Search PubMed⌕ Search

Biomedical subjects

E Monostori

Publications and source records attributed to E Monostori.

32 records · Page 2Linked to original sources
PubMed1990

The mouse erythrocyte binding receptor is expressed on human keratinocytes.

Immunocytes and different types of epidermal cells share cell surface antigen characteristics e.g. keratinocytes react specifically with the Leu 11 (CD16) monoclonal antibody and they express MHC class II and OKM5 (CD36) antigens after gamma-interferon stimulation. The present study provides evidence that a subpopulation of human keratinocytes most probably at a certain stage of differentiation, possesses the mouse erythrocyte binding receptor the marker of a human B lymphocyte subset. This finding is a further evidence for the relationship between the epidermis and the immune system.

Animals↗
PubMed1987

Cortical thymocyte differentiation in thymomas: an immunohistologic analysis of the pathologic microenvironment.

Four monoclonal antibodies (BH11, T2/30, AG3, and BC3) were produced against different epithelial components of the normal thymus. An immunohistologic study was performed on 13 thymomas by the use of these and other stromal and lymphocyte-specific reagents. The aim of this study was to find possible relationships between the proliferating thymoma epithelial cell type and the T cell composition of thymomas. Our results indicate that cortical T cell differentiation is present in thymomas, and that this differentiation is induced in the absence of detectable levels of MHC class II antigens on the epithelial component in most cases. The role of the MHC class II antigens cannot be excluded, however, because these antigens were always present on macrophages. Analysis of the selected group of thymomas, each of which contained epithelial cells homogeneously stained by at least one of the described monoclonal antibodies, showed that the cortical type T cell inducer capacity of thymomas is independent of the epithelial type predominant in the tumor.

Antibodies, Monoclonal↗
PubMed1986

Monoclonal antibody-recognizing cone visual pigment.

Monoclonal antibodies were raised to a crude photoreceptor-membrane suspension from chicken retinas. Clones producing antibodies against cone outer segments were selected by screening with immunocytochemistry on semithin sections of the retina. One monoclonal antibody, called COS-1, specifically labelled outer segments of double cones and one type of single cones; outer segments of rods and several single cones were not stained. On immunoblots of retinal photoreceptor membranes, this antibody recognized a protein with an apparent molecular mass of 33,000. The visual pigment character of the 33,000 protein was indirectly established by another monoclonal antibody, OS-2, which labelled all outer segments on semithin sections and four bands (33,000-, 36,000-, 38,000-40,000- and a composite band between 66,000-72,000 MW) on immunoblots. Of these, the 36,000- and the 72,000 MW protein bands were identified with an anti-rhodopsin polyclonal antibody as rhodopsin monomer and dimer. Monoclonal antibody OS-2 is assumed therefore to represent an antibody against a common epitope of all visual pigments of the chicken. The monoclonal antibody COS-1 was found to bind to certain cone outer segments of many other vertebrate species as well.

Animals↗
PubMed1985

Purification and characterisation of chicken brain hypoxanthine-guanine phosphoribosyltransferase.

Hypoxanthine-guanine phosphoribosyltransferase enzyme (EC 2.4.2.8) from chicken brain has been purified 10 000-fold to homogeneity. The molecular mass of the native enzyme is 85 kDa, with four subunits, each of 26 kDa, and exerts its maximum activity at pH 10.0. The Km values for hypoxanthine and guanine are 5.2 and 1.8 microM, respectively. The half-life of the enzyme is 30 min at 85 degrees C. Monoclonal antibodies were raised against the native purified enzyme and were used for purification of enzyme to homogeneity. The monoclonal antibody did not bind to the active centre of the enzyme.

Animals↗
PubMed1985

Heterogeneity of chicken photoreceptors as defined by hybridoma supernatants. An immunocytochemical study.

Immune cells producing antibodies to chicken photoreceptor membranes were fused with myeloma cells and supernatants of the resulting hybridoma cells were used to test various types of photoreceptor cells in the chicken retina by means of immunocytochemistry. A polyclonal antibody raised against the protein component of bovine rhodopsin was also used. Outer segments of various photoreceptor cells were labelled by the following antibodies: rods were positive with the anti-rhodopsin antibody, both members of the double cones were stained by supernatant A1, while one type of single cones (designated as type A) was specifically labelled by supernatants A5, B3 and D6. The other type of single cones (type B) reacted with anti-rhodopsin and supernatant A1. The results indicate that there are distinct differences in the molecular structure of various photoreceptor outer segments.

Animals↗
PubMed1984

A new method in criminology: use of ELISA to detect AFP on different materials with monoclonal anti-alpha-fetoprotein.

