The role of apoptosis proteins and complement components in the etiopathogenesis of systemic lupus erythematosus.
Systemic lupus erythematosus is a prototypical autoimmune disease characterized by the deregulation of T and B cells, tissue infiltration by mononuclear cells, tissue damage and the production of autoantibodies. There is a consensus that accelerated apoptosis of circulating lymphocytes and/or impaired clearance of apoptotic bodies may increase the amount of nuclear antigens presented to T lymphocytes. This process is accompanied by autoimmune responses that can lead to the development of lupus. The dysfunction of apoptosis may be a direct consequence of alterations in proteins/genes such as Fas, Bcl-2 and C1q. Increased expression of Fas antigen could intensify the exposure of hidden antigens. The overexpression of Bcl-2 protein might inhibit the removal of auto-reactive cells, and the lack of C1q could impair the clearance of self-antigens. The complete knowledge of the role of apoptosis components in the etiopathogenesis of lupus could lead to the development of new therapies targeting the apoptotic threshold, which could result in a more specific and effective disease response compared to global immunosuppression. This review summarizes the role of each component of the apoptotic process in the pathogenesis of lupus.
Liphaus
Bernadete L
BL
Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo - São Paulo/SP, Brazil. bernadete.liphaus@icr.usp.br
Kiss
Maria Helena Bittencourt
MH
D017209:Apoptosis / Q000276:immunology*; D015922:Complement C1q / Q000172:deficiency / Q000276:immunology*; D053222:Fas Ligand Protein / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000209:etiology* / Q000276:immunology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000276:immunology* / Q000378:metabolism
C505661:FASLG protein, human; D053222:Fas Ligand Protein; D019253:Proto-Oncogene Proteins c-bcl-2; D015922:Complement C1q