OBJECTIVETo induce anti-B-cell acute lymphoblastic leukemia (B-ALL) cytotoxic T lymphocyte response against immunoglobulin heavy chain frame-derived nonapeptide.

METHODSThe peptide, QLVQSGAEV, containing IgHV1 frame region 3rd-11th amino acids (IgHV1(3-11)), was synthesized. IgHV1(3-11)-T2 binding tests were performed. HLA-A * 0201-positive normal peripheral blood mononuclear cells (PBMNC) were stimulated by IgHV1(3-11)-loaded antigen presenting cells three times at weekly intervals. HLA-A * 0201/IgHV1(3-11) tetramers were used to detect the proliferation of IgHV1(3-11)-specific CD8(+) T cells in the culture. Seven IgHV gene families of B-ALL patients were respectively amplified by PCR and the PCR products were sequenced to select IgHV1 and IgHV3 family monoallelic functional rearrangements. Among them, HLA-A * 0201 positive individuals were subsequently identified. Cytotoxicity of IgHV1(3-11)-specific CD8(+) T cells against HLA-A * 0201-positive IgHV1/IgHV3 family B-ALL cells was measured by MTT assay.

RESULTSThe synthesized IgHV1(3-11) up-regulated HLA-A * 0201 expression on T2 cell surface by 1.63-folds. The percentage of IgHV1(3-11)-specific CD8(+) T cells in HLA-A * 0201-positive normal PBMNC was increased from 1.64% after second stimulation to 82.57% after third stimulation. At effector: target ratio of 20:1, the killing rate of IgHV1(3-11)-specific CD8(+) T cells against IgHV1 family B-ALL cells was 18.24%, being 1.8-folds as that against IgHV3 family B-ALL cells (P = 0.01).

CONCLUSIONCytolytic T lymphocytes generated in vitro against immunoglobulin heavy chain frame-derived nonapeptides can kill B-ALL cells expressing these peptides.

Cells, Cultured ; Humans ; Immunoglobulin Heavy Chains ; immunology ; pharmacology ; Leukemia, B-Cell ; immunology ; pathology ; T-Lymphocytes, Cytotoxic ; drug effects ; immunology

This study was purposed to investigate the effect of prostaglandin E2 (PGE2) on proliferation of peripheral blood T lymphocytes, and to evaluate the regulatory role of PGE2 on immunological balance between Th1/Th2 and Tc1/Tc2 lymphocytes. The peripheral blood mononuclear cells (PBMNC) were stimulated by anti-human CD3 monoclonal antibody (mAb) and anti-human CD28 mAb, and were cultured in the presence of different concentration of PGE2 for 120 hours. The proliferation of peripheral blood T lymphocytes was assayed according to the manufacture protocol of BrdU Kit; the IFN-gamma and IL-4 levels in supernatants cultured for 24, 48, 72 and 120 hours were detected by ELISA; the ratios of CD4+IL-4+ T cells/CD4+ IFN-gamma+ T cells and CD8+IL-4+ T cell/CD8+IFN-gamma+ T cells were determined by flow cytometry. The cells cultured without PGE2 were used as control. The results indicated that (1) with the raising of concentration of PGE2, the inhibitory rate of T cell proliferation in vitro significantly increased (p=0.001). There was significant positive correlation between inhibitory rate of T cells and PGE2 concentration (correlation coefficient=0.889, p=0.000). (2) the difference between the IFN-gamma concentrations in supernatant cultured for 120 and 72 hours in test groups had no statistical significance (p=0.917). The IFN-gamma concentration increased continually with prolonging of culture time in control group (p=0.046). The IFN-gamma concentrations produced at different times in test group were significantly lower compared with those in control group (p<0.05). The IL-4 concentrations produced at different time had no significant change in test groups (p=0.400). The IL-4 concentration in 24 hours in control group was significantly higher than that at 48, 72 and 120 hours in control group (p=0.007, 0.003 and 0.002). After cultured for 24 hours the IL-4 concentration in test group was significantly lower than that in control group (p=0.037), but after cultured for 48, 72 and 120 hours, the IL-4 concentration in test group did not show statistical difference in comparison with control group (p>0.05). (3) the proportions of CD4+IFN-gamma+T cells in test group and in control group had no significant difference (p=0.767). The proportion of CD4+IL-4+T cells in test group was slightly higher than that in control group (p=0.051). The ratio of CD4+IL-4+T cells to CD4+IFN-gamma+ T cells in test group was significantly higher than that in control group (p=0.011). The proportions of CD8+IFN-gamma+ T cells in test group and in control group had no statistical difference (p=0.441). The proportion of CD8+IL-4+T cells in test group was significantly higher than that in control group (p=0.015). The ratio of CD8+IL-4+ T cells to CD8+IFN-gamma+ T cells in test group were obviously higher than that in control group(p=0.038). It is concluded that the PGE2 inhibits the proliferation of T lymphocytes in vitro. PGE2 influences the production of IFN-gamma and IL-4, and significantly influences peak appearance of IFN-gamma produced by T lymphocyte. PGE2 can continuously inhibit the production of IFN-gamma, but its continuous effect on IL-4 is no significant. PGE2 enhances the ratio of CD4+IL-4+T lymphocytes to CD4+IFN-gamma+T lymphocytes and the ratio of CD8+IL-4+T lymphocytes to CD8+IFN-gamma+T lymphocytes, and regulates development of T cells toward Th2/Tc2 cells.
Cell Proliferation ; drug effects ; Dinoprostone ; pharmacology ; Flow Cytometry ; Humans ; Lymphocyte Activation ; drug effects ; Lymphocyte Count ; T-Lymphocytes, Cytotoxic ; drug effects ; immunology ; Th1 Cells ; drug effects ; immunology ; Th2 Cells ; drug effects ; immunology

