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31.
Alloantigen presentation by B cells: two types of alloreactive T cell hybridomas, B cell-reactive and B cell-nonreactive 总被引:1,自引:0,他引:1
M Minami H Kawasaki S Taira H Nariuchi 《Journal of immunology (Baltimore, Md. : 1950)》1985,135(1):111-116
T cell-depleted, Sephadex G-10-passed unstimulated splenic B cells from C57BL/6 mice stimulated splenic T cells from CKB mice to produce IL 2 and to proliferate. The stimulatory ability of the unstimulated B cells was eliminated by 4000 rad irradiation of the unstimulated stimulator B cells. LPS-activated B cells could stimulate responder T cells more efficiently than unstimulated B cells. For further analysis of allostimulation by B cells, we established a series of alloreactive T cell hybridomas. Forty-five percent of these alloreactive T cell hybridomas could be stimulated to produce IL 2 by either macrophage-dendritic cells or unstimulated B cells. Fifty-five percent of these alloreactive T cell hybridomas could be stimulated by macrophage-dendritic cells but not by unstimulated B cells. T cell hybridomas that were not reactive with unstimulated B cells were also nonreactive to LPS-activated B cells. Analysis of two representative I-Ab-reactive T cell hybridoma clones, B cell-reactive clone CB-11.4 and B cell-nonreactive clone HTB-9.3, revealed again that the stimulatory ability of unstimulated B cells was sensitive to 4000 rad irradiation in the activation of CB-11.4 clone and that CB-11.4 could be stimulated more efficiently by LPS-activated B cells than by unstimulated B cells, but HTB-9.3 could not be stimulated by LPS-activated B cells. Thus, there may be two distinct types of T cells in the alloreaction: B-cell-reactive and B cell-nonreactive. 相似文献
32.
In order to determine whether the usual feeding pattern actually modifies the circadian rhythms of urinary excretion of water and electrolytes, we compared the circadian rhythm characteristics in patients receiving total parenteral nutrition (TPN group) with those in patients on an ordinary hospital diet (control group). Statistically significant circadian rhythms were detected in all of the urinary variables investigated herein by using the population mean-cosinor method in both groups. In addition, there were no statistically significant differences of the mesor, the %-amplitude and the acrophase between the two groups. These results suggest that the usual feeding pattern is not a main determinant in forming the circadian rhythm characteristics of human urinary variables. 相似文献
33.
Summary A 0.7 kb DNA fragment of the Escherichia coli K12 chromosome was shown to contain the structural gene for RNAse III (rnc). The DNA sequence of the gene was determined and its alteration in an RNAse III defective mutant, AB301-105, was identified. DNA sequence analysis also showed that a secondary-site suppressor of a temperature-sensitive mutation in the E. coli ribosomal protein gene, rpsL, occurred within the rnc gene, providing genetic evidence for the interaction of ribosomal proteins with RNAse III, which in turn acts on the nascent ribosomal RNA during assembly of ribosomes in E. coli. 相似文献
34.
Hiroko Nashimoto Akiko Miura Haruo Saito Hisao Uchida 《Molecular & general genetics : MGG》1985,199(3):381-387
Summary Temperature-sensitive (ts) mutations were isolated within a ribosomal protein gene (rpsL) of Escherichia coli K12. Mutations were mapped by complementation using various transducing phages and plasmids carrying the rpsL gene, having either a normal or a defective promoter for the rpsL operon. One of these mutations, ts118, resulted in a mutant S12 protein which behaved differently from the wild-type S12 on CM-cellulose column chromatography. Suppressors of these ts mutations were isolated and characterized; one was found to be a mutation of a nonribosomal protein gene which was closely linked to the RNAase III gene on the E. coli chromosome. This suppressor, which was recessive to its wild-type allele, was cloned into a transducing phage and mapped finely. A series of cold-sensitive mutations, affecting the assembly of ribosomes at 20°C, was isolated within the purL to nadB region of the E. coli chromosome and one group, named rbaA, mapped at the same locus as the suppressor mutation, showing close linkage to the RNAase III gene. 相似文献
35.
The heterogeneity of human fibroblasts as determined from the effects of hydrocortisone on cell growth and specific dexamethasone binding 总被引:1,自引:0,他引:1
To elucidate the heterogeneity of human fibroblasts from lung and skin, the effects of hydrocortisone on cell proliferation and the specific dexamethasone binding to cells were studied. Hydrocortisone at physiological concentrations stimulated the proliferation in three strains of human fetal lung fibroblasts and inhibited it in two strains. There are two kinds of fibroblasts in the human fetal lung in addition to the human skin fibroblasts reported previously. Dexamethasone-binding experiments showed that human fibroblasts may be classified into two groups with respect to the dissociation constant (Kd) of the binding reaction. The heterogeneity of human fibroblasts shown by Kd could not be correlated to classification on the basis of the effects of hydrocortisone on cell proliferation. The differences in Kd for the binding reactions suggest differences in donor tissues from which human fibroblasts are derived. 相似文献
36.
Takashi Momoi Tatsuko Furuya Yoshiyuki Suzuki Hiroko Sato Nubuo Yamaguchi 《Bioscience reports》1985,5(3):267-273
The permanent human cell lines preserving defects of lysosomal enzymes, GM1-1019-SV and SA-1077-SV, were established from the respective fibroblasts from patients with GMl-gangliosidosis and Sandhoff disease by transfection with replication origin-minus simian virus 40 DNA. These ceils grow rapidly without entering senescence during more than 120 population doublings. The activity of -galactosidase in GM1-1019-SV and of B-N-acetylhexosaminidase in SA-1077-SV was respectively 40- and 180-fold lower than that of normal fibroblasts. 相似文献
37.
