Cell-surface bound pertussis toxin induces polyclonal T cell responses with high levels of interferon-gamma in the absence of interleukin-12.

Journal article

Pertussis toxin (PTx), an exotoxin produced by Bordetella pertussis, has long been used as a mucosal adjuvant. We examined the T cell stimulatory properties of PTx in order to dissect its mechanisms of adjuvanticity. PTx or the B-oligomer of PTx (PTxB) failed to activate purified murine CD4+ or CD8+ T cells, as measured by a lack of proliferation or expression of early T cell activation markers. However, these T cells proliferated extensively in response to the toxin in the presence of syngeneic DC, and proliferation was accompanied by a high level of IFN-gamma production in the absence of IL-12. Interestingly, such responses were independent of signals mediated by MHC-TCR interaction. Both PTx and PTxB were found to bind stably to the surface of DC, and increased the adherence of DC to surrounding cells. These data suggest that polyclonal T cell responses mediated by the toxin are likely to be caused by the toxin bound on the surface of APC, either cross-linking cell surface molecules on T cells, or directly stimulating T cells together with the co-stimulatory molecules expressed on APC. B. pertussis may use this toxin as a mechanism to evade a specific immune response.

Authors: Wakatsuki, A; Borrow, P; Rigley, K; Beverley, P

• Publication status: Published
• Journal: European journal of immunology
• Volume: 33
• Issue: 7
• Pages: 1859-1868
• Publication date: 2003-07-01
• DOI: 10.1002/eji.200323675
• EISSN: 1521-4141
• ISSN: 0014-2980
• Language: English
• Keywords: Interferon-gamma; Cell Division; Interleukin-12; Dendritic Cells; Antigen-Presenting Cells; Pertussis Toxin; Mice; Animals; T-Lymphocytes