Treatment of collagen-induced arthritis with an anti-osteopontin monoclonal antibody through promotion of apoptosis of both murine and human activated T cells

OBJECTIVE: To test the effects of a novel monoclonal antibody (mAb) against human osteopontin (OPN) in the prevention and treatment of collagen-induced arthritis (CIA) and to elucidate the underlying mechanisms of these effects. METHODS: DBA/1J mice immunized with type II collagen to induce CIA were monitored to assess the effects of anti-OPN mAb on the clinical severity of the disease, and pathologic changes in the joints were examined histologically. The effects of anti-OPN mAb on survival of activated T cells from arthritic mice and from the synovial fluid of patients with rheumatoid arthritis (RA) were determined by TUNEL assay or annexin V assay. The levels of apoptosis-related proteins (Bim, Bax, and Bcl-2) and NF-kappaB were detected by immunoblot analysis. RESULTS: One anti-OPN mAb, 23C3, was effective in inhibiting the development of CIA and even reversing established disease in DBA/1J mice. Monoclonal antibody 23C3 reduced the levels of serum type II collagen-specific autoantibodies and proinflammatory cytokines, and suppressed T cell recall responses to type II collagen. Mechanistic studies demonstrated that OPN prevented the death of type II collagen-activated murine T cells and synovial T cells from RA patients. Monoclonal antibody 23C3 promoted apoptosis of the activated T cells, particularly CD4+ T cells, by inhibiting activation of NF-kappaB and by altering the balance among the proapoptotic proteins Bim and Bax and the antiapoptotic protein Bcl-2. Screening of a phage display peptide library led to identification of the epitope ATWLNPDPSQKQ as being recognized by this novel antibody. CONCLUSION: Because of its ability to effectively promote apoptosis of activated T cells, mAb 23C3 may be a novel therapeutic agent for the treatment of RA.     

Treatment with a neutralizing anti‐murine interleukin‐17 antibody after the onset of collagen‐induced arthritis reduces joint inflammation,cartilage destruction,and bone erosion

Objective

Interleukin‐17 (IL‐17) is a proinflammatory cytokine that is expressed in the synovium of rheumatoid arthritis (RA) patients. This T cell cytokine is implicated in the initiation phase of arthritis. However, the role of IL‐17 during the effector phase of arthritis has still not been identified; this was the objective of the present study.

Methods

Mice with collagen‐induced arthritis (CIA) were treated with polyclonal rabbit anti‐murine IL‐17 (anti–IL‐17) antibody–positive serum or normal rabbit serum after the first signs of arthritis. In addition, during a later stage of CIA mice were selected and treated with anti–IL‐17 antibody or control serum. Arthritis was monitored visually, and joint pathology was examined radiologically and histologically. Systemic IL‐6 levels were measured by enzyme‐linked immunosorbent assay, and local synovial IL‐1 and receptor activator of NF‐κB ligand (RANKL) expression was analyzed using specific immunohistochemistry.

Results

Treatment with a neutralizing anti–IL‐17 antibody after the onset of CIA significantly reduced the severity of CIA. Radiographic analysis revealed marked suppression of joint damage in the knee and ankle joints. Histologic analysis confirmed the suppression of joint inflammation and showed prevention of cartilage and bone destruction after anti–IL‐17 antibody therapy. Systemic IL‐6 levels were significantly reduced after anti–IL‐17 antibody treatment. Moreover, fewer IL‐1β–positive and RANKL‐positive cells were detected in the synovium after treatment with neutralizing IL‐17. Interestingly, initiation of anti–IL‐17 antibody therapy during a later stage of CIA, using mice with higher clinical arthritis scores, still significantly slowed the progression of the disease.

