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At least 19 recordsLinked to original sources

Creatine kinase isoenzyme--antibody reactions in immuno-inhibition and immunonephelometry.

I have raised, in rabbits, antibodies against MM and BB isoenzymes of creatine kinase. The antibodies produced were homogeneous by Ouchterlony double immunodiffusion and did not cross react with their opposite antigens. Both antisera, however, appeared to be mixtures of antibodies, displaying different equivalences for activation, inactivation, and, possibly, precipitation. Inactivation studies indicated the presence of antibodies effective against dimer only and antibodies effective against monomer or dimer. Both antisera cross reacted with MB and displayed antibodies that appeared to block only half of the activity as well as antibodies that blocked all of the activity. The antisera produced were useful for measuring MB by both immuno-inhibition and immunonephelometry, but neither appears to be advantageous over current electrophoresis or ion-exchange methods. A comparison of decay of MB in patients between activity and mass measurements indicated that activity decay is about 12-fold faster than mass decay.

Animals

Synthesis of high affinity antibodies in irradiated rabbits grafted with allogeneic cells from hyperimmune donors.

Irradiated rabbits grafted with allogeneic lymph node, spleen and bone marrow cells from a donor rabbit hyperimmunized against TMV synthesize high affinity antibodies, displaying mainly recipient allotypic specificities, after antigen boosting. By contrast, recipient rabbits from non-immune donors synthesize antibodies of lower affinity. It is suggested that the differentiation of new emerging host B cells is specifically influenced by the presence of donor-memory cells.

Absorption

Evolution of antibody cross-reactivity to influenza H5N1 neuraminidase from an N2-specific germline.

The ongoing spread of highly pathogenic avian influenza H5N1 clade 2.3.4.4b virus in animals and its occasional spillover to humans have raised concerns about a potential H5N1 pandemic. Although recent studies have shown that pre-existing human antibodies can recognize H5N1 neuraminidase, the molecular basis of how this cross-reactivity develops remains poorly understood. In this study, we used a phage display antibody library derived from 245 healthy donors to isolate an antibody, HB420, that cross-reacts with neuraminidases of human H3N2 and avian H5N1 clade 2.3.4.4b viruses and confers protection in vivo. Cryogenic electron microscopy analysis reveals that HB420 targets the neuraminidase active site by mimicking sialic acid binding through a single Asp residue. Furthermore, the inferred germline of HB420 is N2 specific but acquires cross-reactivity to H5N1 neuraminidase through somatic hypermutation. Overall, our findings provide insights into how neuraminidase antibody evolves breadth, which has important implications for the development of broadly protective influenza vaccines.

Influenza A Virus, H5N1 Subtype

[Ability of FAB-fragments of normal rabbit and human gamma globulins to suppress human lymphocyte blast transformation induced by phytomitogens].

Monovalent and bivalent Fab-fragments of normal human or rabbit gamma-globulin suppressed blasttransformation of human lymphocytes induced by phytohemagglutinin and concanavalin A. Peptic F(ab)2-fragments from highly-purified rabbit anti-DNP antibody displayed suppressing activity similar to that of the fragments of normal gamma-globulin. Fab-fragments affected blasttransformation when added to lymphocytes either simultaneously with the PHA or 24 and 48h after the mitogen. The data obtained may indicate that the inhibiting of lymphocyte blasttransformation produced by the gamma-globulin fragments was not caused by their competing with mitogens for the receptors on the target-cell; the Fab-fragment activity was probably determined by the structures located outside the antibody active centre.

Animals

The immunochemistry of antibodies sharing concanavalin A's anti-mannosyl binding specificity.

