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At least 19 recordsLinked to original sources

A micro solid-phase radioimmunoassay for detection of herpesvirus type-specific antibody: specificity and sensitivity.

The specificity and sensitivity of a micro solid-phase radioimmunoassay (micro-SPRIA) that detects type-specific IgG antibody to herpes simplex virus types 1 and 2 (HSV1 and HSV2) were evaluated. Glycoproteins VP123 (molecular weight, 123,000) of HSV1 and VP119 (molecular weight, 119,000) of HSV2 were found to display the greatest degree of antigenic type-specificity of several HSV antigens tested with the micro-SPRIA technique. When testing a group of sera, negative for anti-HSV antibodies by microneutralization, in the micro-SPRIA, a range of negative reactivities was noted, suggesting that cut-points should be determined for each antigen preparation. The micro-SPRIA detected appropriate antibody activity in patients with recurrent infection and a marked agreement was noted in comparison to detection of anti-HSV antibodies measured with the microneutralization test. The type-specificity of the micro-SPRIA was substantiated by the independence of test results using VP119 and VP123 antigens for a random group of positive sera. The assay is rapid, specific, and sensitive and allows the testing of multiple serum samples with a standardized set of reagents.

Antibodies, Viral↗

[Immunoenzyme method of determining Pseudomonas aeruginosa exotoxin A by using a conjugate of beta-lactamase with specific antibodies].

Specific antibodies for immunoenzymatic assay of P. aeruginosa exotoxin A were isolated with affinity chromatography on exotoxin A-Sepharose 4B. A conjugate of the antibodies to exotoxin A with beta-lactamase from Bacillus licheniformis 749/c was prepared by linking glutaric aldehydes. The conjugate showed high immunospecific and enzymatic activity and was used for competitive solid phase immunoenzymatic assay. Sensitivity of the assay provided determination of exotoxin A in concentration of 20 ng/ml. It was used for determining P. aeruginosa exotoxin A in culture fluids.

ADP Ribose Transferases↗

Availability of hyperacetylated H4 histone in intact nucleosomes to specific antibodies.

Specific antibodies against the tetra-acetylated form of H4 histone have been elicited in the rabbit. They do not cross-react with the non-, mono-, and di-acetylated forms of the histone molecule but a slight cross-reactivity with the tri-acetylated form of H4 histone is observed. Our studies also show that hyperacetylated H4 histones are recognized by the antibodies in intact nucleosomes.

Acetylation↗

Analysis of yeast RNA polymerases with subunit-specific antibodies.

Specific antibodies directed against each polypeptide component of yeast RNA polymerases A or B were prepared and their affinity spectrum determined by protein blot immunodetection. The majority of enzyme A or B subunits were specifically recognized by their respective antiserum. A direct correspondence was established between the polypeptides immunologically related in the three forms of RNA polymerases A, B, and C by reacting the different antibodies with enzymes subunits transferred to a nitrocellulose membrane. Subunit-specific antibodies and antibodies to native enzymes A and B were used to probe the activity of RNA polymerases A, B, and C. Based on DNA protection experiments, the largest subunit of enzymes A and B as well as the common subunit ABC23 appear to be involved in DNA binding.

Antibodies↗

Mechanism of decreasing liver uptake of 111In-labeled anti-carcinoembryonic antigen monoclonal antibody by specific antibody pretreatment in tumor bearing mice.

The purpose of this study was to examine the mechanism of specific antibody pretreatment for reduction of liver uptake of 111In-labeled monoclonal antibody (MAB). Previous work with an anti-carcinoembryonic antigen (CEA) MAB (T84.66) and LS174T human colon cancer xenografts in nude mice has shown that giving a high dose (0.2 mg) of unlabeled T84.66 in conjunction with the same MAB (T84.66) labeled with 111In (Indacea) significantly lowered the liver uptake of 111In. High performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis were used to assess the radiolabeled components in serum and liver at different times following administration of Indacea in normal and tumor bearing mice. In serum the 111In remained associated with the IgG in both tumor bearing and non-tumor bearing mice. Liver uptake of 111In in mice without tumor was low (8-12% injected dose/g) and both IgG and a low molecular weight metabolite were found in the liver homogenates. Liver uptake in tumor bearing mice increased dramatically (15-40% injected dose/g) with size of tumor and in addition to the IgG and low molecular weight components, a high molecular weight compound was identified. Administration of CEA: Indacea complexes to non-tumor bearing mice produced the same high pressure liquid chromatography and gel patterns as those seen in mice with large (greater than 1 g) tumors. Liver homogenates from tumor bearing mice given specific antibody pretreatment showed the same patterns seen with non-tumor bearing mice (no high molecular weight peak). In conclusion, CEA:Indacea complexes are formed in tumor bearing mice and rapidly cleared by the liver. Specific antibody pretreatment results in the production of unlabeled CEA:MAB complexes causing a reduction in the formation of CEA:Indacea complexes and a lower liver uptake of 111In.

