Affinity columns containing anti-DNA Id+ human myeloma proteins adsorb human epibodies from intravenous gamma globulin

Treatment options for juvenile-onset systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an inflammatory chronic disease characterized by the presence of activated helper T-cells that induce a B-cell response, resulting in the secretion of pathogenic autoantibodies and the formation of immune complexes. SLE in children is a disease of low prevalence with a wide range of clinical manifestations, which means that the number of randomized controlled studies are few and usually involve a small number of patients. In recent years, new therapeutic agents have appeared and the role of older treatments has been clarified. Many of these treatments are designed to reduce inflammation. The spectrum is broad and ranges from traditional nonsteroidal anti-inflammatory drugs (NSAIDs) to cytotoxic agents that have anti-inflammatory effects. The current treatment of children or adults depends on the clinical expression of the disease. Minor manifestations usually respond to the administration of NSAIDs, low doses of corticosteroids, hydroxychloroquine, or methotrexate. Thalidomide could be used for refractory skin lesions. Major manifestations can endanger the patient's life and require early, aggressive treatment. Kidney disease and other manifestations have been related to the formation or deposit of tissular immune complexes. Therefore, for years the main aim of treatment has been to suppress the immune response. The immunosuppressant treatments used in children with SLE include high doses of corticosteroids, azathioprine, methotrexate, cyclosporine, and cyclophosphamide. Several combinations of medications have been used to obtain a rapid remission or to reduce the risk of toxicity of prolonged administration of cytotoxic agents. Intravenous gamma-globulin has been successfully used in the treatment of lupus nephritis, vasculitis, and acute thrombocytopenia. In spite of numerous published studies, the use of these drugs is still controversial. The immunosuppression achieved with these treatments is nonspecific, not always effective, and associated with significant toxicities; the most significant being growth retardation, accelerated atherosclerosis and severe infectious complications. The purpose of new biological therapies is to achieve specific immunosuppression, which makes it possible to design more effective and less toxic therapeutic strategies. Mycophenolate mofetil is a promising alternative in patients who do not respond to high doses of cyclophosphamide or azathioprine. Some recently developed monoclonal antibodies such as anti-CD40L or anti-IL-10, or other molecules such as LJP394 may prove useful in the near future. Finally, stem cell transplantation may be proposed in patients with severe juvenile-onset SLE who do not respond to any treatment.

Anti-idiotype antibodies abrogate the tissue deposition of anti-RNP human autoantibodies injected into neonatal BALB/c mice

OBJECTIVE

The goals of the current work are: 1) to examine the epidermal deposition of anti-RNP IgG human autoantibodies in neonatal BALB/c mice; 2) to look for immunoregulatory effects of anti-idiotypes allowing one to inhibit the epidermal deposition of anti-RNP antibodies; and 3) to elicit antinuclear antibodies in adult BALB/c mice by internal images of anti-idiotypes.

MATERIALS AND METHODS

Anti-idiotype antibodies were produced with human anti-RNP IgG obtained by ion exchange chromatography; F(ab')2 fragments were recovered from pepsin digestion and were purified using Sephacryl S-300. F(ab')2 fragments were then used to immunize New Zealand rabbits.

RESULTS

The anti-RNP IgG recognized the 70 kDa protein and the A (31 kDa) and C (19 kDa) proteins, while the anti-idiotype antibody specifically recognized the light or heavy chain of the anti-RNP (Fab')2 fragments. Additionally, anti-idiotypes recognized the anti-RNP IgG from some sera, but not the IgG from other specificities or from normal IgG. When anti-RNP IgG was injected intraperitoneally into BALB/c mice it induced immune complex deposition in the epidermis and at the dermal-epidermal junction. Previous injection of anti-idiotype antibodies abrogated the anti-RNP IgG deposits. Vaccination with anti-idiotypes elicit antinuclear antibodies in adult BALB/c mice.

CONCLUSIONS

Anti-idiotype antibodies abrogate in vitro the antinuclear antibody deposition in neonatal BALB/c mice. Anti-idiotype antibodies elicit antinuclear antibodies in adult BALB/c mice.

Monoclonal antibodies and other biologic therapies

The treatment of systemic lupus erythematosus (SLE) presents a significant therapeutic challenge: multi-organ involvement and a variable disease course characterized by clinical exacerbations and remissions make it difficult to predict outcome. Few products have been specifically developed in this clinical indication and most accepted therapies have not been tested in randomized controlled trials in SLE. A variety of biologic agents under investigation as potential treatments for SLE are designed to interfere with specific immunologic responses, hopefully avoiding generalized immunosuppression. These include therapies to downregulate IL-10 and/or upregulate TGFb production. Agents which interfere with T cell activation and T cell-B cell collaboration, such as CTLA4-Ig and anti-CD40 ligand monoclonal antibodies, may result in long term therapeutic benefit; alone or in combination, even following brief treatment courses. Products designed to decrease production of anti-dsDNA antibodies or inhibit complement activation may prevent immune complex deposition and amerliorate organ-specific manifestations such as renal disease. More aggressive interventions include gene therapy and stem cell transplantation. As these agents enter clinical trials, efforts to develop international consensus regarding trial methodology and outcome measures will be crucial to their successful development.

New therapies for systemic lupus erythematosus

New therapies for the treatment of SLE have gained increased attention, as demonstrated by a growing number of new modalities being studied. These modalities include novel biologic agents that target specific immunologic responses and more traditional pharmaceutical agents. This article summarizes these new therapies and briefly discusses their mechanisms of action and the most recent research performed to characterize their safety and efficacy.

Naturally occurring anti-idiotypic antibodies reactive with anti-DNA antibodies in systemic lupus erythematosus

The levels of 'putative' anti-idiotypic antibodies reactive with F(ab')2 fragments of affinity purified DNA binding antibodies from five SLE patients were measured in the serum of active and inactive systemic lupus erythematosus (SLE) patients, their relatives, spouses and healthy non-related individuals. Serum anti-idiotypic antibodies of the IgG isotype could be detected in the serum of 8/15 inactive SLE patients, 3/19 active SLE patients, 17/27 SLE relatives, 1/4 SLE spouses and 6/32 healthy non-related individuals. When the serum immunoglobulins from the individuals in each group were separated into IgG and IgM antibody fractions and analysed, a significant increase in levels of IgG anti-idiotypic reactivity were found in healthy individuals (16/32), whilst no significant increase in IgG anti-idiotypic antibodies were detected in SLE patients, SLE relatives and SLE spouses. Comparatively few individuals tested showed detectable levels of IgM anti-idiotypic antibodies. These results demonstrate that anti-idiotypic antibodies reactive with anti-DNA antibodies are detectable in the serum of SLE patients, SLE relatives, SLE spouses and healthy individuals, and are predominantly of the IgG isotype. The increased frequency of IgG anti-idiotypic antibodies after separation from serum IgM antibodies infers that anti-idiotypic activity of some IgG immunoglobulins in the sera of healthy individuals may be masked by the presence of IgM antibodies in the serum.

Immunotherapy for autoimmune and inflammatory renal diseases

New treatments for autoimmune renal disease are required, and a developing knowledge of its underlying immunopathogenesis has identified sites where immunotherapy is likely to be effective. Experience with intravenous immunoglobulin and lymphocyte depletion by monoclonal antibodies in systemic vasculitis and systemic lupus erythematosus is awaiting confirmation by randomized trials. Treatments at or near clinical testing include monoclonal antibody blockade of leucocyte-endothelial interactions and CD40 mediated B-cell activation, and immunoablation with autologous stem-cell transplantation for more severe multisystem autoimmune disease.