The Innate Immune Response Against Staphylococcus aureus

Abstract

The innate immune system harbors a multitude of different receptor systems and cells that are constantly prepared to sense and eliminate invading microbial pathogens. Staphylococcus aureus enters the body on its exposed epithelial surfaces, e.g., on skin and mucosa. The initial interaction with epithelial cells is governed by Toll-like receptor (TLR)-2-mediated local production of soluble mediators, including cytokines, chemokines, and antimicrobial peptides. The overall goal is to achieve a steady state of immune mediators and colonizing bacteria. Following cell and tissue invasion clearance of bacteria depends on intracellular microbial sensors and subsequent activation of the inflammasomes. Tissue-resident mast cells and macrophages recruit neutrophils, macrophages, and NK cells. This inflammatory response supports the generation of IL-17 producing NKT, γδ T cells, and T helper cells. Local dendritic cells migrate to the lymph nodes and fine-tune the adaptive immune response. The scope of this chapter is to provide an overview on the major cell types and receptors involved in innate immune defense against S. aureus. By segregating the different stages of infection from epithelial barrier to intracellular and systemic infection, this chapter highlights the different qualities of the innate immune response to S. aureus at different stages of invasiveness.

The many faces of interleukin-17 in inflammatory skin diseases

“…This drives the formation of IL‐17 + innate and adaptive immune cells. The IL‐17 pathway organizes antimicrobial defence mechanisms, especially against Staphylococcus aureus and Candida albicans , by upregulating numerous cytokines, neutrophil‐recruiting chemokines and antimicrobial peptides …”

“…The IL-17 pathway organizes antimicrobial defence mechanisms, especially against Staphylococcus aureus and Candida albicans, by upregulating numerous cytokines, neutrophilrecruiting chemokines and antimicrobial peptides. 9,10 Active participation of the Th17 pathway has been demonstrated in archetypical autoinflammatory syndromes such as familial Mediterranean fever. 5 IL-17 has pleiotropic inflammatory effects leading to release of a broad range of cytokines in a variety of cell types, including epithelial cells, endothelial cells and fibroblasts.…”

Neutralization of MMP-2 and TNFR1 Regulates the Severity of S. aureus-Induced Septic Arthritis by Differential Alteration of Local and Systemic Proinflammatory Cytokines in Mice

“…with resident cells, infiltrating cells like invading macrophages, PMNs also release inflammatory cytokines like TNF-α, IL-6, and Il-1β whereas IFN-γ is mainly released from T cells [69]. Indeed, in our study, mice inoculated with S. aureus displayed significantly higher levels of TNF-α, IL-1β, IFN-γ, and IL-6 than the control animals, though significant variations in the serum (systemic) and synovial (local) levels were observed throughout the experiment.…”

Розвиток Імунної Відповіді При Стафілококовій Пневмонії (Частина 6)

“…Кроме того, тучные клетки обладают уникальной способ-ностью быстро высвобождать такие вазоактивные и иммуностимулирующие медиаторы, как фактор не-кроза опухоли β (TNF-β), гистамин, триптаза и хи-маза, во внеклеточную среду, в том числе и во время пневмонии, вызванной Staphylococcus aureus [3,33].…”

“…Представляет интерес тот факт, что агонисты TLR7 и TLR9, вызывающие продукцию IFN-α, подавляют продукцию IL-17 [5]. Ингибирующее действие IFN-α на продукцию IL-17, вероятно, имеет опосредованный характер и обусловлено тем, что IFN-α индуцирует синтез IL-17-ингибирующего цитокина IL-27 [3]. Продукты бактерий Staphylococcus aureus модули-руют функционирование DC за счет киллинга DC, ингибирование Th 1 -ответа, индуцирование Th 2 -и Treg-ответов, а также усиление пролиферации B-клеток, продуцирующих IL-10.…”