Carbohydrate antigens aberrantly expressed in colorectal carcinoma.
Explore the source record for details and available documents.
Antigens, Tumor-Associated, Carbohydrate↗
Biomedical subjects
E Sato
Publications and source records attributed to E Sato.
Expression of Fas-Fas ligand system associated with atresia in murine ovary.
We detected that Fas receptor (Fas) was expressed at transcriptional levels in oocytes/eggs and some granulosa cells of murine ovary, whereas, Fas ligand (FasL) was found to be strongly expressed in granulosa cells by means of in situ hybridisation. These results were supported by an indirect immunofluorescence (IIF) test with anti-Fas monoclonal antibody (mAb)/FasL Ab. The lysates from granulosa cells were precipitated by anti-FasL Ab, exhibiting a specific band at 40 kDa. When zona pellucida (ZP)-free eggs were incubated with granulosa cells in vitro, apoptosis (DNA fragmentation) was induced in the eggs, as detected by the terminal deoxynucleotide transferase mediated dUTP-nick end labelling (TUNEL) method. To examine whether FasL-bearing cells can induce apoptosis in eggs expressing Fas through molecular interaction between FasL and Fas, we employed a baculovirus expression system to generate FasL on the surface of Spodoptera frugiperda (Sf9) cells. The co-incubation of eggs with Autographa californica nuclear polyhedrosis virus (AcNPV) and FasL transfected Sf9 (Sf9-FasL) cells in vitro was performed and resulted in the induction of apoptosis in eggs as detected by the TUNEL method. Apoptosis was absent in eggs co-incubated with AcNPV-1393 transfected Sf9 (Sf9-1393) cells. Thus, ovarian atresia was suggested to be induced by molecular interaction between FasL on granulosa cells and Fas on oocytes/eggs during oogenesis.
Animals↗
Antigen-specific inhibition of CD4+ T-cell responses to beta-lactoglobulin by its single amino acid-substituted mutant form through T-cell receptor antagonism.
T-cell responses can be antagonized by some single amino acid-substituted analogs of a peptide ligand for T-cell receptors (TCR), and these are called TCR antagonists. In this study, we addressed the question of whether TCR antagonism can be elicited by a whole protein antigen carrying a mutated T-cell determinant region corresponding to a TCR antagonist peptide. To clarify this, we examined the ability of a single amino acid-substituted mutant form of bovine beta-lactoglobulin (beta-Lg) to inhibit three CD4+ T-cell clones recognizing a peptide corresponding to an immunodominant determinant region 119-133 of beta-Lg (p119-133). First, we identified pD129A, an analog of p119-133 with a substitution of Ala for 129Asp, as an antagonist which can inhibit the response of two of the three T-cell clones. Then, using a yeast expression system, we prepared a mutant beta-Lg (mutD129A) with the same substitution of Ala for 129Asp as that in pD129A. This mutant protein could inhibit the proliferation of the two T-cell clones in a manner similar to the effect of pD129A. From these results we can demonstrate that TCR antagonism can be elicited by peptides naturally processed from a single-substituted mutant protein as well as by the corresponding peptides added exogenously.
Alanine↗
Developmental fate of single embryonic stem cells microinjected into 8-cell-stage mouse embryos.
Embryonic stem (ES) cells are pluripotent and capable of differentiating into somatic as well as germ cell lineages when conjoined with blastomeres of early mouse embryos. However, the developmental potential of single ES cells has not been fully investigated. We injected single murine ES cells (A3-1 cell line) of 129 origin into 8-cell mouse embryos (B6xBDF1) and examined the patterns of distribution of ES-cell-derived cells in the blastocysts as well as in the fully grown chimeric mice. The ES cells underwent 1-2 cycles of mitosis between the 8-cell and the blastocyst stage when they were introduced as single cells, whereas those introduced as groups of 2-5 cells did not proliferate during the same period of development. The ES cells and their daughter cells were predominantly incorporated into the ICM. From the 63 8-cell embryos which received single ES cells microinjected into the perivitelline space, 24 newborns were obtained, and 4 (2 fertile males, 1 sterile female and 1 hermaphrodite) of them (16.6%) were chimeric. The test breeding studies revealed that all the progeny of the two chimeric males were derived from spermatozoa of 129 genotype. The relative contribution of the host-derived and the ES-cell-derived cells in different tissues of the chimeric mice was assessed by PCR analyses of the microsatellite polymorphism of genomic DNA extracted from the tissues. In two male germ line chimeras, the testes, the kidneys and the dorsal skeletal muscles exhibited exceptionally high 129 contents. Our results demonstrated that single ES cells which maintain totipotency or pluripotency of high degree are present in a colony of ES cells, and that single ES cells conjoined with the blastomeres of 8-cell-stage embryos may colonize, if the circumstances allow, almost exclusively the germ cells and concomitantly the urogenital cell lineages. Possible correlation between the allocation of the germ line and the urogenital lineages is discussed.