Animals↗

Expression patterns of DNA replication enzymes and the regulatory factor DREF during Drosophila development analyzed with specific antibodies.

Specific antibodies were prepared against Drosophila DNA polymerase epsilon and DREF, a regulatory factor for DNA replication-related genes. Using these antibodies together with those for DNA polymerase alpha and proliferating cell nuclear antigen (PCNA), we examined expression patterns and sub-cellular distributions of these proteins during Drosophila development. DNA polymerase alpha, epsilon and PCNA proteins were maternally stored in unfertilized eggs and maintained at high levels during embryogenesis. With distinct nuclear localization, proteins were observed in embryos at interphase stages throughout the 13 nuclear division cycles, suggesting that they all participate in rapid nuclear DNA replication during these cycles. In contrast, maternal storage of a DREF protein was relatively low and its level increased throughout embryogenesis. Strong nuclear staining with the anti-DREF antibody was not observed until the nuclear division cycle 8. Immunostaining of various larval tissues from transgenic flies carrying the PCNA gene promoter-lacZ fusion gene revealed co-expression of DREF, PCNA and lacZ, suggesting that DREF regulates the expression of PCNA gene in these tissues. In addition, we detected a relatively high level of DREF in adult males as well as females. Since DNA polymerase alpha, epsilon and PCNA are hardly detectable in adult males, DREF very likely regulates genes other than those closely linked to DNA replication in adult males.

Animals↗

[Localization of mitochondrial cytochrome b using specific antibodies].

Specific antibody has been obtained against cytochrome b (pig heart mitochondria). It inhibits the electron transport of the respiratory chain in the intact mitochondria at the cytochrome b site of the inner mitochondrial membrane. It has no effect on the isolated submitochondrial particles which are inside-out inner membrane vescicles free of any outer membrane or outside-out inner membrane. These findings indicate a probably not transmembranous topologic localization of cytochrome b; this component of the respiratory chain seems located near the outer side of the inner mitochondrial membrane.

Animals↗

Inhibition of horseradish peroxidase activity by specific antibody: determinant specificity of anticatalytic antibodies.

Rabbit antisera specific for horseradish peroxidase inhibit the catalytic activity of the enzyme. All antibodies prepared against the holoenzyme react with the peroxidase apoenzyme. However, only a minority (30-45%) of the total antiperoxidase pool cross react with reduced and alkylated apoenzymes. The antibodies inhibiting peroxidase activity do not bind to S-carboxymethyl of S-carboxamidomethylated apoenzyme derivatives as measured by absorption and competition of inhibition experiments. Glycopeptides derived from horseradish peroxidase also failed to bind anticatalytic antibodies. Antibodies that inhibit enzyme activity have specificity for noncarbohydrate conformation dependent antigenic determinants of horseradish peroxidase. Additional experiments probed the mechanism by which inhibitory antibody decreases the catalytic activity of horseradish peroxidase. Absorption spectra of horseradish peroxidase that has bound Fab fragments sufficient to cause 90% inhibition of the enzyme activity determined that the enzyme retained the ability to bind hydrogen peroxide. Thus, anticatalytic antibodies do not prevent the formation of the first enzyme-substrate intermediate but mediate their inhibitory effects by disrupting a later step in the reaction mechanism.

Antibody Specificity↗

Effect of pili-specific antibodies on the adherence of Haemophilus influenzae type b to human buccal cells.

Different strains of Haemophilus influenzae type b (Hib) produce antigenically distinct pili that mediate adherence to human buccal epithelial cells. This study determined the ability of antibodies specific for the LKP3 pili of Haemophilus influenzae type b to inhibit the adherence of Hib strain Eagan (p+). Antiserum was prepared by immunization of rabbits with pili purified from Hib strain Eagan (p+). The presence of pili-specific antibodies in the immune serum was shown by selective immunoprecipitation of pilin and by electron microscopy of cells labeled with immunogold. Immune serum, affinity-purified antibody, and Fab fragments from immune serum significantly inhibited (P less than .001) adherence of strain Eagan (p+) to human buccal epithelial cells whereas preincubation with preimmune rabbit serum or Fab fragments from preimmune serum had no significant effect on adherence. Dilution of the immune serum, affinity-purified antibodies, or Fab fragments from immune serum resulted in decreased inhibition of Hib adherence. These results indicate that antibodies specific for LKP3 pili can effectively inhibit adherence of Hib strain Eagan (p+) and probably other strains that express this pilus serotype.