Conclusion

IL‐17 plays a role in early stages of arthritis, but also later during disease progression. Systemic IL‐6 was reduced and fewer synovial IL‐1–positive and RANKL‐positive cells were detected after neutralizing endogenous IL‐17 treatment, suggesting both IL‐1–dependent and IL‐1–independent mechanisms of action. Our data strongly indicate that IL‐17 neutralization could provide an additional therapeutic strategy for RA, particularly in situations in which elevated IL‐17 may attenuate the response to anti–tumor necrosis factor/anti–IL‐1 therapy.

     

A tumor necrosis factor receptor loop peptide mimic inhibits bone destruction to the same extent as anti–tumor necrosis factor monoclonal antibody in murine collagen‐induced arthritis

Objective

The cyclic peptide WP9QY (YCWSQYLCY) was designed to mimic the most critical tumor necrosis factor α (TNFα) recognition loop on TNF receptor I, and it prevents interactions of TNFα with its receptor. We undertook this study to compare the effects of the WP9QY peptide on collagen‐induced arthritis (CIA) in mice with those of anti‐TNFα monoclonal antibody.

Methods

CIA was induced by primary and secondary immunizations. Osmotic minipumps were implanted in the backs of all mice on the day of the booster injection (day 21), and vehicle, anti‐TNF antibody (4 mg/kg/day), or WP9QY peptide (2 mg/kg/day or 4 mg/kg/day) was continuously infused until the mice were killed (day 40). Thereafter, clinical, radiographic, and histologic assessments were performed.

Results

WP9QY treatment inhibited CIA‐induced increases in the arthritis score, but onset of disease was not delayed by the peptide. The inhibitory effect of WP9QY on inflammation was definitely weaker than that of anti‐TNF antibody. Microfocal computed tomography analyses, however, revealed that WP9QY blocked CIA‐induced bone destruction at the knee joints to the same extent as did anti‐TNF antibody. In addition, WP9QY inhibited synovial pannus infiltration and reduced osteoclast number. Furthermore, inhibition of CIA‐induced systemic bone loss by WP9QY was more apparent than that by anti‐TNF antibody.

Conclusion

The TNFα antagonist WP9QY would be a useful template for the development of small molecular inhibitors to prevent both inflammatory bone destruction and systemic bone loss in rheumatoid arthritis.

     

Treatment of murine collagen‐induced arthritis by ex vivo extracellular superoxide dismutase gene transfer

Objective

Superoxide dismutase (SOD) is a potent antiinflammatory enzyme that has received growing attention for its therapeutic potential. This study was undertaken to examine the efficacy of extracellular SOD (EC‐SOD) gene therapy in murine collagen‐induced arthritis.

Methods

Embryonic DBA/1 mouse fibroblasts were infected with a recombinant retrovirus expressing human EC‐SOD. DBA/1 mice that had been treated with type II collagen were administered subcutaneous injections of 2 × 10⁷ EC‐SOD–expressing fibroblasts on day 29, when symptoms of arthritis were already present. The severity of arthritis in individual mice was evaluated in a double‐blind manner; each paw was assigned a separate clinical score, and hind paw thickness was measured with a caliper. Mice were killed on day 50 for histologic examination of the joints.

Results

High serum concentrations of EC‐SOD were maintained for at least 7 days. Mice treated with the transgene exhibited significant suppression of clinical symptoms such as disabling joint swelling, deformity, and hind paw thickness, compared with the untreated group (mean ± SD maximum clinical score in the untreated and the transgene‐treated groups 2.71 ± 1.08 and 1.35 ± 1.22, respectively; P < 0.01, and hind paw thickness 3.04 ± 0.18 mm and 2.56 ± 0.12 mm, respectively; P < 0.05). Histologic abnormalities, including destruction of cartilage and bone, infiltration of mononuclear cells, and proliferation of synovial cells, were also markedly improved in the EC‐SOD–treated mice compared with the control group (histopathologic score 7.50 ± 1.13 and 4.13 ± 1.88 in the untreated and transgene‐treated groups, respectively; P < 0.05).

Conclusion

These results indicate that EC‐SOD gene transfer may be an effective form of therapy for rheumatoid arthritis.

