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Biomedical subjects

N A Staines

Publications and source records attributed to N A Staines.

At least 73 records · Page 4Linked to original sources
PubMed1988

Tolerogenic activity of polymerized type II collagen in preventing collagen-induced arthritis in rats.

Rats were exposed parenterally or pergastrically to polymerized type II collagen (POLCII) and became resistant to the subsequent induction of disease with arthritogenic type II collagen (CII) administered intradermally in Freund's incomplete adjuvant (FIA). POLCII was prepared by cross-linking native soluble arthritogenic CII, from bovine nasal septal cartilage, with glutaraldehyde. POLCII injected intradermally in FIA did not induce arthritis. Animals treated in this manner were resistant for a period of at least 100 days to induced disease. The change in the properties of the CII from an arthritogen to a tolerogen was related to the amount of glutaraldehyde (used to polymerize the CII) which was assumed to control the extent of cross-linking of the CII. Highly cross-linked POLCII administered pergastrically, like soluble CII, was not arthritogenic but was tolerogenic, inducing a state of unresponsiveness to a challenge with arthritogenic CII. In general serum anti-CII antibody levels were higher in arthritic than in tolerized non-arthritic rats. It is concluded that the breaking of self-tolerance to CII depends upon its physical state. When polymerized and insoluble, a form analogous to that in which it exists naturally, it is tolerogenic.

Animals↗
PubMed1986

Gastric administration of type II collagen delays the onset and severity of collagen-induced arthritis in rats.

Rats were per-gastrically dosed by gavage with collagen type II (CII) in solution and were shown, as a result, to be subsequently resistant to the induction of disease by CII administered parenterally in Freund's incomplete adjuvant. Disease onset was delayed and the severity was reduced. There was no concomitant reduction in the systemic antibody response to CII. Gavage with CII did not in itself induce systemic anti-CII antibodies and did not cause symptoms of arthritis. The results indicate that materials specifically cross-reactive with autoantigens can be absorbed through the gut and can modify susceptibility to autoimmune disease.

Animals↗
PubMed1985

A monoclonal antibody based solid-phase enzyme-binding assay to measure levels of placental alkaline phosphatase in serum of women during pregnancy.

Monoclonal antibodies raised against highly purified placental alkaline phosphatase (PALP) reacted specifically with PALP and were found not to cross-react with the liver, kidney and intestinal enzymes. One of these antibodies (AP-3) was selected to develop an enzyme-binding assay to measure levels of PALP in the sera of 11 women throughout pregnancy. PALP activity rose sharply after 28 weeks of gestation reaching a peak at delivery followed by an immediate drop within 4 days to values approaching non-pregnant levels. The potential of using this assay as an index of placental function to monitor progress of a pregnancy is discussed.

Alkaline Phosphatase↗
PubMed1985

Five groups of antigenic determinants on DNA identified by monoclonal antibodies from (NZB X NZW)F1 and MRL/Mp-lpr/lpr mice.

A library of monoclonal antibodies (MCA) reactive with DNA was derived from mice with lupus-like disease. The combining reactions of the antibodies was determined by ELISA, precipitation assay and indirect immunofluorescence assay on cells. On the basis of their reactions in these assays, the MCA have been classified into five taxonomic groups. MCA in Group I react with conformational determinants on double-stranded DNA (dsDNA); those in Group II with conformational backbone-dependent sugar-phosphate determinants on dsDNA and single-stranded DNA (ssDNA); those in Group III with determinants predominantly expressed on ssDNA; those in Group IV with base-dependent determinants on ssDNA, and those in Group V with determinants on both DNA and RNA. It is concluded that antibodies which react with DNA are collectively of limited heterogeneity with regard to their specificity. The study illustrates how, upon traditional interpretation, different assay systems may give discordant results in the assignment of specificity to antibodies reactive with DNA.

Animals↗
PubMed1985

A key role for fibronectin in the sequential binding of native dsDNA and monoclonal anti-DNA antibodies to components of the extracellular matrix: its possible significance in glomerulonephritis.

