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1.
Dr. M. P. Pistillo N. Tanigaki O. Mazzoleni E. Ciccone U. Hämmerling M. Park P I. Terasaki G. B. Ferrara 《Immunogenetics》1987,25(3):145-151
Peripheral B lymphocytes obtained from three healthy individuals who had been immunized against peripheral blood lymphocytes from appropriate HLA-incompatible donors were transformed by the use of Epstein-Barr virus. The transformed blastoid B cells were repeatedly subcultured by means of cluster picking, and the HLA antibody-producing cultures were identified by testing the culture supernatants by means of the cytotoxicity assay, using the corresponding donor cells. Thus far, four cell lines that secrete cytotoxic HLA antibodies (MP1, 3, 4, and 5) have been established. Specific immunoabsorption experiments revealed that the antibody activity is carried by lambda-type IgM for MP1, by kappa-type IgM for MP3 and MP5, and by both for MP4. Specificity analysis of a panel of HLA-pretyped cells indicated that MP1 detects DQw2, whereas MP5 recognizes B7. The specificity of MP3 was similar to a DQ specificity termed DC5 (probably equivalent to TA10) but not the same. In the case of MP4, both of the lambda-type and kappa-type antibodies appeared to be directed toward new HLA class 11 determinants.Abbreviations used in this paper HLA
human major histocompatibility
- EBV
Epstein-Barr virus
- B-LCL
Blymphoblastoid cell line
- NA
not absorbed
- PBS
phosphate-buffered saline
- SPA
Sepharose protein A
- NRS
normal rabbit serum 相似文献
2.
DNA typing of HLA-DR
β
chain genes can discriminate between undetected alleles and real homozygotes 总被引:1,自引:0,他引:1
The polymorphism of HLA-DR antigens has been studied by Southern blot hybridization under conditions specific for the detection of the DR
chain genes. Haplotype-specific patterns were defined with DNA from DR1, 2, 3, 4, 7, w8, w11, w12, and W13 homozygous typing cells, with restriction enzymes Eco RI, Bgl I, and Pvu II. Certain serological specificities, such as DR2, DR3, and DR7, can be encoded by distinct allelic forms of DR
chain genes. The procedure of DNA typing was applied to family analysis of individuals expressing only a single DR specificity upon serological typing. Three cases are described here: (1) in family GR, phenotypic DR 7 homozygotes correspond to genomic heterozygotes, and a novel DR7 allele is described: (2) in family RU, the genes corresponding to a serologically undetected (blank) DR allele were identified by restriction fragment length polymorphism (RFLP); this novel DR haplotype has an RFLP pattern similar to those of the DRw52 family, even though this specificity was not expressed on the DR-blank lymphocytes; (3) in family RG, there is no blank allele, but a homozygote RFLP situation at the DR subregion. 相似文献
3.
Three new alloantigenic specificities of human major histocompatibility complex class 11 molecules have been defined by testing the reactivity of alloantisera at the molecular level. Two of these specificities identify different DR4 haplotypes. The Fe75 specificity is associated with the DR4/DW10 haplotype and the CBC/MRG6 specificity with the DR4/DKT2 haplotype. Both are supertypic specificities and are associated with other DR specificities as well. Both specificities are carried by class 11 molecules belonging to the first DR subset. Together with previously described determinants, these specificities contribute to serological discrimination of the different DR4 haplotypes. 相似文献
4.
C Speciale N Ferrara M A Sortino G Giammona R Bernardini D De Simone P Marano 《Bollettino della Società italiana di biologia sperimentale》1983,59(1):51-57
Evidence has been accumulated implicating sex hormones as possible modulators of extrapyramidal motor function. In the present study we have investigated the effects of estrogens, progesterone, testosterone, prolactin and calcitonin on behavioral parameters related to nigro-striatal dopaminergic system, such as haloperidol-induced catalepsy in male rats. It was found that 7-days estradiol benzoate treatment (5 micrograms/rat/day) significantly increases haloperidol-induced catalepsy, suggesting a possible antidopaminergic activity of estrogens. On the other hand, prolactin facilitates nigro-striatal dopaminergic transmission. Interestingly, 7 day treatment with medroxy-acetate progesterone (MAP, 5 mg/Kg, i.p.) brings about a trend to a decrease in haloperidol-induced catalepsy, while no significantly effect was observed following acute MAP administration at the same dose. So, it is tempting to speculate that chronic progestinic treatment may result in an increase in dopaminergic tonus. Testosterone, acutely administered (5mg/kg.s.c.) induces changes similar to those observed following progesterone administration. Finally, also calcitonin is able to influence haloperidol-induced catalepsy by markedly increasing it. 相似文献
5.
