IgA subclass antibodies have been reported in a few studies in patients with CAC. IgA antibodies and IgA1 antibodies were increased in comparison with the controls (Ivanyi and Ivanyi, 1990). However, it is possible that some of this IgA1 antibody might have been derived from inflammation in the oral cavity itself. However, Coogan et al. (1994) showed that in HIV infection IgA1 and IgA2 subclass antibodies against Candida were raised in both whole and parotid saliva compared with controls. This suggested that patients with HIV were not significantly immunocompromised when compared with controls and that Candida infection could induce subclass responses in these patients. More recently, Wellington et al. (2003) have demonstrated enhanced phagocytosis of Candida by polymorphonu-clear leucocytes (PMNs) mediated by a recombinant human antibody—single chain. This demonstrates another mechanism that may be operative in vivo, especially considering that PMNs are a major cell type around invading hyphae. It might be expected that if this mechanism was operative in vivo that it would be active against the CHC rather than the CAC type of oral candidiasis.
An interesting development is the derivation of peptides from single chain recombinant and idiotypic antibodies, which retain microbicidal activity (Polonelli et al., 2003). This killer peptide has been used in vivo where in a rat model of vaginal candidiasis local post-challenge administration of KP was efficacious in rapidly ablating infections. It probably acts through its interaction with the P-glucan KT receptor on C. albicans but it has not yet been reported as being used in an oral infection. The concept of modelling in vivo activity by using monoclonal antibodies was studied further by Moragues et al. (2003) where a monoclonal raised against the main target of salivary secretory IgA in the cell wall of the C. albicans was demonstrated to show three separate anti-C. albicans activities: (1) inhibition of adherence to Hep2 cells, (2) inhibition of germination, and (3) direct candicidal activity.
Was this article helpful?