Procedures were developed for the synthesis of the disaccharide hapten, p-isothiocyanatophenyl 2-O-alpha-D-mannopyranosyl-alpha-D-mannopyranoside, and for its conjugation to hemocyanin. The synthetic carbohydrate: protein antigen was then emulsified in complete Freund's adjuvant and injected into the footpads of New Zealand White rabbits. A population of the resulting anti-conjugate antibodies displayed some binding properties analogous to concanavalin A, the carbohydrate-binding protein of the jack bean. The antisera weakly percipitated mannans from Saccharomyces rouxii, S. cerevisiae, and an alpha-(1 leads to 3)-mannopyranosyl transferase-deficient mutant from Kluyveromyces lactis Y58a. These polysaccharides, possessing side chains containing terminal alpha-(1 leads to 2)-mannobiosyl residues, produce strong percipitation reactions with concanavalin A. In addition, various saccharides were tested for their ability to inhibit the interaction of anti-conjugate antisera with alpha-(1 leads to 2)-mannobiosyl-containing polymers. p-Nitrophenyl 2-O-alpha-D-mannopyranosyl-alpha-D-mannopyranoside showed a strong complementarity for the binding sites of both the anti-conjugate antisera and concanavalin A. However, the antibody failed to bind a concanavalin A-reactive mouse fibrosarcoma or to stimulate mitogenesis of human peripheral lymphocytes.

Animals

Canine pulmonary angiotensin-converting enzyme. Physicochemical, catalytic and immunological properties.

Antiontensin-converting enzyme (peptidyldipeptide hydrolase, EC 3.4.15.1) has been solubilized from canine pulmonary particles and purified to apparent homogeneity. A value of approx. 140000 was estimated for the molecular weight of the native and the reduced, denatured forms of the enzyme. No free NH2-terminal residue was detected by the dansylation procedure. Carbohydrate accounted for 17% of the weight of the enzyme, and the major residues were galactose, mannose and N-acetylglucosamine with smaller amounts of sialic acid and fucose. Removal of sialic acid residues with neuraminidase did not alter enzymatic activity. The enzyme contained one molar equivalent of zinc. Addition of this metal reversed stimulation and inhibition of activity observed in the presence of Co2+ and Mn2+, respectively. Immunologic homology of pure dog and rabbit enzymes was demonstrable with goat antisera. Fab fragments and intact IgG antibodies displayed similar inhibition dose vs. response curves with homologous enzyme, whereas the fragments were poor inhibitors of heterologous activity compared to the holoantibodies. The canine glycoprotein was much less active than the rabbit preparation in catalyzing hydrolysis of Hip-His-Leu. In contrast, the two enzymes exhibited comparable kinetic parameters with angiotensin I as substrate.

Amino Acid Sequence

The characterization fo the B-cell repertoire specific for the 2,4-dinitrophenyl and 2,4,6-trinitrophenyl determinants in neonatal BALB/c mice.

The (B-cell) repertoire responsive to the DNP and TNP haptenic determinants in BALB/c neonates was analyzed in terms of the specificity of stimulation of neonatal B cells as well as the diversity of specificities available in neonatal populations. The results indicate that the parameters of stimulation of neonatal B cells are similar to those of nonimmune adults, particularly in the exquisitely specific stimulatory process which readily discriminates between haptens as closely related as 2,4-dinitrophenyl (DNP) and 2,4,6-trinitrophenyl (TNP). The clonotypes of monoclonal anti-DNP and anti-TNP antibodies derived from isolated neonatal BALB/c splenic B cells in fragment culture were analyzed by isoelectric focusing. During the first 4 days of neonatal life almost all of the anti-DNP-specific clones were of clonotypes displaying IgM antibodies with pI's of 5.05, 5.25, or 5.55. These could be distinguished from clonotypes responding to TNP which were also predominantly of three distinct pI's, 5.00, 5.15 or 5.40. These clonotypes, which represent the vast majority of the DNP- and TNP-specific antibody capability during the first 4 days of life, represented less than half of the clones by day 6 and were a small minority by day 9. The observation that individual 1--4-day-old donors had many B cells representative of a given predominant clonotype is evidence for cellular precommitment of specificity and indicates that clones of precommitted B cells exist as the products of normal, antigen-independent, generative processes. The observation of frequently recurring clonotypes in inbred neonates attests to the "germ line" origin of these clonotypes; however, variance in the occurrence of these clonotypes from donor to donor implies a random element in their expression. The finding that several clonotypes occur repeatedly in high numbers early in neonatal development, while other clonotypes occur only sporadically at early times, has been interpreted as a reflection of a sequential ontogenic expression of clonotypes. Thus the DNP- and TNP-specific clonotypes which predominate in neonates may be seen as representative of a total of 5,000-10,000 clonotypes which are expressed as early as the 15th to 17th day of gestation while most clonotypes appear after the 18th day of gestation.

