Polymorphism of MMP-3 gene and imbalance expression of MMP-3 / TIMP-1 in articular cartilage are associated with an endemic osteochondropathy, Kashin- Beck disease

Table 3 Immunohistochemical expression of MMP-3、TIMP-1 in different layers of the articular cartilage of the three groups

Item	Groups	n	Positive rate (%)
Item	Groups	n	Upper layer	Middle layer	Deeper layer	Total layers
MMP-3	Control	21	46.50 ± 15.82	34.19 ± 16.00	15.48 ± 8.54	32.06 ± 6.74
	KBD	22	63.65 ± 19.78^*	59.83 ± 20.54^*	3.05 ± 20.92^*	51.34 ± 15.07^*
	OA	15	56.84 ± 20.02	57.81 ± 25.58^*	38.68 ± 31.02^*	51.09 ± 14.93^*
TIMP-1	Control	21	45.78 ± 21.27	32.91 ± 16.87	16.55 ± 11.76	31.75 ± 9.87
	KBD	22	24.89 ± 22.11^*	20.22 ± 12.53^*	7.06 ± 5.98^*	17.42 ± 8.09^*
	OA	15	20.38 ± 13.75^*	22.21 ± 11.69^*	7.44 ± 13.77^*	16.67 ± 7.88^*

ISSN: 1471-2474