The interactions of DNA, monoclonal anti-DNA autoantibodies and isolated purified components of the extracellular matrix (ECM) were studied in a solid phase model system. Binding of DNA to each of the components was assessed using monoclonal antibody and enzyme conjugated antiglobulin in direct binding and inhibition assays. Each of the genetically distinct collagens (Types I-IV), proteoglycan monomer and laminin, bound ssDNA, but dsDNA bound significantly only to fibronectin. When used in an inhibition system, fibronectin linked DNA and anti-DNA antibodies to the collagens; it had a differential effect on the binding of ssDNA and dsDNA to a Type IV collagen matrix, the most striking feature being a 100 fold increase in dsDNA binding to Type IV collagen in the presence of fibronectin. It is likely that fibronectin binds dsDNA to collagen by separate binding domains for these molecules, and that this may be involved in the deposition of DNA in kidneys in some forms of glomerulonephritis.

Animals↗
PubMed1985

Shared idiotypes are expressed on mouse and human anti-DNA autoantibodies.

The expression of common idiotypes on human and mouse anti-DNA monoclonal autoantibodies made by hybridomas was examined by their competitive binding to anti-idiotype antibodies. Some murine autoantibodies inhibited the binding of a human anti-DNA autoantibody 16/6 to monoclonal or polyclonal anti-idiotypic antibodies. Another human antibody (134) was not inhibited in its binding to homologous anti-idiotypic antibodies. The expression of the human 16/6 idiotype on mouse antibodies was restricted to those that had a specificity similar to the 16/6 antibody itself, their major properties being that they reacted more strongly with single stranded DNA (ssDNA) than double stranded DNA (dsDNA). One mouse antibody expressing the 16/6 idiotype also bound weakly to RNA. The results imply structural similarities between the binding sites of the antibodies in the two species, and are consistent with evolutionary conservation of V genes coding for primitive ancestral antibodies that react with DNA and become diversified through somatic mutation.

Animals↗
PubMed1985

Human monoclonal antibodies from patients with rheumatoid arthritis: cross reactions against cellular constituents.

Hybridization of peripheral blood lymphocytes from patients with rheumatoid arthritis has yielded 14 monoclonal antibodies which react with cultured human epithelial cells. Immunofluorescence staining identifies at last five different types of antibody. Solid phase immunosorbent assays show a variety of cross-reaction patterns with nucleic acids, proteoglycan, cardiolipin and plastic, confirming that the various antibodies react with epitopes which are at least slightly different. These conclusions are confirmed by SDS gel electrophoresis and immunoblotting on epithelial cell extracts. Similar antibodies previously found in association with lupus-like disease have been thought to be representative of the high antinuclear antibody response characteristic of lupus. Our data are more consistent with the hypothesis that all or many of these antibodies are part of the normal inflammatory response.

Antibodies, Monoclonal↗
PubMed1985

Suppression of collagen type II-induced arthritis by transfer of lymphoid cells from rats immunized with collagen.

Rats were immunized with type II collagen to induce polyarthritis. Spleen and lymph node cells were taken at various times and transferred to normal syngeneic animals. Disease was not observed in recipients of cells taken from donors either during the pre-clinical phase or the acute clinical phase of the disease. However, arthritis could not be induced in the recipient animals that had received cells taken from donors during the preclinical phase. Animals receiving cells from donors with clinical disease appeared to have a normal susceptibility to disease induced subsequently. In contrast with the differences in their susceptibility to induced disease, all recipient animals made unmodified antibody responses to a challenging injection of type II collagen. The results showed that before the appearance of clinical disease in CII immunized rats, there were cells in the spleen and lymph nodes that inhibit the development of disease but not antibody responses.

Animals↗
PubMed1984

Glomerulonephritis induced by pre-formed immune complexes containing monoclonal antibodies of defined affinity and isotype.

The work presented here represents the first report of the induction of experimental immune complex (IC) disease in mice using monoclonal antibodies (MoAb) derived from somatic cell hybridization. IC were formed using two antigens of either high (DNP19BSA) or low (DNP4BSA) epitope density and five MoAb (four IgGl with varying affinities for the dinitrophenol hapten and one IgM with a similar affinity to that of the lowest affinity IgGl). Circulating levels and sizes of IC were dependent on the affinity of the antibody component of the complex. When antigen of high epitope density was used, the glomerular localization of injected IC was diffuse mesangial for the IgM antibody, focal mesangial for the highest affinity IgG and diffuse, and predominantly capillary for the low affinity IgG antibodies. Subepithelial electron dense deposits were observed only with IC made with the low affinity IgG antibodies. When IC containing antigen of a lower epitope density were injected, localization was only observed with IC made near equivalence. Deposition of these IC was less prominent than that found when IC containing antigen of higher epitope density were injected. The relevance of these findings to the pathogenesis of glomerulonephritis is discussed.

