The assay that defines desmosome hyper-adhesion

In a recent Letter to the Editor it was suggested that desmoplakin (DP) regulates desmosome hyper-adhesion (Hobbs and Green, 2011). The term hyper-adhesion refers to the strong, calcium-independent adhesive state adopted by desmosomes in tissues, including the epidermis (Garrod et al., 2005; Wallis et al., 2000). This contrasts with a weaker adhesive state adopted by desmosomes on initial formation in tissue culture, in wound edge epithelium and in early embryonic development (Garrod, 2010; Garrod et al., 2005; Kimura et al., 2007; Thomason et al., 2012; Wallis et al., 2000). Desmosomal hyper-adhesion appears to be important for the integrity of the epidermis as indicated by its role in wound healing and pemphigus (Cirillo et al., 2010; Garrod et al., 2005; Thomason et al., 2012).In order to show that desmosomes are hyper-adhesive a specific assay for calcium independence is required.