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101.
This is the first report of nucleotide and translated amino acid sequences of the variable region light (VL) and heavy (VH) chains of mouse monoclonal hybridoma anti-blood group A and B substances, the combining sites of which have been mapped. Monoclonal hybridoma anti-A and anti-B produced in BALB/c mice by immunization with A or B blood group substances, with A1 erythrocytes, and water-soluble blood group A substance or with synthetic B determinants coupled to bovine serum albumin or to O erythrocytes have been characterized immunochemically. To relate the immunochemical properties of the monoclonals to their primary structures, we have cloned and sequenced cDNAs of variable regions of light and heavy chains of two anti-A and two anti-B. The anti-A hybridomas have very similar combining site specificities and have almost identical VH sequences belonging to the J558 germ-line family, but their VL are from different germ-line VK gene families. The two anti-B hybridomas have different combining site specificities and use the same VL which differs completely from the anti-A VL; their VH are derived from different VH germ-line genes belonging to the J606 family. The results suggest that the heavy chains play a major role in determining the specificities of the antibody combining sites, with only minor contribution of VL. Additional sequence data on monoclonal antibodies of defined specificity for blood group substances are needed for further insights into the genetic and structural basis for their specificities.  相似文献   
102.
A mouse monoclonal antibody (87.5) against Gal1-4Gal has been obtained after immunization with the disaccharide glycosidically coupled to a protein. The specificity was determined by studying its binding to a number of glycoconjugates and oligosaccharides.The antibody which was found to be highly specific for terminal Gal1-4Gal residues is a powerful tool for the detection of this structure in glycoproteins and glycolipids by immunochemicalin vitro methods. It is also useful forin vitro quantification of the free disaccharide.A thin layer chromatographic overlay assay using glycolipids and an immunoperoxidase technique is also described. The antibody 87.5 is used in this assay to identify human uroepithelium glycolipids with terminal Gal1-4Gal residues.Abbreviations Lactosylceramide Gal1-4GlcCer - globotriaosylceramide GbOse3-ceramide, Gal1-4Gal1-4GlcCer - globotetraosylceramide globoside, GbOse4-ceramide, GalNAc1-3Gal1-4Gal1-4GlcCer  相似文献   
103.
This study was conducted to assess the relative accuracy of five different assay techniques for the determination of protein concentration in human mixed saliva. The protein concentration of paraffin-stimulated saliva from 20 individuals was determined using the biuret reaction, the Lowry assay, a modified Lowry technique using bicinchoninic acid, and two dye-binding assays. Using bovine serum albumin as the standard, mean values ranged from 0.67 to 2.37 mg/ml. The use of bovine serum albumin, trypsinogen, lysozyme, bovine pancreatic ribonuclease, and poly-L-lysine as standards with the five different assay techniques to measure protein concentration of pooled mixed saliva from the above subjects produced results ranging from 0.74 to 65.5 mg/ml. The protein concentration obtained for this saliva sample by amino acid analysis was consistent with the value obtained for the biuret reaction using any of the five different standard proteins. Thus, the protein concentration obtained for human saliva depends upon both the technique used and the protein standard.  相似文献   
104.
As a result of high nutrient loading Lake Veluwe suffered from an almost permanent bloom of the blue-green algaOscillatoria agardhii Gomont. In 1979, the phosphorus loading of the lake was reduced from approx. 3 to 1 g P.m–2.a–1. Moreover, since then the lake has been flushed during winter periods with water low in phosphorus. This measure aimed primarily at interrupting the continuous algal bloom. The results of these measures show a sharp decline of total-phosphorus values from 0.40–0.60 mg P.l–1 (before 1980) to 0.10–0.20 mg P.l–1 (after 1980). Summer values for chlorophylla dropped from 200–400 mg.m–3 to 50–150 mg.m–3.The increase in transparency of the lake water was relatively small, from summer values of 15–25 cm before the implementation of the measures to 25–45 cm afterwards. The disappointing transparency values may be explained by the decreasing chlorophylla and phosphorus content of the algae per unit biovolume. Blue-green algae are gradually loosing ground. In the summer of 1985 green algae and diatoms dominated the phytoplankton for the first time since almost 20 years. To achieve the ultimate water quality objectives (transparency values of more than 100 cm in summer), the phosphorus loading has to be reduced further.  相似文献   
105.
106.
