Table 1.
Virulence determinants of CA-MRSA evaluated in animal infection models using isogenic deletion mutants
| Protein | Gene(s) | Model/animal | Bacterial strain | Result | Conclusion | Remarks | Ref. |
|---|---|---|---|---|---|---|---|
| α-toxin | hla | Pneumonia, mice (C57BL/6J) | LAC (USA300) | Strong reduction of mortality in hla mutant | α-toxin is a crucial virulence determinant in mouse pneumonia. | No effect for lukSF (PVL) deletion in same strain and model | 87 |
| α-toxin | hla | Pneumonia, mice (C57BL/6J) | LAC (USA300), MW2 (USA400) | Protection from pneumonia by anti-Hla antibodies | α-toxin is a crucial virulence determinant in mouse pneumonia. | No protection achieved using anti-PVL antisera | 94 |
| PSMα | psmα1, psmα2, psmα3, psmα4 | Abscess, mice (SKH1-hrBR) bacteremia, mice (CD1 Swiss) | LAC (USA300): abscess MW2 (USA400): bacteremia | Strong reduction in mortality and abscess formation | α-PSMs are crucial virulence determinants in mouse skin infection and sepsis. | Results directly comparable to δ-toxin, PSMα | 51 |
| δ-toxin | hld | Abscess, mice (SKH1-hrBR) bacteremia, mice (CD1 Swiss) | LAC (USA300): abscess MW2 (USA400): bacteremia | Small (insignificant) reduction in mortality and abscess formation | δ-toxin is not a significant virulence determinants in mouse skin infection and sepsis. | Results directly comparable to PSMα, PSMβ | 51 |
| PSMα | psmα1, psmα2 | Abscess, mice (SKH1-hrBR) bacteremia, mice (CD1 Swiss) | LAC (USA300): abscess MW2 (USA400): bacteremia | No reduction in mortality and abscess formation | α-PSMs do not impact mouse skin infections and sepsis. | Results directly comparable to PSMα, δ-toxin | 51 |
| ACME | 37 kb ACME fragment containing arc and opp loci | Bacteremia, rabbits | SF8300 (USA300) | Significantly more wild-type than ACME mutant bacteria at end of experiment | ACME is a significant contributor to rabbit sepsis. | Highly discriminative competition model | 96 |
| PVL | lukS, lukF | Abscess, mice (SKH1-hrBR) bacteremia, mice (CD1 Swiss) | LAC (USA300), MW2 (USA400) | No significant differences | PVL is not a virulence determinant in mouse sepsis or skin infections. | 86 | |
| PVL | lukS, lukF | Pneumonia, mice (C57BL/6J) | LAC (USA300) | No reduction of mortality in lukSF mutant | PVL is not a virulence determinant in mouse pneumonia. | Strong effect for hla deletion in same strain and model | 87 |
| PVL | lukS, lukF | Pneumonia, mice (C57BL/6J) | LAC (USA300), MW2 (USA400) | No protection from pneumonia by anti-PVL antibodies | PVL is not a virulence determinant in mouse pneumonia. | Protection achieved using anti-Hla antisera in same model | 87 |
| PVL | lukS, lukF | Pneumonia, mice (BALB/cJ, BALB/cAnNHsd), skin infection, mice (BALB/cJ, BALB/cAnNHsd) | LAC (USA300) | No significant effect of PVL | PVL is not a virulence determinant in mouse pneumonia or skin infection. | 88 | |
| PVL | lukS, lukF | Bacteremia, rabbits | SF8300, LAC (USA300), MW2 (USA400) | Transiently significantly more wild-type than lukSF mutant bacteria, but not at end of experiment | PVL has a modest, transient effect on the progress of rabbit bacteremia. | Highly discriminative competition model | 85 |
| PVL | lukS, lukF | Necrotizing pneumonia, rats | LAC (USA300) | No significant effect of PVL | PVL is not a virulence determinant in rat pneumonia. | No significant effect of PVL on expression of host inflammatory genes | 89 |
| PVL | lukS, lukF | Necrotizing pneumonia and skin infection, mice (BALB/c) | LAC (USA300) | PVL impacts necrotizing pneumonia and skin infection in mice. | PVL is a virulence determinant in mouse pneumonia and skin infection. | Only study showing a prolonged effect of PVL in experimental disease. | 90 |
| Anti-PVL antibodies protect from infection. |