     

Expression of osteopontin at sites of bone erosion in a murine experimental arthritis model of collagen‐induced arthritis: Possible involvement of osteopontin in bone destruction in arthritis

Objective

To investigate the involvement of osteopontin (OPN) in bone destruction in a murine experimental arthritis model of collagen‐induced arthritis (CIA).

Methods

The expression of OPN was examined at both the messenger RNA (mRNA) and protein levels in various arthritic lesions in mice with CIA by in situ hybridization and immunohistochemistry, respectively. In addition, the expression of αvβ3 integrin, a receptor for OPN, the ligation of which is thought to be essential for bone resorption by osteoclasts, was examined by immunohistochemistry. Plasma concentrations of OPN were measured at different time points in the course of CIA by enzyme‐linked immunosorbent assay.

Results

OPN mRNA was detected mainly at sites of bone erosion in arthritic lesions, where activated osteoclasts were present; OPN protein was also detected at sites of bone erosion. In the arthritic synovium, OPN was predominantly expressed in the synovial lining layer, but not in lymphoid aggregates. In addition, αvβ3 integrin was detected coincident with OPN at sites of bone erosion (bone–pannus junction). Plasma OPN levels were markedly elevated at the time points that corresponded to arthritis flares, and higher levels were maintained during the progression of arthritis.

Conclusion

OPN may mediate bone resorption by osteoclasts in arthritis through ligation with its receptor, αvβ3 integrin. OPN may be a useful therapeutic target molecule in the prevention of bone destruction in arthritis.

     

Characterization of the antibody response in mice with type II collagen–induced arthritis,using monoclonal anti–type II collagen antibodies

Twenty monoclonal antibodies reactive with type II collagen were characterized as to their determinant specificity and their reactivity with cartilage-derived components. The monoclonal antibodies reacted with 7 different epitopes on the native type II collagen triple helical structure. Antibodies defining 3 of these epitopes occurred more frequently in sera from arthritic mice than in sera from nonarthritic mice. In vivo injection of some selected autoreactive antibodies caused synovitis, but in no case did it give rise to full-blown arthritis.     

Mechanisms of effects of complement inhibition in murine collagen‐induced arthritis

Objective

To determine the mechanisms of amelioration of collagen‐induced arthritis (CIA) in DBA/1J mice by inhibition of complement activation.

Methods

Mice received 2 intradermal injections of bovine type II collagen (CII), on days 0 and 21. From day 21 (immediately after the second injection of CII) through day 35, mice received intraperitoneal injections of either phosphate buffered saline (PBS), a monoclonal mouse antibody to murine C5 (anti‐C5 antibody), or the C3 convertase inhibitor Crry‐Ig.

Results

On days 30 and 32, the clinical disease activity score was lower in mice treated with anti‐C5 antibody than in those treated with Crry‐Ig. Histopathologic evidence of joint damage was 75% lower in the mice treated with anti‐C5 antibody than in those treated with either PBS or Crry‐Ig. Spleen cells from mice receiving either form of complement inhibition exhibited decreased CII‐stimulated proliferation, whereas increased proliferative responses were exhibited by lymph node cells from mice treated with Crry‐Ig. Treatment with anti‐C5 antibody decreased production of IgG1 anticollagen antibody, while production of IgG2a antibody was inhibited by both complement inhibitory treatments. CII‐stimulated spleen cells from anti‐C5–treated mice produced lower levels of tumor necrosis factor α (TNFα) and interleukin‐10 (IL‐10) compared with those from mice treated with Crry‐Ig. Lower steady‐state messenger RNA (mRNA) levels for TNFα, interferon‐γ (IFNγ), IL‐18, and IL‐6 were observed in the joints of anti‐C5–treated mice, and for IFNγ and IL‐6 in mice receiving Crry‐Ig, all in comparison with PBS‐treated mice. However, mRNA levels for IL‐1β and TNFα were lower in the joints after treatment with anti‐C5 compared with Crry‐Ig.