Agglutination Tests↗

Serum analysis after transplant nephrectomy reveals restricted antibody specificity patterns against structurally defined HLA class I mismatches.

This study deals with HLA-mismatched kidney transplants that have been removed following rejection. Sera from 27 patients were screened for HLA-specific antibodies by direct complement-dependent lymphocytotoxicity with HLA-typed cell panels. Circulating donor-specific antibodies were detected in 3 cases (11%) before and in 26 cases (97%) after allograft nephrectomy. These findings demonstrate the production of donor-specific antibodies in patients with rejected transplants, but in most cases, they were undetectable before nephrectomy, because the graft had adsorbed them. With an HLAMatchmaker-based serum analysis program, we observed restricted antibody specificity patterns against amino acid triplet-defined epitopes on donor HLA-A,B antigens. Many donor triplets were non-reactive while others were apparently recognized by antibodies. In some patients, the donor triplet specific antibodies persisted for a long time whereas in many other patients, they became undetectable after a few months. The characterization of the antibody specificity profiles of post-allograft nephrectomy sera is clinically useful in defining criteria of HLA mismatch acceptability for sensitized patients awaiting another transplant. It provides also opportunities for determining the relative immunogenicity of mismatched triplets.

Adult↗

Induction of auto-anti-idiotypic antibodies specific for antibodies to matrix and envelope glycoprotein from pigs experimentally infected with porcine reproductive and respiratory syndrome virus.

Auto-anti-idiotypic antibodies (Aab-2s) specific for antibodies against envelope glycoprotein GP5 were previously identified in 10 of 12 pigs experimentally infected with porcine reproductive and respiratory syndrome virus (PRRSV). In this study, we report in addition the induction of Aab-2s specific for antibodies against matrix (M) and envelope glycoprotein GP5 antigens in 38 of 47 pigs experimentally infected with PRRSV. Two sets of Aab-2s were induced in the sera, one at 21 days post-infection (DPI) and peaked on 35 DPI and another at 49 DPI and peaked on 77 DPI. The Aab-2s induced at an early stage were from non-virus carrier pigs as defined when they were euthanized on and after 77 DPI. In contrast, the Aab-2s induced at a later stage were from virus carrier pigs. These Aab-2s possessed the characteristics of internal image Ab-2s and recognized shared idiotypes on swine and murine antibodies to the GP5 and M antigens of PRRSV. This study further demonstrates that, during the antibody responses to PRRSV infection, Aab-2s specific for both anti-M and anti-GP5 antibodies were induced. More importantly, the early and late Aab-2s possessed different idiotype-binding specificities. By detecting and characterizing these Aab-2s, it may be possible to identify whether pigs infected with PRRSV will clear the virus or become virus carriers.

Animals↗

Natural infection of man with group A streptococci. Levels; restriction in class, subclass, and type; and clonal appearance of polysaccharide-group-specific antibodies.

The level of antibodies specific for the two serologically distinct polysaccharides of group A and group A-variant streptococci was investigated in human sera by a modified Farr technique. Whereas there was an obvious relationship between the anti-streptolysin O titer and the level of group-A-specific antibodies, suggesting a recent streptococcal infection with group A streptococci, this correlation was not apparent for the level of group A-variant antibodies. There is evidence suggesting that children have significantly lower group A polysaccharide antibody levels than adults; this is not true of their group A-variant antibody levels. There was an apparent restriction of groups A- and A-variant-specific antibodies to the kappa light-chain type and IgG2 heavy-chain subclass. Whereas only one serum contained group A-specific antibodies also associated with IgG3 heavy chains, nine sera contained anti-group A-variant-specific antibodies with both IgG2 and IgG3 heavy chains. No anti-polysaccharide activity was detected in the IgM and IgA class of serum antibodies. Anti-group A and anti-group A-variant antibodies of human sera are restricted with respect to the number of clonotypes that are shown by isoelectric focusing. The most heterogeneous sera contained roughly ten clonotypes.

Antibodies, Bacterial↗

Acanthocheilonema viteae (Dipetalonema viteae) in mice: differences in the relative binding of microfilarial surface-specific antibody may explain the contrasting response phenotypes of BALB/c and C57BL/10.

