantation ; Random Allocation ; Receptor, ErbB-2 ; immunology ; metabolism ; Recombinant Proteins ; immunology ; Spleen ; cytology ; immunology ; T-Lymphocytes ; cytology ; immunology ; metabolism ; T-Lymphocytes, Cytotoxic ; immunology ; Vaccines, Synthetic ; immunology

Cancer cell vaccine-based immunotherapy has received increasing interest in many clinical trials involving patients with breast cancer. Combining with appropriate adjuvants can enhance the weak immunogenic properties of tumor cell lysates (TCL). In this study, diphtheria toxin (DT) and two tandem repeats of mycobacterial heat shock protein 70 (mHSP70) fragment 407-426 (M2) were conjugated to TCL with glutaraldehyde, and the constructed cancer cell vaccine was named DT-TCL-M2. Subcutaneous injection of DT-TCL-M2 in mice effectively elicited tumor-specific polyclonal immune responses, including humoral and cellular immune responses. High levels of antibodies against TCL were detected in the serum of immunized mice with ELISA and verified with Western blot analyses. The splenocytes from immunized mice showed potent cytotoxicity on Ehrlich ascites carcinoma cells. Moreover, the protective antitumor immunity induced by DT-TCL-M2 inhibited tumor growth in a mouse breast tumor model. DT-TCL-M2 also attenuated tumor-induced angiogenesis and slowed tumor growth in a mouse intradermal tumor model. These findings demonstrate that TCL conjugated with appropriate adjuvants induced effective antitumor immunity in vivo. Improvements in potency could further make cancer cell vaccines a useful and safe method for preventing cancer recurrence after resection.
Adjuvants, Immunologic ; Animals ; Bacterial Proteins ; genetics ; immunology ; Cancer Vaccines ; immunology ; Carcinoma, Ehrlich Tumor ; immunology ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Diphtheria Toxin ; genetics ; immunology ; Female ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Immunoglobulin G ; immunology ; Immunotherapy ; Mice ; Neovascularization, Pathologic ; Peptide Fragments ; genetics ; immunology ; Recombinant Fusion Proteins ; genetics ; immunology ; T-Lymphocytes, Cytotoxic ; immunology ; Tandem Repeat Sequences

OBJECTIVETo construct a recombinant plasmid pIRES-GM-CSF-IL-21, and to investigate its antitumor effect on tumors in the mice.

METHODSFifty Bal b/c mice were included in this study. Cultured hepatoma H22 cells were inoculated in the left lobe of the liver to develop orthotopically transplanted liver tumor models. The mice with orthotopically transplanted liver tumor were randomly divided into 5 groups (n = 10): (1) Each mouse received injection of recombinant plasmid pIRES-GM-CSF-IL-21; (2) Received injection of plasmid pIRES-GM-CSF; (3) pIRES-IL-21; (4) Received injection of ampty plasmid pIRES (H22/neo group); (5) Received injection of PBS (H22 group) via the tail vein, respectively. Therefore, the anti-tumor effect was induced by both GM-CSF and IL-21, or by either of them alone. The serum levels of IFN-γ and IL-2 were detected by ELISA, and the cytotoxicity of spleen NK and CTL cells were tested by MTT colorimetry.

RESULTSComparing with the H22 and H22/Neo groups, the tumor weight in the mice of H22/GM-CSF group was (0.603 ± 0.223) g, H22/IL21-treated group (0.583 ± 0.290) g and H22/GM-CSF-IL21-treated group (0.303 ± 0.323) g, significantly lower than that in the H22 group [(1.591 ± 0.280) g] and H22/Neo group [(1.489 ± 0.155) g]. Among them the tumor growth was most significantly inhibited in the H22/GM-CSF-IL-21 group (0.303 ± 0.323) g, compared with that of H22 and H22/neo groups (P < 0.01). But there was no significant difference between the tumor weights of the H22/GM-CSF group and H22/IL-21 group, and between the tumor weights of the H22 and H22/Neo groups (P > 0.05). The levels of IFN-γ and IL-2 in peripheral blood of mouse models treated with H22/GM-CSF-IL-21 were significantly increased than that in the H22/GM-CSF group and H22/IL-21 group (all P < 0.01), but significantly decreased in the H22group and H22/Neo group (P < 0.01). The anti-tumor activity of splenic NK cells and CTLs in the H22/GM-CSF-IL21 group was significantly enhanced (P < 0.01), compared with the significantly decreased in the H22 and H22/Neo groups.

