Research Interests: Biology, Life Sciences, Medicine, Transgenic Mice, Hematopoietic Stem Cells, and 13 moreCell Differentiation, Humans, Mice, Female, Animals, Blood, CD, Clinical Sciences, Medicine and Health Sciences, nod, Human leukocyte antigen, Cardiovascular medicine and haematology, and Paediatrics and reproductive medicine
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Research Interests: Biology, Virology, Medicine, Humans, Clinical Sciences, and 4 moreCTL, Protein Expression, Retrovirology, and Antigen
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Human cytotoxic T lymphocyte (CTL) clones directed against herpes simplex virus (HSV)-infected cells were generated after stimulation of peripheral blood lymphocytes (PBL) with HSV type 1 (HSV-1) and HSV type 2 (HSV-2). These CTL clones... more
Human cytotoxic T lymphocyte (CTL) clones directed against herpes simplex virus (HSV)-infected cells were generated after stimulation of peripheral blood lymphocytes (PBL) with HSV type 1 (HSV-1) and HSV type 2 (HSV-2). These CTL clones were studied with regard to HSV type specificity and with regard to whether they also express helper cell activity. Some clones, generated after stimulation with HSV-1, were cytotoxic for autologous cells infected with either HSV-1 or HSV-2 ("HSV type common clones"), whereas other clones lysed HSV-1-infected cells only ("type-specific clones"). Similarly, after HSV-2 stimulation, both HSV-2 specific and HSV type common clones were obtained, indicating the heterogeneity of human cytotoxic T cells to HSV. All CTL clones tested were found to be bifunctional in that they also proliferated in response to stimulation with HSV. The HSV type specificity of the proliferative response was identical to that of the cytotoxic activity of the ...
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adenovirus vector containing the CD4 gene. myeloid cell lines transduced with an Human herpesvirus 7 infection of lymphoid and
Although it is well known that CD8(+) cytotoxic T lymphocytes (CTLs) play an important role in the suppression of cancer cell growth, the significance of CD4(+) CTLs in resistance to cancer is obscure. In an attempt to elucidate the role... more
Although it is well known that CD8(+) cytotoxic T lymphocytes (CTLs) play an important role in the suppression of cancer cell growth, the significance of CD4(+) CTLs in resistance to cancer is obscure. In an attempt to elucidate the role of CD4(+) CTLs in immunosurveillance of chronic myelogenous leukemia (CML), we examined the immunologic functions of bcr-abl b3a2 fusion peptide-specific CD4(+) CTL clones. Seven CD4(+) T-cell clones that responded to stimulation with b3a2 peptide, but not with b2a2 peptide or physiological counterparts bcr b3b4 and abl 1A-a2 peptides, were established from two healthy individuals. Restriction elements of these clones were HLA-DRB1*0901. These CD4(+) T-cell clones exhibited b3a2 peptide-specific and HLA-DRB1*0901-restricted cytotoxicity and produced interleukin-3 (IL-3), IL-4, IL-10, interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor in response to bcr-abl peptide stimulation, indicating they were Th0...
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It has been reported recently that CD4 is a major component of the receptor for human herpesvirus 7 (HHV-7), which has been newly identified as a T-lymphotropic virus. To investigate further the role of CD4 in HHV-7 infection, we examined... more
It has been reported recently that CD4 is a major component of the receptor for human herpesvirus 7 (HHV-7), which has been newly identified as a T-lymphotropic virus. To investigate further the role of CD4 in HHV-7 infection, we examined the susceptibility to HHV-7 infection of various CD4-negative or weakly positive cell lines into which the cDNA for CD4 was transferred using an adenovirus vector (Adex1CACD4). Of 13 cell lines transduced with Adex1CACD4, including T-lymphoid, B-lymphoid, monocytoid, and myeloid cell lines, one T-lymphoid cell line, one monocytoid cell line, and two cell lines established from the blast crisis of chronic myelogenous leukemia showed high susceptibility to HHV-7 infection. Taken together with the results of previous studies, these data suggest strongly that CD4 is a major component of the binding receptor for HHV-7. This study also shows that HHV-7 may be able to infect CD4-positive hematopoietic precursor cells as well as T lymphocytes.
