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41.
Junko Shima Takayuki Yoshioka Hiroto Nakajima Hiromi Fujiwara Toshiyuki Hamaoka 《Cancer immunology, immunotherapy : CII》1988,26(1):43-47
Summary A previous paper has demonstrated that enhanced tumor-specific immunity could be induced by priming mice with Bacillus Calmette Guerin (BCG) and subsequently immunizing them with syngeneic tumor cells modified with BCG-cross-reactive muramyl dipeptide (MDP) hapten [15]. The present study establishes a tumorspecific immunotherapy protocol for a murine chronic leukemia based on the above T-T cell collaboration between antitumor effector T cells and anti-MDP hapten helper T cells induced by BCG priming. BALB/c mice which had been primed to BCG were injected intravenously (i.v.) with viable, syngeneic BCL1 leukemia cells. One week later, these mice were immunized intraperitoneally (i.p.) with unmodified or MDP hapten-modified, 10,000 R X-irradiated BCL1 cells, followed by 4 booster immunizations at 5-day intervals. The administration of unmodified BCL1 tumor cells into BCG-primed mice failed to prevent them from tumor death due to the persistent growth of preinjected BCL1 cells. In contrast, the immunization of BCG-primed, BCL1 leukemia-cell-bearing mice with MDP-modified BCL1 cells resulted in a high growth inhibition of leukemia cells and protection of these mice from death by leukemia. It was also revealed that potent tumorspecific, T-cell-mediated immunity was generated in mice which survived in this immunotherapy model. Thus, these results indicate that administration of MDP hapten-modified, syngeneic leukemia cells into leukemia-bearing mice which have been primed with BCG results in potent tumor-specific, T-cell-mediated immunity attributable to preventing the growth of disseminated leukemic cells.This work was supported by a Grant-in-Aid for the Special Project Cancer-Bioscience from the Ministry of Education, Science, and Culture, Japan
Abbreviations used: TATA, tumor-associated transplantation antigens; MDP, muramyl dipeptide; MTP, muramyl tripeptide; BCG, Bacillus Calmette Guerin 相似文献
42.
A mouse macrophage (M phi) hybridoma which produces a soluble factor responsible for the cooperation between M phi and spleen dendritic cells (DC) was constructed. The antigen-presenting activity and the stimulator cell activity in the allogeneic or syngeneic mixed leukocyte reaction of DC were significantly augmented when DC were incubated with the culture supernatant of the hybridoma treated with various stimulants including latex beads. The monokine present in the culture supernatant of the hybridoma, called dendritic cell-activating factor (DCAF), augmented the production of lymphocyte-activating factor by DC while Ia expression of DCAF-treated DC was not altered. DCAF had no effect on the antigen-presenting activity of peritoneal resident M phi or B cell blasts while the antigen-presenting activity of spleen M phi was enhanced, but the degree of the enhancement was much less than that of spleen DC. DCAF was found to have the following properties: its pI value is between pH 4 and 5; it is stable at pH 2 to 10; and it loses its activity on incubation at 75 C for 30 min. When the culture supernatant of the hybridoma stimulated with latex beads was subjected to gel filtration, the DCAF activity was detected in the 20 Kd to 25 Kd, 30 Kd to 40 Kd, and 50 Kd to 60 Kd molecular weight regions. The 30 Kd to 40 Kd fraction, which is the major peak fraction, was further purified by ion-exchange chromatography followed by gel-filtration chromatography. When each fraction was subjected to SDS-PAGE, a 30 Kd band corresponding to the DCAF activity was observed and DCAF was purified to about 90% purity. 相似文献
43.
Hiroshi Yanagawa Yoko Ogawa Kiyotsugu Kojima Masahiko Ito 《Origins of life and evolution of the biosphere》1988,18(3):179-207
We have developed experimental approaches for the construction of protocellular structures under simulated primitive earth conditions and studied their formation and characteristics. Three types of envelopes; protein envelopes, lipid envelopes, and lipid-protein envelopes are considered as candidates for protocellular structures. Simple protein envelopes and lipid envelopes are presumed to have originated at an early stage of chemical evolution, interaction mutually and then evolved into more complex envelopes composed of both lipids and proteins.Three kinds of protein envelopes were constructedin situ from amino acids under simulated primitive earth conditions such as a fresh water tide pool, a warm sea, and a submarine hydrothermal vent. One protein envelope was formed from a mixture of amino acid amides at 80 °C using multiple hydration-dehydration cycles. Marigranules, protein envelope structures, were produced from mixtures of glycine and acidic, basic and aromatic amino acids at 105 °C in a modified sea medium enriched with essential transition elements. Thermostable microspheres were also formed from a mixture of glycine, alanine, valine, and aspartic acid at 250 °C and above. The microspheres did not form at lower temperatures and consist of silicates and peptide-like polymers containing imide bonds and amino acid residues enriched in valine. Amphiphilic proteins with molecular weights of 2000 were necessary for the formation of the protein envelopes.Stable lipid envelopes were formed from different dialkyl phospholipids and fatty acids.Large, stable, lipid-protein envelopes were formed from egg lecithin and the solubilized marigranules. Polycations such as polylysine and polyhistidine, or basic proteins such as lysozyme and cytochromec also stabilized lipid-protein envelopes. 相似文献
44.
45.