OBJECTIVETo investigate the specific antitumor immunity induced by antigen peptide mixture prepared from different T lymphocytic leukaemia cells and the cross-reaction among the mixtures of different cell lines.

METHODSAntigen peptide mixtures were prepared from different leukaemia cell lines and then bound with Hsp70 in vitro. The activation and proliferation of peripheral blood mononuclear cell (PBMC) were observed after the stimulation by different Hsp70-peptide complexes. The cytotoxicity of such activated PBMCs to different target cells was assayed.

RESULTSThe antigen peptides from different leukaemia cell lines were mixed ones, which could activate PBMC effectively with Hsp70 and stimulate the activated PBMC to proliferate. The proliferative PBMC had specific cytotoxicity to the corresponding leukaemia cells. To Hut-78 cell, Molt-4 cell and Jurkat cell, the cytotoxicity of PBMC activated by either Hut78-peptides or Molt-4-peptides was significantly stronger than that of PBMC activated by HL-60-peptides (P < 0.05). The cytotoxicity to Jurkat cell of PBMC activated by Hut78/Molt-4-peptides was significantly stronger than that of PBMC activated by Hut78-peptides or Molt-4-peptides alone (P < 0.05).

CONCLUSIONAntigen peptide mixture from T lymphocytic leukaemia cells is able to induce specific antitumor immunity. There is a cross-reactivity among antigen peptide mixtures from different T lymphocytic leukaemia cell lines, with the more crossed antigen peptides obtained from the mixtures of different antigen peptides from different T lymphocytic leukaemia cell lines, which suggests that the antigen peptide mixture with broad antigenic spectrum could possibly be prepared by using multiple leukaemia cell lines.

Antigens, Neoplasm ; metabolism ; pharmacology ; Cross Reactions ; HL-60 Cells ; HSP70 Heat-Shock Proteins ; metabolism ; Humans ; Leukemia, T-Cell ; immunology ; Leukocytes, Mononuclear ; cytology ; drug effects ; Peptides ; pharmacology ; T-Lymphocytes, Cytotoxic ; drug effects ; immunology ; Tumor Cells, Cultured ; chemistry ; immunology

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

OBJECTIVETo investigate the pathogenesis of cytotoxic T cell (CTL) dysfunction in patients with HCV infection.