A high-performance liquid affinity chromatography column that contains immobilized anti-A monoclonal antibody specifically retards blood group A-active oligosaccharides and can be used to detect the product(s) of the reaction catalyzed by alpha-1,3-N-acetyl-D-galactosaminyltransferase: [formula: see text] After a brief incubation (15 min) of an assay mixture containing 1-100 microliters human serum, the sugar nucleotide donor UDP-GalNAc, and radiolabeled oligosaccharide acceptors 2'-fucosyllactose and/or lacto-N-fucpentaose I blood group A-active products are isolated and quantitated in a single affinity chromatographic step that takes less than 30 min. Kinetic studies to determine the pH optima for serum alpha-3-GalNAc transferase from individuals of blood groups A1 and A2 and the Km value for UDP-GalNAc for the A1 transferase agree with previous determinations. As monoclonal antibodies against many different complex carbohydrate antigens are now available, the method described could be adapted to give rapid, inexpensive assays for a variety of glycosyltransferases.  相似文献   
107.
A hemagglutinating monoclonal antibody has been obtained from a mouse/mouse hybridoma after immunisation with the leb-active oligosaccharide, lacto-N-difucohexaose I, coupled to edestin. The antibody agglutinated human red cells regardless of Lewis phenotype. Blood group O cells were strongly, agglutinated, and progressively weaker agglutination was observed with A2, B and A2B cells. Blood group A1 and A1B cells were not agglutinated.By examining the binding of the antibody to glycolipids and oligosaccharides it was shown that the Leb and Y (Ley)-haptens bind to a similar extent. Full binding activity was dependent on the presence of, both fucosyl residues.Abbreviations LND l lacto-N-difucohexaose l - IV2Fuc,lll4FucLcOse4 LND l-OL, lacto-N-difucohexaitol l  相似文献   
108.
Blood group A-active glycosphingolipids of the small intestine, A-6 and A-12, which have been characterized previously in the adult rat [Breimer ME, Hansson GC, Karlsson K-A, Leffler H (1982) J Biol Chem 257:906–12], were found to appear during postnatal development, using immunostaining on thin layer chromatograms with two monoclonal anti-A antibodies, A005 and A581. In this system, A005 was found to be specific for the A determinant based on the type 2 chain, while A581 reacted mainly with the A determinant based on the type 1 chain and only weakly with the A determinant based on the type 2 chain. A-6 Type 1 was detected first at 18 days after birth. Its concentration increased markedly during the fourth week. A-6 Type 2 was detected, at a very low level, in neonates. Its concentration increased between days 15 and 20 and then decreased almost to the neonate level by 28 days. Dodecaglycosylceramide A-12 followed the same pattern of reactivity as A-6 type 1 with A581, and remained strongly reactive with A005 after 20 days. Linear A-6 and branched A-12 appeared simultaneously. Antibodies directed against blood group H determinants based on the type 1 or type 2 chains did not detect any H structure which might have appeared as a precursor of either A-6 or A-12 at the early stages of postnatal development.Abbreviations A-6, A-12, H-5, H-10 etc the glycolipids are abbreviated by giving blood group activity, and number of sugars (see also Fig. 1) - GM3 GM3-ganglioside, H3NeuAc-LcCer - PBS phosphate-buffered saline  相似文献   
109.
110.
Summary Spleen cells from BALB/c mice immunized with cells derived from transitional cell carcinomas (TCC) of the human urinary bladder were fused with mouse myeloma Sp 2/0 Ag14 cells. Monoclonal antibodies from six established hybridomas were investigated for specificity in a cell ELISA and in indirect immunofluorescence against a large panel of fixed intact cells. Three of the antibodies reacted with half or more of the eight bladder tumors and with a few unrelated tumors. They did not react at all with malignant or normal cells of hematopoietic origin. A fourth antibody reacted with seven of eight bladder tumors. It also reacted weakly with a prostatic carcinoma, with five of six malignant or transformed B cell lines, and with a subpopulation of normal lymphocytes, but not with any of the other cells on the test panel. These four antibodies did not react with cells derived from normal urothelium. The results suggest that these antibodies might recognize cell-type-restricted antigens associated with malignancy. Another antibody reacted with almost all urothelium-derived cells. It also reacted with three of three melanomas but not with any other cells on the panel. The sixth antibody reacted with 32 of the 37 cells tested. The spectrum of reactivities displayed by the antibody suggested that it recognizes HLA antigens. Abbreviations used in this paper: TCC, transitional cell carcinoma of the urinary bladder; TAA, tumor-associated antigens; ELISA, enzyme-linked immunosorbent assay; NBCS, newborn calf serum; PBS, phosphate-buffered saline, pH 7.2; ALP, alkaline phosphatase; GDA, glutardialdehyde; BSA, bovine serum albumin; IF, indirect immunofluorescence; LCL, lymphoblastoid cell lines: B-lymphocytes transformed in vitro with Epstein-Barr virus  相似文献   
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