Phase I clinical study of a peptide vaccination for hepatitis C virus-infected patients with different human leukocyte antigen-class I-A alleles.

Hepatitis C virus (HCV) infection has a high risk of liver cirrhosis and hepatocellular carcinoma at later stages. We recently identified a peptide derived from the HCV core protein capable of inducing both cellular and humoral responses to nearly all HCV-positive patients in Japan with different human leukocyte antigen (HLA)-class I-A alleles. To assess the safety and immune responses to this novel peptide, we conducted a phase I dose-escalation study of the vaccination for 26 HCV-positive patients who were either non-responders to the interferon-based therapy (n = 23) or refused it (n = 3).

Mechanisms underlying the effects of leukocyte apheresis with a fiber filter in a rat model of dextran sulfate sodium-induced colitis.

While several clinical trials have suggested that leukocytapheresis (LCAP) by filtration can benefit patients with active ulcerative colitis, the mechanisms underlying these benefits are largely unknown. The aim of this study was to address the mechanisms that may underlie the therapeutic effects of LCAP using a dextran sulfate sodium-induced colitis model in rats. Treatment with the active column, but not the sham column, improved disease severity by down-regulating pro-inflammatory events, including the cell-proliferative responses and inflammatory cytokine and reactive oxygen production, as well as by up-regulating protective events, including hepatocyte growth factor production, bone marrow-derived endothelial progenitor cell induction, and colonic blood flow levels, which were mediated predominantly by calcitonin gene-related peptide.

Pre-clinical characterization of GMP grade CCL21-gene modified dendritic cells for application in a phase I trial in non-small cell lung cancer.

Background: Our previous studies have demonstrated that transduction of human dendritic cells (DC) with adenovirus encoding secondary lymphoid chemokine, CCL21, led to secretion of biologically active CCL21 without altering DC phenotype or viability. In addition, intratumoral injections of CCL21-transduced DC into established murine lung tumors resulted in complete regression and protective anti-tumor immunity. These results have provided the rationale to generate a clinical grade adenoviral vector encoding CCL-21 for ex vivo transduction of human DC in order to assess intratumoral administration in late stage human lung cancer.

New peptide vaccine candidates for epithelial cancer patients with HLA-A3 supertype alleles.

We previously identified 2 cancer-associated antigens, immediate early response gene X-1 (IEX) and small GTPase (Ran), and their 5 epitopes using human leukocyte antigen (HLA)-A33-restricted and tumor-infiltrating T cells from a colon cancer patient. In this study, we examined whether or not these peptides can induce cytotoxic T lymphocytes (CTLs) in HLA-A11+ or HLA-A31+ epithelial cancer patients because the HLA-A11, HLA-A31, and HLA-A33 alleles share binding motifs as an HLA-A3 supertype family, which is widely distributed in many ethnic populations. Among them, the 2 peptides, IEX 47-56 and IEX 61-69, induced peptide-specific CTLs from peripheral blood mononuclear cells of cancer patients with the HLA-A11 and HLA-A31 alleles more efficiently than the other 3 peptides.

Identification of new immunogenic peptides in conserved regions of hepatitis C virus (HCV) 1b with the potentiality to generate cytotoxic T lymphocytes in HCV1b(+) HLA-A24(+) patients.

Aim: Hepatitis C virus (HCV) 1b is resistant to standard interferon therapy and has a high risk of developing into hepatocellular carcinoma at the late stage of infection. Therefore, new therapeutic modalities for HCV1b infection must be developed. One approach would be active specific immunotherapy with highly immunogenic HCV1b peptides.

Depletion of endothelial progenitor cells in the peripheral blood of patients with ulcerative colitis.

There is strong evidence to suggest that endothelial progenitor cells (EPCs) play a significant role in re-endothelialization and subsequent tissue repair. This study examined the role of EPCs in inflammatory bowel disease, a disease in which impairment of mucosal healing has been implicated. Peripheral blood mononuclear cells obtained from 50 patients with ulcerative colitis (UC), 29 patients with Crohn's disease (CD), 14 patients with infectious colitis, and 35 normal control subjects were cultured in EPC medium, harvested after 7 days, and characterized by immunocytochemistry and flow cytometry.

Identification of SART3-derived peptides having the potential to induce cancer-reactive cytotoxic T lymphocytes from prostate cancer patients with HLA-A3 supertype alleles.