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It has been reported that reactivation of human herpesvirus-6 (HHV-6) causes a failure of hematopoiesis. To clarify the mechanisms of bone marrow suppression induced by HHV-6 infection, it is necessary to establish an in vitro model of... more
It has been reported that reactivation of human herpesvirus-6 (HHV-6) causes a failure of hematopoiesis. To clarify the mechanisms of bone marrow suppression induced by HHV-6 infection, it is necessary to establish an in vitro model of HHV-6 infection in hematopoietic progenitor cells. We have established two novel Philadelphia chromosome–positive myeloid cell lines, SAS413 and SAS527, which possess different hematologic characteristics and show distinct susceptibility to infection by HHV-6, from a patient with blast crisis of chronic myelogenous leukemia (CML). HHV-6 subgroup A (HHV-6A) showed marked replication in SAS413, forming syncytia and inducing cell lysis in short-term culture. On the other hand, HHV-6A–inoculated SAS527 continued to proliferate without cell lysis and only a few cells showed HHV-6 antigen expression. In contrast to HHV-6A infection, inoculation with HHV-6 subgroup B (HHV-6B) did not induce any cytopathic effect (CPE) or viral antigen expression in either of...
Research Interests: Biology, Virology, Medicine, Cell Culture, Hematopoiesis, and 15 moreHematopoietic Stem Cells, Cell line, Humans, Blood, Male, Polymerase Chain Reaction, Haematopoiesis, Clinical Sciences, Adult, Latency, Antigen, Cardiovascular medicine and haematology, Paediatrics and reproductive medicine, Neoplastic Stem Cells, and Macho
While menin plays an important role in preventing T-cell dysfunction, such as senescence and exhaustion, the regulatory mechanisms remain unclear. We found that menin prevents the induction of dysfunction in activated CD8 T cells by... more
While menin plays an important role in preventing T-cell dysfunction, such as senescence and exhaustion, the regulatory mechanisms remain unclear. We found that menin prevents the induction of dysfunction in activated CD8 T cells by restricting the cellular metabolism. mTOR complex 1 (mTORC1) signaling, glycolysis, and glutaminolysis are augmented by menin deficiency. Rapamycin treatment prevents CD8 T-cell dysfunction in menin-deficient CD8 T cells. Limited glutamine availability also prevents CD8 T-cell dysfunction induced by menin deficiency, and its inhibitory effect is antagonized by α-ketoglutarate (α-KG), an intermediate metabolite of glutaminolysis. α-KG-dependent histone H3K27 demethylation seems to be involved in the dysfunction in menin-deficient CD8 T cells. We also found that α-KG activates mTORC1-dependent central carbon metabolism. These findings suggest that menin maintains the T-cell functions by limiting mTORC 1 activity and subsequent cellular metabolism.
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Although the methylation status of histone H3K27 plays a critical role in CD4+ T cell differentiation and its function, the role of Utx histone H3K27 demethylase in the CD8+ T cell–dependent immune response remains unclear. We therefore... more
Although the methylation status of histone H3K27 plays a critical role in CD4+ T cell differentiation and its function, the role of Utx histone H3K27 demethylase in the CD8+ T cell–dependent immune response remains unclear. We therefore generated T cell–specific Utxflox/flox Cd4-Cre Tg (Utx KO) mice to determine the role of Utx in CD8+ T cells. Wild-type (WT) and Utx KO mice were infected with Listeria monocytogenes expressing OVA to analyze the immune response of Ag-specific CD8+ T cells. There was no significant difference in the number of Ag-specific CD8+ T cells upon primary infection between WT and Utx KO mice. However, Utx deficiency resulted in more Ag-specific CD8+ T cells upon secondary infection. Adoptive transfer of Utx KO CD8+ T cells resulted in a larger number of memory cells in the primary response than in WT. We observed a decreased gene expression of effector-associated transcription factors, including Prdm1 encoding Blimp1, in Utx KO CD8+ T cells. We confirmed that...
