RESUMO
Oral administration of autoantigens is a safe and convenient way to induce peripheral T-cell tolerance in autoimmune diseases like multiple sclerosis (MS). To increase the efficacy of oral tolerance induction and obviate the need for large-scale purification of human myelin proteins, we use genetically modified lactobacilli expressing myelin antigens. A panel of recombinant lactobacilli was constructed producing myelin proteins and peptides, including human and guinea pig myelin basic protein (MBP) and proteolipid protein peptide 139-151 (PLP(139-151)). In this study we examined whether these Lactobacillus recombinants are able to induce oral and intranasal tolerance in an animal model for multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). Lewis rats received soluble cell extracts of Lactobacillus transformants intranasally three times prior to induction of EAE. For the induction of oral tolerance, rats were fed live transformed lactobacilli for 20 days. Ten days after the first oral administration EAE was induced. Intranasal administration of extracts containing guinea pig MBP (gpMBP) or MBP(72-85) significantly inhibited EAE in Lewis rats. Extracts of control transformants did not reduce EAE. Live lactobacilli expressing guinea pig MBP(72-85) fused to the marker enzyme beta-glucuronidase (beta-gluc) were also able to significantly reduce disease when administered orally. In conclusion, these experiments provide proof of principle that lactobacilli expressing myelin antigens reduce EAE after mucosal (intranasal and oral) administration. This novel method of mucosal tolerance induction by mucosal administration of recombinant lactobacilli expressing relevant autoantigens could find applications in autoimmune disease in general, such as multiple sclerosis, rheumatoid arthritis and uveitis.
Assuntos
Autoantígenos/biossíntese , Encefalomielite Autoimune Experimental/prevenção & controle , Lactobacillus/imunologia , Proteína Básica da Mielina/biossíntese , Administração Intranasal , Administração Oral , Animais , Autoantígenos/genética , Autoantígenos/imunologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Tolerância Imunológica , Immunoblotting , Lactobacillus/genética , Esclerose Múltipla/imunologia , Proteína Básica da Mielina/genética , Proteína Básica da Mielina/imunologia , Ratos , Ratos Endogâmicos LewRESUMO
CD40-CD40 ligand interactions are crucial to cognate interactions between T cells, B cells and antigen-presenting cells (APC), and contribute to non-antigen-specific effector functions of APC in inflammatory disorders. Here we demonstrate that functional blockade of CD40 with an antagonist mouse anti-human CD40 monoclonal antibody (mAb mu5D12) effectively prevents clinical expression of chronic demyelinating experimental autoimmune encephalomyelitis (EAE) in outbred marmoset monkeys, a preclinical model of multiple sclerosis. Anti-CD40 mAb interfered with development of clinical symptoms of marmoset EAE during the treatment period, even when treatment was started several weeks after T cell priming. Magnetic resonance imaging demonstrated inflammatory activity in the brain at initiation of antibody treatment, confirming that treatment interfered with the disease process. Access of therapeutic anti-CD40 to potential sites of action, the secondary lymphoid organs and the brain white matter lesions, was visualized in situ. The present data are the first to demonstrate the clinical potential of blocking APC and effector cell functions using murine antagonist anti-CD40 mAb in the treatment of chronic inflammatory diseases.