Search results for "Mono"
showing 10 items of 6843 documents
The role of the Thomsen-Friedenreich antigen as a tumor-associated molecule.
1990
The Thomsen-Friedenreich antigen (Gal-GalNAc) represents a tumor-associated molecule, which is assumed to be one of the few chemically well-defined antigens with a proven association with malignancy. In order to analyze the role of the carbohydrate structure Gal-GalNAc for gastrointestinal tumors, we immunized Balb/c mice with MCF-7 breast tumor cells together with synthetic Gal-GalNAc linked to a BSA carrier. One monoclonal antibody (82-A6) was established which recognizes the Thomsen-Friedenreich antigen according to the biochemical and serological analysis presented here. In contrast to the studies performed in the past, immunohistochemical results using this antibody 82-A6 did not exhib…
General considerations in the interpretation of I-J genetic restrictions: evidence that the antigen-binding chain of antigen-specific T-suppressor fa…
1987
SUMMARY (CBA × B10)F1 [(H-2k x H-2b)] mice produce two types of antigen-specific T-suppressor factor (TsF), which can be separated by affinity chromatography on anti-I-J monoclonal antibody. After reduction and alkylation, both chains of F1 TsF are required for biological activity. However, the antigen-binding chain (AgBC) of F1 TsFk (AgBCk) is only complemented by I-Jk and likewise for F1 TsFb. In other words, interchain complementation shows the same genetic restriction in interchain complementation in parental and F1 mice. F1 TsF bearing, for example, I-Jk (TsFk), interacts with haptenized ‘antigen-presenting cells’ (‘APC’) of both parental haplotypes, and may be described as showing dua…
C1q-bearing immune complexes detected by a monoclonal antibody to human C1q in rheumatoid arthritis sera and synovial fluids
1991
Using a monoclonal antibody directed against the C-chain of human C1q, we detected C1q-bearing immune complexes (IC) in sera and synovial fluids of rheumatoid arthritis (RA) patients. In a sandwich-ELISA, C1q-bearing IC were captured by the solid-phase monoclonal antibody and then detected with peroxidase-labeled F(ab')2-antibodies to either human IgG or IgM. The results of this assay were compared to an ELISA-modification of the C1q-solid-phase binding assay (C1q-SPBA). C1q-bearing IC were detected in 81.1% of RA-sera and the 65.2% of RA-synovial fluids. IgG as well as IgM was present in 72.6% of the sera and 70% of the synovial fluids which were positive in both assays. Most RA sera that …
Fab fragments from a monoclonal antibody against a germ tube mannoprotein block the yeast-to-mycelium transition in Candida albicans.
1990
Fab fragments prepared from the immunoglobulin G monoclonal antibody (MAb) 4C12, which reacts with a determinant expressed on the hyphal extension of germ tubes of Candida albicans, inhibited germ tube formation, but intact MAb 4C12 did not. Indirect immunofluorescence showed a punctate binding pattern on cells incubated with Fab fragments but a confluent binding on cells incubated with intact MAb 4C12.
Evaluation of the concept of heterology in a monoclonal antibody-based ELISA utilizing direct hapten linkage to polystyrene microtiter plates.
2005
A series of new heterologous haptens has been synthesized and used as coating haptens in an antigen-immobilized immunoassay with a monoclonal antibody against atrazine. Coating was achieved by covalently linking the different haptens to a glutaraldehyde network directly bound to the polystyrene surface of a standard 96-well microtiter plate. With the assay designed in the antigen-immobilized format with direct chemical linkage of the hapten to the solid polystyrene surface well-defined hapten densities were achieved in all experiments. The results of different experiments with different coating haptens were comparable. Using different heterologous haptens it appears that the concept of hete…
Interleukin-12 in Human Boutonneuse Fever Caused by Rickettsia conorii
2000
Interleukin (IL)-12 contributes to the resistance against a number of intracellular pathogens. We examined the potential biological role of IL-12 by studying peripheral blood mononuclear cells (PBMC), its production and its effect on cytokine synthesis in 20 Sicilian patients with boutonneuse fever (BF) caused by Rickettsia conorii. Data indicate that PBMC from acute BF patients were able to produce IL-12 in response to in vitro stimulation with rickettsial antigen (Ag): this production was higher than that detected in healed patients. Monocytes were the main source of IL-12 by PBMC from BF patients. IL-12 secretion by in vitro Ag-stimulated PBMC from BF patients was potentiated by recombin…
γδ cells involved in contact sensitivity preferentially rearrange the Vγ3 region and require interleukin-7
1997
Ptak and Askenase showed that both alphabeta and gammadelta cells are required for transfer of contact sensitivity (CS). This study confirms that day 4 immune cells depleted of gammadelta cells fail to transfer CS to trinitrochlorobenzene (TNP-Cl) systemically and demonstrates that administration of anti-gammadelta monoclonal antibodies (mAb) in vivo abolishes the CS reaction. Moreover, gammadelta cells accumulate at the antigen challenge site: these cells have the unusual phenotype CD8alpha+, CD8beta-, IL-4 R+ which we suggest is due to their state of activation. Following immunization with contact sensitizer on the skin, the absolute number of gammadelta cells increases in the regional ly…
Monoclonal antibodies to polysialic acid reveal epitope sharing between invasive pathogenic bacteria, differentiating cells and tumor cells
1987
Monoclonal antibodies (mAb) for rapid diagnosis and detection of invasive bacteria and identification of pathogenic factors in infectious disease are equally important in medical microbiology and clinical pathology and may even provide a breakthrough in basic medical and cell biology research. Such a situation evolved from the application of a unique mAb against the poorly immunogenic homopolymers of alpha 2,8-linked sialic acid of Escherichia coli K1 and meningococci group B capsules which could be derived from immune-hyperreactive NZB-autoimmune mice. The cross-reactivity of this mAb with identical polysialic acid (polySA) units of the neural cell adhesion molecule (N-CAM) revealed antige…
Antibodies to cell surface ganglioside GD3 perturb inductive epithelial-mesenchymal interactions
1988
Abstract Most epithelial sheets emerge during embryogenesis by a branching and growth of the epithelium. The surrounding mesenchyme is crucial for this process. We report that branching morphogenesis and the formation of a new epithelium from the mesenchyme in the embryonic kidney can be blocked by a monoclonal antibody reacting with a surface glycolipid, disialoganglioside G D3 . In contrast, a more than 10-fold excess of antibodies to adhesive glycoproteins (N-CAM, L -CAM, fibronectin) fails to inhibit morphogenesis. Although the anti-G D3 antibody affected epithelial development, the disialoganglioside G D3 was expressed not in the epithelium, but in the mesenchyme surrounding the develo…
Demonstration of P29, an oestrogen receptor-associated tumor marker, in human term placenta.
1991
A Mr29,000 serine phosphoprotein (P29) related to oestradiol receptor was studied in human term placenta with the use of a specific monoclonal antibody (D5). D5 was used with two different methods, immunohistochemistry and immunoradiometry. For immunohistochemistry, an indirect immunoperoxidase method was chosen to detect P29 in methacarn-fixed, wax-embedded sections. P29 was mostly confined to the syncytiotrophoblast surrounding placental villi, staining being positive in both cytoplasm and nuclei. The stroma of villi was negative. Content of P29 was uniformly high in crude placental cytosol, as measured by immunoradiometry assays. Specificity of D5 against P29 in placenta was tested by an…