Age Factors

Serological specificities of polysaccharides from four Salmonellae sharing "O" factor 8.

S. virginia (8) and S. newport (6.8) induced in sera of hyper-immunized rabbits antibodies which precipitated the respective homologous and heterologous polysaccharides as well as the polysaccharides from S. blockley (6.8) and from S. emek (8.20) by homogeneous lines of, apparent, serological identity. S. blockley, sharing with S. newport the same "O" factors, induced however two antipolysaccharides of which only one was identical with that of S. virginia. Different proteinic carriers were found to be responsible for the two induced antipolysaccharides. S. emek (820) induced antipolysaccharide antibodies which displayed a reaction of partial identity with the heterologous polysaccharides, in contrast to the serological homogeneity of precipitation, shown by the S. emek polysaccharide against the heterologous sera. The existence of a more complex structure of the S. emek polysaccharide, of which a small determinant is in common with the heterologous polysaccharides and is associated with a common proteinic carrier explains these different reactions.

Animals

Lymphocytes from synovial tissue of a boy with X-linked hypogammaglobulinemia and chronic polyarthritis.

Lymphocytes were eluted from synovial tissue of a boy with X-linked hypogammaglobulinemia and chronic polyarthritis. The cell suspension contained 53% lymphocytes and 28% peroxidase-positive, macrophagelike cells, No B lymphocytes, 83% T lymphocytes, and 10% Fc-receptor-bearing lymphocytes were detected. Lymphocyte transformation was induced by polyclonal mitogens (phytohemagglutinin and pokeweed mitogen) whereas no response to antigens (purified protein derivative and Candida albicans antigen) was obtained. The eluted cells displayed antibody-dependent cytotoxicity.

Agammaglobulinemia

Bullous disease of childhood: report of a case demonstrating antibasal cell antibody.

This report describes a child with protracted bullous disease responsive only to high doses of steroids, who on immunofluorescent testing, consistently displays antibasal cell antibody. The child had been treated with penicillin a week prior to the development of the bullous disease. The etiologic possibility of this drug history in the evolution of the bullous disease is raised, with particular respect to recent reports of similar circulating antibody in drug reactions.

Antibodies

Cytotoxic antibody to cells infected with measles virus in serum and cerebrospinal fluid of multiple sclerosis and control patients.

Sera and cerebrospinal fluids (CSFs) from 66 patients selected from a larger sample of multiple sclerosis (MS) and control patients were studied for presence of complement-dependent cytotoxic (CT) antibody against baby hamster kidney cells infected with measles virus, strain Lec. The MS group contained 26 patients with clinically definite disease and 7 with probable MS. Seventeen of the 33 patients selected from the MS group had hemagglutination-inhibiting (HI) antibody to measles virus in their CSFs. Specimens from 33 control patients with other identifiable neurological disorders were matched according to the time of specimen sampling and with the age of the donors. Seven of the controls had HI CSF antibody. The serum CT geometric mean antibody titer of the MS group was approximately twofold higher than that of the control group. Forty-two percent of the MS group and 18% of the control group had CT antibody in the CSF. With the exception of the ratio of one control patient, the serum/CSF ratios of CT antibody from all patients were 128 or less. Nine CSFs (six MS and three control specimens) had CT antibody but no detectable HI antibody. Conversely, 12 CSFs (eight MS and four control specimens) had HI antibody but no detectable CT antibody. Five patients in the MS group with both kinds of CSF antibodies had reduced CT ratios but normal HI ratios. The results suggest that the two tests detect CSF antibodies reactive with different antigens. In this study, where less than half of the MS patients displayed CSF CT antibody, it is unlikely that such antibodies play an active role in the pathogenetic mechanism operative in the disease.

