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1.
Human tumor–infiltrating lymphocytes (TILs) derived from pleural or ascitic fluid were incubated with recombinant interleukin 2 and transfected with human tumor necrosis factor (TNF) a gene by the lipofection procedure. The resulting TILs secreted significant amounts of TNF in the culture supernatant and exhibited cytotoxicity against established cell lines, such as K562 and Daudi, and autologous tumor cells. The TNF gene–transfected TILs exhibited an augmented killing of autologous tumor cells.  相似文献   
2.
Alexia with agraphia is very rare symptom in multiple sclerosis. We present a patient of opticospinal multiple sclerosis with kanji-predominant alexia with agraphia. A 55-year-old, right-handed man was admitted to our hospital because of difficulty in reading and writing in August 2001. The patient had been diagnosed as having relapsing-remitting opticospinal multiple sclerosis eight years prior to admission. Language examination showed alexia with agraphia predominantly affecting kanji and also mild naming difficulties, but a good comprehension and a normal repetition. T2-weighted MRI demonstrated hyperintensity area in the left temporo-parietal lobe, involving the white matter beneath the postero-inferior temporal lobe and inferior parietal lobule. On brain SPECT, low blood perfusion was observed in the left temporo-parietal regions. Although agraphia for kana and alexia for both kana and kanji improved after steroid therapy, agraphia for kanji did not improve. After the treatment, high intensity area of inferior parietal lobule was disappeared on MRI, and the hypoperfusion of inferior parietal lobule on brain SPECT was also improved, but the lesion of left postero-inferior temporal lobe did not show any remarkable changes. We considered that the kanji-predominant alexia with agraphia was due to the lesions of left inferior parietal lobule and postero-inferior temporal lobe, and agraphia for kanji was due to the lesion of left postero-inferior temporal lobe.  相似文献   
3.
Using differential radiation sensitivity of components of mouse embryonal thymus, an in vitro method for studying T-cell differentiation from hemopoietic stem cells (HSCs) in the G0 phase was established. Intrathymic T-cell precursors present in embryonal thymus were found to be quite radioresistant (up to 20 Gy), and consequently 25-Gy-irradiated embryonal thymic lobes were used. Thymic lobes (25-Gy irradiated) taken from mouse fetuses (gestation day 15) were placed in Millipore-HA culture plates supported on squares of gelatin foam sponge in 24-well culture plates in which neonatal thymus stromal cells were cultured. HSCs (10(5) cells per well) in the G0 phase were added to these thymic lobes and cocultured at 37 degrees C in a 5% CO2/95% air incubator. Half the culture medium was changed every week. After 3 weeks, a large number of colonies had formed. Immunohistochemical studies and fluorescence-activated cell sorter analyses revealed that the colonizing cells regularly develop and exhibit surface markers characteristic of T cells (Thy-1, IL-2R, L3T4, Lyt-2, etc.). In situ hybridization analyses revealed that mRNA expression for T-cell receptor (TCR) beta chains occurred within colonizing cells. Using a monoclonal antibody (F23.1), expression of TCR beta-chain variable domain (V beta 8) on the surface of these developing T cells was demonstrated. These cells responded to interleukin 2 and/or anti-CD3 monoclonal antibody, indicating functional T cells. This method will be useful in studying T-cell differentiation pathways from pluripotent HSCs and in clarifying the mechanisms involved in negative and positive selection of T cells within the thymus.  相似文献   
4.
Mercury (Hg) and selenium (Se) levels were determined for erythrocytes, plasma and urine of 25 male and 29 female workers exposed to elemental mercury (Hgo) vapor. Interrelationship between the Hg levels and the Se levels was examined by the correlational analysis and the stepwise regression analysis. Indicators of Se status (erythrocyte Se levels, plasma Se levels and urinary Se levels) were closely intercorrelated; similarly, indicators of exposure to Hgo vapor (erythrocyte inorganic Hg levels, plasma Hg levels and urinary Hg levels) were significantly intercorrelated. Since plasma Hg level was one of the significant independent variables in determining the erythrocyte Se and plasma Se levels, Hgo vapor exposure was thought likely to influence the Se metabolism in workers. None of the Se status indicators were significant as determinants of the indicators of Hgo vapor exposure.  相似文献   
5.
Severe combined Immunodeficient (SCID) mice defective in stemcells for T and B cells appear to be an ideal host for constructionof chimeric mice. When bone marrow cells are used as a sourceof stem cells, however, host SCID mice do not always show sufficientreconstitutlon. In this study, fetal liver cells from AKR embryoswere transplanted into SCID mice without prior irradiation.This treatment induced full reconstltution of lymphopoiesisas evaluated by flow cytometry analysis and serum Ig production2 months after transplantation. Thus, fetal liver cells seemto be a better source for reconstitutlon of SCID mice than bonemarrow cells. Lymph node (LN) cells of these mice (FLT mice)had no proliferatlve or cytotoxlc activities against eitherhost-type (C.B-17) or donor-type (AKR) spleen cells. However,spleen cells from FLT mice exhibited marked proliferatlve andcytotoxlc activities against C.B-17 cells, with no activitiesagainst AKR cells. Spirt tolerance against C.B-17 cells In spleenand LN cells was not a transient phenomenon, since similar resultswere obtained from a cytotoxic T lymphocyte assay 4 months later.In spite of the strong host reactivity in vitro, aberrationof clonal deletion or development of a graft-versus-host diseasewas not seen in FLT mice. As IL-2 induced the host reactivityof LN cells in a mixed lymphocyte reaction, potentially host-reactiveT cells were present in LN but were rendered anerglc. Tolerancein FLT mice seems to be regulated by a peripheral mechanism.We supposed that the split tolerance in FLT mice was inducedby the different antigenicity between the spleen and LN.  相似文献   
6.
