A study on the association of autoantibodies, chemokine, and its receptor with disease activity in systemic lupus erythematosus in North Indian population

Gq-Coupled Receptors in Autoimmunity

Heterotrimeric G proteins can be divided into Gi, Gs, Gq/11, and G12/13 subfamilies according to their α subunits. The main function of G proteins is transducing signals from G protein coupled receptors (GPCRs), a family of seven transmembrane receptors. In recent years, studies have demonstrated that GPCRs interact with Gq, a member of the Gq/11 subfamily of G proteins. This interaction facilitates the vital role of this family of proteins in immune regulation and autoimmunity, particularly for Gαq, which is considered the functional α subunit of Gq protein. Therefore, understanding the mechanisms through which Gq-coupled receptors control autoreactive lymphocytes is critical and may provide insights into the treatment of autoimmune disorders. In this review, we summarize recent advances in studies of the role of Gq-coupled receptors in autoimmunity, with a focus on their pathologic role and downstream signaling.

Chemokine receptor 5 Δ32 polymorphism and systemic lupus erythematosus, vasculitis, and primary Sjogren's syndrome. Meta-analysis of possible associations

OBJECTIVE

The aim of this study was to determine whether the functional chemokine receptor 5 delta32 (CCR5-Δ32) polymorphism is associated with susceptibility to systemic lupus erythematosus (SLE), vasculitis, and primary Sjogren's syndrome (pSS).

RESULTS

A total of 12 studies were analyzed, including 5 on SLE, 5 on vasculitis, and 2 on pSS, encompassing 1881 patients and 2391 controls. Meta-analysis indicated no association between SLE and the CCR5-Δ32 allele (OR 0.842, 95 % CI 0.793-1.804, p = 0.657), and no association between the CCR5-Δ32 allele and SLE in Europeans (OR 0.647, 95 % CI 0.306-1.368, p = 0.255). Meta-analysis of the CCR5-Δ32 allele and the Δ32Δ32 + Δ32 W genotype showed no association with lupus nephritis (LN; OR 1.771, 95 % CI 0.475-6.595, p = 0.395; OR 2.192, 95 % CI 0.182-26.42, p = 0.537, respectively). In addition, meta-analysis revealed no association between the CCR5-Δ32 allele and vasculitis in all study subjects and in Europeans (OR 1.241, 95 % CI 0.951-1.620, p = 0.111; OR 1.359, 95 % CI 0.803-2.303, p = 0.254, respectively). However, the overall OR for the CCR5-Δ32 allele was significantly higher in Kawasaki disease (KD; OR 1.746, 95 % CI 1.003-2.955, p = 0.038) and the meta-analysis of the Δ32Δ32 + Δ32 W genotype showed a trend indicating an association with KD (OR 1.683, 95 % CI 0.921-3.077, p = 0.091). No association was found between the CCR5-Δ32 polymorphism and pSS.

CONCLUSION

This meta-analysis demonstrates that the CCR5-Δ32 polymorphism is associated with KD, but does not facilitate susceptibility to SLE, LN, or pSS.