Antibodies, Viral

The area-code hypothesis: the immune system provides clues to understanding the genetic and molecular basis of cell recognition during development.

Numberous studies of embryogenesis have provided evidence for highly specific cell-surface recognition phenomena. These include both the interactions of neighboring cells and the specific cellular migrations which occur as the developmental program of the embryo progresses. The area-code hypothesis elaborate here is an attempt to provide a framework for understanding cell-recognition phenomena in development. This hypothesis is based on extensive genetic, molecular, and cellular studies of the immune system. These studies suggest that the following events occur during the differentiation of antibody-producing cells. 1) Somatic cell lines of antibody-producing cells undergo a modification of their DNA as they become committed to synthesize a particular type of antibody molecule. This chromosomal modification event is probably a DNA translocation which leads to a somatic rearrangement of certain antibody genes. 2) In each of the specific cell lineages the new arrangement of DNA is inherited by all subsequent generations of cells. 3) The developmental programs which control these genetic alterations may be employed in a programmed and reproducible fashion. This programming of antibody development is suggested because different embryos appear to become committed to the production of identical antibody molecules in the same developmental sequence. 4) Antibody molecules are initially displayed on the cell surface where they serve as highly specifici receptors to trigger the cell to proliferate and differentiate upon interacting with appropriate external molecular signals. 5) Antibody-producing cells display combinations of different molecules on their surfaces which cause each of a very large number of different cells to interact differently with their environment. 6) The genes which code for many of these cell-surface molecules are organized into multigene families. These observations as well as information from other developmental systems have led us to propose the area-code hypothesis. This hypothesis is concerned with the structure, function, and regulation of cell-surface molecules that mediate recognition phenomena during embryogenesis. Area-code molecules are cell-surface molecules which are involved in the specific recognition phenomena during growth and development. These molecules provide cells with distinct cell-surface addresses or phenotypes, and provide the basis for the specificity in cell-cell recognition during cell migrations and cell-cell interactions, as well as serving as receptors for diffusible differentiation signals. The area-code hypothesis has 3 main postulates. i) There is a progressive display of specific combinations of area-code molecules on the surfaces of cells during development. ii) The genetic programs which determine the specific expression of area-code molecules are in part controlled by DNA modifications. These chromosomal modifications are believed to channel cells into specific lineages uith progressively restricted developmental options...

Animals

Isolation of material displaying insulin-like immunological biological activity from the brain of the blowfly Calliphora vomitoria.

An insulin-like material from the brain of the blowfly Calliphora vomitoria was partially purified by acid alcohol extraction, gel filtration and ion-exchange cellulose chromatography. In addition, the RF value on polyacrylamide-gel electrophoresis was determined. The material was characterized by its ability to cross-react with bovine insulin antibody and by displaying diminished immunoreactivity on dilution. It displaced specifically bound 125I-labelled insulin from rat liver plasma membrane insulin receptors and displayed insulin-like biological activity on the isolated rat fat-cell. Within 30 min of injection into Calliphora, made hypertrehalocaemic and hyperglucaemic as a result of median neurosecretory cell removal, it caused the concentrations of both sugars to return to normal. The hypothesis is put forward that the median neurosecretory cells are the source of the material.

Animals

[Immunoepidemiological observations on the duration of post-vaccinal immunity in children vaccinated against measles].

In the course of 4 years the authors carried out an immunological and epidemiological observation over 4719 children which attended creches, kindergartens and schools, and were vaccinated with live measles vaccines L-16 and ASC in 1967--1972. A stable persistence of immunity was revealed in the majority of children vaccinated against measles which responded to the vaccination by the formation of humoral antibodies. Among these groups an insignificant number of persons with the appearance of measles sensitivity was noted during the observation period. The quality of the preparation, conditions of its storage, use, and different errors during the vaccination influenced the efficacy of the vaccination. Children immunized with the low-immunogenic series of the vaccine whose blood sera failed to display any specific antibodies in the reaction with 1 AU of the antigen, as a rule, were the ones that contracted the disease.

