Role of innate immune cells in protection against Toxoplasma gondii at inflamed site.

Abstract

The intraperitoneal infection with Toxoplasma gondii (T. gondii) caused accumulation of gamma delta T, NK, NK1.1+T-like (NKT) cells at inflamed sites. To clarify the roles of these cells in protection against T. gondii at the inflamed sites, BALB/c mice were depleted of gamma delta T, NK, NK and NKT cells by treatment with antibody against TCR-gamma delta, asialoGM1 or Interleukin-2 receptor beta-chain (IL-2 R beta), respectively, prior to infection. Mice treated with anti-TCR-gamma delta monoclonal antibody (mAb) became more susceptible to infection, whereas mice treated with anti-IL-2R beta mAb acquired resistance. Treatment with anti-asialoGM1 Ab showed no effect. We previously reported that heat shock protein 65 (HSP65) in macrophages induced by gamma delta T cells plays an essential role in protective immunity against T. gondii infection, by preventing apoptotic death of infected macrophages. In the present study, we showed that treatment with anti-IL-2R beta mAb, but not with anti-asialoGM1 Ab, enhanced the HSP65 induction in macrophages, and inhibited Interleukin-4 (IL-4) expression in nonadherent peritoneal exudate cells. Furthermore, neutralization of endogenous IL-4 by anti-IL-4 mAb enhanced the HSP65 induction in macrophages. These findings suggest that NKT cells, but not NK cells, negatively regulate the protective immunity against T. gondii infection possibly by producing IL-4 and suppressing HSP65 induction.

• Authors: Y Nakano, H Hisaeda, T Sakai, M Zhang, Y Maekawa, T Zhang, K Himeno
• Journal: The journal of medical investigation : JMI (J Med Invest) Vol. 48 Issue 1-2 Pg. 73-80 (Feb 2001) ISSN: 1343-1420 [Print] Japan
• PMID: 11286020 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Bacterial Proteins
• Chaperonin 60
• RNA, Messenger
• Receptors, Antigen, T-Cell, gamma-delta
• Receptors, Interleukin-2
• heat-shock protein 65, Mycobacterium
• Interleukin-4
• G(M1) Ganglioside
• asialo GM1 ganglioside
• Interferon-gamma
• Chaperonins

Topics

• Animals
• Antibody Specificity
• Bacterial Proteins
• Chaperonin 60
• Chaperonins (immunology)
• Female
• G(M1) Ganglioside (immunology)
• Gene Expression
• Immunity, Innate (immunology)
• Interferon-gamma (genetics)
• Interleukin-4 (genetics, immunology)
• Killer Cells, Natural (immunology)
• Lymphocyte Depletion
• Macrophages, Peritoneal (immunology)
• Mice
• Mice, Inbred BALB C
• Neutralization Tests
• Peritoneal Cavity
• RNA, Messenger
• Receptors, Antigen, T-Cell, gamma-delta (immunology)
• Receptors, Interleukin-2 (immunology)
• T-Lymphocytes (immunology)
• Toxoplasma (immunology)
• Toxoplasmosis (immunology)