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Gfi1 plays an important role in the development and maintenance of many hematopoietic linage cells. However, the impact of Gfi1-deficiency on the iNKT cell differentiation remains unclear. We herein demonstrate a critical role of Gfi1 in... more
Gfi1 plays an important role in the development and maintenance of many hematopoietic linage cells. However, the impact of Gfi1-deficiency on the iNKT cell differentiation remains unclear. We herein demonstrate a critical role of Gfi1 in regulating the development of iNKT cell subsets. In the thymus of T cell-specific Gfi1-deficient mice, iNKT cells normally developed up to stage 2, while the number of stage 3 NK1.1pos iNKT cells was significantly reduced. Furthermore, CD4pos iNKT cells were selectively reduced in the peripheral organs of T cell-specific Gfi1-deficient mice. The α-GalCer-dependent production of IFN-γand Th2 cytokines, but not IL-17A, was severely reduced in T cell-specific Gfi1-deficient mice. In addition, a reduction of the α-GalCer-induced anti-tumor activity was observed in Gfi1-deficient mice. These findings demonstrate the important role of Gfi1 in regulating the development and function of NKT1- and NKT2-type iNKT cell subsets.
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Research Interests: Genetics, Functional Analysis, Immunology, Flow Cytometry, Biology, and 15 moreJapan, Cytotoxicity, Early Childhood, Family history, Humans, Child, Female, Male, Infant, CTL, Genetic Analysis, Hemophagocytic Lymphohistiocytosis, DNA mutational analysis, degranulation, and Genetic predisposition to disease
Human herpesvirus 6 (HHV-6) has a tropism for T lymphocytes and monocytes/macrophages, suggesting that HHV-6 infection affects the immunosurveillance system. In the present study, we investigated the HHV-6-induced phenotypic and... more
Human herpesvirus 6 (HHV-6) has a tropism for T lymphocytes and monocytes/macrophages, suggesting that HHV-6 infection affects the immunosurveillance system. In the present study, we investigated the HHV-6-induced phenotypic and functional alterations of dendritic cells (DCs), which are professional antigen-presenting cells. HHV-6 infection of monocyte-derived immature DCs appeared to induce the up-regulation of CD80, CD83, CD86, and HLA class I and class II molecules, suggesting that HHV-6 infection induces the maturation of DCs. In addition, the antigen capture capacity of DCs was found to decrease following infection with HHV-6. In contrast to up-regulation of mature-DC-associated surface molecules on HHV-6-infected DCs, their capacity for presentation of alloantigens and exogenous virus antigens to T lymphocytes decreased significantly from that of uninfected DCs. In contrast, there appeared to be no reduction in the capacity for presentation of an HLA class II-binding peptide t...
Research Interests: Immunology, Flow Cytometry, Biology, Virology, Medicine, and 14 moreDendritic Cells, Biological Sciences, Humans, Endocytosis, Antigen Processing, Antigen Presentation, Dendritic cell, Phenotype, CD, Tumor necrosis factor-alpha, Immunophenotyping, Immunoglobulins, Antigen, and Medical and Health Sciences
We have recently reported that down-regulation of CXC chemokine receptor (CXCR) 4 in CD4+ T lymphocytes is induced by human herpesvirus (HHV) 6 infection. In this study, we further studied the mechanisms of HHV-6-induced CXCR4... more
We have recently reported that down-regulation of CXC chemokine receptor (CXCR) 4 in CD4+ T lymphocytes is induced by human herpesvirus (HHV) 6 infection. In this study, we further studied the mechanisms of HHV-6-induced CXCR4 down-regulation, focusing on the regulation of CXCR4 transcription. Down-regulation of CXCR4 transcription was detected in HHV-6A-infected JJHAN and HHV-6B-infected MT-4 cell lines, as we had previously reported for HHV-6-infected peripheral blood CD4+ T lymphocytes. Luciferase assays revealed that a YY1-binding site around −320 relative to the transcription start site is important for down-regulation of CXCR4 transcription in HHV-6-infected cells. The binding activity of YY1, which is a repressor of CXCR4 transcription, to the CXCR4 promoter appeared to significantly increase in HHV-6-infected cells compared with the binding activity in mock-infected cells. Immunoprecipitation assays showed that in HHV-6-infected cells association of c-Myc with YY1 was decrea...
