Ligands for programmed cell death 1 gene in patients with systemic lupus erythematosus

Objective. To investigate the role of ligands for programmed cell death 1 (PD-L) in the pathogenesis of systemic lupus erythematosus (SLE). Methods. One hundred sixty-four patients with SLE and 160 healthy controls were enrolled in our study. The PD-L1 and PD-L2 polymorphisms were determined by polymerase chain reaction (PCR)/direct sequencing or restriction fragment length polymorphism (RFLP)-PCR. Results. The genotype distributions of PD-L2 47103 C/T polymorphisms in patients with SLE were significantly different from those of the controls (p = 0.003). The genotype frequency of PD-L2 47103 T/T, in comparison with 47103 C/C, was significantly increased in patients with SLE when compared with that of the controls (odds ratio 2.5, 95% confidence interval 1.4-4.4, p = 0.001). A similar finding could also be found in the allele frequency of PD-L2 47103 T (SLE vs control, OR 1.7, 95% CI 1.3-2.4, p = 0.001). There were no significant differences in the genotype and allele frequencies of PD-L1 polymorphisms between the patients and controls. Conclusion. PD-L2 47103 T may be associated with susceptibility to SLE in Taiwan.