SART3-derived peptides applicable to prostate cancer patients with HLA-A3 supertype alleles were identified in order to expand the possibility of an anti-cancer vaccine, because the peptide vaccine candidates receiving the most attention thus far have been the HLA-A2 and HLA-A24 alleles. Twenty-nine SART3-derived peptides that were prepared based on the binding motif to the HLA-A3 supertype alleles (HLA-A11, -A31, and -A33) were first screened for their recognizability by immunoglobulin G (IgG) of prostate cancer patients and subsequently for the potential to induce peptide-specific cytotoxic T lymphocytes (CTLs) from HLA-A3 supertype(+) prostate cancer patients. As a result, five SART3 peptides were frequently recognized by IgG, and two of them-SART3 (511-519) and SART3 (734-742)-efficiently induced peptide-specific and cancer-reactive CTLs.

Prostatic acid phosphatase as a target molecule in specific immunotherapy for patients with nonprostate adenocarcinoma.

Prostatic acid phosphatase (PAP) is one of the prostate-related antigens that are applicable to specific immunotherapy for patients with prostate cancer. In this study, we determined whether or not PAP could be a target molecule in specific immunotherapy for patients with nonprostate cancer. A variety of adenocarcinoma cell lines were examined for their PAP expression at the mRNA and protein levels by reverse transcription polymerase chain reaction and western blot analysis, respectively.

Identification of human papillomavirus 16-E6 protein-derived peptides with the potential to generate cytotoxic T-lymphocytes toward human leukocyte antigen-A24+ cervical cancer.

Human papillomavirus 16 (HPV16)-E6 and -E7 proteins are considered to be appropriate targets in specific immunotherapy for cervical cancer. In this study, we attempted to identify epitope peptides from the HPV16-E6 protein that have the potential to generate cytotoxic T-lymphocytes (CTLs) toward human leukocyte antigen (HLA)-A24+ cervical cancer. Two HPV16-E6 peptides at positions 75-83 and 91-100 effectively induced peptide-specific CTLs from peripheral blood mononuclear cells of HLA-A24+ cervical cancer patients.

Identification of peptide vaccine candidates for prostate cancer patients with HLA-A3 supertype alleles.

Purpose: The peptide vaccine candidates identified to date have been focused on the HLA-A2 and HLA-A24 alleles. The HLA-A11, HLA-A31, and HLA-A33 alleles share binding motifs and belong to an HLA-A3 supertype family. In this study, we attempted to identify CTL-directed peptide candidates, derived from prostate-related antigens and shared by HLA-A11+, HLA-A31+, and HLA-A33+ prostate cancer patients.

Determination of thrombopoietin-derived peptides recognized by both cellular and humoral immunities in healthy donors and patients with thrombocytopenia.

Thrombopoietin (TPO) is a cytokine that promotes megakaryocytopoiesis and thrombopoiesis and is considered a drug suitable for patients with thrombocytopenia. However, unexpected severe thrombocytopenia has developed in some healthy individuals participating in phase I clinical trials with a pegylated recombinant human megakaryocyte growth factor (PEG-rHuMGDF) that contained the first 163 amino acids of endogenous TPO, which resulted in hampering the further development of clinical trials. Autoimmune responses to PEG-rHuMGDF, which cross-reacted with endogenous TPO, were suggested to be involved in this rare but severe adverse event, although the immunogenic epitopes have not yet been determined.

Immunological evaluation of vaccination of peptides derived from epithelial cancer-related antigens in two patients with hematological malignancy.

Recent advances in tumor immunology have resulted in identification of many epithelial cancer-related antigens and peptides applicable to specific immunotherapy. We and others have reported that several epithelial cancer-related antigens are also expressed in hematological malignancies. Two patients with hematological malignancy (multiple myeloma and chronic lymphocytic leukemia) were vaccinated with peptides derived from epithelial cancer-related antigens to evaluate the immune responses to peptides under a personalized peptide vaccination regimen.

Ran, a small GTPase gene, encodes cytotoxic T lymphocyte (CTL) epitopes capable of inducing HLA-A33-restricted and tumor-reactive CTLs in cancer patients.

Purpose: The purpose is to identify a gene coding for tumor-associated antigen and peptide capable of inducing CTLs reactive to tumor cells with a HLA-A33-restricted fashion to provide scientific basis for specific immunotherapy to HLA-A33+ cancer patients.

Experimental Design: An expression gene-cloning method was used to identify the tumor-associated antigen gene. Northern blot analysis and immunohistochemistry were used to examine the mRNA and protein expression levels in various cells and tissues, respectively.