A structural locus (C-6) for the sixth component of complement in mice is assigned to chromosome 15. Three-point linkage analysis indicated that the order of loci is C-6, Gpt-1, Gdc-1, and that the map distances are 25.9±4.9 between C-6 and Gpt-1, and 36.4±5.5 between C-6 and Gdc-1. Since Gdc-1 is more distal than Gpt-1, and C-6 is 26 cM away from Gpt-1, it is estimated that the C-6 is proximal to the centromere. In addition, a new C6 form found in AKR mice is described. We propose the designation C6B for it and C-6
b
for the allele encoding C6B.Abbreviations used in this paper IEF
isoelectric focusing
- GPT
glutamic-pyruvic transaminase
- GDC
L-glycerol 3-phosphate dehydrogenase
- cM
centimorgan 相似文献
38.
In vitro characteristics of rat mesangial cells in comparison with aortic smooth muscle cells and dermal fibroblasts 总被引:2,自引:0,他引:2
E Yaoita T Kazama K Kawasaki S Miyazaki T Yamamoto I Kihara 《Virchows Archiv. B, Cell pathology including molecular pathology》1985,49(4):285-294
Rat glomerular mesangial cells were cultured and their antigens were compared with those of aortic vascular smooth muscle cells and dermal fibroblasts. Glomeruli, aortic, and dermal explants were cultured for 3 weeks and subcultured in the same conditions. These cultured cells were evaluated by indirect immunofluorescence studies using antibodies against Thy-1 antigen, desmin, and chicken gizzard actin. Most of mesangial cells were positive for Thy-1, desmin, and actin. On the other hand, fibroblasts were negative for desmin, and smooth muscle cells stained Thy-1 scarcely, and were negative for desmin. In the latter two cells, actin-positive fibrils were thinner and fainter than mesangial cells. These results indicated that mesangial cells could be distinguished in vitro from vascular smooth cells and fibroblasts by immunofluorescence microscopy. 相似文献
39.
Quantitative hybridization-arrest of mRNA in Xenopus oocytes using single-stranded complementary DNA or oligonucleotide probes. 总被引:28,自引:14,他引:14
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E S Kawasaki 《Nucleic acids research》1985,13(13):4991-5004
The expression of heterologous mRNA in Xenopus oocytes was quantitatively inhibited by coinjection of single-stranded complementary DNA or synthetic complementary oligonucleotides. The lymphokines Interleukin-2 (IL-2) and Interleukin-3 (IL-3) were used as model systems to test the effectiveness of this procedure. Messenger RNA samples were hybridized to single stranded complementary DNA or oligonucleotides, injected into oocytes and the oocyte incubation medium assayed for the presence or absence of specific translation products 48 hours later. When IL-2 mRNA was hybridized to a large excess of long (490 bases) single stranded complementary DNA, the expression of IL-2 was effectively blocked (greater than 98%). Complementary oligonucleotides (18-23 bases) were almost as effective as the polynucleotide in inhibiting IL-2 activity (greater than 95%). Oligonucleotides derived from the 5' end, middle or 3' end of the coding sequence were all effective in arresting IL-2 mRNA translation. Oligonucleotide hybrid-arrest was effective even when no NaCl was present in the hybridization buffer, indicating that the annealing reaction could occur within the oocyte after injection. Definite proof that hybrid-arrest could occur in vivo was shown by the fact that oligonucleotides injected before or after mRNA injection, while not as effective as co-injection, still showed substantial inhibition of specific mRNA translation. The oligonucleotide hybrid-arrest method was equally effective in the case of IL-3, demonstrating its general applicability. 相似文献
40.
Augmentation of lung antineutrophil elastase capacity with recombinant human alpha-1-antitrypsin 总被引:6,自引:0,他引:6
Casolaro M. A.; Fells G.; Wewers M.; Pierce J. E.; Ogushi F.; Hubbard R.; Sellers S.; Forstrom J.; Lyons D.; Kawasaki G.; et al. 《Journal of applied physiology》1987,63(5):2015-2023
To evaluate the potential use of recombinant DNA-produced alpha-1-antitrypsin (alpha-1-AT) to augment the lung antineutrophil elastase defenses in alpha-1-AT deficiency, we compared the kinetics of intravenously administered recombinant produced alpha-1-AT (r alpha-1-AT) and purified normal human plasma alpha-1-AT (p alpha-1-AT) in the blood and lung of rhesus monkeys. The r alpha-1-AT was produced in yeast transformed with an expressing plasmid containing a full-length human alpha-1-AT complementary deoxyribonucleic acid and purified to greater than 99% homogeneity. The r alpha-1-AT has a molecular weight of 45,000, no carbohydrates, and is identical in sequence to normal plasma alpha-1-AT except for an additional N-terminal acetylmethionine. Despite its lack of carbohydrates, the r alpha-1-AT inhibited human neutrophil elastase with an association rate constant similar to that of p alpha-1-AT. Rhesus monkeys were infused intravenously with 120 mg/kg of r alpha-1-AT (n = 13) or p alpha-1-AT (n = 12) and the serum, urine, and lung epithelial lining fluid (ELF) concentrations of these molecules quantified at various intervals.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献