Table 3. Simultaneous expression of OspC, DbpA and DbpB was unable to restore the rpoS mutant with infectivity ^a.

	No. of cultures positive/total specimens examined				No. of mice infected/total mice inoculated
Clone	Heart	Joint	Skin	All sites
ΔrpoS/rpoS	6/6	6/6	6/6	18/18	6/6
ΔrpoS/E22	0/6	0/6	0/6	0/18	0/6
ΔrpoS/ospC′	0/6	0/6	0/6	0/18	0/6
ΔrpoS/C′B′A′	0/6	0/6	0/6	0/18	0/6
13A/C′B′A′	6/6	6/6	6/6	18/18	6/6

^aGroups of six SCID mice were inoculated with 10⁵ organisms of the transformant ΔrpoS/rpoS, ΔrpoS/E22, ΔrpoS/ospC′, ΔrpoS/C′B′A′ or 13A/C′B′A′ and sacrificed 1 month later. Heart, tibiotarsal joint and skin specimens were harvested for spirochete culture.