Conclusion

These results indicate that inhibition of complement in CIA leads to decreased production of IgG2a antibody and suppressed CII‐induced spleen cell proliferation. The greater inhibitory effects on CIA of anti‐C5 antibody in comparison with Crry‐Ig may be attributable primarily to decreased levels of IL‐1β and TNFα mRNA in the joints.

     

Immunogenicity of recombinant type IX collagen in murine collagen‐induced arthritis

Objective

Past attempts to isolate type IX collagen (CIX) from cartilage using limited proteolysis yielded partially degraded material. Recent application of recombinant technology, however, has allowed the preparation of intact native CIX. We used the murine collagen‐induced arthritis model to characterize the immunologic properties of recombinant human CIX (rCIX) produced using a baculovirus expression system.

Methods

A panel of B10 congenic mice was immunized with rCIX emulsified with Freund's complete adjuvant (CFA). The ability of the rCIX to induce tolerance and suppress arthritis was determined by administration intravenously or orally before challenge with CII/CFA.

Results

None of the mice immunized with rCIX developed overt arthritis, although 2 of 5 HLA–DR1 transgenic mice developed limited digital erythema and swelling. Recombinant CIX administered by either route effectively induced suppression of arthritis, although the suppression was less pronounced than that induced with CII. Immune responses to CIX and CII were specific, suggesting that bystander suppression, rather than cross‐reactivity with CII, was instrumental in suppressing arthritis.

Conclusion

These data show that CIX down‐regulates arthritis in mice while having no associated risk of inducing arthritis.

     

Plasmid encoding interleukin‐4 in the amelioration of murine collagen‐induced arthritis

Objective

To evaluate the therapeutic effect of the administration of plasmid encoding interleukin‐4 (IL‐4) via gene‐gun delivery and via intradermal injection on collagen‐induced arthritis (CIA).

Methods

IL‐4 plasmid was administered by gene‐gun delivery and intradermal injection to DBA/1 mice immunized with type II collagen (CII). The therapeutic effect on the development of CIA was evaluated clinically with a visual scoring method for arthritis and serologically by enzyme‐linked immunosorbent assays and polymerase chain reaction.

Results

Treatment with IL‐4–expressing plasmid significantly reduced the incidence and severity of CIA, including a reduction in the anti‐CII antibody level. In particular, gene‐gun delivery had a higher immunosuppressive effect on CIA compared with intradermal injection. As shown by in vitro stimulation assay, the spleen cells from mice immunized with CII and treated with IL‐4 plasmid via gene gun exhibited higher Th2 cytokine responses compared with cells treated with control plasmid after in vitro stimulation with CII.

Conclusion

The results of this study suggest that treatment with IL‐4 plasmid may constitute a new clinical use of cytokine gene therapy for rheumatoid arthritis.

     

Treatment of refractory fludarabine induced autoimmune haemolytic with the anti‐cd20 monoclonal antibody rituximab

A patient with cold‐type autoimmune haemolytic anaemia for 8 years developed progressive B cell chronic lymphocytic leukaemia (CLL). Despite the risk of fludarabine induced exacerbation of haemolysis, he was given aggressive anti‐CLL therapy with six courses of FCR (fludarabine 25 mg/m² D1–3, cyclophosphamide 250 mg/m² D2–4 and rituximab 375 mg/m² D1) every 4 weeks. This resulted in a marked acute increase in haemolysis shortly after completing each course of fludarabine. However, haemolysis had settled to its baseline level by the time of subsequent courses of FCR. FCR resulted in complete clinical remission of CLL but residual haemolysis persisted. The patient was then given four weekly infusions of single agent rituximab, resulting in ongoing remission of haemolysis. In this patient, rituximab appears to have controlled fludarabine induced exacerbation of autoimmune haemolysis. In addition, subsequent single agent rituximab therapy resulted in prolonged remission of cold‐type autioimmune haemolytic anaemia. It remains to be seen if the addition of rituximab will allow other patients with a positive direct Coomb's test and/or autoimmune haemolysis to receive fludarabine containing chemotherapy without undue risk of life‐threatening haemolytic anaemia.     

