Table 3.

Weight loss and lesion development in mice inoculated subcutaneously with GASa

Experiment (inoculum)Strain or descriptionMean 24-h weight gain ± SDNo. with lesions/no. inoculatedbNo. with necrosis/no. with lesionsb
I (3 × 105)MGAS166 (wt)1.3 ± 0.40/60/0
csrR::Tn916(muc5)0.6 ± 0.51/60/1
ΔcsrR csrS −1.7 ± 1.64/63/4
ΔcsrR csrS ΔhasAB −0.1 ± 0.95/61/5
II (2 × 106)Controlc 0.6 ± 0.070/60/0
MGAS166 (wt)−0.4 ± 1.20/60/0
csrR::Tn916(muc5)−3.7 ± 0.86/66/6
ΔcsrR csrS −4.3 ± 0.66/66/6
ΔcsrR csrS ΔhasAB −3.4 ± 0.86/65/6
III (2 × 105)Controld 0.5 ± 0.60/80/0
MGAS166 (wt)0.9 ± 0.40/60/0
csrR::Tn916(muc5)0.2 ± 1.40/70/0
ΔcsrR csrS −2.1 ± 1.73/63/3
ΔcsrR csrS ΔhasAB 0.4 ± 1.31/60/1
IV (4 × 106)Controlc 1.2 ± 0.40/60/0
MGAS166 (wt)1.1 ± 0.34/120/4
csrR::Tn916(muc5)−3.1 ± 0.66/66/6
csrR::Tn916(muc7)−3.3 ± 0.66/66/6
ΔcsrR csrS −3.7 ± 0.412/1212/12
ΔcsrR csrS ΔhasAB −1.6 ± 0.96/64/6
  • a All bacteria were grown in Todd-Hewitt broth at 37°C to mid-exponential phase (A 600 = 0.6 to 0.7). Culture conditions were as follows: experiment I, shaken and aerated; experiment II, shaken and aerated; experiment III, static and capped; experiment IV, static and capped. wt, wild type.

  • b Counts taken at 72 h.

  • c Control mice were uninoculated mice from the same cohort.

  • d Control mice received subcutaneous injections of THY broth.