This is contrary to the reduced IL-6 and TNF levels observed in response to MSU crystal injection into the synovium-like subcutaneous air pouch of POP1TG mice, indicating that the reduced cytokine levels observed in vivo during gout are likely secondary to the POP1-mediated reduction of pro-inflammatory cell infiltration, rather than a direct effect of POP1 on NF-κB mediated cytokine expression. This evidence concerns the gene POP1 and gout.