These findings suggest allelic variation in this region of CTLA4 is not a major independent risk factor for SLE, but may contribute to risk of disease in younger African-Americans or in the presence of certain immunogenetic markers.
We searched all the publications about the association between CTLA-4) promoter exon-1 +49 and 1722T/C polymorphism and SLE from PubMed, Elsevier Science Direct, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI), and Wanfang (Chinese).
These findings suggest allelic variation in this region of CTLA4 is not a major independent risk factor for SLE, but may contribute to risk of disease in younger African-Americans or in the presence of certain immunogenetic markers.
To determine whether 7 candidate genes, including tumor necrosis factor receptor II, bcl-2, CTLA-4, interleukin-10 (IL-10), CD19, Fcy receptor type IIA (CD32), and IL-1 receptor antagonist, may contribute to susceptibility to systemic lupus erythematosus (SLE) in the Italian population.
These results indicate that CTLA-4 exon 1 polymorphism does not contribute greatly to the susceptibility to RA and SLE, at least in Japanese, although the presence of CTLA4 49G allele could be a minor predisposing factor for RA in HLA-DRB1*0405-positive individuals.
Further investigations are required to identify whether other at-risk polymorphisms within CTLA-4 confer a risk of SLE and to clarify the role of the CTLA-4 gene.
These data suggest that high expression of Fas, FasL and IL-6 and low expression of CTLA-4 by the CD8<sup>+</sup>CD28<sup>+</sup> T-cell subset promotes the activation-induced cell death of the CD8<sup>+</sup>CD28<sup>+</sup> T-cell subset, resulting in an imbalance of CD8<sup>+</sup>CD28<sup>-</sup>/CD8<sup>+</sup>CD28<sup>+</sup> T cells in active SLE patients, which represents an important feature in the immunological pathogenesis of SLE.
The programmed cell death 1 gene (PDCD1), the cytotoxic T-lymphocyte-associated protein 4 (CTLA4) gene, and the methyl-CpG-binding protein 2 gene (MECP2) are considered to be the candidate genes associated with SLE.
Our results suggest that the -1661AG and -1722TC polymorphisms in the promoter region of the CTLA-4 gene does not play any role in genetic susceptibility to SLE.
Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is important in regulating T cell-mediated immunity, encompassing the first line of response to viral infections, and genetic variation in CTLA-4 has been associated with SLE.
Disorders of the CTLA-4 gene, especially a GG genotype in exon 1 at +49 and/or 106-bp fragment length of the 3'UTR in exon 4, may be involved in early development of SLE in Japanese children, such as the boys described here.