METHODSBALB/c mice were immunized by subcutaneous injection of polypeptides from HCV core region, and the CTL activity of mouse spleen cells was detected by the LDH release test. Two polypeptides which can enhance CTL function and two polypeptides which can inhibit CTL function were selected and cross-combined. BALB/c mice were immunized using the combined polypeptides and the CTL activities were detected afterwards.

RESULTSCTL activity was inhibited by CPA9 (39-74 amino acids), CPB7 (67-76 amino acids) and CPB8 (71-80 amino acids), and promoted by CPA10 (5-23 amino acids), CPB6 (63-72 amino acids) and CPB2 (131-140 amino acids). Using single factor analysis of variance, the CTL activity in the mice could be enhanced by polypeptides from the HCV core region, CPB2+CPB8, CPB6+CPB8, respectively. There was no obvious difference between CPB2+CPB7, CPB6+CPB7 and negative control.

CONCLUSIONSCPA9, CPB7, and CPB8, the 3 polypeptides from HCV core region play an inhibition role and CPA10, CPB6, and CPB2 play an enhancement role in CTL activity in mice. The inhibition and enhancement functions of the polypeptides from HCV core region interact each other.

Animals ; Cytotoxicity Tests, Immunologic ; Cytotoxicity, Immunologic ; drug effects ; Mice ; Mice, Inbred BALB C ; Peptide Fragments ; administration & dosage ; immunology ; Spleen ; cytology ; drug effects ; immunology ; T-Lymphocytes, Cytotoxic ; cytology ; immunology ; Viral Core Proteins ; administration & dosage ; chemistry ; immunology

This study was purposed to investigate the effects of thalidomide on proliferation of peripheral blood mononuclear cells (PBMNCs), levels of lymphocyte subsets, secretion of cytokines and its killing activity, and to elucidate the immunoregulation mechanisms in treatment of multiple myeloma with thalidomide. The method of MTT was used to detect the effects of thalidomide on the proliferations and the cytotoxic activity of PBMNC; the flow cytometer was used to analyze the lymphocyte subsets; the ELISA was used to measure the concentrations of cytokines in culture supernatants. The results showed that thalidomide enhanced the proliferations of the CD8+ T, NK cells in PHA-stimulated PBMNC from healthy volunteers, increased the secretion of IL-6 significantly, and decreased the secretion of IFN-gamma, and the secretions of IL-2 and IL-10 were not affected. Compared with control group, at the same ratio of effectors to targets the thalidomide (5 microg/ml) could enhance the cytotoxic activity of PBMNC (P < 0.01), the cytotoxic activity was maximal when the ratio of effectors to targets was 40:1. It is concluded that thalidomide preferentially enhances the proliferations of CD8+ T, NK cells in PHA-stimulated PBMNC from healthy volunteers, and enhances the cytotoxic activity of PBMNC by increasing the secretion of IL-6 significantly, in short, thalidomide can exert anti-myeloma effects by increasing cellular immune function.
Adjuvants, Immunologic ; pharmacology ; Adult ; CD8-Positive T-Lymphocytes ; cytology ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cytokines ; biosynthesis ; Female ; Humans ; Immunity, Cellular ; drug effects ; Killer Cells, Natural ; cytology ; immunology ; Leukocytes, Mononuclear ; cytology ; drug effects ; immunology ; Lymphocyte Subsets ; drug effects ; immunology ; Male ; Middle Aged ; Multiple Myeloma ; pathology ; T-Lymphocytes, Cytotoxic ; drug effects ; Thalidomide ; pharmacology ; Tumor Cells, Cultured