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Here we report that a new nonobese diabetic/severe combined immunodeficient (NOD/SCID) mouse line harboring a complete null mutation of the common cytokine receptor γ chain (NOD/SCID/interleukin 2 receptor [IL2r] γnull) efficiently... more
Here we report that a new nonobese diabetic/severe combined immunodeficient (NOD/SCID) mouse line harboring a complete null mutation of the common cytokine receptor γ chain (NOD/SCID/interleukin 2 receptor [IL2r] γnull) efficiently supports development of functional human hemato-lymphopoiesis. Purified human (h) CD34+ or hCD34+hCD38– cord blood (CB) cells were transplanted into NOD/SCID/IL2rγnull newborns via a facial vein. In all recipients injected with 105 hCD34+ or 2 × 104 hCD34+hCD38– CB cells, human hematopoietic cells were reconstituted at approximately 70% of chimerisms. A high percentage of the human hematopoietic cell chimerism persisted for more than 24 weeks after transplantation, and hCD34+ bone marrow grafts of primary recipients could reconstitute hematopoiesis in secondary NOD/SCID/IL2rγnull recipients, suggesting that this system can support self-renewal of human hematopoietic stem cells. hCD34+hCD38– CB cells differentiated into mature blood cells, including myelom...
Research Interests: Biology, Cell Differentiation, Humans, Cord Blood, Animals, and 15 moreBlood, Dendritic cell, Bone marrow, Haematopoiesis, Clinical Sciences, Immune system, Blood cells, Bone Marrow Cells, Hematopoietic Stem Cell, Experimental Model, Hematopoietic Stem Cell Transplantation, Human leukocyte antigen, Cardiovascular medicine and haematology, Human Immune System, and B cell
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Research Interests: Immunology, Medicine, In Situ Hybridization, Transplantation, Humans, and 14 moreMale, CD, T lymphocytes, Epstein-Barr virus, Aplastic Anemia, Bone Marrow Transplantation, Adult, Immunocompromised host, Biological markers, B Lymphocytes, Viral Load, Lymphoproliferative disorders, Cardiovascular medicine and haematology, and Fatal outcome
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SUMMARY Expression of CD4 or CD8 on the cell surface is an important guide for discriminating the immunological functions of T cells. However, a minor T cell subset, which lacks both CD4 and CD8 molecules but bears the usual form of T... more
SUMMARY Expression of CD4 or CD8 on the cell surface is an important guide for discriminating the immunological functions of T cells. However, a minor T cell subset, which lacks both CD4 and CD8 molecules but bears the usual form of T cell receptor (TCR) αβ (CD4-CD8-TCRαβ+ T cells), has recently been found not only in mice but also in humans, and its role in immune response is now of considerable interest. In order to clarify the characteristics of this newly defined T cell subpopulation, we established five IL-2-dependent CD4-CD8-TCRαβ+ T cell clones from the peripheral blood of a healthy individual, and examined their various biological functions. It was found that all clones not only helped B cells in immunoglobulin production, but also exerted major histocompatibility complex-unrestricted cytotoxicity. Although their CD3/TCR complexes were functionally competent, the cytotoxicity seemed to be mediated via unknown molecules other than the CD3/TCR complex, as evidenced by the fail...
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The present study was undertaken to clarify the mechanisms of cytotoxicity mediated by virus-specific human CD4+ CTLs using the lymphocytes of family members with a Fas gene mutation. CD4+ CTL bulk lines and clones directed against... more
The present study was undertaken to clarify the mechanisms of cytotoxicity mediated by virus-specific human CD4+ CTLs using the lymphocytes of family members with a Fas gene mutation. CD4+ CTL bulk lines and clones directed against HSV-infected cells were established from lymphocytes of a patient with a homozygous Fas gene mutation and of the patient’s mother. HSV-specific CD4+ CTLs generated from lymphocytes of the patient and her mother exerted cytotoxicity against HSV-infected cells from the patient (Fas−/−) and from her mother (Fas+/−) to almost the same degree in an HLA class II-restricted manner. mRNAs for the major mediators of CTL cytotoxicity, Fas ligand, perforin, and granzyme B, were detected in these CD4+ CTLs using the RT-PCR and flow cytometry. The cytotoxicity of the HSV-specific CD4+ CTLs appeared to be Ca2+-dependent and was almost completely inhibited by concanamycin A, a potent inhibitor of the perforin-based cytotoxic pathway. Although the Fas/Fas ligand system h...