Animals↗
PubMed1984

The anti-arthritic and immunosuppressive effects of cyclosporine on arthritis induced in the rat by type II collagen.

The influence of cyclosporine (CsA) on the induction and pathogenesis of type II collagen-induced arthritis has been investigated in inbred and outbred Wistar rats. The proportion of animals developing disease and the severity of disease they developed were both diminished by treatment with CsA. These effects were accompanied by a marked suppression of the antibody response to both the immunizing collagen and also to rat type II collagen. CsA treatment also resulted in a decreased accumulation of lymphocytes in arthritic joints. The results indicate that the anti-arthritic and immunosuppressive effects of CsA probably result from a modification of both systemic antibody-mediated and local cell-mediated immunity.

Animals↗
PubMed1983

Separation of two molecular species of the Sm antigen by affinity chromatography with murine monoclonal and human anti-nuclear autoantibodies.

Nuclear ribonuclear protein (nRNP) and Sm were extracted from a 30-60% ammonium sulphate fraction of rabbit thymus extract by affinity chromatography. Immunoadsorbent columns were prepared from IgG extracted from an anti-nRNP serum, an anti-Sm serum and two monoclonal autoantibodies derived from a MRL/lpr mouse. All four immunoadsorbents isolated both nRNP and Sm antigens indicating that they exist as the 'nRNP/Sm complex' A species of Sm which did not bind to the anti-nRNP column and which was subsequently purified with the anti-Sm column was termed 'free Sm'. The Sm in the complex and free Sm were immunologically identical on immunodiffusion and gave similar polypeptide bands on polyacrylamide gel electrophoresis. However, they differed in that complexed Sm was sensitive to heat and RNAase. These studies provide direct evidence of a physical association between the nRNP and Sm antigens and indicate an additional molecular species of Sm whose resistance to RNAase may be due to different associated RNA species.

Animals↗
PubMed1981

Collagen-induced arthritis in the rat: modification of immune and arthritic responses by free collagen and immune anti-collagen antiserum.

Inbred Wistar strain rats developed a polyarthritic disease when injected intradermally with Freund's incomplete adjuvant (FIA) containing porcine or bovine type II collagen (CII). In contrast, neither allogeneic rat CII nor porcine proteoglycan monomer were arthritogenic, although both were, to some extent, immunogenic. Animals passively transfused with immune serum containing anti-CII antibodies did not develop arthritis and showed greatly reduced anti-CII humoral immune responses (measured by an enzyme-linked immunosorbent assay) when the serum was administered at the time of and subsequent to challenge with arthritogenic porcine CII. Similarly, the intravenous injection of animals sequentially with 100 microgram soluble CII and 1 ml immune anti-CII antiserum, 9 and 8 days respectively before challenge with arthritogenic CII, abrogated the arthritic response and depressed the humoral anti-porcine CII and anti-rat CII antibody titres more than tenfold. It is concluded that the immune status of the recipient rats with respect to CII is crucially important in determining the nature of the immune and arthritic response to CII appropriately administered in FIA.

Animals↗
PubMed1979

The genetic control of antibody affinity. Evidence from breeding studies with mice selectively bred for either high or low affinity antibody production.

The genetic control of antibody affinity has been studied in mice selectively bred on the basis of the affinity of antibody they produce to protein antigens injected in saline. Two lines of mice have been obtained, one producing predominantly high and the other predominantly low affinity antibody. Breeding experiments have been performed with these two lines after ten generations of selection and the level and affinity of antibody to protein measured in parents, F1 hybrids and backcross offspring. The results indicate that antibody affinity is a genetically controlled parameter of the immune response and that this control is exerted independently of that controlling antibody levels. Furthermore, high and low affinity line mice have been typed for major histocompatibility complex antigens and the results show that the two lines are not significantly different. This therefore suggests that genes controlling antibody affinity are not linked to the major histocompatibility locus.

Animals↗