Animals↗
Detection of in vivo proteasome activity in a starfish oocyte using membrane-impermeant substrate.
A method was investigated for monitoring the activity of protease(s) in cytosol of a single starfish oocyte using succinyl-Phe-Leu-Arg-coumarylamido-4-methanesulfonic acid as the substrate, which was injected into the cell. After preincubation of immature oocytes with a proteasome inhibitor, N-carbobenzoxy-L-leucinyl-L-leucinyl-L-norvalinal, the initial hydrolysis of the substrate was remarkably inhibited. The inhibitor blocked 1-methyladenine-triggered cyclin degradation, which is known to be mediated by proteasome. However, calpain inhibitor E-64 did not inhibit the hydrolysis of the substrate. These results suggested that the protease activity measured by this method is mainly attributable to cytoplasmic proteasome. The hydrolysis of the substrate was partially inhibited by bestatin, suggesting that the substrate was cleaved by aminopeptidase. Thus, the initial velocity of hydrolysis of the substrate (V0) by proteasome was assayed in a living oocyte after preinjection of bestatin. The values of V0 increased gradually after 1-methyladenine addition and reached the maximum level at the time corresponding to cyclin degradation. The calculated maximum velocity of hydrolysis by a mature oocyte was approximately three times higher than that by an immature oocyte. The Michaelis-Menten constant value was also higher in mature than immature oocytes. These results suggest that proteasome-dependent proteolysis is regulated not only by ubiquitination of substrates, as is generally believed, but also by the proteasome activity itself.
Adenine↗
Expression of mucin antigens in human cancers and its relationship with malignancy potential.
Mucins are high molecular weight glycoproteins having oligosaccharides attached to the apomucin protein backbone by O-glycosidic linkages. Biochemical studies on the structures and the organ specificities of several mucin core proteins (MUC1-MUC7) have been reported during the past several years. In the present study of pancreas and intrahepatic bile duct tumors, MUC1 mucin (membrane bound mucin detected by monoclonal antibody, DF3) was highly expressed in invasive ductal carcinomas of the pancreas (IDC) and invasive cholangiocarcinomas of the liver (ICC), which show invasive growth and a poor prognosis, but it was rarely expressed in intraductal papillary mucinous tumors of the pancreas (IPMT) and bile duct cystadenocarcinomas of the liver (BDCC), which show a favorable prognosis. In contrast, MUC2 mucin (intestinal type secretory mucin detected by polyclonal antibody, anti-MRP) was rarely expressed in IDC and ICC, whereas it was highly expressed in IPMT and BDCC. The results suggest that the differences in the expression of MUC1 and MUC2 mucins are a useful prognostic indicator of malignancy potential in the neoplasms of the pancreas and intrahepatic bile duct. Moreover, the expression of MUC1 and MUC2 mucins was a useful indicator of the malignancy potential of tumors derived from other organs, such as the ampulla of Vater, stomach and breast. In another study on the expression of several MUC1 mucin antigens with different patterns of glycosylation, sialylated-MUC1 mucin detected by monoclonal antibody, MY.1E12, was found to be expressed in all the invasive carcinomas (IDC and ICC) but was not frequently seen in the non-invasive type tumors (IPMT and BDCC), although the other types of MUC1 mucins did not show such contrast between the invasive and non-invasive type tumors. The results suggest that sialylation of MUC1 mucin is associated with invasive growth of neoplasms. In contrast, our study of the expression of MUC2 mRNA (transcript of intestinal type mucin) and MUC5AC mRNA (transcript of gastric type mucin) by in situ hybridization in the tumors of the pancreas and intrahepatic bile duct found that the non-invasive type tumors (IPMT and BDCC) synthesize MUC2 mRNA and MUC5AC mRNA, whereas most of the invasive carcinomas (IDC and ICC) do not. Furthermore, patients positive for MUC2 mRNA or MUC5AC mRNA expression in the tumors showed significantly better survival than the patients with no expression. The production of MUC2 or MUC5AC, an abundant extracellular intestinal or gastric type secretory mucin with high viscosity may be correlated, by a majority of the non-invasive type tumors, with the expansive growth of the tumors that display lower levels of invasion and metastasis.
