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A S Townes

Publications and source records attributed to A S Townes.

At least 19 recordsLinked to original sources
PubMed1992

Collagen-induced arthritis in rats. Examination of the epitope specificities of circulating and cartilage-bound antibodies produced by outbred and inbred rats using cyanogen bromide-derived peptides purified from heterologous and homologous type II collagens.

To determine the number and location of antibody binding epitopes on type II collagen, outbred and inbred rats were immunized with chick, bovine, human, and rat type II collagen (CII, BII, HII, and RII); all sera were assayed for reaction with a panel of CB peptides purified and renatured from the immunizing collagen and from RII. Antibody reaction patterns (profiles) varied among individual outbred rats but were essentially constant over time and changed little after boosting. The strongest antibody reactions were to CB11, CB9-7, and CB12 followed by CB8, CB10, and CB6. Antibody profiles varied depending on the species of collagen used for immunization and the strain of rat immunized. Except for CB10, where antibodies were largely specific for heterologous collagens, antibodies reactive with all other CB peptides cross-reacted strongly with renatured rat CB peptides. Sera from inbred BB rats immunized with BII, CII, or HII reacted best with CB11, unlike antisera to RII that reacted strongly with CB9-7. Inbred LEW, COP, WKY, F344, and BUF rats immunized with BII reacted strongest with CB9-7 and variably with CB11 and CB12. BBxLEW F1 hybrid rats reacted almost equally with CB11 and CB9-7 producing an antibody profile intermediate to those elicited in the parent strains. Finally, antibodies reactive with rat CB11, CB9-7, and CB12 could be eluted from normal rat cartilage incubated in anti-BII serum; antibody eluate profiles generally paralleled the profile produced by the sera applied to cartilage. Taken together, these findings indicate that multiple antibody-reactive epitopes on type II collagen may be instrumental in the initiation of collagen-induced arthritis in rats, particularly shared or cross-reactive epitopes located within CB11, CB9-7, CB12, and CB8.

Animals↗
PubMed1992

Acceleration of onset of collagen-induced arthritis by intra-articular injection of tumour necrosis factor or transforming growth factor-beta.

We examined whether tumour necrosis factor (TNF) or transforming growth factor-beta 1 (TGF-beta 1) could alter the course of collagen-induced arthritis (CIA). Injection of 100 ng TNF or 500 ng TGF-beta 1 into ankle joints of normal rats induced a very limited inflammatory response, observable only upon histological analysis. However, when injected into ankle joints of rats 9 days after immunization with bovine type II collagen (CII), identical doses of TNF or TGF-beta 1 induced a sustained, clinically obvious inflammation and oedema that began within 8 h on average, as compared to 90 h in CII-immunized control rats given no injections or intra-articular injections of buffer. The incidence of arthritis at 2 weeks post-immunization was 100% for TNF-injected hindpaws, compared with 55% for the control groups, a statistically significant difference. In rats passively immunized with a subarthritic dose of affinity purified antibody to rat-CII, intra-articular injection of 100 ng TNF or 500 ng of TGF-beta 1 also induced intense, though transient arthritis. The rapid proinflammatory effects in CIA described in this study and the synergy demonstrated between anti-CII IgG and either cytokine, suggest that these cytokines can participate locally in the pathogenesis of arthritis.

Animals↗
PubMed1991

Immunity to type XI collagen in mice. Evidence that the alpha 3(XI) chain of type XI collagen and the alpha 1(II) chain of type II collagen share arthritogenic determinants and induce arthritis in DBA/1 mice.