Antibodies, Viral

[Investigations concerning the evidence of herpes simplex virus type 2 (HSV-2) antibodies in patients with carcinoma of the cervix (author's transl)].

The neutralizing antibodies to HSV-1 and HSV-2 were determined in the sera of 128 patients. Infection was detectable in nearly 100% of the cases in each of the three investigated groups (patients with carcinoma of the cervix, female patients with chronic recurrent HSV infection in the genital area and a control group without and history of HSV infection). The percentage of patients displaying HSV-2 antibodies in the group with carcinoma of the cervix (38%) is significantly higher than in the control group (12%). The results are compared with the findings of other authors and the possible causal significance of HSV in carcinogenesis is discussed.

Adult

The influence of maternal immunoglobulin-G-antibodies on indirect haemagglutination in newborns.

High antibody titers against Escherichia coli were found in 100 randomly selected pregnant women by means of indirect haemagglutination (IHA). After birth, sera from the umbilical vein of the newborns were also tested. It was found that the indirect haemagglutination titers of the children were strongly influenced by the IgG which had been transferred via the placenta. Twenty-two sera of newborns showed an increased IHA-titer against E. coli, but only seven children displayed specific IgM antibodies, determined by indirect immunofluorescence. After chromatographic separation of the sera into IgG and IgM fractions, it was demonstrated that isolated antibodies of the IgG type alone can produce increased IHA titers. The assumption that the indirect haemagglutination is determined almost exclusively by antibodies of the IgG type is unfounded. Therefore, indirect haemagglutination is not suitable as a screening-test for newborns.

Antibodies, Bacterial

Antigens in penicillin allergy. I. A radioimmunoassay for detection of penicilloylated protein contaminants in penicillin preparations.

This communication presents a sensitive and discriminative method for detection of protein impurities in penicillin preparations. Antibodies against various penicilloyl derivatives of high avidities and specificities raised in rabbits were coupled to microcrystalline cellulose. The amount of penicilloyl antigen present in a sample was calculated from the relative uptake of a radioiodinated penicilloylated albumin competing with the sample for binding to the antipenicilloyl immunosorbent. As little as 0.048 pmol/ml of penicilloylated human serum albumin could be detected. The accuracy of the determination was within +/- 23% (p less than 0.05). The pronounced specificities against the penicillin side chains demonstrated by the various immunosorbents were not displayed by the antibodies in passive cutaneous anaphylaxis experiments in guinea pigs. Furthermore, the immunosorbents showed the same pattern of specificity against monomeric penicillins as for penicilloylated proteins, but the former were considerably less efficiently recorded. The relatively small quantities of protein impurities in penicillin preparations, however, necessitated a separation from penicillin prior to analyses with the RIA. This was accomplished by fractionation on Sephadex G-50 fine, ginving a recovery of 80-90% of 0.1-2.5 ppm of penicilloylated protein.

Ampicillin

Search for correlates of resistance to virulent challenge in mice immunized with Coxiella burnetii.

Mice immunized with live phase I or phase II Coxiella burnetii, with killed phase I or phase II organisms or with trichloroacetic acid (TCAE) or phenol (PE) extracts were resistant to intraperitoneal infection with phase I C. burnetii irrespective of whether or not they displayed phase I antibody response at the time of virulent challenge. Increased phagocytosis of purified phase I organisms by blood leukocytes or peritoneal exudate cells (PEC) was noticed only in mice with phase I agglutinating antibodies in their sera or peritoneal washings. Passive transfer of resistance was made possible only by sera containing phase I agglutinating antibodies. Adoptive transfer of immunity by spleen cells, but not by PEC, was achieved providing that these cells were taken from mice immunized with live phase I C. burnetii.

Animals