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Role of caspase in CD80 expression of superantigen-stimulated monocytes

Fumiaki Shinohara1, Keiko Sato, Maiko Suzuki

  • 1Department of Microbiology and Immunology, Tohoku University Graduate School of Dentistry, Aoba-ku, Sendai 980-8575, Japan.

International Journal of Molecular Medicine
|July 16, 2004
PubMed

Insights

Staphylococcal enterotoxin B (SEB) induces CD80+ monocytes via caspase activation. Inhibiting caspases or NF-kappaB reduces this monocyte response, crucial for T-cell activation.

Area of Science:

  • Immunology
  • Cell Biology

Background:

  • Staphylococcal enterotoxin B (SEB) is a superantigen known to induce massive T-cell activation.
  • Monocytes play a critical role in immune responses, including antigen presentation.

Purpose of the Study:

  • To investigate the mechanism by which SEB induces CD80+ monocytes.
  • To elucidate the role of caspases and NF-kappaB in SEB-mediated monocyte activation.

Main Methods:

  • ব্যবহৃত হয়েছে স্ট্যাফিলোকক্কাল এন্টারোটক্সিন বি (SEB) এবং ইঁদুর মনোসাইট।
  • NF-kappaB ইনহিবিটর (PDTC) এবং ক্যাস্পেস ইনহিবিটর (z-VAD-fmk) ব্যবহার করে পরীক্ষা করা হয়েছে।
  • ফ্লো সাইটোমেট্রি ব্যবহার করে CD80+ মনোসাইটের শতাংশ পরিমাপ করা হয়েছে।

Main Results:

  • SEB-induced CD80+ monocytes were significantly reduced by PDTC, an NF-kappaB inhibitor.
  • SEB activated both NF-kappaB and caspases (-3 and -8).
  • Caspase inhibition by z-VAD-fmk prevented apoptosis and reduced CD80+ monocyte generation.

Conclusions:

  • CD80 expression on monocytes induced by SEB is regulated by caspase activity.
  • NF-kappaB activation, downstream of caspase action, is essential for SEB-induced CD80+ monocyte generation.
  • This pathway highlights a novel mechanism for monocyte involvement in SEB-driven T-cell activation.

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