Dendritic cells (DCs) are potent antigen-presenting cells. OK432 (Picibanil(R)) was introduced as a potent stimulator of DC maturation in combination with prostaglandin-E2 and interferon-alpha. We compared the efficacy of a DC-prostate cancer vaccine using early-mature DCs stimulated with OK432, PGE2 and INF-alpha (OPA) with that of vaccines using other methods. On days 3 or 7 of DC culture, TNF-alpha (T), TNF-alpha and LPS (TL) or OPA were employed as maturation stimulators. DU145 cells subjected to heat stress were hybridized with mature DCs using polyethyleneglycol. T cells were sensitized by the hybrids, and their proliferative and cytokine secretion activities and cytotoxicity were measured. The yields of early-mature DCs were higher, compared to yields at the conventional maturation time (P<0.05). In the early maturation setting, the mean fusion ratios, calculated from the fraction of dual-positive cells, were 13.3%, 18.6%, and 39.9%, respectively (P=0.051) in the T only, TL, and OPA-treated groups. The function of cytotoxic T cells, which were sensitized with the hybrids containing DCs matured early with OPA, was superior to that using other methods. The antitumor effects of DC-DU145 hybrids generated with DCs subjected to early maturation with the OPA may be superior to that of the hybrids using conventional maturation methods.
Cancer Vaccines/*immunology ; Cell Line, Tumor ; Dendritic Cells/cytology/drug effects/*immunology ; Dinoprostone/*pharmacology ; Humans ; Immunologic Factors/*pharmacology ; Interferon-alpha/*pharmacology ; Lipopolysaccharides/toxicity ; Male ; Neoplasms, Hormone-Dependent/*immunology ; Phenotype ; Picibanil/*pharmacology ; Prostatic Neoplasms/*immunology ; T-Lymphocytes, Cytotoxic/immunology

OBJECTIVETo investigate the cytotoxic effect of γδ T cells from osteosarcoma patients against interferon-γ (IFN-γ)-treated osteosarcoma cells in vitro.

METHODSHuman γδ T cells were amplified by zoledronate from peripheral blood cells of osteosarcoma patients. The expression of Fas on the osteosarcoma cells were measured by flow cytometry and quantitative real-time PCR analysis before and after IFN-γ treatment. The cytotoxicity of γδ T cells against osteosarcoma cells was evaluated with LDH assay.

RESULTSIFN-γ significantly enhanced the susceptibility of the osteosarcoma cell lines HOS and U2OS to the cytotoxicity of γDelta; T cells from osteosarcoma patients (P<0.01). IFN-γ obviously up-regulated the expression of Fas in HOS and U2OS cells (P<0.01). Anti-FasL mAb failed to inhibit the cytotoxicity of γδ T cells in untreated osteosarcoma targets (P>0.05), but significantly impaired γδ T cell cytotoxicity in IFN-γ pre-treated osteosarcoma targets (P<0.01).

CONCLUSIONIFN-γ can enhance the cytotoxic effect of human γδ T cells from osteosarcoma patients against osteosarcoma cells in vitro.

Bone Neoplasms ; metabolism ; Cell Line, Tumor ; Cytotoxicity, Immunologic ; Humans ; Interferon-gamma ; pharmacology ; Osteosarcoma ; immunology ; metabolism ; Receptors, Antigen, T-Cell, gamma-delta ; immunology ; T-Lymphocytes, Cytotoxic ; cytology ; drug effects ; immunology ; fas Receptor ; metabolism

OBJECTIVETo study whether dendritic cells (DCs) derived from the peripheral blood in chronic hepatitis B patients can induce specific T cell immune response.

METHODS(1)The subjects were divided into 3 groups: chronic hepatitis B group (CHB), acute hepatitis B group (AHB), and normal donor group (ND). The peripheral blood mononuclear cells (PBMCs) isolated from those subjects were stimulated with HBcAg 18 to 27 CTL epitope peptide, and intracellular cytokine staining (ICCS) was used for detecting IFN-gamma, IL-2 and TNF-alpha produced by CD8+ T cell. (2) DCs generated from PBMCs were pulsed with HBcAg 18 to 27 CTL epitope peptide, then were cocultured with autologous lymphocytes for 10 days to induce antigen-specific T cell, which was assessed by ICCS and cytotoxic assay.

RESULTS(1) The memory effect of the PBMCs from AHB group to HBcAg 18 to 27 CTL epitope peptide was stronger than that from CHB or ND group (t=2.508-3.305, P<0.05). (2)After lymphocytes were cocultured with DC treated with HBcAg 18 to 27 CTL epitope peptide, antigen-specific T cell effect was induced. And the killing rates were (57.0+/-23.0)%, (49.5+/-20.2)%, (21.8+/-12.9)% at the effector/target of 30:1, 10:1, 3:1, which were higher than that in control group.

