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K Nomoto

Publications and source records attributed to K Nomoto.

At least 127 records · Page 7Linked to original sources

Expression of the melanoma antigen-encoding gene in human lung cancer.

BACKGROUND AND OBJECTIVES: We surveyed expression of melanoma antigen-encoding genes in lung cancer because of promising implications for immunotherapy. METHODS: We studied 57 human lung carcinoma specimens using the reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In the samples, the expression of melanoma antigen-encoding genes 1, 2, and 3 was observed in 9/43 (20.9%), 13/43 (30.2%), and 22/48 (45.8%), respectively. In 28 cases in which all three messenger RNAs were sought, 18 (64.3%) showed expression of at least one gene, 10 (35.7%) showed expression of two or three genes, and 10 (35.7%) were negative for all three genes. In a clinicopathologic analysis, melanoma antigen-encoding genes 1 and 3 were frequently expressed in squamous cell carcinomas (P = 0.0543) and in cases with regional lymph node metastasis (P = 0.0572), respectively. CONCLUSIONS: The high incidence of melanoma antigen-encoding gene expression in lung cancer indicates the possibility of a future specific immunotherapy for this disease.

Adenocarcinoma↗

Accumulation of human T lymphotropic virus type I-infected T cells in the salivary glands of patients with human T lymphotropic virus type I-associated Sjögren's syndrome.

OBJECTIVE: To clarify the involvement of human T lymphotropic virus type I (HTLV-I) in the pathogenesis of Sjogren's syndrome (SS). METHODS: In HTLV-I-seropositive patients with SS, HTLV-I proviral DNA in the labial salivary glands (SG) was detected by polymerase chain reaction (PCR) amplification of the extracted cellular DNA, and the localization in the SG was examined by in situ PCR hybridization. RESULTS: The cellular DNA extracted from the SG contained full HTLV-I proviral DNA, which was present in the nucleus of the infiltrating T cells, but not in either the SG epithelial cells or the acinar cells. Furthermore, the viral loads in the SG were approximately 8 times to 9 x 10(3) times higher than those in the peripheral blood mononuclear cells. CONCLUSION: Accumulation of HTLV-I-infected T cells in the SG suggests that HTLV-I likely causes the self-reactive T cells to proliferate, which, as a result, induces SS.

Adult↗

Heat shock proteins and the antitumor T cell response.

Heat shock proteins (HSP) have been shown to participate in the antitumor T cell response. First, HSP play a crucial role in the intracellular pathway for antigen processing where HSP can make complexes with a broad spectrum of cellular proteins and peptides through their chaperone functions. In this pathway, macrophages are required for processing the chaperoned peptides to make stable molecules with the major histocompatibility complex (MHC) class I molecules, even when HSP-peptide complexes are exogenously administered. Through this pathway, vaccination with HSP-peptide complexes is thus able to elicit the response of CD8+ T cells specific for the chaperoned peptides. These findings suggest an essential role of HSP in 'cross-priming' and their usefulness for antitumor vaccination with tumor peptides. Second, HSP have been suggested to be expressed on the cell surface by transformation and, in addition, to function as antigen-presenting molecules for double negative T cells. Third, HSP derived from tumor cells have reportedly been recognized by T cells with either T cell receptor (TCR)-alphabeta or TCR-gammadelta. These lines of evidence therefore indicate that HSP may be potentially promising target molecules for antitumor T cell immunotherapy.

Animals↗

Early-appearing tumor-infiltrating natural killer cells play an important role in the nitric oxide production of tumor-associated macrophages through their interferon production.

