Table 1.

Histopathological assessment of arthritis severity in tibiotarsal joint sections from Borrelia burgdorferi-infected C3H/HeN mice 16 and 44 days after infection.

	16 days p.i.			44 days p.i.
	Bb n = 7	BbHg n = 7	P-value	Bb n = 7	BbHg n = 7	P-value
Neutrophils infiltration	0 (0–2)	0 (0–0)	n.s.	0 (0–2)	0 (0–0)	n.s.
Mononuclear cell infiltration	1 (1–3)	0 (0–0·5)	P = 0·001	0 (0–1)	1 (0–1)	n.s.
Synovia thickness	2 (1–3)	0 (0–0·5)	P = 0·001	1 (1–2)	2 (0–3)	n.s.
Cartilage hyperplasia	1 (0–1)	0 (0–0)	P = 0·026	0 (0–1)	1 (0–1)	n.s.

Median values (range in parenthesis) of scores are given. The scores for all parameters ranged from 0 (normal) to 3 (severe). p.i., post-immunization, Bb, B. burgdorferi-infected mice, BbHg, B. burgdorferi-infected mice treated with HgCl₂. P-values refer to comparisons using the Mann–Whitney U-test; n.s.: non-significant.