Expression of epithelial cancer-related antigens in hematologic malignancies applicable for peptide-based immunotherapy.

Recent advances in tumor immunology have resulted in identification of many epithelial cancer-related antigens and peptides applicable to specific immunotherapy. The authors investigated whether these peptides, which are being studied clinically, could be appropriate target molecules for treatment of patients with hematologic malignancies. The majority of hematologic malignant cells studied expressed five different epithelial cancer-related antigens.

Interleukin-5 participates in the pathogenesis of ileitis in SAMP1/Yit mice.

SAMP1/Yit mice spontaneously develop ileitis resembling Crohn's disease (CD) without chemical or genetic manipulations. Since the focus of studies were Th1 cytokines, only Th1-type T cells were thought to be responsible for intestinal inflammation in these mice. To further characterize the pathogenesis of this ileitis, we investigated the implication of Th2 cytokines in ileitis of SAMP1/Yit mice.

Immediate early response gene X-1, a stress-inducible antiapoptotic gene, encodes cytotoxic T-lymphocyte (CTL) epitopes capable of inducing human leukocyte antigen-A33-restricted and tumor-reactive CTLs in gastric cancer patients.

Peptide-based vaccine therapy, which is designed to elicit T-cell immunity against tumors, is an attractive approach for the treatment of cancer patients. To provide a scientific basis for peptide therapy, an increasing number of CTL-directed peptides have been identified, and some of them have been tried as antigen-specific immunotherapy in the past decade. Only a few studies, however, have been performed on such peptides restricted with alleles other than HLA-A2 and -A24.

Identification of peptide vaccine candidates sharing among HLA-A3+, -A11+, -A31+, and -A33+ cancer patients.

Purpose: Only a few studies have been reported on CTL epitope peptides restricted with alleles other than HLA-A2 and -A24. The HLA-A11, -A31, and -A33 alleles share similar binding motifs with HLA-A3 and -A68 alleles, and, thus, are classified as an HLA-A3 supertype. This study tried to identify CTL epitope peptides as vaccine candidates sharing by HLA-A3(+), -A11(+), -A31(+), and -A33(+) cancer patients.

Detection of a set of peptide vaccine candidates for use in HLA-A31+ epithelial cancer patients.

The molecular basis of host-tumor interaction in HLA-A31+ cancer patients has not been well understood. This lack of clarification is hampering the development of specific immunotherapies for these patients. This study aimed to identify a set of CTL-epitope peptides applicable for the specific immunotherapy of cancer patients with HLA-A31 allele.

Identification of two novel tumor-associated antigens recognized by HLA-B46-restricted cytotoxic T lymphocytes.

The objective of this study was to identify novel genes and peptides capable of inducing tumor-reactive cytotoxic T lymphocytes (CTLs) in cancer patients with an HLA-B46 allele, which is preferentially expressed in Asians. We show that two genes encoding splicing factor (SF) 2 and inosine triphosphate pyrophosphatase (ITPA) have epitopes recognized by HLA-B46-restricted and tumor cell-reactive CTL lines established from tumor-infiltrating lymphocytes of colon cancer. The SF2 is essential for constitutive pre-mRNA splicing, while the enzyme ITPA controls nucleotide levels.

Cloning of mouse Cited4, a member of the CITED family p300/CBP-binding transcriptional coactivators: induced expression in mammary epithelial cells.

The CITED family proteins bind to CBP/p300 transcriptional integrators through their conserved C-terminal acidic domain and function as coactivators. The 21-kDa mouse Cited4 protein, a novel member of the CITED family, interacted with CBP/p300 as well as isoforms of the TFAP2 transcription factor, coactivating TFAP2-dependent transcription. The cited4 gene consisted of only a single exon located on chromosome 4 at 56.

Role of the CD5 molecule on TCR gammadelta T cell-mediated immune functions: development of germinal centers and chronic intestinal inflammation.

Although CD4(+) T cells form a major subset of TCRalphabeta T cells, only a small number of TCRgammadelta T cells express CD4. Factors contributing to the down-regulation of CD4(+) TCRgammadelta T cells have not been identified. The CD5 molecule is expressed on most TCRgammadelta T cells in the spleen, whereas only a few intestinal intraepithelial TCRgammadelta T cells express this molecule in wild-type mice and TCRbeta mutant (beta(-/-)) mice.