Both natural killer (NK) cells and macrophages are thought to be the main effectors responsible for early antitumor defense. In this study, we investigated the role of tumor-infiltrating NK cells in initiating nitric oxide (NO) production by tumor-associated macrophages (TAM). The in vivo depletion of NK cells prior to the i.p. inoculation of melanoma cells resulted in a significant decrease in the NO production of the TAM prepared from the peritoneal exudate cells (PEC). Such prior NK cell depletion also decreased the ability of TAM to show any antitumor activity in vitro. The addition of NG-monomethyl-L-arginine (Me-L-Arg) to the culture partially inhibited the ability of TAM to suppress the proliferation of melanoma cells and also decreased their cytolytic activity against melanoma cells. These results suggest that the TAM exhibited both cytostatic and cytolytic activities through their NO production. In an in vivo assay, the administration of Me-L-Arg permitted the more rapid growth of i.p. inoculated melanoma cells compared with the control. On the other hand, the decreased NO production of TAM, resulting from the prior NK cell depletion, was restored by the i.p. administration of interferon gamma (IFN gamma). In addition, the in vivo administration of anti-IFN gamma mAb into mice inoculated i.p. with melanoma cells also significantly decreased the NO production of TAM in peritoneal exudate cells. Furthermore, the tumor-infiltrating NK cells produced a considerable level of IFN gamma. Overall, these results indicate that early-appearing tumor-infiltrating NK cells play an important role in the NO production of TAM through their IFN gamma production.

Animals↗

A novel glycoprotein obtained from Chlorella vulgaris strain CK22 shows antimetastatic immunopotentiation.

A glycoprotein extract (CVS), derived from the unicellular green alga Chlorella vulgaris, strain CK22, exhibited a pronounced antitumor effect against both spontaneous and experimentally induced metastasis in mice. Inhibition of tumor metastasis was enhanced when intratumor administration of CVS was followed by s.c. injection of CVS. Anti-metastatic immunopotentiation was observed in euthymic mice, but not in athymic nude mice. The antitumor activity of CVS was reflected in antigen-specific, T-cell-mediated immunity. Both CD4 and CD8 T cells contributed to the antimetastatic effects, as shown by in vivo depletion experiments with anti-T-cell subset antibodies. Furthermore, CVS caused the recruitment of T cells to the regional lymph nodes and their proliferation in these organs. The CD4-positive population, following CVS injection at the time of tumor rechallenge, displayed a pronounced increase in the proportion of T cells that were CD18 bright, CD44 bright, CD25+, CD54+, CD69+ or CD71+ in the lymph nodes. Thus, CVS induces T cell activation in peripheral lymph nodes in tumor-bearing mice. We conclude that CVS augments antimetastatic immunity through T cell activation in lymphoid organs and enhances recruitment of these cells to the tumor sites. Presurgical treatment with CVS might prevent metastasis or tumor progression.

Animals↗

Antitumor vaccination effect of dendritic cells can be augmented by locally utilizing Th1-type cytokines from OK432-reactive CD4+ T cells.

In order to enhance the antitumor vaccination effect of dendritic cells (DC) pulsed with class I tumor peptide, we tried to utilize the local cytokine help of CD4+ T cells reactive to a streptococcal preparation OK432. DC were prepared from murine bone marrow cells by culture with both granulocyte/macrophage-colony-stimulating factor and interleukin(IL)-4. The peritumoral injections of OK432 induced OK432-reactive CD4+ T cells in the draining lymph nodes, and their in vitro production of interferon gamma was thus significantly enhanced by restimulation with OK432-pulsed DC. In addition, anti-P815 mastocytoma cytotoxic T lymphocytes were generated from the in vivo OK432-treated P815-draining lymph node cells only when the lymph node cells were restimulated in vitro with the DC pulsed with both P1A peptide and OK432. Moreover, the peritumoral injections of OK432 and the subsequent vaccination of the DC, pulsed with both OK432 and P1A peptide, significantly suppressed the growth of s.c. inoculated P815. Interestingly, a significant level of IL-12 was detected in the coculture supernatant of both OK432-pulsed DC and OK432-reactive CD4+ T cells. Collectively, our results suggest that the antitumor vaccination effect of DC pulsed with class I tumor peptide could thus be effectively augmented by locally utilizing the Th1-type cytokines from OK432-reactive CD4+ T cells.

Animals↗

Characterization of B16 melanoma-specific cytotoxic T lymphocytes.

