Human HLA-DR beta gene hypervariable region homology in the biobreeding BB rat: selection of the diabetic-resistant subline as a rheumatoid arthritis research tool to characterize the immunopathologic response to human type II collagen.

Collagen arthritis (CA), an autoimmune model of rheumatoid arthritis (RA), has been studied in various animals. However, it has not been studied in an animal with a genetic background relevant to RA. We selected rats from a diabetic-resistant (DR) subline of the diabetic BB rat because they have an autoimmune disease-prone background, but not the immunodeficiencies of the diabetic BB rat, and the third hypervariable region (HVRIII) of the BB RT1.D beta gene appeared to encode a nucleotide sequence of the human HLA DR beta gene, which has been reported to be associated with susceptibility to RA. We synthesized oligonucleotide primers flanking the RT1.D beta HVRIII, cloned polymerase chain reaction-amplified DNA into M13mp18, and confirmed the presence of the susceptibility sequence (SS) (RRRAA) by the dideoxy sequencing method in a colony of DR BB/Wor-UTM rats. When immunized with human type II collagen (CII) in incomplete Freunds adjuvant (IFA), arthritis developed rapidly by day 10 with 100% incidence. Light and electron microscopy revealed an unusually severe and aggressive, bidirectional pattern of cartilage resorption by synovial and subchondral mononuclear and multinucleated inflammatory cells. These findings coincided with a predominant humoral response to the cyanogen bromide (CB) 11 fragment of the human CII molecule by the pathogenic IgG2a isotype. This study provides further support to the role of CA as a relevant RA model, the specific roles of the CB11 fragment as a major site of arthritogenic epitopes, and of antibody mechanisms in the pathogenesis of CA. Furthermore, the identification of an RA SS in an immune response gene of the DR BB rat presents a novel opportunity to determine with an animal model the role of other antigens as well as this SS in RA.

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.

A rapid assay method of collagenase activity using 14C-labeled soluble collagen as substrate.

A rapid assay method for vertebrate collagenase (EC 3.4.24.3) activity has been developed using 14C-labeled soluble collagen as substrate. The method is based on the incubation of collagen with enzyme in the presence of glucose to prevent collagen fibril formation followed by selective extraction of the enzyme digestion products into dioxane at a final concentration of 50%. The rate of reaction was about 10 times higher than that obtained by the conventional method using reconstituted collagen fibrils as substrate and the relationship between enzyme activity and concentration was linear over a wider range. When the method was applied to the assay of human granulocyte collagenase, the results showed good correlation with those obtained by the conventional gel method.

An improved enzyme-linked immunosorbent assay of anti-collagen antibodies in human serum.

An improved enzyme-linked immunosorbent assay (ELISA) for the determination of anti-collagen antibodies in human serum has been developed. The method is based on the use of serum samples diluted to 1/50 with heat-inactivated normal rabbit serum adjusted to pH 8.0 with solid Tris (0.05 M), NaCl (0.15 M) and 2 M HCl. The use of normal rabbit serum minimizes non-specific adsorption of immunoglobulin G onto the plastic surface of microtiter plate. The applicability of the method for the quantitation of anti-collagen antibodies in human serum is demonstrated with 290 specimens of sera from normal controls (194) and patients with rheumatoid arthritis (96).

Monoclonal antibodies against bovine type IX collagen (LMW fragment): production, characterization, and use for immunohistochemical localization studies.

Four high-affinity monoclonal antibodies (MAb) which react specifically with the low molecular weight (LMW) fragment of bovine type IX collagen (BIX) have been produced in mice. On the basis of the ability of these MAb to cross-react with type IX collagen purified from human, rat, and chick cartilage and to inhibit one another in a competitive inhibition assay, we conclude that the MAb D1-9, B3-1, and B2-7 recognize unique epitopes, whereas MAb B4-5 recognizes the same epitope as B3-1. None of the MAb reacted with bovine type I, II, and XI collagen. MAb D1-9 and B3-1 were tested for their ability to bind to tissue antigen, using an immunohistochemical assay system. Positive immunoperoxidase reactions were observed in the perichondrocytic regions of human and rat costochondral cartilage. Positive responses were also detected in rat auricular cartilage, as well as in tissue obtained from the middle and inner ears of rats and mice. This report demonstrates the relative ease of producing MAb to heterologous type IX collagen and the utility of these MAb for localizing type IX collagen in cartilage and cartilage-like tissues.

Type XI and II collagen-induced arthritis in rats: characterization of inbred strains of rats for arthritis-susceptibility and immune-responsiveness to type XI and II collagen.