Experiments were carried out to obtain additional data concerning the role of IgM antibodies, specific for the cuticular surface of the microfilariae (mf) of A. viteae, in clearing microfilaraemia from high- and low-responder mice infected by transplanted adult worms. Although BALB/c mice, which sustain a chronic microfilaraemia, produced IgM mf surface-specific antibodies, the binding to target mf was weak when compared to that of antibodies from the serum of the resistant C57BL/10 mice. Furthermore, antibodies from BALB/c mice were not as efficient as those from C57BL/10 mice in promoting the adherence of immune or control leukocytes to mf in vitro. Evidence is provided to show that mf shed surface bound antibody. Although the results do not establish conclusively the mechanism underlying the contrasting response phenotypes of C57BL/10 and BALB/c mice, they provide support for the involvement of antibody in controlling microfilaraemia and suggest that quantitative and qualitative differences in the amount and affinity of IgM antibody specific for the mf surface, together with the natural tendency of the mf to shed surface bound antibody at 37 degrees C, may combine to allow the former strain to clear microfilaraemia efficiently whilst the latter sustains a chronic infection.

Animals↗

Immune capacity of the chicken bursectomized at 60 H of incubation. Effect of bursal epithelial cells and bursal epithelium-conditioned medium on the production of immunoglobulins and specific antibodies in vitro.

Cells from chickens bursectomized at 60 h of incubation (Bx) are known to produce immunoglobulins without any detectable antibody specificity. In the present work cells from Bx birds were cultured together with bursal epithelial cells (BE) or bursal epithelium-conditioned medium (BECM) to establish whether they could be induced to produce specific antibodies. Cells obtained from 10-day-old or 10-week-old birds were used. The effects were assessed with regard to the production of total immunoglobulins and specific antibodies; the birds had been preimmunized. BE had no effect on the production of immunoglobulins by either Bx or control (Co) cells. When cells from 10-week-old birds were cultured in the presence of BECM, no difference in the immunoglobulin production was seen between Bx and Co chicken cells. At the age of 10 days the cells of Bx birds produced considerably less Ig than the cells of normal Co birds. At this age BECM had no effect on the Co cells, but it markedly enhanced the production of IgA-class immunoglobulins of Bx birds. With regard to production of specific anti-tetanus antibodies, BE stimulated the production of IgA-class antibodies by cells from preimmunized Co chickens but had no effect on cells from preimmunized Bx birds. In spite of the normal production of immunoglobulins in vitro the cells of Bx chickens did not produce specific antibodies. In conclusion, these findings indicate that if B cells have matured without a contact with the bursa of Fabricius, later in vitro exposure to BE or BECM can no longer induce them to production of specific antibodies.

Aging↗

The effects of virus-specific antibodies on the replication of bovine respiratory syncytial virus in vitro and on clinical disease and immune responses in lambs.

Low concentrations of antibodies, specific to human respiratory syncytial virus (RSV) have been shown to enhance virus replication in human monocytic cell lines by several workers. In the present study, replication of bovine RSV in ovine peripheral blood monocytes was shown to be enhanced in the presence of low concentration of bovine RSV-specific antibodies. Antibodies had no enhancing effect on virus replication in secondary lamb testis cells or monocytic cell lines derived from peripheral blood monocytes. The possible effects of low titres of bovine RSV-specific antibodies on the development of clinical disease were examined by inoculating groups of lambs with a mixture of virus and antibodies and assessing the severity of clinical disease and by measuring venous oxygen (PO2) and carbon dioxide (PCO2) tensions, as hypoxia has been associated with respiratory diseases. Inoculation of bovine RSV and virus-specific antibody complexes to lambs did not enhance clinical disease and had no effect on the clinical chemistry, haematology and PO2 and PCO2 tensions. Groups of lambs inoculated with virus alone or virus-antibody complexes developed significant humoral and cellular immune responses. There was no significant difference in the cellular immune responses of lambs exposed to virus alone and lambs exposed to virus-antibody mixture, as measured by virus-specific lymphocyte transformation or by cytotoxicity assays but the period of virus shedding was longer in lambs inoculated with a mixture of virus and immune serum.

Animals↗

Specific antibody to Haemophilus somnus in the bovine uterus following intramuscular immunization.