A B16 melanoma-specific CD8+ T cell line (AB1) was established from the spleen cells of C57BL/6 mice cured of B16 melanoma with interleukin (IL)-12 treatment. The AB1 line exclusively used T cell receptor Vbeta11. The AB1 cells exhibited a cytolytic activity against both syngeneic B16 melanoma and allogeneic P815 mastocytoma, whereas a cold inhibition assay revealed specificity of the AB1 cells against B16 melanoma. Their lostability to kill a class I loss variant of B16 melanoma was restored by the transfection of H-2Kb gene. In addition, their interferon (IFN)-gamma production was significantly suppressed by the addition of anti-H-2Kb monoclonal antibody, and RT-PCR analysis showed that the AB1 line expressed the mRNA encoding IFN-gamma, but not IL-4 or IL-10. The experiment using synthetic peptides of tyrosinase-related protein-2 (TRP-2) revealed that the AB1 cells could recognize TRP-2(181-188) peptide. Moreover, the AB1 cells showed an in vivo antitumor effect against established pulmonary metastases of B16 melanoma. Overall, these results indicate that the Tc1-type Vbeta11+ AB1 cells exert an antitumor activity against syngeneic B16 melanoma through recognition of TRP-2(181-188) peptide in an H-2Kb-restricted manner.

Animals↗

Antitumor response of regional lymph node lymphocytes in human lung cancer.

We recently reported that regional lymph node lymphocytes (RLNL) from patients with primary lung cancer were in a more highly activated state than peripheral blood lymphocytes (PBL) when the activation-related molecules were studied by FACS analysis. To identify whether or not RLNL had the ability to respond to autologous tumor cells (AT), in the present study a mixed lymphocyte tumor cell reaction (MLTR) either with or without recombinant interleukin 2 (rlL-2) was performed in 41 cases with primary lung cancer. Significant proliferative responses to AT were found in RLNL from 20 of 41 cases (48.8%) without IL-2, and in 23 of 41 cases (56.1%) with IL-2. On the other hand, such responses were observed in the PBL from 8 of 30 cases (26.7%) without IL-2, and from 11 of 30 cases (36.7%) with IL-2. No significant correlation between MLTR and such clinical factors as tumor size, metastasis to lymph node, histology and stage of the disease was found. To further analyze the anti-AT response of RLNL, the cytokine production of RLNL was investigated after stimulation by AT. An increase in interferon-gamma (IFN-gamma) production was observed in RLNL with a positive reaction of MLTR, while no such increase was found in PBL. Finally, to elucidate whether the expression of MHC class II molecules was a key point in MLTR, tumor cells in primary lesions were examined for the expression of MHC class II by immunohistochemical staining, and the blocking assay of MLTR was performed with anti-MHC class II monoclonal antibody. Data suggested that there was a positive correlation between MHC class II expression of the tumor and MLTR and that MLTR were partially blocked by anti-MHC class II monoclonal antibody. These results demonstrated that RLNL were in a more highly activated state against AT than were PBL, and this finding is considered to be helpful in enhancing our understanding of the role of RLNL in lung cancer patients.

Antibodies, Monoclonal↗

Effect of a traditional Chinese medicine, Bu-zhong-yi-qi-tang on the protection against an oral infection with Listeria monocytogenes.

The protective effect against an oral infection with Listeria monocytogenes was observed in BALB/c mice who were orally administered a traditional Chinese medicine, Bu-zhong-yi-qi-tang (Japanese name: Hochu-ekki-to, HOT) daily for 7 days. Bacterial numbers in the Peyer's patch (PP) at 18 h, in the mesenteric lymph nodes (MLN) at 18 h, 1 day and 3 days and in the liver at 3 days after infection were significantly suppressed in HOT-treated mice, although there was no difference in the bacterial number in the small intestinal contents. The enhanced bactericidal activities of PP and liver macrophages by pretreatments of HOT were observed. The protective effect of HOT was not observed in athymic nu/nu and IFN-gamma deficient mice. The administration of HOT increased IFN-gamma-producing cells in the intestinal intraepithelial lymphocytes (IEL) but did not in the PP, MLN and liver. HOT exerts effects mainly on CD8alphabeta+ IEL which are thymus-dependent, and induced IFN-gamma production from their cells. These results suggest that HOT acts on the gut-associated lymphoid tissues and induces IFN-gamma from CD8alphabeta+ IEL, which activates PP and liver macrophages and consequently the resistance to L. monocytogenes is augmented in the mice.

Animals↗

Direct action of a protein-bound polysaccharide, PSK, on transforming growth factor-beta.