Aged↗
Epstein-Barr virus-positive multiple early gastric cancers and dysplastic lesions: a case report.
Epstein-Barr virus (EBV) has been implicated as a causal virus of gastric cancer with episomal monoclonality, elevated antibodies and a unique morphologic expression in the early intramucosal stage, but the infection mechanisms have not been demonstrated. EBV has been shown only in the cancerous lesions by the highly sensitive EBV-encoded small RNA in situ hybridization (EBER-ISH) method, not in the dysplastic mucosa adjacent to the cancer. A case is presented of multiple EBV-positive gastric cancer and dysplastic epithelium observed in a 52-year-old man. Serial cut sections of the gastrectomy specimen showed four small cancerous lesions, three of which were EBER-positive, and three EBER-positive, minute, non-cancerous dysplastic lesions. The three cancerous lesions were intramucosal cancer, with one having minimal submucosal invasion forming a lymphoepithelioma-like histology. All of these EBER-positive cancerous and dysplastic lesions showed intense CD8 T-lymphocytic infiltration. There was no such findings in the EBV-negative cancerous lesion. It was concluded that EBV infection may occur in the epithelial cells of atrophic gastric mucosa, and progress to cancer with monoclonal expansion through the EBV-positive dysplastic change. Cytotoxic T-lymphocytic reactions can occur even in the dysplastic lesions. Multifocal EBV infection in the gastric mucosa may occur and, if necessary, total gastrectomy is recommended in such a case.
Herpesviridae Infections↗
Expression of Fas ligand in murine ovary.
Corresponding to the expression of Fas in the ovarian oocytes as previously reported (Guo et al., Biochem Biophys Res Commun 1994; 203:1438-1446; Mori et al., JSIR 1995; 9:49-50), the expression of Fas ligand (FasL) in the ovarian follicle was found to be restricted in the area of granulosa cells by the indirect immunofluorescence (IIF) test. Reverse transcriptase/polymerase chain reaction (RT/PCR) technique coupled with Southern blot hybridization analysis showed that the highest level of FasL mRNA was demonstrated in murine ovaries and granulosa cells 1 day after the administration of pregnant mare's serum gonadotropin (PMSG), while the level of FasL mRNA became very weak on the day 5, respectively. The observed gradual decrease in FasL mRNA could not be attributed to a generalized degradation of cellular RNA during atresia, as evidenced by the presence of constitutive expression of elongation factor 1 alpha (EF-1 alpha) mRNA in murine ovaries and granulosa cells treated with PMSG. Furthermore, in situ hybridization analysis with a FasL-specific probe confirmed that FasL was specifically localized in the granulosa cells of most follicles and its expression was regulated by PMSG administration. FasL localized in granulosa cells might possibly play an important role in the formation of the ovarian atretic follicles, most likely depending on PMSG administration.
Animals↗
Type II pneumocytes release chemoattractant activity for monocytes constitutively.
In the present investigation, we determined whether A549 cells, a type II pneumocyte cell line, might release mediators that are responsible for monocyte chemoattractant activity (MCA) constitutively. To test this hypothesis, A549 cell supernatant fluids were harvested and evaluated for monocyte chemotaxis. A549 cell supernatant fluids showed MCA in a time-dependent manner (P < 0.001). Checkerboard analysis of 24- and 72-h supernatant fluids showed that the activity was chemokinetic rather than chemotactic. Partial characterization of 24- and 72-h supernatant fluids revealed that the mediator was composed of lipid-soluble activity that was blocked by lipoxygenase inhibitors and trypsin-sensitive activity blocked by cycloheximide. Molecular sieve column chromatography identified four molecular weight peaks. Two of four peaks were blocked by anti-monocyte chemoattractant protein-1 (MCP-1) and anti-transforming growth factor-beta (TGF-beta) polyclonal antibodies. MCP-1 and TGF-beta were detected by enzyme-linked immunosorbent assay. Leukotriene B4 (LTB4) receptor antagonist attenuated the lowest-molecular-weight peak chemotactic response, and the concentration of LTB4 was high enough for chemotactic activity. These findings suggest that type II pneumocytes may modulate the recruitment of monocytes into the alveolar space by releasing MCP-1, TGF-beta, and LTB4 constitutively.
