title: Complement receptor 2 and autoimmunity.
abstract: Complement receptor 2 (CR2/CD21) plays a major role in the immune response by linking innate and adaptive immunity to foreign pathogens and proteins. In addition, several lines of evidence strongly support a role for CR2 in the maintenance of tolerance to self-antigens. Both the absence of CR2 expression (along with the alternatively spliced gene product CR1) and the presence of a dysfunctional CR2 protein are tightly associated with the development of autoreactivity to nuclear antigens. Altered levels of expression of CR2 in patients with systemic lupus erythematosus support a clinically relevant role for this phenotype. Several possible mechanisms could underlie the loss of self-tolerance related to CR2, but the effect is most likely related to the failure of one or more specific checkpoints that limit autoreactivity during B cell development and immune reactions.
authors.affiliation: Departments of Medicine and Immunology, University of Colorado Health Sciences Center, Denver, Colo., USA. Michael.Holers@UCHSC.edu
authors.forename: V Michael
authors.initials: VM
authors.lastname: Holers
authors.forename: Susan A
authors.initials: SA
authors.lastname: Boackle
mesh_terms: D000818:Animals; D015551:Autoimmunity; D004854:Herpesvirus 4, Human / Q000276:immunology; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D023421:Models, Animal; D017464:Receptors, Complement 3d / Q000737:chemistry / Q000502:physiology*; D011991:Receptors, Virus / Q000502:physiology
chemical_list: D017464:Receptors, Complement 3d; D011991:Receptors, Virus