Adherence of Candida albicans to silicone is promoted by the human salivary protein SPLUNC2/PSP/BPIFA2. (8th February 2014)

• Record Type: Journal Article
• Authors: Holmes, A.R.; Rodrigues, E.; van der, P.; Lyons, K.M.; Haigh, B.J.; Wheeler, T.T.; Dawes, P.J.D.; Cannon, R.D.
• Is Part Of: Molecular oral microbiology. Volume 29:Number 2(2014)
• Page Start: 90
• Page End: 98
• Publication Date: 2014-02-08
• Subjects: Mouth -- Microbiology -- Periodicals; Respiratory infections -- Microbiology -- Periodicals; Mouth -- Diseases -- Immunological aspects -- Periodicals; 617.522
• DOI: 10.1111/omi.12048
• Languages: English
• ISSNs: 2041-1006

Abstract

<abstract abstract-type="main" id="omi12048-abs-0001"> <title>Summary</title> <p>Interactions between <italic>Candida albicans</italic>, saliva and saliva‐coated oral surfaces are initial events in the colonization of the oral cavity by this commensal yeast, which can cause oral diseases such as candidiasis and denture stomatitis. <italic>Candida albicans</italic> also colonizes silicone voice prostheses, and the microbial biofilm formed can impair valve function, necessitating frequent prosthesis replacement. We have previously shown that saliva promoted binding of <italic>C. albicans</italic> cells to silicone <italic>in vitro</italic>, and that the selective binding of specific salivary proteins to voice prosthesis silicone mediated attachment of <italic>C. albicans</italic> cells. The <italic>C. albicans</italic> cells adhered to a polypeptide (or polypeptides) of ~36 kDa eluted from saliva‐treated silicone. We show here that a protein of similar size was identified in replicate blots of the eluate from saliva‐treated silicone when the blots were probed with antibodies to human SPLUNC2, a salivary protein with reported microbial agglutination properties. In addition, SPLUNC2 was depleted from saliva that had been incubated with silicone coupons. To determine whether SPLUNC2 is a yeast‐binding protein, SPLUNC2 cDNA was expressed in <italic>Escherichia coli</italic>. Purified recombinant His‐tagged protein (SPLUNC2r) bound to silicone as demonstrated by immunoblot analysis of an eluate from SPLUNC2r‐treated silicone coupons and <sup>35</sup>S‐radiolabelled <italic>C. albicans</italic> cells adhered in a dose‐dependent manner to SPLUNC2r‐coated silicone. We conclude that SPLUNC2 binds to silicone and acts as a receptor for <italic>C. albicans</italic> adherence to, and subsequent colonization of, voice prosthesis silicone.</p> </abstract>