CONCLUSIONSThe memory T cells against HBV antigen lacks in CHB patients. DCs from CHB patients pulsed with HBcAg 18 to 27 epitope peptide can induce HBV antigen-specific T cell, which can kill specific target cells and produce cytokines involved in virus clearance.

Adult ; CD8-Positive T-Lymphocytes ; immunology ; Cells, Cultured ; Dendritic Cells ; drug effects ; immunology ; virology ; Epitopes, T-Lymphocyte ; immunology ; Female ; Hepatitis B Core Antigens ; immunology ; Hepatitis B virus ; genetics ; immunology ; Hepatitis B, Chronic ; immunology ; Humans ; Leukocytes, Mononuclear ; immunology ; Male ; Middle Aged ; T-Lymphocytes, Cytotoxic ; immunology

The current modalities for treating cancer employ not only single but multiple approaches involving surgery, radiotherapy and chemotherapy. Unfortunately, the survival outcome is not promising even with these approaches. Alternative approaches for cancer therapy are now emerging. Immunotherapy is aiming at both increasing the power, and in redirecting the specificity of the patients' immune system to attack the tumor cells. Recently, many studies using tumor associated lymphocytes (TAL) isolated from malignant ascites cultured in a media containing interleukin-2 exhibit antitumor responses. IL-2 is a lymphokine produced by T-cells. It facilitates activation, sustained growth and rescue from apoptosis. Lately, newly developed IL-15 has also exhibited antitumor activity similar to IL-2. IL-15 is a newly described cytokine produced from monocytes-marcrophages and T-cells. It has a different molecular structure but it functions like IL-2 by binding to the IL-2R beta and gamma c chain. These antitumor responses are mediated by the cytotoxic T lymphocytes (CTL) that recognize the antigen in the context of the MHC molecules using the T cell receptors. CD8+-CTL recognize the peptide epitopes that are processed from the cellular proteins in the context of the MHC class I molecules. These peptides have a restricted length of 8-11 amino acids. The folate binding protein (FBP) is overexpressed in over 90% of ovarian and 20-50% in breast cancers. The FBP is the source of the antigenic peptides that are recognized by a number of these CTL-TAL, and is antigenic to both ovarian and breast cancer in vivo. To define the antitumor response of IL-15 and its' FBP immunogenicity, a peptide defining epitope E39 and E75 were presented by the PMBC derived dendritic cells (DC) from healthy donors isolated by the CD14 method to ovarian and breast CTL-TAL. Stimulating both ovarian and breast CTL- TAL by E39 or E75 pulsed DC (DC-E39, DC-E75), in the presence of IL-15 and IL-2 can rapidly enhance or induce the E39 or E75 specific CTL activity. The antitumor activities were measured by a chromium release assay for the tumor specific lysis activity using the ovarian and breast cancer cell lines. The tumor specific lysis activity for the ovarian TALs for IL-15 vs IL-2 were 28.6+/-3.9% and 30.3+/-3.2%, respectively and in the breast TALs, they were 14.8+/-3.1% vs 13.5+/-2.9%, respectively. Using autologous tumor cells, a slightly higher tumor specific lysis activity was obtained for the ovarian TALs cultured in IL-15 compared to IL-2 (72.0+/-8.2% vs 68.5+/-3.6%). However, for the breast TALs, they were 39.5+/-4.2% vs 41.5+/-3.3%, respectively. IL-15 is a newly developed cytokine that shows promising antitumor activity similar to IL-2. However, it requires lower dosage and is less toxic. Therefore, IL-15 might be a potential anticancer immunotherapeutic agent.
Breast Neoplasms/*immunology/therapy ; Carrier Proteins/*physiology ; Cells, Cultured ; Comparative Study ; Dendritic Cells/drug effects/*immunology ; Female ; Human ; Interleukin-15/*pharmacology ; Interleukin-2/*pharmacology ; Middle Age ; Ovarian Neoplasms/*immunology/therapy ; T-Lymphocytes, Cytotoxic/*immunology