WSX-1 is a class I cytokine receptor with homology to the IL-12 receptors and is essential for resistance to Leishmania major infection. In the present study, we demonstrated that WSX-1 was also required for resistance to Trypanosoma cruzi. WSX-1-/- mice exhibited prolonged parasitemia, severe liver injury, and increased mortality over wild-type mice. WSX-1-/- splenocytes produced enhanced levels of Th2 cytokines, which were responsible for the prolonged parasitemia. Massive necroinflammatory lesions were observed in the liver of infected WSX-1-/- mice, and IFN-gamma that was overproduced in WSX-1-/- mice compared with wild-type mice was responsible for the lesions. In addition, vast amounts of various proinflammatory cytokines, including IL-6 and TNF-alpha, were produced by liver mononuclear cells in WSX-1-/- mice. Thus, during T. cruzi infection, WSX-1 suppresses liver injury by regulating production of proinflammatory cytokines, while controlling parasitemia by suppression of Th2 responses, demonstrating its novel role as an inhibitory regulator of cytokine production.  相似文献   
7.
The lysosome-associated membrane proteins (LAMPs)-1 and -2 are major constituents of the lysosomal membrane. These molecules are known to be among the most glycosylated proteins of several types of cells and cancer cells, and their expression in cancer cells is marked by a distinct difference in the structures of the oligosaccharides as compared to nonmalignant cells. We analyzed by immunohistochemistry the intensity and distribution of LAMP-1 and LAMP-2 in 9 human colorectal cancer cases and in 16 control cases, including inflammatory diseases (diverticulitis, ulcerative colitis, and Crohn's disease). LAMP proteins were expressed more intensely in the epithelium of colorectal neoplasms than in normal mucosa (P < 0.05), and no significant differences were found between adenoma and cancer cells (P > 0.05) in the same tissue section. Further, in sites of inactive inflammatory diseases and nonneoplastic areas in cancer specimens, no significant increases in epithelial LAMP proteins were observed, even in the proliferative zone of the lower crypt epithelium. Northern blot analysis showed increased expression of LAMP-1 and LAMP-2A in two of three colorectal cancers examined and increased LAMP-2B in all three cancers. Our findings suggest that LAMPs are related to neoplastic progression, but there is no direct association between the expression of LAMP molecules and cell proliferation.  相似文献   
8.
A mutant strain of rats, LEC, shows a novel arrest of T cell maturation from CD4+CD8+ to CD4+CD8- but not to CD4-CD8+ cells in the thymus. Transplantation of LEC rat fetal thymuses into the subcapsule of the kidney of athymic nude rats resulted in a normal maturation of thymocytes in the thymus graft. Furthermore, both single-positive thymocytes and peripheral lymph node T cells expressed T cell receptor alpha/beta antigen, and lymph node T cells acquired the ability to produce interleukin 2 upon mitogen stimulation. Transplantation of fetal thymuses from LEA rats, which express the same major histocompatibility complex haplotype as LEC rats, into LEC rat kidney subcapsule resulted in the maturational arrest from CD4+CD8+ to CD4+CD8- cells in the thymus graft. These data strongly suggest that bone marrow-derived progenitor T cells carry the cause of maturational arrest and that the thymic stroma of LEC rats has a normal potential to nurse thymocytes.  相似文献   
9.
K Nomoto  S Yoshida    K Himeno 《Immunology》1980,41(1):83-90
Guinea-pigs were immunized via footpads with sheep red blood cells (SRBC) in saline. Histological examination of erythematous skin reaction was performed and effects of cyclophosphamide (CY) or BCG pre-treatment on the skin reaction were examined. Delayed-in-onset erythematous skin reaction accompanied by substantial basophil infiltration was elicited in guinea-pigs immunized with SRBC in saline. The erythema was augmented in size by CY which was injected 2 days before immunization. The reaction may be comparable to Jones-Mote type. In BCG pre-treated guinea-pigs, basophil infiltration at the skin reaction sites was reduced in number, but significant inhibition of macrophage migration was not detected in the presence of SRBC antigen. The reaction may be intermediate between Jones-Mote and the tuberculin type. Comparability of delayed skin reactions in guinea-pigs and delayed footpad reactions in mice or hamsters against SRBC is discussed.  相似文献   
10.
Analyzing more than 100 independent rice cybrids, we found evidence for inter-molecular recombination between parental mitochondrial genomes occurring at high frequency soon after protoplast fusion. The structure of the region around the atp6 gene showed extensive polymorphism among Indica (MTC-5A), Japonica (Nipponbare), and wild abortive (IR58024A) mitochondrial genomes. Recombination between the mitochondrial genomes of IR58024A and MTC-5A around the atp6 gene was detected by Southern-blot analysis of cybrid plants. Such recombinant mitochondrial molecules were also cloned from IR58024A/Nipponbare cybrid callus. PCR analysis around the atp6 gene demonstrated that inter-parental recombination occurs in practically all cybrid calli within 2 weeks after protoplast fusion. At this point, parental and recombinant mitochondrial genomes coexisted within the callus. Over the course of further cultivation, however, mitochondrial genome diversity decreased as parental and/or recombinant genomes segregated out.  相似文献   
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