Treatment of murine collagen‐induced arthritis by the stress protein BiP via interleukin‐4–producing regulatory T cells: A novel function for an ancient protein

Objective

Following the demonstration that the stress protein, BiP, prevented induction of collagen‐induced arthritis (CIA) in HLA–DRB*0101^+/+ (HLA–DR1^+/+) mice, we investigated the immunotherapeutic ability of BiP to suppress disease during the active phase of CIA in HLA–DR1^+/+ and DBA/1 mice.

Methods

BiP was administered either subcutaneously or intravenously to DBA/1, HLA–DR1^+/+, or interleukin‐4 (IL‐4)–knockout mice at the onset of arthritis. Immune cells were used in adoptive transfer studies or were restimulated in culture with BiP or type II collagen (CII). Proliferation and cytokine release were measured. In addition, serum anti‐CII antibodies were measured by enzyme‐linked immunosorbent assay. Disease progression was scored using a visual analog scale.

Results

BiP was successful in suppressing established CIA in HLA–DR1^+/+ and DBA/1 mice. Serum levels of anticollagen IgG antibodies were reduced in BiP‐treated mice. T cells from BiP‐immunized mice produced Th2 cytokines, in particular, IL‐4. Treatment with BiP was also shown to increase the production of CII‐specific IL‐5, IL‐10, and interferon‐γ at the termination of the study. Development of severe CIA was prevented by the intravenous transfer of BiP‐specific cells at the time of CIA induction in HLA–DR1^+/+ mice or by transferring BiP‐specific cells to DBA/1 mice at the onset of disease. BiP failed to ameliorate the development of CIA in IL‐4^−/−, HLA–DR1^+/+ mice.

Conclusion

These novel results show that BiP can suppress active CIA by the induction of regulatory cells that act predominantly via IL‐4. Thus, BiP is a potential immunotherapeutic agent for the treatment of patients with rheumatoid arthritis.

     

Assessment of the efficacy of different statins in murine collagen‐induced arthritis

Objective

Hydroxymethylglutaryl‐coenzyme A reductase inhibitors (statins) are widely used lipid‐lowering agents. In addition to their well‐known effect on cholesterol levels, statins have been reported to display antiinflammatory activities both in vitro and in vivo. In this context, in vivo prophylactic and therapeutic effects of simvastatin were recently demonstrated in mouse collagen‐induced arthritis, a well‐described experimental model for human rheumatoid arthritis (RA). The aim of this study was to further investigate in vivo effects of 3 different statins, atorvastatin, rosuvastatin, and simvastatin, using the same experimental model.

Methods

Different doses and routes of administration were used for the various statins in an attempt to elicit antiarthritic activity in preventive and curative treatment protocols.

Results

Atorvastatin and rosuvastatin had no in vivo efficacy, as indicated by clinical, histologic (synovial hyperplasia, exudate, and cartilage damage), immunologic (anti–type II collagen IgG production), and biochemical (interleukin‐6, serum amyloid A, and glucocorticoid production) parameters of inflammation and autoimmunity. The previously described beneficial effects of administration of intraperitoneal simvastatin were reproduced in our experiments, but could be accounted for by very severe side effects of the treatment, leading to increased glucocorticoid levels.

Conclusion

This work shows that different statins have no effect in a murine model of arthritis, an unexpected observation given the previously described therapeutic effect of statins in immune‐mediated inflammatory diseases. It is still unclear whether statins will have benefit in the treatment of RA.

     

Liver X receptor agonism promotes articular inflammation in murine collagen‐induced arthritis

Objective

Liver X receptors (LXRs) have previously been implicated in the regulation of inflammation and have, in general, been ascribed an antiinflammatory role. This study was therefore undertaken to explore the biologic mechanisms of LXRs in vivo and in vitro in an experimental inflammatory arthritis model.