Antibodies↗
Expression of Fas-Fas ligand system associated with atresia through apoptosis in murine ovary.
We examined the contribution of Fas and its ligand (FasL) in the process of follicular atresia using murine intraovarian follicles and pregnant mare's serum gonadotropin (PMSG)-hyperovulated eggs. Reverse transcriptase/polymerase chain reaction-Southern blot hybridization demonstrated positive expression of Fas in both intraovarian oocytes and hyperovulated eggs. In contrast, expression of FasL was only detected in granulosa cells. These findings were histologically confirmed by in situ hybridization using Fas- and FasL-specific probes. A time-course study showed that Fas mRNA was positive in atretic follicles through day 0 and day 2 of PMSG stimulation and negative thereafter. Levels of FasL mRNA were the highest on day 1 and tapered off toward day 5 of PMSG stimulation. Levels of elongation factor 1 alpha mRNA, a constitutive element, were constantly maintained throughout the experimental period. Coculture of ovulated eggs, intact and zona-free, and granulosa cells demonstrated positive TUNEL staining only in zona-free eggs. These findings indicate that follicular atresia is caused by apoptosis, and the apoptosis associated with internucleosomal DNA fragmentation is directly regulated by the Fas/FasL system.
Animals↗
Characterization of embryonic stem-like cell lines derived from embryoid bodies.
Embryoid bodies (EB) were formed by TT2 embryonic stem (ES) cells in vitro. ES-like cell lines (ESLC) were established by culturing cells obtained by disaggregation of EB at 4, 8 and 20 days after culture, and designated ESLC4, ESLC8 and ESLC20, respectively. Flow cytometric analysis indicated that the cell surface expression of Le(a) on ESLC was less than that of original TT2 ES cells, but the expression of L-CAM was comparable. After suspension culture, all of the ESLC cells formed cystic EB in vitro. In addition, some ESLC4- and ESLC8-derived EB showed signs of beating. Although coat color chimeras were able to be produced with ESCL4 at a lower rate than parental ES cells, the cells did not contribute to germ line cells in chimeras. These results suggest that the ESLC had less pluripotent than parental ES cells and also that EB formation is not useful in obtaining pluripotent cells.
Animals↗
Interleukin-13 but not interleukin-4 prolongs eosinophil survival and induces eosinophil chemotaxis.
The effects of recombinant human (rh) interleukin (IL)-4 or rhIL-13 on survival, and chemotactic activity of human eosinophils were examined. Only rhIL-13 prolonged eosinophil survival in a dose-dependent manner above 3 ng/ml. Eosinophil survival induced by rhIL-13 was inhibited by monoclonal antibodies (mAbs) against IL-3 (p < 0.01) and granulocyte-macrophage colony-stimulating factor (GM-CSF) (p < 0.05), suggesting that rhIL-13 induced IL-3 and GM-CSF production from eosinophils and an autocrine mechanism is responsible for the eosinophil survival. The effects of rhIL-13 on eosinophil chemotactic activity were also examined. rhIL-13 showed chemotactic activity for eosinophils in a dose-dependent manner. Checkerboard analysis revealed that eosinophil migration was dependent on the concentration gradient, confirming that rhIL-13 is a chemotactic factor. rhIL-4 showed no effects. IL-13 may play an important role in the survival and recruitment of eosinophils in allergic diseases.
Cell Degranulation↗
Birth of normal young by microinsemination with frozen-thawed round spermatids collected from aged azoospermic mice.
Explore the source record for details and available documents.
Aging↗
Neuropathology of HTLV-1-associated myelopathy (HAM/TSP).
In order to clarify pathogenesis of HAM/TSP, we performed a detailed neuropathologic analysis of seven autopsy patients with HAM/TSP. Inflammatory infiltrates of mononuclear cells and degeneration of myelin and axons were noted in the middle to lower thoracic spinal cords and were continuously extended to the entire spinal cord. Horizontal distribution of inflammatory lesions was symmetric at any spinal levels. Immunohistochemical analysis demonstrated T-cell dominance. The numbers of CD4+ T cells and CD8+ T cells were equally present in patients with shorter clinical course. Apoptosis of helper/inducer T cells were observed in the presence of TIA1+ cytotoxic T cells in these active inflammatory lesions. Inflammatory infiltrates were markedly decreased and CD8+/TIA1- T cells were predominated over CD4+ cells in patients with prolonged clinical course. HTLV-1 proviral DNA amounts in the freshly frozen spinal cord measured by quantitative PCR were well correlated with the numbers of infiltrated CD4+ cells. In situ PCR of HTLV-1 proviral DNA using multi-primary pairs demonstrated the presence of HTLV-1 infected cells exclusively in the mononuclear infiltrates of perivascular areas. From these findings, it is suggested that the target of the inflammatory process seen in HAM/TSP lesions may be HTLV-1 infected CD4+ T cells infiltrating the spinal cord.