Progression of the phenotype of transformed cells after growth stimulation of cells by a human papillomavirus type 16 gene function. 总被引:1,自引:1,他引:0 下载免费PDF全文
Alteration of the growth properties of the established murine fibroblast cell lines NIH 3T3 and 3Y1 was studied in monolayer cultures and in cells suspended in semisolid medium after introduction of a cloned human papillomavirus type 16 (HPV16) DNA. HPV 16 DNA stimulated both cell lines to grow beyond their saturation densities in monolayer cultures without any apparent morphological changes or tendency to pile up. These cells were also stimulated to grow in soft agar. Since essentially all the cells that received the viral gene were stimulated to grow, the growth-stimulatory activity of HPV16 appeared to be due to the direct effect of a viral gene function. The NIH 3T3 cells showed an additional change in growth properties upon prolonged incubation of dense monolayers of cells containing the HPV16 DNA; morphologically recognizable dense foci appeared at a frequency of about 10(-3). These cells, when cloned from the foci, grew more rapidly in soft agar than the parental cells and were morphologically transformed. In other words, there were two sequential steps in cell transformation induced by HPV16. Practically all the viral DNAs were present in the cells as large rearranged multimers and were integrated into host chromosomal DNA. There was no obvious difference in the state of viral DNA in the cells of the original clone or the three subclones derived from it as dense foci. There was no difference in the amount or the number of viral RNA species expressed in the cells at these two stages. The secondary changes in the growth properties of NIH 3T3 cells appear to be due to some cellular alterations. 相似文献
46.
Pigment types in sheep, goats, and llamas 总被引:1,自引:0,他引:1
D P Sponenberg S Ito K Wakamatsu L A Eng 《Pigment cell research / sponsored by the European Society for Pigment Cell Research and the International Pigment Cell Society》1988,1(6):414-418
Pigment types in various colors of fiber from sheep, goats, and llamas were assayed by a method using high performance liquid chromatography. In these three species the black/gray group is due to eumelanin, which is fully intense in all three species. Red phenotypes are due to pheomelanin and fade considerably with age in fiber from sheep and goats, but not in llamas. This phenomenon has implications on the genetic mechanisms used in generating white fiber. Brown phenotypes in sheep are due to eumelanin, in goats these phenotypes are equivocal, and they were not observed in llamas. 相似文献
47.
D P Sponenberg S Ito L A Eng K Schwink 《Pigment cell research / sponsored by the European Society for Pigment Cell Research and the International Pigment Cell Society》1988,1(6):410-413
Hair samples of various colors of horses were analyzed for content of both eumelanin and pheomelanin by a procedure using high performance liquid chromatography. The results are in accord with generally accepted genetic hypotheses accounting for the various colors. However, the results support the hypothesis that the chestnut/sorrel group of colors is conditioned by the extension locus, not the brown locus. The results also indicate that the brown locus is a likely contributor to some rare color phenotypes. 相似文献
48.
Y Kohgo Y Kanisawa S Sakamaki S Nojiri Y Ueno Y Ito Y Niitsu S Hosoi S Sato I Urushizaki 《Human cell》1988,1(1):54-59
Lymphokine activated killer (LAK) cells are generated by culture of lymphocytes with interleukin 2 (IL-2) in short term culture (3 to 5 days) and are used for adoptive immunotherapy for advanced cancer patients. The culture condition hitherto reported are essentially based on the rotating culture system, in which the maximum cell density was at 2 X 10(6) cell/ml and the cell recovery was usually less than 100%. The inability to induce LAK cells efficiently in vitro made the culturing of cells for therapy rather difficult and costly work because the mean infusion dose of LAK cells of one patient requires more than 1 X 10(10)/ml. We have therefore attempted to culture lymphocytes in 10 times higher concentration comparing with conventional methods. By using a new dialyzing culture system under continuous regulation of the amount of infused IL-2, nutrition medium, and pO2 and pCO2, we could culture cells at 2 X 10(7)/ml for more than 21 days and the resulted LAK cells showed a 100 times increase of activity on a per cell basis. By limiting dilution procedure, these killer cells mostly express T cell markers such as CD3 and CD8 but dose not express CD16. 相似文献
49.
Correlation between the virulence of Francisella tularensis in experimental mice and its acriflavine reaction was studied. The cultures derived from all four strains (Ebina, CMB2, Schu, and N9) that had long been subcultured on agar media yielded two types of colonies, i.e., acriflavine reaction-positive (acf+) and acriflavine reaction-negative (acf-) colonies. All acf+ colonies, regardless of their parent strains, were shown to be low virulent in mice. Acf- colonies were shown to be either high (Ebina, CMB2) or low (Schu, N9) virulent. The low-virulent acf- colonies gained virulence during several passages in mice, whereas the acf+ colonies remained low virulent even after the animal passages. 相似文献
50.
Immunocytochemical observation of paraquat-induced alveolitis with special reference to class II MHC antigens. 总被引:1,自引:0,他引:1
A Nakayama H Nagura T Yokoi M Ito J Asai 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(6):389-396
The expression of class II major histocompatibility complex (MHC) antigens on alveolar epithelial cells and macrophages was investigated immunocytochemically in paraquat-induced alveolitis in the rat lung. Until 2 days after paraquat injection, class II MHC antigens were expressed on the type II alveolar epithelium without any inflammatory cellular infiltration. From the 4th to the 7th day after paraquat injection, class II MHC antigen-positive macrophages increased in the alveolar spaces, whereas the expression on the type II alveolar epithelium became obscure. Over 10 days after the injection, interstitial fibrosis progressed and the intra-alveolar inflammatory infiltrates decreased. Epithelial cells lining the thickened fibrous septa no longer expressed class II MHC antigens. These results suggest that chemical stimuli can induce class II MHC antigen expression on the type II alveolar epithelium in the early stage of cellular injury, followed by inflammatory infiltration and interstitial fibrosis. 相似文献