To determine whether native bovine type XI collagen (BXI) is arthritogenic, five strains of inbred mice were immunized with BXI/CFA. Arthritis was not observed in any of these strains, though it was prevalent in DBA/1 and B10.RIII controls immunized with bovine type II collagen (BII). Antisera from BXI-immunized mice reacted with mouse type XI collagen (MsXI), weakly with the alpha-chains of BXI, and minimally with mouse type II collagen (MsII). However, antisera to BII reacted with MsII and MsXI, indicating antibodies to conformation-independent epitopes shared by alpha 1(II) and alpha 3(XI). Mice immunized with BXI containing a small amount of BII developed arthritis much like those immunized with BII; sera from these mice reacted with MsXI and MsII. Delayed-type hypersensitivity responses differed from IgG responses, i.e., BXI elicited responses to alpha 1(XI), alpha 2(XI), alpha 3(XI), and alpha 1(II); BII, to alpha 3(XI) and alpha 1(II) exclusively. To determine whether alpha 1(XI), alpha 2(XI), alpha 3(XI), and alpha 1(II) are arthritogenic, DBA/1J mice were immunized with each alpha-chain. Arthritis was seen in mice injected with alpha 3(XI) or alpha 1(II). Sera to both alpha-chains reacted similarly with MsII and peptide fragment alpha 1(II)-CB11. Epitope mapping using polyclonal and mAb to type II collagen revealed that all polyclonal and 11 of 14 mAb reacted with alpha 3(XI) and alpha 1(II), whereas three mAb reacted only with alpha 1(II). In conclusion, BXI is immunogenic but not arthritogenic in five strains of mice, whereas alpha 3(XI) and alpha 1(II) are arthritogenic and immunogenic in DBA/1 mice and share greater than or equal to 11 epitopes recognized by autoantibody.

Animals↗
PubMed1991

Transforming growth factor beta 1 (TGF-beta 1) induced neutrophil recruitment to synovial tissues: implications for TGF-beta-driven synovial inflammation and hyperplasia.

We have studied the consequences of introducing human recombinant transforming growth factor beta 1 (hrTGF-beta 1) into synovial tissue of the rat, to begin to better understand the significance of the fact that biologically active TGF-beta is found in human arthritic synovial effusions. Within 4-6 h after the intra-articular injection of 1 microgram of hrTGF-beta 1 into rat knee joints, extensive recruitment of polymorphonuclear leukocytes (PMNs) was observed. Cytochemistry and high resolution histological techniques were used to quantitate the influx of PMNs, which peaked 6 h post-injection. In a Boyden chamber assay, hrTGF-beta 1 at 1-10 fg/ml elicited a chemotactic response from PMNs greater in magnitude than that evoked by FMLP, establishing that TGF-beta 1 is an effective chemotactic agent for PMNs in vitro as well as in vivo. That PMNs may represent an important source of TGF-beta in inflammatory infiltrates was strongly suggested by a demonstration that stored TGF-beta 1 was secreted during phorbol myristate acetate-stimulated degranulation in vitro. Acid/ethanol extracts of human PMNs assayed by ELISA contained an average of 355 ng of TGF/beta 1 per 10(9) cells potentially available for secretion during degranulation of PMNs. [3H]Thymidine incorporation in vivo and autoradiography of tissue sections revealed that widespread cell proliferation was triggered by TGF-beta 1 injection. Synovial lining cells and cells located deep within the subsynovial connective tissue were identified as sources of at least some of the new cells that contribute to TGF-beta 1-induced hyperplasia. Our results demonstrate that TGF-beta is capable of exerting pathogenic effects on synovial tissue and that PMNs may represent a significant source of the TGF-beta present in synovial effusions.

Animals↗
PubMed1990

Adjuvant-induced arthritis in rats. Evidence that autoimmunity to homologous collagens types I, II, IX and XI is not involved in the pathogenesis of arthritis.