To determine the relationship between susceptibility to bovine type XI and II (BXI and BII) collagen-induced arthritis, we immunized 14 inbred and one outbred strains of rats with BXI and BII. Susceptibility to BXI-arthritis corresponded largely with susceptibility, or resistance, to BII-arthritis. LEW, BB, WF, DA, and WKY were readily susceptible to BXI- and BII-arthritis. Likewise, BII-resistant F344 and BN rats were BXI-resistant. Some strains responded differently to BXI and BII. BUF and COP, which are moderately susceptible to BII, were BXI-resistant, whereas the BII-resistant rats, DA.1N and WF.1N, were partially susceptible to BXI. (F344 x BN) F1 hybrids responded to both collagens suggesting gene complementation. Arthritis occurred in all strains producing the highest titer antisera (LEW, WF and BB). Antibody responses to BXI and BII were generally commensurate within individual strains. DA were susceptible to arthritis but produced low levels of antibody comparable to BN rats which were arthritis-resistant. BXI and BII-susceptibility was variable in rats producing intermediate antibody responses. Antibodies to RXI were detected in all BXI-immunized rats, whereas antibodies to RV and RII were uniformly weaker. DTH to RXI and RII was strong in both groups of rats, correlating poorly with arthritis and antibody responses. These studies show that phenotypic susceptibility to BXI- and BII-arthritis are largely concordant among inbred rat strains but clear differences exist in certain strains; multiple genes are likely involved.

Collagen-induced arthritis in mice: synergistic effect of E. coli lipopolysaccharide bypasses epitope specificity in the induction of arthritis with monoclonal antibodies to type II collagen.

DBA/1 mice develop a chronic peripheral arthritis after immunization with type II collagen termed collagen-induced arthritis. We have localized the main arthritogenic determinants of CB11, a CNBr-generated arthritogenic fragment of chick type II collagen (CII), using 3 smaller peptide fragments of CB11 generated by endoproteinase LysC, LysC1 (CII 124-290), LysC2 (CII 291-374) and LysC3 (CII 375-402) and a panel of monoclonal antibodies (mAb) specific to CB11. MAb specific to the arthritogenic region of CB11 were also used to study the synergistic effect of E. coli lipopolysaccharide (LPS) on antibody-mediated arthritis in naive DBA/1 mice. LysC2 contained a minimum essential arthritogenic fragment of type II collagen: LysC2 induced arthritis by active immunization, also, a combination of four mAb specific to LysC2 passively transferred arthritis to naive mice. A single i.p. injection of LPS (50 micrograms/mouse) reduced the threshold values of the arthritogenic dose of mAb from 1 mg to 50 micrograms/clone per mouse, and decreased the number of mAb required for inducing arthritis from 4 to 2 clones. These observations suggest that LysC2, an 84 amino acid residue fragment, contains the main arthritogenic determinants within chick CB11. Importantly, LPS, a strong inducer of pro-inflammatory cytokines, negates the required multiple epitope specificity of autoantibodies in the passive transfer model and acts synergistically in the induction of arthritis by autoantibody.

An inhibitory substance of glyceraldehyde 3-phosphate dehydrogenase in urine of diabetic patients.

In urine of diabetics, a significantly great inhibitory activity of glyceraldehyde 3-phosphate dehydrogenase (GAP-Dehyd) was observed compared with that of normal subjects. The 0.2 ml of urine from 41 patients with diabetes mellitus inhibited 0.5 units of GAP-Dehyd by 27.2 +/- 3.0% (mean +/- S.E.M.), while that from 17 normal volunteers inhibited only by 9.0 +/- 1.0% (P less than 0.05). This inhibitory substance was extracted by 90% ethanol from diabetic urine and partially purified by anion exchange chromatography using Dowex-1 (HCOO type). The molecular weight of this substance was confirmed to be 100--300 daltons by an analysis on Biogel P-4 gel filtration chromatography. And analysis by thin layer chromatography using silicagel plate showed that this inhibitor was a ninhydrin reactive substance which has not been reported previously. From the above facts, it was assumed that the inhibitory substance of GAP-Dehyd in urine of diabetics was a new acidic compound of low molecular weight containing an amino residue in the molecule.

Epitope specific antibody response against human type II collagen induced by anti-idiotypic antibody.