CONCLUSIONSOur results demonstrate apparent antitumor effect of the plasmid pIRES-GM-CSF-IL-21 on the orthotopically transplanted liver tumor in mice. The combination of both pIRES-GM-CSF and IL-21 is more effective than that of pIRES/IL21 or pIRES/GM-CSF treatment alone. In addition, the plasmid pIRES-GM-CSF-IL-21 can also promote the secretion of IFN-γ and IL-2 in vivo, and enhance the cytotoxic activity of splenic NK and CTLs against the transplanted liver tumor.

Animals ; Carcinoma, Hepatocellular ; blood ; pathology ; therapy ; Cell Line, Tumor ; Female ; Granulocyte-Macrophage Colony-Stimulating Factor ; genetics ; Immunotherapy ; Interferon-gamma ; blood ; Interleukin-2 ; blood ; Interleukins ; genetics ; Killer Cells, Natural ; immunology ; Liver Neoplasms ; blood ; pathology ; therapy ; Mice ; Mice, Inbred BALB C ; Neoplasm Transplantation ; Plasmids ; therapeutic use ; Random Allocation ; Recombinant Proteins ; therapeutic use ; T-Lymphocytes, Cytotoxic ; immunology ; Tumor Burden

OBJECTIVETo prepare IL-2-anchored and tumor-derived exosomes vaccine, and investigate the antitumor efficiency of the special cytotoxic T-lymphocytes induced by Ex/GPI-IL-2.

METHODSTo construct pEGFP-N1-IL2gpi plasmid coding a fusion gene of a DNA oligo encoding GPI-anchor signal sequence attaching to human IL-2 cDNA. Then T24 cell lines stably expressing GPI-IL-2 proteins (T24/GPI-IL-2) were established. Ex/GPI-IL-2 were isolated and purified by ultrafiltration and sucrose gradient centrifugation, and the morphology and molecule markers were analyzed. The mixed lymphocyte reaction study and cytotoxic study were performed to determine the proliferative effect of T lymphocytes and the cytotoxicity induced by Ex/GPI-IL-2.

RESULTSThe pEGFP-N1-IL2gpi plasmid was successfully constructed, and cell lines stably expressing GPI-IL-2 fusion proteins were established. Ex/GPI-IL-2 were small vesicular and saucer-shaped in diameter of 30-90 nm, containing heat shock protein 70, intercellular adhesion molecule-1, MAGE-1 and GPI-IL-2. Ex/GPI-IL-2-pulsed could dendritic cells induce proliferation of T cells and cytotoxic immune response more efficiently (P<0.05).

CONCLUSIONSGPI-IL-2 gene-modified tumor cells can make the exosomes containing GPI-IL-2 with an increased anti-tumor effect. Our study provides a feasible approach for exosome-based tumor immunotherapy of bladder transitional cell tumors.

Cancer Vaccines ; immunology ; Carcinoma, Transitional Cell ; immunology ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Exosomes ; genetics ; metabolism ; Glycosylphosphatidylinositols ; metabolism ; HSP70 Heat-Shock Proteins ; metabolism ; Humans ; Intercellular Adhesion Molecule-1 ; metabolism ; Interleukin-2 ; metabolism ; Melanoma-Specific Antigens ; metabolism ; Plasmids ; Recombinant Fusion Proteins ; metabolism ; T-Lymphocytes, Cytotoxic ; immunology ; Transfection ; Urinary Bladder Neoplasms ; immunology ; metabolism ; pathology