Toxins Produced by Clostridium Species

Other toxins produced by Clostridium species have been shown to have immunomodulatory activities. The Type D toxin produced by Clostridium botulism inhibits the production of TNF-a by LPS stimulated human monocytes. Additionally, the Clostridium perfingens delta toxin has been shown to be cytotoxic to rabbit macrophages, but not to thymocytes.  

PT induces the maturation of monocyte-derived (MD)DC, resulting in the up-r ulation of CD80, CD86, CD83 and MHC Class and enhances the production of IL-12, TNF-a, IL-8 

Both PT and CyaA have been used to deliver viral and tumour peptides into cells in order to prime CTL responses. PT mediated delivery of a HIV gpl 20 into the MHC Class I pathway was able to induce the generation of CTL responses in vitro and in vivo. CyaA mediated peptide delivery can result in the stimulation of both the MHC Class I and II pathways, resulting in the activation of both CTL and CD4 T-cell responses. The ability of CyaA to target antigen 

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