A new method has been introduced to distinguish normal adult serum stains from fetal or newborn serum and amniotic fluid stains with ELISA in cases of criminal abortion and infanticide. The method is based on the sensitive detection of alpha-fetoprotein (AFP) by a two-site enzyme immunoassay (EIA) following its elution with high efficiency from different materials (e.g., cotton, paper, synthetic fabric, or glass) by phosphate-buffered 0.5 M NaCl solution.

Adult↗
PubMed1984

Isolation of the human myelin basic protein by immunoaffinity chromatography with a monoclonal antibody.

Immunoaffinity chromatography has been developed for the isolation of the human myelin basic protein (MBP). The method is based on the use of a monoclonal antibody which was produced to bovine MBP, cross-reacting with human MBP. The protein isolated from acidic extracts of the brain proteins was shown to be native MBP by its immunochemical reactivity, by its ability to elicit experimental allergic encephalomyelitis and by its mol. wt (18,600 +/- 400). It represented a single-band purity after hypersensitive silver staining. The MBP isolated by the method described represents a higher purity than that of the MBP purified by conventional multistep biochemical separation techniques.

Animals↗
PubMed1979

Studies of pre- and postimmunization antibodies of sheep.

Serum samples were taken serially from three nonimmunized sheep over a long period of time. Antibodies to human serum albumin (HSA), ovalbumin (OA) and FITC were separated from the samples. Than, two of the animals were injected with HSA+ complete Freund's adjuvant, the third with adjuvant without antigen. Serial postimmunization serum samples were subjected to the same procedures as the pre-immunization ones. The specific antibodies increased in concentration, and only the postimmunization antibody population was able to precipitate. In the presence of the antigen, the postimmunization antibodies bound to the Fc receptors of lymphocytes to an increased degree. There was no difference between pre- and postimmunizaton antibody populations either in complement-activating capacity or in the quantity of antigen necessary for reaching antigen-antibody equivalence. Isoelectro-focusing showed no new bands which would indicate antibodies different from the pre-existing ones. However, changes were observed in the relative participation of the antibodies forming different bands. No sharp limit was observed between pre- and postimmunization antibody populations. The Ig increment demonstrated after immunization was accompanied by a similar increment in the specific antibodies tested in the animal that had not given antigen, but not in the others. The authors attribute a role to humoral antibodies already in the earliest phase of immune response.

Animals↗
PubMedDate not supplied

Phenotypic changes of the subseptal thymic epithelium in myasthenia gravis.

We studied the phenotype of thymic epithelial cells of hyperplastic thymuses from myasthenia gravis, (MG) patients, in respect to the expression of a 64 Kd protein defined by the monoclonal antibody T2/30 and normally present in the whole cortical epithelium. In hyperplastic thymuses, epithelial cells bordering the basement membrane (subseptal epithelial layer) were consistently T2/30-negative whereas other cortical epithelial cells did bind the monoclonal antibody. These results clearly demonstrate a phenotypic change in hyperplastic thymus of MG patients. Such change might be correlated with the damage of basement membrane previously reported in myasthenia gravis hyperplastic thymuses, and eventually with an invasion of B cells into the parenchyma of the organ.

Adult↗
PubMedDate not supplied

Branched polypeptides as antigens for influenza virus hemagglutinin and T-cell receptor subunits.

The multiple antigenic peptide (MAP) method was applied to improve the immunogenicity of synthetic peptides representing distinct regions of the influenza virus hemagglutinin (HA). A tetrameric MAP with multiply incorporated overlapping B- and T-cell epitopes was combined with a particular HA sequence representing the slightly modified fusion peptide on the C-terminus of the Lys core (MAP-1). As a result of repeated injections of BALB/c mice with MAP-1 but not with the monomeric HA1C[Arg] peptide, the appearance of MAP-1-specific antibodies crossreactive with the acid-pretreated virus could be observed. In vitro studies revealed the potency of the MAP-1 structure to induce proliferation of HA1C[Arg]-primed T-cells, and in vivo studies demonstrated the protective feature of the immune response elicited by MAP-1 and to a lesser extent by the monomeric HA1C[Arg]. The increased level of MAP-1 specific antibodies upon viral challenge shows the activation of MAP-1-specific B- and/or T-cells. The advantage of the previously verified FP3 helper T-cell epitope included in MAP-1 was further utilized to synthesize chimeric structures comprising short fragments of the zeta of (MAP-2) or delta (MAP-3) subunits of the T-cell antigen receptor (TCR) complex. The selected peptides of the zeta and delta-chain regions failed to elicit an antibody response in BALB/c mice as tetra- or octamers, but the inclusion of the modified fusion region resulted in an immunogenic construction.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