Biomedical subjects

A L Corbí

Publications and source records attributed to A L Corbí.

23 records · Page 2Linked to original sources

PubMed1991

Upregulated expression and function of VLA-4 fibronectin receptors on human activated T cells in rheumatoid arthritis.

The VLA-4 (CD49d/CD29) integrin is a cell surface receptor involved in the interaction of lymphoid cells with both extracellular matrix (ECM) and endothelial cells. We have investigated the expression and function of VLA-4 fibronectin (FN) receptors on T cells localized in the inflammed synovium of patients with rheumatoid arthritis (RA). A high proportion of T cells in both synovial membrane (SM) and synovial fluid (SF) expressed the activation antigens AIM (CD69) and gp95/85 (Ea2) as well as an increased number of VLA-4 alpha and beta 1 adhesion molecules, as compared with peripheral blood (PB) T cells from the same patients. Furthermore, the majority of these activated SF T cells were able to adhere to a 38-kD FN proteolytic fragment containing the connecting segment-1 (CS-1) specifically through VLA-4 receptors, whereas a significantly lower proportion of PB T cells displayed this capacity. Therefore, our results show that activated T cells selectively localize at sites of tissue injury in RA disease and provide evidence for the in vivo regulation of the expression and function of the VLA-4 integrin. This regulatory mechanism may enable T cells either to facilitate migration or to persist at sites of inflammation.

Adult↗

PubMed1985

A four-step sandwich radioimmunoassay for direct selection of monoclonal antibodies to allergen molecules.

A 4-step radioimmunoassay has been devised for direct identification of monoclonal antibodies (MAb) directed to IgE-binding molecules. Polyvinyl chloride wells coated with purified anti-mouse kappa chain MAb (187-1) were successively incubated with: (1) MAb-containing hybridoma supernatants, (2) allergen extract. (3) allergic patients' serum pool, and (4) 125I-labeled anti-human IgE antiserum, to detect MAb-allergen-IgE complexes. MAb to allergens from Parietaria judaica pollen and Dermatophagoides mites have been selected with this screening procedure. The affinity-purified allergen molecules completed the binding of IgE to allergen extracts coated to paper discs in a RAST inhibition assay, confirming the anti-allergen specificity of the selected MAb. This screening method is sensitive enough to allow detection of MAb directed to poorly represented allergens.

Allergens↗

PubMed1985

A competitive solid-phase radioimmunoassay for quantitation of the major allergen of Parietaria pollen.

A competitive solid-phase radioimmunoassay has been developed for quantitation of the major allergen of Parietaria judaica pollen. The assay is based on: (1) the ability of AC/1.1 monoclonal antibody to bind specifically to the P. judaica major allergen, and (2) the ability of crude pollen extracts or purified allergen to inhibit the binding of 125I-labelled allergen to solid-phase-bound AC/1.1 monoclonal antibody. The assay is sensitive enough to detect as little as 10 ng of allergen. A good correlation is found when the results obtained are compared with those produced by RAST inhibition (r = 0.95; P less than 0.001). Thus, this method can also be used for the estimation of the allergenic activity of P. judaica pollen extracts. The assay is easily completed in 2 h, allowing simultaneous analysis of a number of extracts.

Allergens↗

PubMed1985

Isolation of the major IgE-binding protein from Parietaria judaica pollen using monoclonal antibodies.

Allergen molecules from Parietaria judaica pollen, a widely distributed allergy inducer in Southern and Western Europe, have been studied using specific monoclonal antibodies (MAbs). MAbs against IgE-binding components were selected in a 4-step radioimmunoassay. Three different MAbs (AC/1.1, AC/7.1 and AC/15.1) were obtained which recognized epitope(s) located on a polypeptide of 10 Kd (Pj10). This polypeptide displayed the highest IgE-binding ability under either native or SDS-denatured conditions, as determined by immunoadsorption and immunodetection after SDS-PAGE, respectively. The Pj10-containing allergen, purified on an AC/1.1 MAb-Sepharose column, was able to inhibit most of the binding of specific IgE to the pollen extract coupled to paper discs in an inhibition radioallergosorbent test (RAST). The affinity-purified allergen exhibited the same immunoelectrophoretic behaviour as the native allergen.

Allergens↗

PubMed1985

Allergenic cross-reactivity among pollens of Urticaceae.

Common antigenic determinants have been observed between Parietaria and Urtica dioica pollen. The four Parietaria pollens selected (P. judaica, P. officinalis, P. lusitanica and P. mauritanica) are shown to possess a high allergenic homology. IgE-binding structures, homologous to the P. judaica main allergenic polypeptide (Pj10), were found in the other species by immunodetection. Monoclonal antibodies specific to the Pj10 polypeptide recognized proteins from the four Parietaria pollens. Skin prick test and RAST inhibition yielded results that also indicated a high allergenic cross-reactivity among these pollens, with homologous peptides bearing common antigenic and allergenic determinants. On the other hand, U. dioica pollen showed only a slight allergenic similarity to Parietaria. The potential allergenic activity of these pollens is discussed.

Allergens↗