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The mechanism underlying the cytotoxicity mediated by a human CD4+ cytotoxic T-lymphocyte (CTL) clone directed against a peptide derived from the acute myelogenous leukemia-associated fusion protein, DEK-CAN, was investigated. A DEK-CAN... more
The mechanism underlying the cytotoxicity mediated by a human CD4+ cytotoxic T-lymphocyte (CTL) clone directed against a peptide derived from the acute myelogenous leukemia-associated fusion protein, DEK-CAN, was investigated. A DEK-CAN fusion peptide-specific CD4+ Th0 CTL clone, designated HO-1, was established from the peripheral blood lymphocytes of a healthy individual. HO-1 exerted direct but not “innocent bystander” cytotoxicity within 2 hours. The cytotoxicity mediated by HO-1 was completely Ca2+-dependent. Because HO-1 lysed peptide-loaded Fas-deficient target cells derived from a patient with a homozygousFas gene mutation, its cytotoxicity appeared to be mediated by a Fas-independent pathway. In addition, its cytotoxicity was only partially inhibited by treatment with concanamycin A and strontium ions, which are inhibitors of the perforin-based cytotoxic pathway. Although membrane-bound type of tumor necrosis factor- (TNF-) was expressed on HO-1, an anti–TNF- antibody ha...
Research Interests: Molecular Biology, Biology, Cytotoxicity, Apoptosis, Humans, and 15 moreBlood, Cell Death, Clinical Sciences, Apoptose, CTL, Amino Acid Sequence, Fusion Protein, Granzyme, Chromosome Translocation, Gene Expression Regulation, Macrolides, Fas Ligand, Molecular Sequence Data, Acute Disease, and Cardiovascular medicine and haematology
Adult T-cell leukemia/lymphoma is caused by infection with HTLV-1, following a long latent period. Immunotherapy targeting Aurora kinase A, a tumor-associated antigen over-expressed in adult T-cell leukemia/lymphoma, holds great... more
Adult T-cell leukemia/lymphoma is caused by infection with HTLV-1, following a long latent period. Immunotherapy targeting Aurora kinase A, a tumor-associated antigen over-expressed in adult T-cell leukemia/lymphoma, holds great therapeutic potential. We review the evidence in favor of a therapeutic strategy combining vaccination and TCR-gene transfer against this target.
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Aurora Kinase A is a cancer-associated protein normally involved in the regulation of mitosis. Being over-expressed in a range of cancers, it is a suitable target for cell-based immunotherapy. Gene transfer of T-cell receptor sequences... more
Aurora Kinase A is a cancer-associated protein normally involved in the regulation of mitosis. Being over-expressed in a range of cancers, it is a suitable target for cell-based immunotherapy. Gene transfer of T-cell receptor sequences cognisant of HLA-A*0201-restricted Aurora Kinase A antigen has previously been shown to transfer specific immunoreactivity against the target peptide in a Human Lymphocyte Antigen-restricted manner. While T cell receptor gene-transfer has great potential in overcoming the difficulties of isolating and expanding tumour-reactive lymphocytes from a patient's own cells, one hurdle is potential mispairing and competition between exogenous and endogenous T cell receptor chains. We have used a retroviral vector design bearing a short-interfering RNA that downregulates endogenous T cell receptor chains, without affecting expression of the transgenic T cell receptor sequences. The T cell receptor expression cassette also includes a 2A self-cleaving peptide...
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Mogamulizumab (Mog), a humanized anti-CC chemokine receptor 4 (CCR4) monoclonal antibody (mAb) that mediates antibody-dependent cellular cytotoxicity (ADCC) using FcγR IIIa (CD16)-expressing effector cells, has recently been approved for... more
Mogamulizumab (Mog), a humanized anti-CC chemokine receptor 4 (CCR4) monoclonal antibody (mAb) that mediates antibody-dependent cellular cytotoxicity (ADCC) using FcγR IIIa (CD16)-expressing effector cells, has recently been approved for treatment of CCR4-positive adult T-cell leukemia (ATL) in Japan. However, Mog failure has sometimes been observed in patients who have accompanying chemotherapy-associated lymphocytopenia. In this study, we examined whether adoptive transfer of artificial ADCC effector cells combined with Mog would overcome this drawback. We lentivirally gene-modified peripheral blood T cells from healthy volunteers and ATL patients expressing the affinity-increased chimeric CD16-CD3ζ receptor (cCD16ζ-T cells). Subsequently we examined the ADCC effect mediated by those cCD16ζ-T cells in the presence of Mog against ATL tumor cells both in vitro and in vivo. cCD16ζ-T cells derived from healthy donors killed in vitro Mog-opsonized ATL cell line cells (n=7) and primary ...
