Aptamer-Based Antibacterial and Antiviral Therapy against Infectious Diseases

Abstract

Nucleic acid aptamers are single-stranded DNA or RNA molecules selected in vitro that can bind to a broad range of targets with high affinity and specificity. As promising alternatives to conventional anti-infective agents, aptamers have gradually revealed their potential in the combat against infectious diseases. This article provides an overview on the state-of-art of aptamer-based antibacterial and antiviral therapeutic strategies. Diverse aptamers targeting pathogen-related components or whole pathogenic cells are summarized according to the species of microorganisms. These aptamers exhibited remarkable in vitro and/or in vivo inhibitory effect for pathogenic invasion, enzymatic activities, or viral replication, even for some highly drug-resistant strains and biofilms. Aptamer-mediated drug delivery and controlled drug release strategies are also included herein. Critical technical barriers of therapeutic aptamers are briefly discussed, followed by some future perspectives for their implementation into clinical utility.

An Explorative Review on Advanced Approaches to Overcome Bacterial Resistance by Curbing Bacterial Biofilm Formation

“… 269 , 270 Though these particles excel due to their low toxicity and high drug entrapment ability, their use is challenged by their low target specificity, instability, and short half-life in serum. 267 , 271 To overcome these disadvantages, scientists functionalized these particles using ligands (eg, aptamers (Aptamosomes) 272 , 273 or polyethylene glycols (PEGylation) 271 , 274 ). In detail, aptamosomes are liposomes conjugated with aptamers—a short portion of RNA or DNA designed to improve specificity and affinity.…”

“…overcome these disadvantages, scientists functionalized these particles using ligands (eg, aptamers (Aptamosomes) 272,273 or polyethylene glycols (PEGylation) 271,274 ). In detail, aptamosomes are liposomes conjugated with aptamers-a short portion of RNA or DNA designed to improve specificity and affinity.…”

Aptasensors for the detection of infectious pathogens: design strategies and point-of-care testing

“…Essentially, SELEX is a technique that simulates natural evolution in vitro to screen the "fittest" aptamers from a random oligonucleotide library. A typical SELEX process involves three main steps: incubation, separation, and amplification [21]. Target molecules are mixed and incubated with an oligonucleotide library containing 10 12 -10 16 DNA or RNA single strands [22].…”

“…The implementation of these aptamers for the diagnosis and treatment of infectious diseases have been vastly studied [17,[34][35][36]. Recently, we published a perspective review article on the state-of-the-art of aptamer-based therapeutic strategies for the treatment of common infectious diseases [21]. Aptamers against membrane-fusion-related proteins, key enzymes, and whole microbial cells could function as effective inhibitors or drug delivery vehicles to inhibit infection.…”

“…The binding is also highly sensitive to exterior interferences such as pH, temperature, and species of buffer. Sometimes the high binding affinity cannot be reproduced without a standard protocol; (iii) most of the in vitro SELEX were carried out in saline buffer or cell culture medium, and those selected aptamers may not retain their high affinity and specificity toward pathogens in their natural forms, concerning the complexity of real sample analysis and diverse interfering factors [21]; (iv) DNA/RNA aptamers, especially unmodified ones, are intrinsically susceptible to nuclease degradation. Their metabolic instability and other pharmacokinetic problems such as rapid renal filtration may have adverse effect on their binding performance in physiological environment [191].…”