当前位置： SCI文献检索 > INTERNATIONAL IMMUNOLOGY期刊下所有文献 > TLR2-dependent recognition of Streptococcus suis is modulated by the presence of capsular polysaccharide which modifies macrophage responsiveness.

TLR2-dependent recognition of Streptococcus suis is modulated by the presence of capsular polysaccharide which modifies macrophage responsiveness.

Abstract：

:Streptococcus suis capsular type 2 is an important swine pathogen and an agent of zoonosis. Although meningitis is the most common form of disease, septicemia and septic shock are also frequently reported. Despite reports that CD14 is involved in the recognition of encapsulated S. suis by host cells, the mechanisms underlying exacerbated release of pro-inflammatory cytokines, which may have a negative impact on disease outcome, are unclear. Here, we demonstrated that stimulation of human monocytes by whole encapsulated S. suis or its purified cell wall components influences the relative expression of Toll-like receptor (TLR)-2 and CD14 mRNA. Moreover, this stimulation triggered the release of cytokines (tumor necrosis factor-alpha, IL-1beta and IL-6) and chemokines (IL-8 and monocyte chemoattractant protein-1), which was significantly reduced by antibody-mediated blocking of TLR2 but not TLR4. Mouse macrophages deficient in TLR2 also showed impaired cytokine responses to encapsulated bacteria. Given that this response was completely abrogated in myeloid differentiation factor 88 (MyD88)-deficient macrophages, other TLRs might also be involved. Furthermore, we demonstrated that the presence of capsular polysaccharide (CPS)-modulated S. suis interactions with TLRs. In the absence of CPS, uncovered cell wall components induced cytokine and chemokine production via TLR2-dependent as well as -independent pathways, whereas CPS contributes to MCP-1 production in a MyD88-independent manner. Overall, this study contributes to a better understanding of the inflammatory processes induced by an encapsulated pathogen and suggests that the relative expression of CPS, known to be modulated during bacterial invasion and dissemination in the host, might alter interactions with host cells and, consequently, the outcome of the inflammatory response.

journal_name

Int Immunol

journal_title

International immunology

authors

Graveline R,Segura M,Radzioch D,Gottschalk M

doi

10.1093/intimm/dxm003

subject

Has Abstract

pub_date

2007-04-01 00:00:00

pages

375-89

issue

eissn

0953-8178

issn

1460-2377

pii

dxm003

journal_volume

pub_type

杂志文章

在线工具

TLR2-dependent recognition of Streptococcus suis is modulated by the presence of capsular polysaccharide which modifies macrophage responsiveness.