This study reports the detection of an extracellular staphylococcal product, designated secretory inhibitor of platelet microbicidal protein (SIPMP), that causes local inhibition of the bactericidal action of platelet microbicidal protein (PMP) in the fluid phase. Urethral isolates of Staphylococcus aureus (n=24) and coagulase-negative staphylococci (CNS) (n=47) from patients with or without chronic bacterial prostatitis (CBP) were tested. SIPMP production was tested by inhibition of PMP bioactivity against Bacillus subtilis and was expressed as percentage inhibition of PMP bactericidal activity. The PMP susceptibility of staphylococcal strains was determined by exposing bacterial cells to serial dilutions of PMP. Staphylococci from patients without CBP produced SIPMP at levels of 10.3±1.2 and 13.25±1.72 % for S. aureus and CNS, respectively. Strains isolated from men with CBP inhibited PMP-induced killing of B. subtilis by 23.38±4.2 % (P<0.05) and 23.69±1.87 % (P<0.01) for S. aureus and CNS, respectively. SIPMP production correlated with staphylococcal resistance to PMP (r2=0.6082 and 0.7264 for S. aureus and CNS, respectively). SIPMP represents a hitherto unrecognized determinant of staphylococcal pathogenicity. These results suggest that SIPMP production is associated with the CBP source. Data from this study may have significant implications for the understanding of the pathogenesis of CBP.
BukharinO. V.,
BrudastovI. A.,
GritsenkoV. A.,
DeriabinD. G.1996; Role of the ability of bacteria to inactivate natural anti-infective resistance factors in their resistance to blood bactericidal action (blood serum). Biull Eksp Biol Med 121:174–176[CrossRef]
ComE.,
BourgeonF.,
EvrardB.,
GanzT.,
ColleuD.,
JégouB.,
PineauC.2003; Expression of antimicrobial defensins in the male reproductive tract of rats, mice, and humans. Biol Reprod 68:95–104
DankertJ.1988; Role of platelets in early pathogenesis of viridans group streptococcal endocarditis: a study on thrombodefensins
. PhD thesis University of Groningen; Groningen, The Netherlands:
DankertJ.,
van der WerffJ.,
ZaatS. A. J.,
JoldersmaW.,
KleinD.,
HessJ.1995; Involvement of bactericidal factors from thrombin-stimulated platelets in clearance of adherent viridans streptococci in experimental infective endocarditis. Infect Immun 63:663–671
DeckersD.,
MasschalckB.,
AertsenA.,
CallewaertI.,
van TiggelenC. G. M.,
AtanassovaM.,
MichielsC. W.2004; Periplasmic lysozyme inhibitor contributes to lysozyme resistance in Escherichia coli
. Cell Mol Life Sci 61:1229–1237[CrossRef]
DhawanV. K.,
YeamanM. R.,
CheungA. L.,
KimE.,
SullamP. M.,
BayerA. S.1997; Phenotypic resistance to thrombin-induced platelet microbicidal protein in vitro is correlated with enhanced virulence in experimental endocarditis due to Staphylococcus aureus
. Infect Immun 65:3293–3299
DürrM.,
PeschelA.2002; Chemokines meet defensins: the merging concepts of chemoattractants and antimicrobial peptides in host defense. Infect Immun 70:6515–6517[CrossRef]
EveraertK.,
MahmoudA.,
DepuydtC.,
MaeyaertM.,
ComhaireF.2003; Chronic prostatitis and male accessory gland infection – is there an impact on male infertility (diagnosis and therapy)?. Andrologia 35:325–330[CrossRef]
Fernie-KingB. A.,
SeillyD. J.,
DaviesA.,
LachmannP. J.2002; Streptococcal inhibitor of complement inhibits two additional components of the mucosal innate immune system: secretory leukocyte proteinase inhibitor and lysozyme. Infect Immun 70:4908–4916[CrossRef]
HoeN. P.,
Vuopio-VarkilaJ.,
VaaraM. & 7 other authors; 2001; Distribution of streptococcal inhibitor of complement variants in pharyngitis and invasive isolates in an epidemic of serotype M1 group A Streptococcus infection. J Infect Dis 183:633–639[CrossRef]
IvanovI. B.2005; I n vitro resistance to human platelet microbicidal protein among urethral staphylococcal and enterococcal isolates with its correlation with prostatitis. Indian J Med Microbiol 23:253–255
KrijgsveldJ.,
ZaatS. A. J.,
MeeldijkJ. & 9 other authors; 2000; Thrombocidins, microbicidal proteins from human platelets, are C-terminal deletion products of CXC chemokines. J Biol Chem 275:20374–20381[CrossRef]
KupferwasserL. I.,
SkurrayR. A.,
BrownM. H.,
FirthN.,
YeamanM. R.,
BayerA. S.1999; Plasmid-mediated resistance to thrombin-induced platelet microbicidal protein in staphylococci: role of the qacA locus. Antimicrob Agents Chemother 43:2395–2399
KupferwasserL. I.,
YeamanM. R.,
ShapiroS. M.,
NastC. C.,
BayerA. S.2002; In vitro susceptibility to thrombin-induced platelet microbicidal protein is associated with reduced disease progression and complication rates in experimental Staphylococcus aureus endocarditis: microbiological, histopathologic, and echocardiographic analyses. Circulation 105:746–752[CrossRef]
LangleyR.,
WinesB.,
WilloughbyN.,
BasuI.,
ProftT.,
FraserJ. D.2005; The staphylococcal superantigen-like protein 7 binds IgA and complement C5 and inhibits IgA-Fc α RI and serum killing of bacteria. J Immunol 174:2926–2933[CrossRef]
WuT.,
YeamanM. R.,
BayerA. S.1994; In vitro resistance to platelet microbicidal protein correlates with endocarditis source among bacteremic staphylococcal and streptococcal isolates. Antimicrob Agents Chemother 38:729–732[CrossRef]