After LPS stimulation, monocytes from healthy subjects produced higher amounts of STAT3 (healthy versus APS; 0.085 ± 0.017 versus 0.017 ± 0.003, P = 0.0007) compared to APS cells, while CCL2 mRNAs (0.05 ± 0.01 versus 0.183 ± 0.048, P = 0.03) were higher in monocytes isolated from APS patients. This evidence concerns the gene STAT3 and autoimmune polyendocrinopathy.