We examined the sera of arthritic outbred Wistar and Sprague-Dawley rats and inbred Fisher 344 and Wistar-Lewis rats for autoantibodies to rat type I, II, IX and XI collagens following the induction of arthritis with mycobacteria (MTB). Although many sera collected over an extended time were assayed in addition to acid eluates of arthritic joints, convincing evidence for autoimmunity to collagen could not be demonstrated. Instead, modest non-specific reactions were observed to collagen, irrelevant proteins, and buffer-treated plastic microtitre wells. In contrast, antibodies to purified protein derivative (PPD) were detected in the sera of rats developing adjuvant-induced arthritis, and antibodies to type II collagen, in the sera and joint eluate of rats developing experimental collagen-induced arthritis. Lastly, delayed-type hypersensitivity responses to collagen could not be detected, nor could adjuvant-induced arthritis be attenuated by soluble collagen injected intravenously before challenge with MTB. We conclude that adjuvant-induced arthritis and experimental collagen-induced arthritis are distinct models of rheumatic disease and that autoimmunity to collagen is neither prevalent in adjuvant-induced arthritis nor necessary for its pathogenesis.

Animals↗
PubMed1988

The immune response of guinea-pigs to type II collagen: poor cross-reactivity with homologous type II collagen accounts for resistance to collagen-induced arthritis.

In order to determine the susceptibility of guinea-pigs to collagen-induced arthritis (CIA), Hartley and Strain 13 guinea-pigs were immunized with heterologous or homologous type II collagen. None of the animals developed CIA. Because immunity to type II collagen plays a critical role in CIA, we characterized the guinea-pig's immune response to determine the basis for this resistance. Guinea-pigs develop cellular and humoral reactivity to heterologous type II collagen similar to that of CIA-susceptible rats. The reactions distinguish type I from type II collagen but not among several heterologous type II collagens. The cell-mediated immune (CMI) response was specific for determinants on the primary amino acid structure of collagen, whether native or denatured collagen was used for immunization; however, the humoral response was specific for the form of the molecule used for immunization. Guinea-pigs differ from CIA-susceptible rats in that immunization with homologous or heterologous type II collagen fails to induce significant cross-reactive immunity with the homologous antigen. A transient arthritis could be induced in animals immunized with heterologous type II collagen by injecting them intra-articularly with heterologous but not with homologous type II collagen. Our results show that the disparity between immunity to type II collagen and the susceptibility to develop CIA in guinea-pigs is due to their poor cross-reactive immune response to autologous type II collagen.

Animals↗
PubMed1987

Passive transfer studies with type II collagen antibody in B10.D2/old and new line and C57Bl/6 normal and beige (Chediak-Higashi) strains: evidence of important roles for C5 and multiple inflammatory cell types in the development of erosive arthritis.

C5-normal B10.D2/new line mice were susceptible to passively transferred arthritis from purified type II collagen antibody, and in vitro studies demonstrated that, when bound to cartilage, this antibody readily activated complement C5 to C5a. C5-deficient B10.D2/old line mice failed to develop passively transferred arthritis, despite the deposition of antibody and C3 along the cartilage surface. C57Bl/6 mice were susceptible to passively transferred arthritis, which was characterized in histopathologic studies as an erosive synovitis involving multiple inflammatory cell types. In contrast, neither clinical nor histologic evidence of arthritis was observed in C57Bl/6 mice with the beige mutation (Chediak-Higashi syndrome).

Animals↗
PubMed1986

Assessment of the potential pathogenicity of type II collagen autoantibodies in patients with rheumatoid arthritis. Evidence of restricted IgG3 subclass expression and activation of complement C5 to C5a.

IgG subclass analysis by enzyme-linked immunosorbent assay of the autoantibody to native type II collagen, detected in 9 patients with classic or definite rheumatoid arthritis, demonstrated a predominance of IgG3 autoantibody. Gm allotyping revealed no obvious association with a particular phenotype. In comparative studies, IgG antibodies to the capsular polysaccharides of pneumococci and tetanus toxoid protein in these same patients consisted predominantly of IgG2 and IgG4. Purified type II collagen autoantibody from 3 of these patients activated complement C5 to C5a when bound to human cartilage in vitro, as measured by radioimmunoassay. These results represent direct evidence of a potential pathogenic role for this autoantibody in rheumatoid arthritis.

Animals↗
PubMed1985

Genetic susceptibility to murine collagen II autoimmune arthritis. Proposed relationship to the IgG2 autoantibody subclass response, complement C5, major histocompatibility complex (MHC) and non-MHC loci.

