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991.
Jacob Lund Anne Mette Elimar Bitsch Morten Grønbech Rasch Mari Enoksson Linda Troeberg Hideaki Nagase 《MABS-AUSTIN》2018,10(1):118-128
Decysin-1 (ADAMDEC1) is an orphan ADAM-like metalloprotease with unknown biological function and a short domain structure. ADAMDEC1 mRNA has previously been demonstrated primarily in macrophages and mature dendritic cells. Here, we generated monoclonal antibodies (mAbs) against the mature ADAMDEC1 protein, as well as mAbs specific for the ADAMDEC1 pro-form, enabling further investigations of the metalloprotease. The generated mAbs bind ADAMDEC1 with varying affinity and represent at least six different epitope bins. Binding of mAbs to one epitope bin in the C-terminal disintegrin-like domain efficiently reduces the proteolytic activity of ADAMDEC1. A unique mAb, also recognizing the disintegrin-like domain, stimulates the caseinolytic activity of ADAMDEC1 while having no significant effect on the proteolysis of carboxymethylated transferrin. Using two different mAbs binding the disintegrin-like domain, we developed a robust, quantitative sandwich ELISA and demonstrate secretion of mature ADAMDEC1 protein by primary human macrophages. Surprisingly, we also found ADAMDEC1 present in human plasma with an approximate concentration of 0.5 nM. The presence of ADAMDEC1 both in human plasma and in macrophage cell culture supernatant were biochemically validated using immunoprecipitation and Western blot analysis demonstrating that ADAMDEC1 is secreted in a mature form. 相似文献
992.
The Ellis procedure of serial extraction of gonadotropins and growthhormone (GH) followed by alkaline ethanol extraction was adopted to processfreshly frozen buffalo pituitaries. The procedure after slight modificationwas found very useful as more than 2 mg of GH free immunoreactive prolactin(PRL) could be isolated from each gram of wet pituitary tissue. Further, thebiochemical purity and immunobiological potency of the extracted PRL,designated as P-I, was comparable with that of the highly purified samplesof homologous and heterologous PRLs. No non-PRL protein was detectable inP-I. Micro-heterogeneity with regard to size, charge, co- andpost-translational modifications was also investigated under differentconditions of extraction and at different stages of purification.Immunological and biological potencies were compared in homologouscompetitive enzyme linked immunosorbent assay (ELISA) developed for buffaloPRL and in rat Nb2 lymphoma proliferation assay respectively. Structuralheterogeneity was observed in all the preparations checked including freshpituitary homogenate and highly purified hormone. Nevertheless a 25 Kspecies corresponding to the hormone monomer was always the only paramountform comprising more than 90% of the total PRL protein in all thesamples including P-I. Similar size forms were observed in all preparationsand were found to be equivalents of monomers, dimers, covalent-andnon-covalent multimers, disulphide bridged forms and cleaved fragments.Other sibling species identified were glycosylated PRL, charge isoforms andforms that perhaps differed in their extractability from the pituitarytissue. Strong apparent size heterogeneity was displayed by the monomericbuffalo PRL. In light of these observations and the information on thestructural and functional significance and the consequences of polymericforms, the use of a heterogeneous PRL (P-I) as a reference hormone isrecommended for a valid assay. 相似文献
993.
尿微量白蛋白ELISA测定法最适条件的探讨 总被引:1,自引:0,他引:1
用自制兔抗人白蛋白抗体;酶标抗原和进口NUNC板, 进行了两种显色剂邻苯二胺(OPD)及四甲基联苯胺(TMB)测定尿微量白蛋白的比较,底物(H2O2)浓度对测定的影响,碳酸钠和戊二醛两种包被方法的比较,以及抗体和抗原浓度的选择等影响因素进行了实验探讨,并确定了本实验的最佳分析条件. 相似文献
994.
995.
Previous studies indicated that the high endogenous abscisic acid (ABA) content of hybrid larch ( Larix X leptoeuropaea ) somatic embryos was correlated with low germination frequency. However, when dried, the germination rate of the somatic embryos improved. Therefore, our present objective was to study the effect of desiccation on the levels of ABA and its glucose ester metabolite. Cotyledonary somatic embryos were subjected to drying treatments at 40 C under relative humidities of 98 and 59% for one week and the levels of both ABA and abscisic acid glucose ester (ABAGE) were followed by enzyme-linked immunoassay (ELISA). During desiccation at 98% relative humidity (RH) both ABA and ABAGE levels decreased in an irregular fashion. Regardless of RH, transient increases in ABA were observed that were paralleled by marked decreases in ABAGE. It is concluded that the desiccation of somatic embryos which leads to a decrease in ABA content, could explain the enhanced germination capacity of such embryos. 相似文献
996.
Michael Goetz Philippe Picard Danielle Londos-Gagliardi Bernard Guillemain Gilles Precigoux 《Letters in Peptide Science》1997,4(4-6):351-358
The envelope of the human retrovirus HTLV-I (humanT-cell leukemia virus type I), like those of otherretroviruses, plays an important role in viralinfection. One of the major immunodominant domains ofHTLV-I surface glycoprotein (gp46), inducing antibodyreactions in over 90% of infected individuals, isbounded by amino acids 175 and 199. As compared toHTLV-I prototype strain MT-2, few amino acidsubstitutions have been described in this region; themost frequently observed is the replacement of aproline by a serine at position 192. In order toinvestigate the antigenic impact of this variation, weanalysed the reactivity of synthetic peptides,harbouring either a proline or a serine residue,towards antibody containing HTLV-I positive sera inenzyme linked immunosorbent assays. The possibleinfluence of this amino acid substitution on theconformational behaviour has been examined by studyingthe solution structure of two model peptides(corresponding to the 175–199 region) usingtwo-dimensional 1H NMR spectroscopy. The resultsof this work should allow us to find out whether thisamino acid substitution has to be taken into accountfor the design of a future peptide-based vaccineagainst HTLV-I infection. 相似文献
997.
