In addition, MMP7 is involved in the breakdown of extracellular matrixes during disease processes, such as arthritis and cancer metastases (Ye et al., 2007; Xu et al., 2016), among which arthritis is a typical symptom caused by H. parasuis; COX2 has been associated with HIV Tat-induced up-regulation of tight junction protein and disruption of the integrity of the blood-brain barrier (Pu et al., 2007). The gene discussed is MMP7; the disease is arthritic joint disease.