Human Endogenous Retrovirus W Activity in Cartilage of Osteoarthritis Patients

Table 3

Prevalence of dsRNA, syncytin-1, and HERV-like particles in samples from OA and non-/early OA patients.

Material/method	IF syncytin	IF dsRNA	IEM syncytin	IEM dsRNA	TEM VLP	TEM budding
Chondrocytes OA	20/22* (S)**	20/22 (S)	7/7 (S)	7/7 (S)	6/7	5/7
Cartilage OA			7/7 (S)	7/7 (S)	22/24	16/24
Chondrocytes non-OA	4/7 (3 W, 1 S)	3/7 (2 W, 1 S)	4/7 (3 W, 1 S)	3/7 (2 W, 1 S)		1/8
Cartilage non-OA			3/5 (2 W, 1 S)	3/5 (2 W, 1 S)
Collagenase-treated supernatants OA					3/4

∗Number of positive samples/total number of samples.
**S: strong staining; W: weak staining; VLP: virus-like particles.