A species specific epitope on human type II collagen (CII) recognized with mAb, 2-60, was found to be localized on a cyanogen bromide-cleaved peptide (CB10) of human CII. To characterize the antibody response to the 2-60 epitope, we raised rabbit anti-idiotypic (Id) antibody against 2-60. The rabbit anti-2-60 Id antibody reacted not only with 2-60 mAb but also with 2-56 and 3-11 mAbs which were reactive with the epitopes related to the 2-60 epitope on CB10. The anti-Id antibody inhibited the binding of these three mAbs to human CII. Thus, rabbit anti-2-60 Id antibody recognized the cross-reactive idiotype expressed on 2-60, 2-56 and 3-11. The anti-2-60 Id antibody inhibited about thirty percent of the binding of polyclonal anti-human CII antibody derived from DBA/1J mice, thereby suggesting that the 2-60 idiotype might be expressed on a major fraction of the anti-human CII antibody. Immunization with the rabbit anti-2-60 Id antibody elicited antibody response to the 2-60 epitope, in DBA/1J (H-2q, Ighc), BALB/c (H-2d, Igha) and DBA/2 (H-2d, Ighc) mice. On the other hand, an epitope-specific antibody response induced by rabbit anti-Id antibody to 1-5 mAb reactive with a putative arthritogenic epitope on human CII was shown to be influenced by a single dominant gene, possibly the Igh gene. Our findings suggest that antibody responses against two distinct epitopes on human CII are probably regulated by different mechanisms.

Generation of monoclonal antibodies to the zinc finger domain of the eukaryotic transcription factor Sp1.

Using a synthetic peptide that encompasses the zinc finger domain of the eukaryotic transcription factor Sp1, we produced a number of monoclonal antibodies that specifically reacted with the target antigen. Analysis by competitive inhibition assay of five of the monoclonal antibodies revealed that they all recognized a dominant epitope in the synthetic peptide and reacted strongly to recombinantly synthesized beta-galactosidase-Sp1 fusion polypeptide. To determine cellular distribution of Sp1-like molecules, cytoplasmic and nuclear proteins from human lung fibroblasts (HFL-1) and a human rhabdomyosarcoma cell line (A204) were immunoblotted and reacted with our antibodies. In addition to the well characterized 95 Kd and 105 Kd proteins, considered to be the authentic Sp1 polypeptide, a number of other cellular proteins reacted with these antibodies. Immunofluorescence staining of the cells with mAb to the zinc finger of Sp1 also revealed cell-specific differences in intracellular distribution of Sp1-like molecules. Both cytoplasmic and nuclear staining was readily observed in the rhabdomyosarcoma cells. In contrast, while some HFL-1 cells exhibited staining of only cytoplasm, both cytoplasmic and nuclear immunofluorescence was seen in others.

Plasma and bone osteocalcin levels in rats with type II collagen-induced arthritis.

Osteocalcin levels in plasma and bone were measured by enzyme immunoassay in rats with arthritis induced by immunization with type II collagen and in untreated control rats. Compared with levels in control rats, the plasma levels of osteocalcin in arthritic rats were markedly decreased 1-3 weeks after immunization; during weeks 8-14, these levels were significantly increased. The osteocalcin content of tarsal bones changed in parallel with the plasma levels. These data suggest that osteocalcin levels in the plasma of arthritic rats reflect alterations in bone formation activity.

Establishment of a B-lymphoblastoid cell line infected with Epstein-Barr-related virus from a cynomolgus monkey (Macaca fascicularis).

A B-lymphoblastoid cell line (Ts-B) was established from lymph nodes of an apparently healthy cynomolgus monkey. The cells were demonstrated to contain Epstein-Barr virus-related antigens. Moreover, herpesvirus particles were found in the cells by electron microscopy. The cell-free culture medium transformed lymphocytes of cynomolgus rhesus monkeys, and of Japanese monkeys.

Characterization of a tolerogenic T cell epitope of type II collagen and its relevance to collagen-induced arthritis.

A synthetic peptide representing sequences of type II collagen, (CII 245-270), has previously been used to induce tolerance and suppress arthritis in DBA/1 mice. To determine important residues, a series of peptides, each containing one or two site-directed substitutions, was generated. Mononuclear cells from DBA/1 mice immunized with CII were cultured in the presence of each peptide and the T cell response determined by measuring IFN-gamma in culture supernatant fluids. Substitutions within the region CII 260-270 led to significant decreases in IFN-gamma responses, identifying this sequence as a T cell epitope. To determine the effects of substitutions within this epitope on arthritis, substituted peptides were administered to neonatal mice as tolerogens. Five site-directed substitutions, four of which included the insertion of a residue found in type I collagen to replace its type II counterpart, abrogated the ability of the peptides to induce tolerance and suppress arthritis. These substitutions were located at residues 260, 261, 263, 264, and 266. Two patterns of T cell reactivity were observed. Peptides containing individual substitutions at positions 261, 264, or 266 were capable of generating a significant T lymphokine response, although those containing substitutions at residues 260 or 263 were ineffective Ag. Systematic analysis of the fine structures of T cell determinants important for autoimmune arthritis can lead to strategies for therapeutic intervention.

