Polymorphisms in the CD3Z gene influence TCRzeta expression in systemic lupus erythematosus patients and healthy controls.

TCRzeta (CD247) functions as an amplification module in the TCR signaling cascade and is essential for assembly and surface expression of the TCR/CD3 complex. The TCRzeta-chain is down-regulated in many chronic infectious and inflammatory diseases, including systemic lupus erythematosus (SLE). It is unclear whether reduced TCRzeta expression is a cause or a consequence of chronic inflammatory responses.

Polymorphism at the C-reactive protein locus influences gene expression and predisposes to systemic lupus erythematosus.

Relative deficiency of pentraxin proteins is implicated in the pathogenesis of systemic lupus erythematosus. The C-reactive protein (CRP) response is defective in patients with acute flares of disease, and mice with targeted deletions of the serum amyloid P component gene (Sap) develop a lupus-like illness. In humans, the genes for CRP (CRP) and SAP (APCS) map to 1q23.