Methods

Male DBA/1 mice were immunized with type II collagen and treated from an early or established stage of arthritis with 2 different concentrations of the LXR agonists T1317 and GW3965 or vehicle control. The mice were monitored for articular inflammation and cartilage degradation by scoring for clinical signs of arthritis, histologic examination of the joints, and analysis of serum cytokine and antibody levels. In vitro, primary human monocytes and T cells were cultured in the presence of GW3965 or T1317, and the concentrations of proinflammatory cytokines were measured by multiplex assay.

Results

Contrary to expectations, LXR agonism with the use of 2 discrete, specific molecular entities led to substantial exacerbation of articular inflammation and cartilage destruction in this murine collagen‐induced arthritis model. This was associated ex vivo with elevated cytokine expression, with enhanced Th1 and Th17 cellular responses, and with elevated collagen‐specific autoantibody production. In vitro, LXR agonists, in concert with lipopolysaccharide, promoted cytokine and chemokine release from human monocytes, and similar effects were observed in a T cell–macrophage coculture model that closely recapitulates the pathways that drive synovial cytokine release.

Conclusion

Since LXRs are present in rheumatoid arthritis (RA) synovium, these results suggest that LXR‐mediated pathways could exacerbate the chronic inflammatory response typical of RA.

     

A comparative genetic analysis between collagen‐induced arthritis and pristane‐induced arthritis

Objective

To compare the genetic regulation of collagen‐induced arthritis (CIA) with that of pristane‐induced arthritis (PIA) in rats.

Methods

A genome‐wide linkage analysis of an (E3 × DA)DA backcross of rats with CIA (n = 364 male rats; the same strain combinations as previously used to determine the genetic control of PIA) was performed. The strongest loci in both CIA and PIA (i.e., Cia12/Pia4 and Cia13/Pia7) were isolated in congenic strains. Susceptibility in both congenic strains was tested in rats with CIA and in rats with PIA.

Results

We found a striking, although not complete, similarity of the arthritis‐controlling loci in CIA and in PIA, as well as the previously defined loci associated with cartilage destruction, antibody production, and the acute‐phase response. All major PIA quantitative trait loci (QTLs) identified in early severe arthritis were also strong regulators of CIA. The 2 strongest QTLs, Cia12/Pia4 on chromosome 12 and Cia13/Pia7 on chromosome 4, were also analyzed in congenic strains with DA or E3 as the background genome. Consistent with the results of linkage analysis, the congenic strain experiments showed that the chromosome 4 locus was more penetrant in CIA than in PIA, while the chromosome 12 locus almost completely dominated the control of PIA severity.

Conclusion

The underlying genetic control of CIA was found to have many, but not all, pathogenic mechanisms in common with PIA, despite the use of a cartilage‐specific antigen (type II collagen) to induce CIA but not PIA.

     

Prostaglandin D2 regulates joint inflammation and destruction in murine collagen‐induced arthritis

Objective

Prostaglandin D₂ (PGD₂) may exert proinflammatory or antiinflammatory effects in different biologic systems. Although this prostanoid and the enzymes responsible for its synthesis are up‐regulated by interleukin‐1β (IL‐1β) in human chondrocytes in vitro, the role of PGD₂ in arthritis remains unclear. This study was undertaken to investigate the role of PGD₂ in the inflammatory response and in joint destruction during the development of collagen‐induced arthritis (CIA) in mice.

Methods

PGD₂ and cytokine levels in mice with CIA were determined by enzyme‐linked immunosorbent assay. Expression of hematopoietic PGD synthase (h‐PGDS), lipocalin‐type PGD synthase (l‐PGDS), and DP1 and DP2 receptors was analyzed by immunohistochemical methods. PGE₂ levels were determined by radioimmunoassay.