Analysis of the IgG autoantibody subclass response in the collagen II autoimmune arthritis (CII AIA)-susceptible D1 strain mice revealed that the onset of disease was associated with a predominance of IgG2a autoantibody. In a comparative study, resistance in the B6 strain was associated with a deficient IgG2a autoantibody response. B6 IgG1, 2b, and 3 autoantibody responses generally overlapped those of arthritic D1 mice, and estimates of antibody crossreactivity and affinity were similar for both strains. In crosses between D1 and B6, arthritis developed only in those F1 mice with IgG2a autoantibody responses approximating or exceeding those in arthritic D1 mice. Additional studies with B6 and B10 strains suggested an alternate role for the IgG2b autoantibody response. In inbred strains with known genetic backgrounds, a dissociation between the magnitude of the total IgG autoantibody response and the percent of total as IgG2a was demonstrated. The H-2q, Ig-1c D1 strain was a high-total and high-percent IgG2a responder, while the H-2d, Ig-1c D2 strain was a low-total but high-percent IgG2a responder. The H-2b, Ig-1b B6 strain was a low-total and low-percent IgG2a responder, while the H-2b/q, Ig-1b/c (B6D1)F1 hybrid was a low-total but high-percent IgG2a responder. A further dissociation between high-percent IgG2a autoantibody responsiveness and the H-2 haplotype was demonstrated by the H-2 congenic B10.D2/n (H-2d, Ig-1b) strain, in which a low-percent IgG2a response was observed to differ from the D2 strain. High-percent IgG2a autoantibody responsiveness also appeared to be inherited as a dominant trait based upon high responses in all (B6D1)F1 hybrids and backcrosses to D1. These findings suggest that the H-2 haplotype is involved in the total IgG autoantibody response but that the relative fraction of the total response as IgG2a is independent of the H-2 haplotype and possibly related to Igh-C genes. C5-deficient SWR (H-2q, Ig-1c) mice were found to have a high total autoantibody response to mouse CII and IgG2a comparable to arthritic D1 mice, but these mice did not develop arthritis. Based upon these observations, we conclude that susceptibility to CII AIA requires the interaction of multiple genes, both major histocompatibility complex (MHC) and non-MHC, which influence the magnitude (total IgG) and the quality (IgG subclass) of the autoimmune response and the availability of appropriate mediators (C5) to initiate the inflammatory reaction.

Animals↗
PubMed1985

Collagen-induced arthritis in mice. Localization of an arthritogenic determinant to a fragment of the type II collagen molecule.

Purified chick type II collagen was cleaved with cyanogen bromide (CB), and the resulting peptides isolated and renatured. Sera from arthritic DBA/1 mice, immunized with chick type II collagen, were tested for reactivity with each peptide. The sera preferentially recognized peptides 11, 10, and 8, in that order. Some reactivity was also detected to peptides 9, 7, and 12. Because arthritis depends upon binding of antibody to autologous type II collagen in the joint, sera were also tested for reactivity with mouse type II collagen. There was a strong positive correlation between reactivity with peptide 11 and reactivity with mouse collagen, but no correlation was found with any of the other peptides. Peptides 11, 10, and 8 were also used for immunization. Antibodies were detected in response to each of these peptides, but arthritis developed only in mice immunized with peptide 11. We conclude that a major immunogenic and arthritogenic epitope on type II collagen resides in the region of the molecule represented by CB peptide 11.

Animals↗
PubMed1985

Analysis of dimethyl sulfoxide immunosuppression in the rat model of collagen II autoimmune arthritis: an effect dependent upon intraperitoneal administration and associated with toxicity.

