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Title: A Photoacoustic‐Fluorescent Imaging Probe for Proteolytic Gingipains Expressed by Porphyromonas gingivalis
Abstract

Porphyromonas gingivalisis a keystone pathogen in periodontal disease. We herein report a dual‐modal fluorescent and photoacoustic imaging probe for the detection of gingipain proteases secreted byP. gingivalis. Upon proteolytic cleavage by Arg‐specific gingipain (RgpB), five‐fold photoacoustic enhancement and >100‐fold fluorescence activation was measured with detection limits of 1.1 nM RgpB and 5.0E4 CFU mL−1bacteria in vitro. RgpB activity was imaged in porcine jaws with low‐nanomolar sensitivity. Diagnostic efficacy was evaluated in gingival crevicular fluid samples from subjects with and without periodontal disease, wherein activation was correlated to qPCR‐based detection ofP. gingivalis(Pearson'sr=0.71). Finally, photoacoustic imaging of RgpB‐cleaved probe was achieved in murine brains ex vivo, with relevance and potential utility for disease models of general infection byP. gingivalis, motivated by the recent biological link between gingipain and Alzheimer's disease.

 
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NSF-PAR ID:
10445239
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
134
Issue:
30
ISSN:
0044-8249
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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