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The central tumoricidal activity of anticancer monoclonal antibodies (mAb) is exerted by FcγR IIIa (CD16)-expressing effector cells in vivo via antibody-dependent cell-mediated cytotoxicity (ADCC), as observed for natural killer (NK)... more
The central tumoricidal activity of anticancer monoclonal antibodies (mAb) is exerted by FcγR IIIa (CD16)-expressing effector cells in vivo via antibody-dependent cell-mediated cytotoxicity (ADCC), as observed for natural killer (NK) cells. In practice, chemotherapy-induced leukopenia and exhaustion of NK cells resulting from ADCC often hamper the clinical efficacy of cancer treatment. To circumvent this drawback, we examined in vivo the feasibility of T cells, gene-modified to express a newly generated affinity-matured (158V/V) chimeric CD16-CD3ζ receptor (cCD16ζ-T cells), as a transferable alternative effector for cancer mAb therapy. cCD16ζ-T cells were readily expandable in ex vivo culture using anti-CD2/CD3/CD28 beads and recombinant human interleukin-2 (rhIL-2), and they successfully displayed ADCC-mediated tumoricidal activity in vitro. During ADCC, ligation of opsonized cancer cells to the introduced cCD16ζ-T cells stimulated the effector cells to produce proinflammatory cyto...
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We and other groups have recently reported that CTLs that specifically recognize a peptide derived from WT1 lyse leukemia cells in a HLA class I-restricted manner. Because WT1 is expressed in various solid tumors as well as in leukemic... more
We and other groups have recently reported that CTLs that specifically recognize a peptide derived from WT1 lyse leukemia cells in a HLA class I-restricted manner. Because WT1 is expressed in various solid tumors as well as in leukemic cells, we investigated whether WT1-specific CTLs can also inhibit the growth of lung cancer by examining their cytotoxic activity against lung cancer cell lines in vitro and their inhibitory effect on the growth of human lung cancer cells engrafted into nude mice. The WT1 transcript was detected in most of the lung cancer cell lines examined. A WT1-specific, HLA-A24-restricted CTL clone (designated TAK-1) exhibited cytotoxicity against lung cancer cell lines bearing HLA-A24 but did not lyse cells lacking this HLA. This suggests that the target antigen for TAK-1 on HLA-A24-positive lung cancer cells is the naturally processed WT1 peptide. Adoptive transfer of TAK-1 into nude mice that had been engrafted with a HLA-A24-positive lung cancer cell line res...
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BackgroundImmunogenetic evidence indicates that cytotoxic T lymphocytes (CTLs) specific for the weak CTL antigen HBZ limit HTLV-1 proviral load in vivo, whereas there is no clear relationship between the proviral load and the frequency of... more
BackgroundImmunogenetic evidence indicates that cytotoxic T lymphocytes (CTLs) specific for the weak CTL antigen HBZ limit HTLV-1 proviral load in vivo, whereas there is no clear relationship between the proviral load and the frequency of CTLs specific for the immunodominant antigen Tax. In vivo, circulating HTLV-1-infected cells express HBZ mRNA in contrast, Tax expression is typically low or undetectable. To elucidate the virus-suppressing potential of CTLs targeting HBZ, we compared the ability of HBZ- and Tax-specific CTLs to lyse naturally-infected cells, by co-incubating HBZ- and Tax-specific CTL clones with primary CD4+ T cells from HLA-matched HTLV-1-infected donors. We quantified lysis of infected cells, and tested whether specific virus-induced host cell surface molecules determine the susceptibility of infected cells to CTL-mediated lysis.ResultsPrimary infected cells upregulated HLA-A*02, ICAM-1, Fas and TRAIL-R1/2 in concert with Tax expression, forming efficient target...