We investigated the action of a protein-bound polysaccharide, PSK, on transforming growth factor-beta (TGF-beta). (1) In in vitro-mixed culture of peripheral blood mononuclear cells (PBMC) from healthy human and mitomycin C-treated human colon cancer cells, PSK or polyclonal antibody to TGF-beta significantly enhanced incorporation of 3H-thymidine into PBMC, and apparently decreased TGF-beta1 levels of acid-treated culture supernatant. (2) PSK or the antibody interfered with the quantitation by enzyme immunoassay of TGF-beta1 in acid-treated supernatant of the mixed culture. (3) PSK was suggested to form a complex with 125I-human recombinant TGF-beta1 standard, when changes in molecular weight of radioactivities were assessed by gel filtration. Recombinant human TGF-beta1 inhibited growth of mink lung epithelial cell line Mv1Lu and promoted collagen synthesis in rat kidney fibroblast cell line NRK49F, but the complex did not have such activities. (4) In addition to TGF-beta1, PSK bound with TGF-beta2 and platelet-derived growth factor; however, PSK did not bind with 22 other species of cytokines and growth factors. (5) Protein moiety of PSK is suggested to play an important role in the expression of the activity. These results suggest that PSK modulates the biological activity of TGF-beta1 by binding to its active form.

Animals↗

Vaccination with activated B cells pulsed with tumor-lysates can induce tumor-specific CD4+ T cells in vivo.

Activated B cells, pulsed with tumor-lysates, were examined for their potential to induce tumor-specific CD4+ T cells in vivo, MH2 cells, which are CD4+ T cells and can also recognize purified protein derivative from mycobacterium tuberculosis (PPD), showed a proliferative response in the presence of both syngeneic activated B cells and PPD in a major histocompatibility complex class II-restricted manner. For B cells to function as efficient antigen presenting cells, they need to be activated. Both irradiation and several inhibitors for antigen-processing were observed to block the antigen-presenting ability of activated B cells. Based in these findings, the possibility of anti-tumor vaccination with activated B cells was thus investigated. The spleen cells from mice, which were immunized with activated B cells pulsed with B16 melanoma-lysates, produced a higher level of interferon (IFN)-gamma than those from mice, which were immunized with either non-pulsed activated B cells or the tumor-lysates alone, after in vitro restimulation. This IFN-gamma production was also dependent on the CD4+ T cells. Moreover, the splenic CD4+ T cells in such mice were suggested to increase their ability to generate B16 melanoma-specific cytotoxic T lymphocytes after in vitro restimulation. Even more importantly, immunization with B16 melanoma lysate-pulsed activated B cells elicited a protective immunity against B16 melanoma at rechallenge. Collectively, these results indicate that an anti-tumor effect could be induced by immunization with activated B cells, pulsed with the tumor-lysates, by eliciting tumor-specific IFN-gamma producing CD4+ T cells in vivo.

Animals↗

Combined treatments with Ninjin-youei-to (Ren-shen-yang-rong-tang) plus a suboptimal dose of prednisolone on autoimmune nephritis in MRL/lpr mice.

MRL/lpr mice suffer from a systemic lupus erythematosus-like autoimmune disease. We studied the effects of oral treatments with Ninjin-youei-to (NYT, Ren-shen-yang-rong-tang, 1000 mg/kg/day), a suboptimal dose (2 mg/kg/day) of prednisolone(PSL) and their combination on nephritis in MRL/lpr mice. Treatments with NYT or PSL alone inhibited the development of proteinuria and prolonged survival. The combined treatment reduced the incidence of proteinuria and prolonged survival. In histological analysis, NYT treatments decreased the degree of mesangial proliferative glomerulonephritis and infiltration of mononuclear cells in the kidneys. PSL treatment was effective in reducing periglomerular nephritis and vasculitis in addition to such effects as NYT and NYT plus PSL treatment was more effective than PSL alone. The active form of TGF-beta was reduced in NYT and PSL-treated mouse serum, and the combined treatments further suppressed it. However, the treatment with NYT alone did not induce a decrease in the latent form of TGF-beta. The effect of NYT can be assumed to be different from an immunosuppressive effect of PSL. Therefore, the combined treatment with NYT and PSL can be expected to be more useful for the therapy of autoimmune disease such as nephritis, compared with NYT or PSL alone treatments.