Results

The arthritic process up‐regulated the expression of h‐PGDS, l‐PGDS, DP1, and DP2 in articular tissue. PGD₂ was produced in the joint during the early phase of arthritis, and serum PGD₂ levels increased progressively throughout the arthritic process, reaching a maximum during the late stages of CIA. Treatment of arthritic mice with the DP1 antagonist MK0524 soon after the onset of disease increased the incidence and severity of CIA as well as the local levels of IL‐1β, CXCL‐1, and PGE₂, whereas IL‐10 levels were reduced. The administration of the DP2 antagonist CAY10595 did not modify the severity of arthritis. The injection of PGD₂ into the paw, as well as the administration of the DP1 agonist BW245C, significantly lowered the incidence of CIA, the inflammatory response, and joint damage.

Conclusion

Our findings indicate that PGD₂ is produced in articular tissue during the development of CIA and plays an antiinflammatory role, acting through the DP1 receptor.

     

Long‐term amelioration of established collagen‐induced arthritis achieved with short‐term therapy combining anti‐CD3 and anti–tumor necrosis factor treatments

Objective

The goal of rheumatoid arthritis (RA) treatment is to achieve clinical remission in order to limit structural damage and physical disability. To this end, recent emphasis has been placed on aggressive treatment early in the course of disease with drugs such as anti–tumor necrosis factor (anti‐TNF) agents. As T cells are also thought to play an important role in the initiation of RA, we hypothesized that targeting both TNF and T cells would result in better outcomes. The aim of this study was to examine the efficacy of combined therapy with anti‐CD3 and anti‐TNF in experimental RA.

Methods

Two anti‐mouse antibodies were developed as surrogate reagents for anti‐TNF and anti‐CD3 therapies. Collagen‐induced arthritis (CIA) was induced in DBA/1 mice, and antibodies were injected intraperitoneally, either alone on in combination, at predetermined subtherapeutic doses. The frequency and number of pathogenic and regulatory CD4+ T cell subsets in the draining lymph nodes were determined in order to investigate the mechanisms of action.

Results

Strikingly, the combination of the two antibodies demonstrated a potent synergy in established CIA, with long‐term inhibition of disease progression and protection from joint destruction. The results did not demonstrate any enhancement of CD25+FoxP3+ regulatory T cells, but a profound depletion of pathogenic T cells from the draining lymph nodes was associated with reduced numbers of T cells in the joints.

Conclusion

A short course of combination therapy with anti‐CD3 and anti‐TNF efficiently depletes pathogenic T cells from the draining lymph nodes, reducing the numbers of T cells in the joints and affording long‐lasting inhibition of established CIA.

     

Effective treatment of collagen‐induced arthritis by adoptive transfer of CD25+ regulatory T cells

Objective

Regulatory T cells play an important role in the prevention of autoimmunity and have been shown to be effective in the treatment of experimental colitis, a T cell–mediated and organ‐specific disease. We previously demonstrated that intrinsic CD25+ regulatory T cells modulate the severity of collagen‐induced arthritis (CIA), which, in contrast to colitis, is a systemic antibody‐mediated disease and an accepted model of rheumatoid arthritis. We undertook this study to determine whether regulatory T cells have the potential to be used therapeutically in arthritis.

Methods

We transferred CD4+,CD25+ T cells into mice exhibiting arthritis symptoms, both immunocompetent mice and mice subjected to lethal irradiation and rescued with syngeneic bone marrow transplantation.

Results

A single transfer of regulatory T cells markedly slowed disease progression, which could not be attributed to losses of systemic type II collagen–specific T and B cell responses, since these remained unchanged after adoptive transfer. However, regulatory T cells could be found in the inflamed synovium soon after transfer, indicating that regulation may occur locally in the joint.

Conclusion

Our data indicate that CD25+ regulatory T cells can be used for the treatment of systemic, antibody‐mediated autoimmune diseases, such as CIA.