Murielle Rinaldi-Carmona Francis Barth Michel Haulme David Shire Bernard Calandra Christian Congy Serge Martinez Jeanne Maruani Gervais Nliat Daniel Caput Pascual Ferrara Philippe Soubri Jean Claude Brelire Grard Le Fur 《FEBS letters》1994,350(2-3):240-244
SR141716A is the first selective and orally active antagonist of the brain cannabinoid receptor. This compound displays nanomolar affinity for the central cannabinoid receptor but is not active on the peripheral cannabinoid receptor. In vitro, SR141716A antagonises the inhibitory effects of cannabinoid receptor agonists on both mouse vas deferens contractions and adenylyl cyclase activity in rat brain membranes. After intraperitoneal or oral administration SR141716A antagonises classical pharmacological and behavioural effects of cannabinoid receptor agonists. This compound should prove to be a powerful tool for investigating the in vivo functions of the anandamide/cannabinoid system. 相似文献
6.
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8.
The vascular endothelial growth factor (VEGF) isoforms: differential deposition into the subepithelial extracellular matrix and bioactivity of extracellular matrix-bound VEGF. 总被引:15,自引:0,他引:15 下载免费PDF全文
Vascular endothelial growth factor (VEGF)mRNA undergoes alternative splicing events that generate four different homodimeric isoforms, VEGF121, VEGF165, VEGF189, or VEGF206. VEGF121 is a nonheparin-binding acidic protein, which is freely diffusible. The longer forms, VEGF189 or VEGF206, are highly basic proteins tightly bound to extracellular heparin-containing proteoglycans. VEGF165 has intermediate properties. To determine the localization of VEGF isoforms, transfected human embryonic kidney CEN4 cells expressing VEGF165, VEGF189, or VEGF206 were stained by immunofluorescence with a specific monoclonal antibody. The staining was found in patches and streaks suggestive of extracellular matrix (ECM). VEGF165 was observed largely in Golgi apparatus-like structures. Immunogold labeling of cells expressing VEGF189 or VEGF206 revealed that the staining was localized to the subepithelial ECM. VEGF associated with the ECM was bioactive, because endothelial cells cultured on ECM derived from cells expressing VEGF189 or VEGF206 were markedly stimulated to proliferate. In addition, ECM-bound VEGF can be released into a soluble and bioactive form by heparin or plasmin. ECM-bound VEGF189 and VEGF206 have molecular masses consistent with the intact polypeptides. The ECM may represent an important source of VEGF and angiogenic potential. 相似文献
9.
Evidence for Nerve Growth Factor-Potentiating Activities of the Nonpeptidic Compound SR 57746A in PC12 Cells 总被引:2,自引:0,他引:2
Anne Pradines Marilyn Magazin Pascal Schiltz Gérard Le Fur Daniel Caput Pascual Ferrara 《Journal of neurochemistry》1995,64(5):1954-1964
Abstract: SR 57746A {1-[2-(naphth-2-yl)ethyl]-4-(3-trifluoromethylphenyl)-1,2,5,6-tetrahydropyridine hydrochloride} exhibits neurotrophic activities in vivo and in vitro. We used the rat pheochromocytoma PC12 cell line to investigate in vitro cellular changes induced by SR 57746A. A significant increase in the percentage of cells bearing neurite-like processes was obtained in cells treated by SR 57746A and nerve growth factor (NGF) compared with NGF treatment alone. SR 57746A added alone, however, had no effect on morphogenesis or on survival of cells in serum-free medium. In contrast, SR 57746A induced a "priming" effect on PC12 cells for neurite outgrowth within 6 h of addition of the protein tyrosine kinase inhibitor genistein. An increase in α-actinin content resulted from treatment with SR 57746A. Expression of NGF-mediated acetylcholinesterase and choline acetyltransferase was enhanced within 5 days by SR 57746A. The molecule also induced rapid F-actin redistribution. Within 2 min of incubation, outgrowth of F-actin-containing filopodia was clearly visible at the cell periphery, as previously shown with NGF. It is interesting that this effect of SR 57746A could be mimicked by protein tyrosine kinase inhibitors and abolished by preincubation with sodium orthovanadate, a protein tyrosine phosphatase inhibitor. 相似文献
10.
O Schettino L Ferrara P Forgione 《Bollettino della Società italiana di biologia sperimentale》1984,60(9):1751-1756
The nitrosamines have been extensively studied for their toxicity. Their formation in the foods containing nitrous and nitric derivatives is favoured by the presence of suitable substrata. In the present work have been used column and capillari GL Chromatography for the determination of some nitrosamines in altered foods. The results obtained by applying the suggested procedure to a number of altered samples have been very encouraging. 相似文献