Animals↗

Involvement of both donor cytotoxic T lymphocytes and host NK1.1+ T cells in the thymic atrophy of mice suffering from acute graft-versus-host disease.

It has been reported that a dramatic decrease in the number of thymocytes (thymic atrophy) in mice suffering from acute graft-versus-host disease (GVHD) is ascribed to glucocorticoids. In this study, we examined the possibility that cellular immune responses may thus be involved in thymic atrophy. In contrast to chronic GVHD mice, acute GVHD (C57BL/6 X DBA/2) F1 (BDF1) hybrid mice, which were injected intravenously with both spleen and lymph node cells from C57BL/6 mice, showed a dramatic decrease in the number of CD4 CD8 double-positive thymocytes 2 or 3 weeks after the induction of GVHD. A flow cytometric analysis revealed the donor-derived T cells with either CD4 or CD8 molecules to infiltrate the thymus of the mice undergoing acute GVHD for 10 days. In a cytolytic assay, such thymus-containing cells exhibited a cytolytic activity specific to the host cells. In addition, anti-H-2d cytolytic T cells showed a high level of cytolytic activity against BDF1 (H-2bXd) thymocytes, whereas they also showed a low level of cytolytic activity against C57BL/6 (H-2b) thymocytes, thus suggesting that the thymus-infiltrating donor-derived T cells killed the host thymocytes through both anti-H-2d-specific and non-specific mechanisms. Interestingly, a flow cytometric analysis revealed both the percentage and the absolute cell number of host-derived NK1.1+ CD3+ cells to increase in the thymus of mice suffering from acute GVHD for 10 days. In addition, they also showed the cytolytic activity against YAC-1 cells and the mRNA expression of interleukin-12 (IL-12) in the thymus to be also significantly augmented on day 7 after the induction of acute GVHD. Collectively, our results indicate that the cellular immune responses such as donor cytotoxic T lymphocytes and host NK1.1+ T cells are therefore involved in the thymic atrophy of mice suffering from acute GVHD.

Acute Disease↗

Gamma delta T cells in infection-induced and autoimmune-induced testicular inflammation.

In a previous report, we investigated inflammatory responses induced by injecting Listeria monocytogenes into one testis of a mouse. We demonstrated that the contralateral testis also developed an orchitis despite the absence of bacteria, indicating that the inflammation on the uninfected, contralateral side was of autoimmune character. In both infected and autoimmune testes, gammadelta and alphabeta T cells infiltrated during the inflammation. In this paper, we present the data of a comparison of the character of gammadelta T cells of the infected and autoimmune testes. In both testes, gammadelta T cells appeared to be activated, as assessed by high CD44 and low l-selectin expression. Analysis of T-cell receptor (TCR) usage in both inflammation types revealed the same gammadelta TCR repertoire. Finally, the semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) demonstrated that gammadelta T cells in both types of inflammation were capable of producing interleukin-2 (IL-2), IL-4, interferon-gamma (IFN-gamma), IL-10 and transforming growth factor-beta (TGF-beta). These results imply that gammadelta T cells present in infected-induced and autoimmunity-induced inflammation have the same characteristics and could work as immunoregulatory cells.

Animals↗

The role of gammadelta T cells in induction of bacterial antigen-specific protective CD8+ cytotoxic T cells in immune response against the intracellular bacteria Listeria monocytogenes.

The role of T-cell receptor (TCR) gammadelta T cells in the induction of protective TCR alphabeta T cells against infection by the intracellular bacteria Listeria monocytogenes was analysed. We found that depletion of gammadelta T cells by anti-TCR delta monoclonal antibody treatment before intravenous immunization of mice with a sublethal dose of viable L. monocytogenes resulted in reduction of protection against secondary challenge infection in the immunized mice. The gammadelta T-cell depletion also reduced induction of protective alphabeta T cells capable of transferring the protection against challenge infection of L. monocytogenes into naive mice. Furthermore, the protective T cells that were affected by the gammadelta T-cell depletion were suggested to be CD8+ cytotoxic T cells rather than CD4+ T cells by the following observations. First, induction of cytotoxic T lymphocytes specific to a L. monocytogenes-derived H-2Kd-restricted peptide (listeriolysin O 91-99) was significantly suppressed by gammadelta T-cell depletion before immunization. Second, gammadelta T-cell depletion did not affect cytokine production and proliferation of T cells from immunized mice in response to in vitro stimulation with heat-killed Listeria which preferentially stimulates CD4+ T cells. Third, CD8+ alphabeta T cells from control immunized mice transferred protection against infection of L. monocytogenes into naive mice but only a limited degree of protection was transferred by CD8+ T cells from the gammadelta T-cell-depleted immunized mice; and fourth, CD4+ alphabeta T cells from the gammadelta T-cell-depleted mice transferred a similar level of protection as those from the control immunized mice. All these results suggest that gammadelta T cells participate in establishment of protective immunity against intracellular bacteria by supporting priming of bacterial antigen-specific CD8+ cytotoxic T cells.

