Oligonucleotide probes for imaging and diagnosis of bacterial infections

Abstract

The rise of infectious diseases as a public health concern has necessitated the development of rapid and precise diagnostic methods. Imaging techniques like nuclear and optical imaging provide the ability to diagnose infectious diseases within the body, eliminating delays caused by sampling and pre-enrichments of clinical samples and offering spatial information that can aid in a more informed diagnosis. Traditional molecular probes are typically created to image infected tissue without accurately identifying the pathogen. In contrast, oligonucleotides can be tailored to target specific RNA sequences, allowing for the identification of pathogens, and even generating antibiotic susceptibility profiles by focusing on drug resistance genes. Despite the benefits that nucleic acid mimics (NAMs) have provided in terms of stabilizing oligonucleotides, the inadequate delivery of these relatively large molecules into the cytoplasm of bacteria remains a challenge for widespread use of this technology. This review summarizes the key advancements in the field of oligonucleotide probes for in vivo imaging, highlighting the most promising delivery systems described in the literature for developing optical imaging through in vivo hybridization.

Graphical Abstract

Keywords:

• Optical imaging
• bacterial infections
• nucleic acid mimics (NAMs)
• oligonucleotide probes
• nanocarriers

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was financially supported by (i) [LA/P/0045/2020] (ALiCE), [UIDB/00511/2020 and UIDP/00511/2020] (LEPABE), funded by national funds through FCT/MCTES (PIDDAC); (ii) Projects [POCI-01-0145-FEDER-016678] (Coded-FISH), [POCI-01-0145-FEDER-030431] (CLASInVivo) and [POCI-01-0145-FEDER-031011] (µFISH), funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/MCTES; (iii) Project 2SMART - engineered Smart materials for Smart citizens, with reference [NORTE-01-0145-FEDER-000054], supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); (iv) project DELNAM - European Union’s Horizon 2020 research and innovation programme under grant agreement [No 810685]; (v) Project [EXPL/NAN-MAT/0209/2021] supported by FCT—Fundação para a Ciência e a Tecnologia; (vi) FCT supported J.A.L under the Scientific Employment Stimulus - Institutional Call – [CEECINST/00049/2018] and; (vii) PhD fellowship developed under the doctoral program in Chemical and Biological Engineering (PDEQB) [NORTE-08-5369-FSE-000028], co-financed by the Northern Regional Operational Program (NORTE 2020) through Portugal 2020 and the European Social Fund (ESF).