Activation signal transduction by proline-rich tyrosine kinase 2 (PYK2) in peripheral blood mononuclear cells from patients with systemic lupus erythematosus

Association study of CD154 polymorphisms and serum CD154 level with systemic lupus erythematous in Chinese population

The aim of this study was to investigate the association of three polymorphisms of CD154 with risk of SLE in Chinese population. The study population comprised 770 Chinese individuals, including 350 SLE patients and 420 healthy controls. The gene polymorphism was measured using Snapshot SNP genotyping assays and confirmed by sequencing. Serum CD154 (sCD154) level was measured by ELISA. Compared with control group, sCD154 levels were significantly increased in case group (P < 0.001). The minor C allele of rs1126535 was associated with a significantly increased risk of SLE as compared to the major T allele (P < 0.001). Furthermore, an increased frequency of C-G-A haplotype was also detected in case group which associated with an increased risk of SLE (P = 0.009). Notably, patients carrying rs1126535CT/CC genotypes had a higher sCD154 level compared with that carrying rs1126535TT genotype (P < 0.05). Unfortunately, analyses on the association between rs1126535 and several clinical manifestations of SLE failed to find any significant results. In conclusion, these results indicated that CD154 gene polymorphisms may associate with the risk of SLE and may play regulation role in the expression of sCD154 in SLE patients.

The focal adhesion kinase inhibitor PF-562,271 impairs primary CD4+ T cell activation

The focal adhesion kinase inhibitor, PF-562,271, is currently in clinical development for cancer, however it is not known how PF-562,271 affects T cell function. Here, we demonstrate inhibitory effects of PF-562,271 on the activation of primary human and mouse T cells. PF-562,271 inhibits T cell receptor signaling-induced T cell adhesion to intercellular adhesion molecule-1 and T cell interactions with antigen-presenting cells. An additional focal adhesion kinase inhibitor, PF-573,228, and genetic depletion of focal adhesion kinase also impair T cell conjugation with antigen-presenting cells. PF-562,271 blocks phosphorylation of the signaling molecules zeta chain associate protein of 70 kDa, linker of activated T cells, and extracellular signal-regulated kinase, and impairs T cell proliferation. The effects observed on T cell proliferation cannot solely be attributed to focal adhesion kinase inhibition, as genetic depletion did not alter proliferation. The effect of PF-562,271 on T cell proliferation is not rescued when proximal T cell receptor signaling is bypassed by stimulation with phorbol-12-myristate-13-acetate and ionomycin. Taken together, our findings demonstrate that focal adhesion kinase regulates integrin-mediated T cell adhesion following T cell receptor activation. Moreover, our findings suggest that PF-562,271 may have immunomodulatory effects that could impact its therapeutic applications.