In vitro effect of N-methoxy-3-(3,5-ditert-butyl-4-hydroxybenzylidene)-2-pyrrolidon e (E-5110), a novel nonsteroidal antiinflammatory agent, on generation of some inflammatory mediators.

Cultured rat synovial cells generate PGE2 upon stimulation with a factor derived from rate polymorphonuclear cells (Prostaglandins 27, 697, 1984). E-5110 inhibited PGE2 generation by the synovial cells. The IC50 values (microM) for inhibition of PGE2 generation were 0.026 for E-5110, 0.008 for indomethacin, 0.112 for piroxicam, 0.003 for R-830, 0.667 for BW-755C and 2.05 for benoxaprofen. Calcium ionophore A-23187-stimulated LTB4 generation by human neutrophils was inhibited by E-5110 with an IC50 value of 0.20 microM, which was similar to NDGA. The inhibition of LTB4 by E-5110 was more potent than that of R-830, BW-755C or benoxaprofen. E-5110 also inhibited superoxide generation by human neutrophils stimulated with opsonized zymosan, f-Met-Leu-Phe and phorbol myristate acetate. These results indicate that E-5110 is a potent dual inhibitor that suppresses superoxide generation.

Analysis of type II collagen reactive T cells in the mouse. II. Different localization of immunodominant T cell epitopes on heterologous and autologous type II collagen.

The specificity of the recognition of type II collagen (CII) by T cells in the DBA/l mouse was analysed using fragments of chick and rat CII obtained by cyanogen bromide (CB) cleavage. Firstly, DBA/l mice were immunized with chick CB fragments 5, 8, 9, 10, 11 and 12. Ten days later the draining lymph node cells were cultured with rat and mouse CII and the proliferative response was determined by incorporation of [3H]thymidine. All peptides were capable of triggering T cells recognizing rat CII but only CB9 immunized mice responded well to mouse CII. Secondly, lymph node cells from DBA/l mice immunized with rat and mouse CII were cultured with the CB fragments, including rat CB10 and CB11, and the proliferative response was determined. After immunization with rat CII, the response was strongly dominated by T cells recognizing CB11 with equal responses against chick and rat CB11. After immunization with mouse CII only rat CB10 gave a strong response. It is concluded that several epitopes on the CII molecule can be recognized by T cells in the DBA/l mouse and that most of these epitopes are shared by rat and chick CII but not mouse CII. These epitopes exhibit strong immunodominance. In mice immunized with intact heterologous CII, the immunodominant response is directed against one or more epitopes on the CB11 fragment present on several heterologous CII but apparently not on mouse CII. In mice immunized with autologous CII the immunodominant response is directed against one or more epitopes on the CB10 fragment, present on rat and mouse CII. They are either absent in chick CII or located in the carboxyterminal end of the CB10 fragment where a cyanogen bromide cleavage site is present in chick CII but not in rat CII. These results suggest that the proposed importance of CB11 in collagen-induced arthritis is due to activation of T cells reactive with heterologous CII only. These cells may be important for the induction of the strong auto-antibody-response after immunization with heterologous CII. Structures of importance for direct T cell involvement in the arthritic process and recognized by autoreactive T cells are suggested to be found on CB10.

Suppression of type II collagen-induced arthritis by monoclonal antibodies.

Some mouse monoclonal antibodies raised against chicken type II collagen suppressed or delayed the onset of chicken type II collagen-induced arthritis in DBA/1 mice. This was correlated with the suppression of anti-mouse type II collagen antibody responses following immunization with chicken type II collagen. The epitopes recognized by the suppressive antibodies were found to be present on cyanogen bromide (CB)-digested collagen peptides CB-11 and CB-12. This was also confirmed by the finding that administration of the CB-11 or CB-12 peptide suppressed the induction of arthritis.

Autoreactivity against matrilin-1 in a patient with relapsing polychondritis.

Relapsing polychondritis (RP) is a rare inflammatory disease of cartilage. Chondritis of the auricular, nasal, and tracheal cartilages predominates in this disease, suggesting a response to a tissue-specific antigen. One potential antigen is matrilin-1, a cartilage matrix protein found uniquely in the tracheal, auricular, and nasal cartilage of adults. We describe herein a patient with RP who had both a humoral and a cellular immune response directed toward the cartilage matrix protein matrilin-1.