Michael Goetz Philippe Picard Danielle Londos-Gagliardi Bernard Guillemain Gilles Precigoux 《International journal of peptide research and therapeutics》1997,4(4-6):351-358
Summary The envelope of the human retrovirus HTLV-I (human T-cell leukemia virus type I), like those of other retroviruses, plays
an important role in viral infection. One of the major immunodominant domains of HTLV-I surface glycoprotein (gp46), inducing
antibody reactions in over 90% of infected individuals, is bounded by amino acids 175 and 199. As compared to HTLV-I prototype
strain MT-2, few amino acid substitutions have been described in this region; the most frequently observed is the replacement
of a proline by a serine at position 192. In order to investigate the antigenic impact of this variation, we analysed the
reactivity of synthetic peptides, harbouring either a proline or a serine residue, towards antibody containing HTLV-I positive
sera in enzyme linked immunosorbent assays. The possible influence of this amino acid substitution on the conformational behaviour
has been examined by studying the solution structure of two model peptides (corresponding to the 175–199 region) using two-dimensional1H NMR spectroscopy. The results of this work should allow us to find out whether this amino acid substitution has to be taken
into account for the design of a future peptide-based vaccine against HTLV-I infection. 相似文献
998.
Martin Mempel Bernd Günther Edgar Müller Ludwig Grüter 《Microbiology and immunology》1996,40(2):115-119
A polyclonal rabbit anti-serum against the strong slime-producing Staphylococcus epidermidis strain RP62A was absorbed with the slime-negative phase variant of this strain PV1 in order to remove not slime-specific antibodies. Using this antiserum we established an ELISA which enables detection of slime production in S. epidermidis extracts. The ELISA showed high absorbance when extracts from slime-positive strains (confirmed in the tissue culture tube test) were used as antigens. The high absorbance of slime-positive strains was greatly reduced by periodate oxidation of the extracts and was resistant to proteinase digestion suggesting that the detected antigen is composed of polysaccharides. In contrast to other rapid and simple laboratory detection methods for S. epidermidis slime, the slime-specific ELISA gave positive results in the presence of human serum. 相似文献
999.
Kei Numazaki Tadashi Ikebe Shunzo Chiba 《FEMS immunology and medical microbiology》1996,14(2-3):179-183
Abstract Chlamydia pneumoniae causes pneumonia and other respiratory infections in children, adolescents and adults. We tried to evaluate the diagnostic value of detection of serum antibodies by ELISA for C. pneumoniae infections in Japanese children. Serum IgG, IgA and IgM antibodies to C. pneumoniae were determined by the microimmunofluorescence (MIF) test. Serum IgG and IgA antibodies were also determined by ELISA test kits. Results obtained by ELISA were compared with those obtained by MIF test. IgG antibody to C. pneumoniae was detected in 135 (39.5%) by ELISA and in 125 (36.5%) by MIF out of 342 sera from Japanese infants and children without respiratory infections (aged from 2 months old to 15 years old). IgA antibody to C. pneumoniae was detected in 129 (37.7%) by ELISA and in 117 (34.2%) by MIF out of 342 sera tested. Of 342 specimens 113 were IgG-positive by ELISA and MIF (sensitivity: 90.4%, specificity: 89.9%, r = 0.853). Of 342 sera 28 had IgG antibody titers of 1:256 and none had titers 1:512 or higher by MIF. Of 28 infants and children a total of nine were less than 4 years of age. On the other hand, of 342 specimens 99 were IgA-positive by ELISA and MIF (sensitivity: 84.6%, specificity: 86.7%, r = 0.769). Of 342 sera 16 had IgA antibody titers of 1:256 or higher by MIF. Of 16 infants and children, ten were less than 4 years of age. ELISA had excellent sensitivity and specificity relative to MIF test for detection of IgC and IgA antibodies to C. pneumoniae . It was suggested that C. pneumoniae infection in Japanese infants and children under 4 years of age was not infrequent. 相似文献
1000.
The vitellogenin and vitellin concentrations in the haemolymph and ovaries of Ixodes scapularis females were determined using a double sandwich enzyme-linked immunosorbent assay. The level of vitellogenin in the haemolymph began to increase just prior to tick detachment from the host and continued to increase until 2 days after detachment. There was a slight decrease in the vitellogenin level 4 days after detachment, but a second peak was observed approximately 5 days after oviposition. Subsequent to oviposition, the vitellogenin levels in the haemolymph quickly decreased. The concentration of vitellogenin in the haemolymph ranged from 1.55 to 11.48 g l-1 during the period after dropping from the host through oviposition. The concentration of vitellin in the ovaries began to increase as the female began rapid engorgement (0.03 mg per female) and declined after oviposition (0.1 mg per female). 相似文献