The effect of the route of administration of dimethyl sulfoxide on humoral immunity and arthritis was evaluated in the rat model of collagen II autoimmune arthritis. Intraperitoneal administration of 5 g/kg/day (days 0-12) reduced serum anti-collagen II IgG levels, delayed the onset of arthritis, but induced sterile peritonitis in all of the treated animals. The same dose given subcutaneously did not alter humoral or clinical parameters. Lower intraperitoneal doses (0.04 and 0.25 g/kg/day), although non-toxic, were similarly ineffective. Subcutaneous (5 g/kg/day) or topical treatment (both hindpaws dipped twice daily into 70% dimethyl sulfoxide) of established disease (days 16-27) produced a mild anti-inflammatory effect without any immunosuppression. We suggest that the apparent suppression of autoimmunity by dimethyl sulfoxide is dependent upon intraperitoneal administration and a toxic dose of the agent.

Administration, Topical↗
PubMed1985

Physicochemical and immunological studies of the renatured alpha 1(II) chains and isolated cyanogen bromide peptides of type II collagen.

The alpha 1(II) and cyanogen bromide (CB)1-generated peptides of chick type II collagen were isolated, purified, renatured and examined for their physicochemical and immunological properties. The alpha 1(II) chains and peptides CB-6 through CB-12 (3,000 to 40,000 daltons) formed renatured thermostable products as determined by measurements of reduced viscosity, optical rotation and Stokes radius. Moreover, renatured alpha 1 (II) chains and CB-10 were observed to form segment-long-spacing (SLS) crystallites under appropriate conditions. When examined for immunoreactivity with defined rat polyclonal and mouse monoclonal antibodies to chick type II collagen, conformation-dependent epitopes were detected on renatured alpha 1(II) chains and renatured peptides, CB-8, CB-10 and CB-11. Conformation-independent epitopes were also detected on all CB-peptides in their denatured form. These studies demonstrate that the alpha 1 (II) chains and CB-peptides of chick type II collagen can be efficiently renatured and that the renatured products retain some conformation-dependent epitopes present on the naive molecule.

Animals↗
PubMed1984

Collagen autoimmune arthritis.

The evidence is now fairly conclusive that collagen-induced arthritis in rodents is mediated by antitype II collagen autoimmunity. Arthritis is probably initiated by binding of antibodies to the surface of intact articular cartilage. Many of the major manifestations of arthritis, including synovial proliferation, pannus formation, marginal erosion of bone, and destruction of cartilage, can be duplicated by injection of isolated antitype II collagen antibodies. It is not known whether delayed hypersensitivity reactions to collagen can provoke similar lesions in the absence of antibody, but circumstantial evidence suggests they do not. Also clear is that not all anticollagen antibodies are capable of inducing arthritis. The minimal requirements for arthritogenic potential are currently under investigation but probably include the ability to bind native autologous type II collagen. Also IgM antibodies alone are either ineffective or are required in relatively higher concentrations than IgG for induction of arthritis. Autoimmunity to collagen is found in many spontaneous and induced rheumatic diseases other than collagen-induced arthritis. There is at present, however, no direct evidence that this autoimmunity actually contributes to the arthritic process. Nevertheless, the human disease most often associated with collagen autoimmunity is rheumatoid arthritis. In many respects the immune reactions detected in humans with rheumatoid arthritis parallel those of arthritis in rodents. That is, responsiveness is under the control of genes within or linked to the major histocompatibility locus. High responders are limited to only a few haplotypes. Cell-mediated reactions are most vigorous in response to denatured collagen and probably have limited specificity for the type of collagen recognized. Antibodies may be separated into at least two groups, one with broad specificity for denatured collagen and a second highly specific for conformation-dependent determinants on native type II collagen. The latter antibodies are of most interest to researchers because they may be like those that induce arthritis in rodents. There is also ample evidence that antibodies are deposited in the joints of rheumatoid arthritis patients, although the specificity of these antibodies is unknown. Generally, collagen-induced arthritis is a model of antibody-initiated autoimmunity arthritis. Specifically, it is a model of type II collagen autoimmune arthritis. In consideration of its extraarticular manifestations, it may justifiably be referred to as type II collagen autoimmune disease.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