Interaction between Human Polymorphonuclear Leukocytes and Streptococcus milleri Group Bacteria

Abstract

Because Streptococcus milleri group (SMG) bacteria--Streptococcus constellatus, Streptococcus intermedius, and Streptococcus anginosus--exhibit a striking propensity to cause abscesses, the interaction of these organisms with human polymorphonuclear leukocytes (PMNL) was examined. After incubation in pooled normal human serum, SMG stimulated less chemotaxis than did Staphylococcus aureus, in contrast to viridans streptococci, which caused greater chemotaxis than did S. aureus. PMNL ingested greater numbers of SMG and viridans streptococci than S. aureus but killed these organisms more slowly and less completely. Relative resistance to killing by PMNL is expected in organisms that cause abscesses, and inhibition of chemotaxis may contribute to pathogenicity, because delayed arrival of PMNL gives a head start to proliferating bacteria. This study helps explain the capacity of SMG to cause abscesses. It is unclear, however, why viridans streptococci, bacteria that rarely produce abscesses, share some of these same properties.

Baicalin promotes the bacteriostatic activity of lysozyme on S. aureus in mammary glands and neutrophilic granulocytes in mice

“…An increase in the count of neutrophils is a sign of mastitis in mammary glands [21]. While polymorphonuclear leukocytes are the major cell type that control bacterial infections in mammals [22], LYSO is a major component against infection by bacterial pathogens in neutrophils [8]. Previous studies showed that baicalin treatment could significantly reduce the colony count of S. aureus in mammary tissues [15] and in neutrophils [1].…”

Streptococcal Infections in Patients with Chronic Granulomatous Disease: Case Report and Review of the Literature

“…Interestingly, of the three subspecies listed, Streptococcus intermedius was especially associated with abscess formation, hematogenous spread and deep seated infections in the general population [12]. The reason for this predisposition to abscess formation is unclear, but may be related to toxic interactions with polymorphonuclear leukocytes [13]. Moreover, Streptococcus intermedius isolates from our patient did not produce H 2 O 2 .…”

The Pore-Forming Toxin Listeriolysin O Is Degraded by Neutrophil Metalloproteinase-8 and Fails To Mediate Listeria monocytogenes Intracellular Survival in Neutrophils

“…Therefore, the neutrophil's response to LLO likely applies to other CDCs. In accordance with this idea, neutrophils efficiently kill numerous CDC-producing bacteria (87)(88)(89)(90)(91). It would be of considerable interest to study neutrophil degranulation and membrane repair mechanisms in response to various families of pore-forming toxins as well as to evaluate the antitoxin activity of neutrophil GP.…”