Sources of anti-Haemophilus somnus antibody in bovine uterine secretions following intramuscular immunization and subsequent intrauterine inoculation of killed H. somnus were investigated. Holstein cattle (n = 21) were immunized with a 270-kDa outer membrane protein from H. somnus (omp-270) by intramuscular injection. At estrus, the cattle were given an intrauterine inoculum of a heat-killed suspension of a homologous strain of H. somnus containing omp-270 (n = 7), a heterologous strain of H. somnus lacking omp-270 (n = 7), or phosphate-buffered saline (n = 7). Uterine secretions were sampled by saline lavage immediately prior to inoculation and at 6, 24, 48, 72, 96, and 120 h after inoculation. Immunoglobulin G subclass I (IgG1) and IgG2 antibody specific for omp-270 were detectable in estrous uterine secretions of all systemically immunized cattle from which an adequate sample was obtained. IgM antibody specific for omp-270 was detected in serum following immunization but was not consistently detected in the uterine secretions of any animal. IgA antibody specific for omp-270 was not detectable in either serum or uterine secretions following immunization or intrauterine inoculation. Ratios of antibody to immunoglobulin and ratios of immunoglobulin to albumin in serum and uterine secretions indicated that about half the IgG1 and essentially all the IgG2 in secretions originated in the serum. Relative titers of IgG1 and IgG2 omp-270-specific antibodies in the uterine lumen and serum gave no evidence for selective transport of either subclass from serum into local secretions. Neither heterologous nor homologous intrauterine inocula detectably altered the serum contribution to antibody in uterine secretions within the sampling period. On the basis of these results, development of a systemic IgG2 antibody response may provide the basis for local immunological protection in the bovine reproductive tract.

Animals↗

Seroepidemiology and control of genital herpes: the value of type specific antibodies to herpes simplex virus.

Herpes simplex virus (HSV) type 2 is the main cause of genital herpes infections. Conventional serological techniques cannot discriminate between antibodies specific to HSV types 1 and 2, so these methods cannot be used in the seroepidemiological investigation of genital herpes infections. The discovery of type specific antigens in HSV-1 and HSV-2, most notably glycoprotein G (gG), has been successfully exploited to develop assays for the detection of type specific HSV antibody. The presence of type specific antibodies provides evidence for infection with HSV-1, HSV-2, or both. Tests which detect humoral responses to HSV-2 have been used during the past decade to investigate populations in various countries. Most surveys of general adult populations in the developed world have found a relatively low seroprevalence of HSV-2, although this does differ between countries. Studies of HSV-2 antibody in developing countries have revealed higher rates of infection in adults. People attending sexually transmitted diseases (STD) clinics have higher rates of HSV-2 infection than general populations sampled in the same country. Assays of HSV type specific antibodies have been used in seroepidemiological surveys that include information about demography and sexual behaviour to identify risk factors for HSV-2 infection. The surveys show that people with a large number of sexual partners are at increased risk of acquiring HSV-2 infection and that a high proportion of HSV-2 infections are asymptomatic. Assays of HSV type specific antibody have been used to show that the presence of pre-existing HSV-1 antibody may reduce the severity of genital HSV-2 infection. Such assays have also been used in studies of the transmission of genital herpes. Proposed interventions to counter the spread of genital herpes include targeted education and vaccination programmes. Assays of HSV type specific antibodies may be used to monitor the effectiveness of such policies.

Adult↗

Nucleotide cofactor-binding-domain-specific antibodies show immunologic relatedness among unrelated proteins that bind phosphoryl compounds.

The immunologic relatedness of various cofactor-binding sites of enzymes requiring different nucleotide cofactors was examined. Chicken antibodies specific for NADPH- or CoA-binding domains were raised using an NADPH- or CoA-requiring enzyme as an immunogen. Antibodies specific for either NADPH- or CoA-binding domains were isolated by immunoaffinity chromatography of the respective antisera using unrelated NADPH- or CoA-requiring enzymes as affinity ligands. The reactivities of the NADPH- and CoA-binding-site-specific antibodies with a variety of enzymes that required different cofactors was shown on Western blots of SDS-PAGE of the enzymes. Variable cross-reactivities were observed among all nucleotide-cofactor requiring enzymes with each specific cofactor-domain-antibody population. Numerous proteins not physiologically associated with nucleotide cofactors, including acyl carrier protein, were completely unreactive. Proteins that bound phosphoryl compounds either as substrates or cofactors showed varying degrees of reactivity with each population of specific antibodies. These included aldolase, ribulose-1,5-bisphosphate carboxylase/oxygenase, ribonuclease A, carbonic anhydrase and triosephosphate isomerase. The immunologic cross-reactivity suggested that these proteins share a common structural feature, probably a primary structure epitope, since the proteins had been subjected to denaturing polyacrylamide gel electrophoresis. A candidate for this common structural feature is a glycine-rich sequence comprising a phosphate binding loop.

Animals↗