Apoptosis↗
[Hyperalgesia induced by intrathecal administration of nitroglycerin involves NMDA receptor activation in the spinal cord].
Spinal NMDA receptors are involved in hyperalgesia and chronic pain. The activation of spinal NMDA receptor results in the production of nitric oxide in the second order neurons in the spinal cord dorsal horn. We investigated the effects of intrathecally administered nitroglycerin (NTG) which releases nitric oxide in the cell. Formalin test which reflects phasic and tonic nociception was used as a nociceptive measure in rats with chronically implanted intrathecal catheters. Intrathecal injection of NTG resulted in the increase of flinching behavior induced by formalin injection to one paw in phase 1 (phasic) and phase 2 (tonic) responses in a dose-dependent manner. Intrathecally administered NMDA antagonist, MK-801 (MK) dose-dependently inhibited the effect of NTG but the effect was significant only in the phase 2 of the formalin test. MK given after formalin injection had significantly less effect on the phase 2 response. L-NAME (NOS inhibitor), MB (guanylate cyclase inhibitor) and HB (nitric oxide scavenger) significantly antagonized the hyperalgesic effect of NTG in the phase 2 of the formalin test. These results show that nitric oxide plays an important role in producing hyperalgesia in the spinal cord acting postsynaptically as well as pre-synaptically.
Animals↗
[Immunohistochemical localization of MUC 1 and keratin 14 in the invasive regions of malignant eyelid tumors].
The distributional patterns of MUC 1 (the mucin whose cDNA was first cloned) and Keratin 14 (K14) in the invasive regions of malignant eyelid tumors were immunohistochemically examined by comparing with other histochemical markers. The MUC 1-positive tumor cells were detected in several serial, small, invasive tumor masses in the deep subepithelial region of the low differentiated carcinoma. They were also continuously detected in the border region between accumulated lymphocytes including T cells and tumor masses of the sebaceous carcinoma. On the other hand, K14-positive tumor cells were detected in the marginal regions of large tumor masses or those with smooth edges, some of which overlapped the distribution of MUC 1-positive cells in the tissues of undifferentiated carcinoma, squamous cell carcinoma, and sebaceous carcinoma. In general, MUC 1 may be expressed in the invasive tumor cells, whereas K14 may be expressed in the marginal cells of the stable, proliferating tumor masses.
Adenocarcinoma, Sebaceous↗
[A support system after the health examination for the aged].
Explore the source record for details and available documents.
Aged↗
Early appearance of abnormality of microperoxisomal enzymes in the cerebral cortex of senescence-accelerated mouse.
SAMP8, a substrain of senescence-accelerated mouse (SAM), has been characterized by several age-related deficits in the brain. Previously, we reported that the contents of lipid peroxides and protein carbonyl, and net generation of H2O2 were increased in the cerebral cortex of SAMP8 at 4-8 weeks of age in comparison with those in age-matched SAMR1 substrain used as a control. To study the cause of these increases, we compared the activities of antioxidative enzymes in the cerebral cortex between the two substrains. The catalase activity was decreased by 75% in SAMP8 at 4-8 weeks of age, whereas neither superoxide dismutase nor glutathione peroxidase activities were changed. The change in the catalase activity was seen only in the cerebral cortex where oxidative stress was increased in SAMP8. On the contrary, the activity of acyl-CoA oxidase, a microperoxisomal H2O2-producing enzyme, in the cerebral cortex of SAMP8 was increased 1.6 fold in comparison with that in age-matched SAMR1 without change in the activity of D-amino acid oxidase. Furthermore, the changes in the activities of catalase and acyl-CoA oxidase with age were paralleled with those observed in oxidative stress in SAMP8. These results suggest that the abnormality of activities in two microperoxisomal enzymes, catalase and acyl-CoA oxidase, may be one of the cause of the early increase in oxidative stress observed in the cerebral cortex of 4-8 weeks old SAMP8.
Acyl-CoA Oxidase↗