Research Interests: Biology, Virology, Medicine, Humans, Clinical Sciences, and 4 moreCTL, Protein Expression, Retrovirology, and Antigen
Whereas humanized mouse models have contributed significantly to human immunology research, human T cells developing in mouse thymic environment fail to demonstrate HLA-restricted function. To achieve HLA-restricted human immune response,... more
Whereas humanized mouse models have contributed significantly to human immunology research, human T cells developing in mouse thymic environment fail to demonstrate HLA-restricted function. To achieve HLA-restricted human immune response, we created an immune-compromised non-obese diabetic/SCID/IL2rg null strain (NSG) with homozygous expression of HLA class I heavy chain and light chain (NSG-HLA-A2/HHD). Transplantation of purified Lin−CD34+CD38− human hematopoietic stem cells into NSG-HLA-A2/HHD newborns resulted in the development of human CD4+ and CD8+ TCRαβ+ T cells and CD4−CD8− and CD8+ TCRγδ+ cells in recipient bone marrow and spleen. Human cytotoxic T lymphocytes (CTLs) become functionally mature, as evidenced by the production of granzyme corresponding to phenotypic transition from naïve to effector memory CTLs. In these recipients, human Th17 cells developed along with Th1 and Th2 cells. Epstein–Barr virus (EBV) infection in the humanized NSG-HLA-A2/HHD recipients resulted ...
Research Interests: Immunology, Immune response, Biology, Cell separation, Biological Sciences, and 15 moreHematopoietic Stem Cells, Cell Differentiation, Humans, Animals, Bone marrow, CD, Immune system, B Lymphocytes, Cell Proliferation, Human Disease, Hematopoietic Stem Cell, Hematopoietic Stem Cell Transplantation, Heavy Chain, Human leukocyte antigen, and B cell
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Although the cytotoxic mechanisms of murine CTLs have been investigated extensively using various mutant and knockout mice, those of human CTLs, especially CD4+ CTLs, are still obscure. To clarify the roles of perforin in Ag-specific... more
Although the cytotoxic mechanisms of murine CTLs have been investigated extensively using various mutant and knockout mice, those of human CTLs, especially CD4+ CTLs, are still obscure. To clarify the roles of perforin in Ag-specific cytotoxicity mediated by human CD4+ CTLs, alloantigen-specific and HSV-specific human CD4+ T lymphocyte bulk lines and clones were established from a patient with hereditary perforin deficiency and her healthy father, and their cytotoxic activities were investigated. Alloantigen-specific CD4+ T lymphocytes expressing perforin exerted cytotoxicity against Fas-negative as well as Fas-positive allogeneic B lymphoblastoid cell lines established from members of a family with hereditary Fas deficiency. Perforin-deficient, but not perforin-expressing, CD4+ T lymphocytes failed to show strong cytotoxicity against HSV-infected autologous B lymphoblastoid cells. Perforin-deficient CD4+ T lymphocytes could exert relatively low level cytotoxicity against allogeneic...
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Recently, HBZ has been reported to play an important role in the proliferation of adult T-cell leukaemia (ATL) cells and might be a target of novel therapy for ATL. To develop a novel immunotherapy for ATL, we verified the feasibility of... more
Recently, HBZ has been reported to play an important role in the proliferation of adult T-cell leukaemia (ATL) cells and might be a target of novel therapy for ATL. To develop a novel immunotherapy for ATL, we verified the feasibility of cellular immunotherapy targeting HBZ. We established an HBZ-specific and HLA-A*0201-restricted cytotoxic T lymphocyte (CTL) clone. Detailed study using this CTL clone clearly showed that HBZ is certainly an immunogenic protein recognizable by human CTLs; however, HBZ-specific CTLs could not lyse ATL cells. Failure of HBZ-specific CTLs to recognize human T-cell leukemia virus type 1 (HTLV-1)-infected cells might be due to a low level of HBZ protein expression in ATL cells and resistance of HTLV-1-infected cells to CTL-mediated cytotoxicity. Although HBZ plays an important role in the proliferation of HTLV-1-infected cells, it may also provide a novel mechanism that allows them to evade immune recognition.