Anti-inflammatory activity of the A172 vaccine.

<p>A172 modulates transcription of the genes coding for pro-inflammatory cytokines (TNF-α, INF-γ and IL-1β) and induces transcription of the genes coding for anti-inflammatory cytokines (Il-4 and Il-6).</p

Active protection of A172 in mice challenged with <i>S. aureus</i> strain A170.

a<p>Colony forming units per g of kidneys (experiments 1–4) or lungs (experiment 5); values calculated on 3 mice.</p>b<p>Two tailed Fisher's exact test.</p>c<p>A172 Live.</p>d<p>Intramuscular.</p>e<p>P<0.001.</p>f<p>Heat killed A172.</p

Phage M^SA is inhibited by N-acetyl-glucosamine (GlcNAc), the teichoic acid from A170 (A170^TA) or by treatment with N-acetyl-glucosaminidase (GlcNA-ase) from <i>Canavalia ensiformis</i>; phage M^SA is not inhibited by the teichoic acid from A172 (A172^TA) or glucose.

<p>(A) GlcNAc inhibits the lysis of the A170 strain by the phage M^Sa, while glucose (B) does not. (C) A170^TA inhibits the lysis of the A170 strain by the phage M^SA, while A172^TA does not. (D) The phage-sensitive strain A170 grows in the presence of the M^Sa phage, if pre-treated with GlcAc-ase (4 U/tube; 2 h at 37°C).</p

Pulsed field electrophoresis pattern of <i>Sma I</i> digests from the <i>Staphylococcus aureus</i> A170 strain.

<p>The A172 strain (not shown) displayed an identical pattern. M: DNA Size Standard, Lambda Ladder (Concatemers of λ cl857 Sam7) (Bio-Rad Laboratories, Hercules, CA).</p

Differences between the phage M^Sa-sensitive strain A170 and the phage M^Sa-resistant strain A172.

<p>The strain A172 grows in larger clumps (A) compared to the strain A170 (B). Bacteria were grown in liquid culture and collected for microscopic examination at the early stationary phase. (C) The A172 strains displays also a slower growth rate, compared to A170.</p

Gas liquid chromatography profile of monosaccharides obtained by acid hydrolysis of the capsular polysaccharide from <i>S. aureus</i> A172.

<p>Abundance expresses the relative ratio between monosaccharides.</p

Mouse anti A172-HK antibodies protect mice challenged with <i>S. aureus</i> A170 strain.

a<p>Colony forming units per g of kidneys; values calculated on 3 mice.</p>b<p>Two tailed Fisher's exact test.</p>c<p>Intramuscular.</p>d<p>P<0.0001.</p

Protection of heat killed vaccine A172 administered by aerosol.

a<p>Colony forming units per g of kidneys; values calculated on 3 mice.</p>b<p>Two tailed Fisher's exact test.</p>c<p>Heat killed A172.</p>d<p>Aerosol.</p>e<p>P<0.001.</p

Expression levels of <i>S. aureus</i> A170 and A172 virulence factors.

<p>Acquisition of phage-resistance by A172 is accompanied by extensive alterations in virulence gene expression levels. Out of the 14 ORFs examined, 13 are significantly under-expressed, compared to the phage-sensitive strain A170. Bacteria were collected for transcriptional analysis during the exponential growth phase. SA0107 (<i>spa</i>, IgG binding protein A precursor); SA0112 (hypothetical protein, similar to cysteine synthase); SA0184 (hypothetical protein); SA039 (<i>geh</i>; glycerol ester hydrolase); SA1007 (α-haemolysin); SA1160 (<i>nuc</i>; thermonuclease); SA1898 (hypothetical protein, similar to SceD precursor); SA2097 (hypothetical protein, similar to secretory antigen precursor SsaA); SA2206 (<i>sbi</i>; IgG-binding protein SBI); SA2255 (oligopeptide transporter substrate binding protein); SA2406 (<i>gbsA</i>; glycine betaine aldehyde dehydrogenase gbsA); SA2459 (<i>ica</i>; N-glycosyltransferase); SAR216 (<i>groEL</i>; chaperonin GROEL); SAR2117 (<i>groES</i>; co-chaperonin GRES). ORFs numbers correspond to the <i>S. aureus</i> N315 genome sequence. Gene designations (when known) and proteins function are shown in parentheses.</p

In <i>S. aureus</i>, phage-resistance comes with production of capsular polysaccharide.

<p>(A) Strains A170, A177, A179, A181 (sensitive to the phages M^SA, M^SA1, M^Sa2, M^SA3, respectively). (B) Strains A172, A178, A180, A182 (resistant to the phages M^SA, M^SA1, M^Sa2, M^SA3, respectively).</p