Adoptive Transfer↗

Role of macrophages in acute murine cytomegalovirus infection.

It has been recognized that macrophages play an important role in controlling virus infection in experimental animal models. To evaluate the role of macrophages in acute murine cytomegalovirus infection, macrophages in the spleen and the liver were eliminated by an intravenous injection of liposomes containing a cytolytic agent, dichloromethylene diphosphonate. The depletion of macrophages led to a significant increase of virus titer in the spleen and lungs in both susceptible BALB/c and resistant C57BL/6 mice during the first three days after intravenous infection. In the spleen, the increase of virus titer in macrophage-depleted BALB/c mice was much greater than that in NK cell-depleted mice. These results suggest that macrophages contribute to protection mainly by the mechanisms which are independent of NK cells during the first three days after infection. The increase of virus titer in macrophage-depleted C57BL/6 mice was as great as that in NK cell-depleted mice because of the high contribution of NK cells to protection in C57BL/6 mice. In the liver in both strains of mice, the effects of macrophage depletion on virus titer were not as much as those in the spleen and lungs. Furthermore, the local depletion of peritoneal macrophages resulted in a great increase of virus titer in the spleen at three days after intraperitoneal infection. We conclude that macrophages greatly contribute to decreasing the virus load in some organs possibly through either or both intrinsic and extrinsic mechanisms in the early phase of primary infection with murine cytomegalovirus.

Acute Disease↗

Autologous tumor-specific cytotoxic T lymphocytes in a patient with lung adenocarcinoma: implications of the shared antigens expressed in HLA-A24 lung cancer cells.

Human lung adenocarcinoma-specific cytotoxic T lymphocytes (CTL) were generated by multiple stimulations with autologous tumor cells (named A110L) from regional lymph node lymphocytes and tumor-infiltrating lymphocytes expanded by solid-phase anti-CD3 monoclonal antibody (mAb) and recombinant interleukin-2. The CTL lysed A110L but failed to kill either autologous B lymphocytes immortalized by the Epstein-Barr virus or K562. The killing activity of the CTL against autologous A110L was inhibited by anti-MHC class I mAb (W6/32), but not by anti-MHC class II mAb. The CTL produced interferon-gamma and GM-CSF in response to A110L and the production was completely blocked by the addition of anti-MHC class I mAb. The HLA type of the CTL was HLA-A2/A24, B52/B54, Cw1/-. Allele-specific deletion of HLA-A2 molecules was observed in A110L by staining with anti-HLA-A2 mAb. A partial blocking effect on the cytokine production from the CTL was also obtained with anti-CD8, and anti-HLA-A24 mAbs, but not with anti-MHC class II, anti-CD4 and anti-HLA-A2 mAbs. To analyze further the mechanism of antigen recognition by the CTL, the cross reactivity of the CTL against several HLA-A locus-matched (HLA-A24+) and mismatched allogeneic tumor cells (HLA-A24-) was investigated. The A110L-specific CTL showed a weak but significant cytotoxicity against some HLA-A24 positive lung cancer cell lines, such as Sq-1 (HLA-A11/A24, squamous cell carcinoma) and PC-9 (HLA-A2/A24, adenocarcinoma), but failed to kill HLA-A locus-mismatched allogeneic tumors. This cross reactivity of the CTL against Sq-1 and PC-9 was blocked by anti-MHC class I mAb. These results thus demonstrate that shared common tumor antigens might exist among lung cancer cells in the context of HLA-A24.

Adenocarcinoma↗