English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The ability of macrophages to catabolize antigens is relevant both as a means to process complex antigens before presentation to T cells and as a way to down-regulate immune responses by destroying the antigenicity of polypeptides. With these considerations in mind, we investigated the regulation of macrophage catabolic activity by lipopolysaccharide (LPS). Catabolic activity was quantitated by following the distribution and molecular form of 125I-labeled surface components of heat-killed Listeria monocytogenes after their uptake by macrophages. We compared the catabolic activity of macrophages from peritoneal exudates of mice injected intraperitoneally with saline or LPS and found that LPS-elicited macrophages displayed a greatly enhanced (threefold) rate of catabolism. This increase in catabolic activity peaked 3 days after LPS injection and slowly declined thereafter, approaching a base-line level after 3 weeks. The enhancement of catabolic activity was under Lps gene control. Macrophages that were elicited 3 days after intraperitoneal injection of LPS rapidly destroyed the antigenicity of bacterial antigens, expressed low levels of Ia molecules, and processed and presented antigen slowly when tested as antigen-presenting cells in vitro. We also showed that an injection of LPS before infection with L. monocytogenes resulted in diminished development of T-cell reactivity to this organism. These results suggest that LPS elicits a macrophage population specialized for antigen degradation functions, with negative regulatory effects on the induction of specific immune responses.

infection and immunity

An early response to lipopolysaccharide is the elicitation of macrophages specialized for antigen degradation with negative regulatory effects on the induction of specific immune responses