Alpha-Gal Bound Aptamer and Vancomycin Synergistically Reduce Staphylococcus aureus Infection In Vivo

Harnessing endogenous anti-glycan antibodies using a novel, bifunctional immunotherapy to treat gram-negative bacterial infections

The current array of traditional antibacterial agents targeting Gram-negative infections are failing to meet the clinical need. Here we present a novel, bifunctional immunotherapy (CTX-09) with the ability to harness endogenous anti-galactose-alpha-1,3-galactosyl-beta-1,4-N-acetyl-glucosamine (anti-αGal) antibodies to drive immune-mediated clearance of Gram-negative bacteria. In addition, CTX-09 has direct-acting broad-spectrum bactericidal activity equivalent to colistin and meropenem against 1952 Gram-negative clinical isolates. In vitro, CTX-09 demonstrated immune-mediated efficacy through recruitment of anti-αGal antibodies and engagement of antibody effector mechanisms that enhanced bacterial clearance at sub-bactericidal concentrations. In vivo, at sub-bactericidal doses, CTX-09 demonstrated anti-αGal antibody driven clearance of susceptible and multidrug-resistant (MDR) strains. In the presence of anti-αGal antibody, bacterial burden was reduced by >99.9% (3-log10) in neutropenic mouse thigh and pneumonia infection models. This data suggest that CTX-09 or other antibody-recruiting molecules have potential to address the urgent clinical need of patients with gram-negative infections using a novel immunotherapeutic mechanism.

Aptamer selection via versatile microfluidic platforms and their diverse applications

Aptamers are synthetic oligonucleotides that bind with high affinity and specificity to various targets, making them invaluable for diagnostics, therapeutics, and biosensing. Microfluidic platforms can improve the efficiency and scalability of aptamer selection, especially through advancements in systematic evolution of ligands by exponential enrichment (SELEX) methods. Microfluidic SELEX methods are less time-consuming and labor-intensive and include critical steps like library preparation, binding, partitioning, and amplification. This review examines the contributions of microfluidic technology to SELEX-based aptamer identification, with alternative methods like conditional SELEX, in vivo-like SELEX and Non-SELEX for selecting aptamers and also discusses critical SELEX steps over the past decade. This work also examined the integrated microfluidic systems for SELEX, highlighting innovations such as conditional SELEX and in vivo-like SELEX. These advancements provide potential solutions to existing challenges in aptamer selection using conventional SELEX, especially concerning biological samples. A trend toward non-SELEX methods was also reviewed and discussed, wherein nucleic acid amplification was eliminated to improve aptamer selection. Microfluidic platforms have demonstrated versatility not only in aptamer selection but also in various detection applications; they allow for precise control of liquid flow and have been essential in the advancement of therapeutic aptamers, facilitating accurate screening, enhancing drug delivery systems, and enabling targeted therapeutic interventions. Although advances in microfluidic technology are expected to enhance aptamer-based diagnostics, therapeutics, and biosensing, challenges still persist, especially in up-scaling microfluidic systems for various clinical applications. The advantages and limitations of integrating microfluidic platforms with aptamer development are further addressed, emphasizing areas for future research. We also present a perspective on the future of microfluidic systems and aptamer technologies, highlighting their increasing significance in healthcare and diagnostics.

Aptamers: precision tools for diagnosing and treating infectious diseases

Infectious diseases represent a significant global health challenge, with bacteria, fungi, viruses, and parasitic protozoa being significant causative agents. The shared symptoms among diseases and the emergence of new pathogen variations make diagnosis and treatment complex. Conventional diagnostic methods are laborious and intricate, underscoring the need for rapid, accurate techniques. Aptamer-based technologies offer a promising solution, as they are cost-effective, sensitive, specific, and convenient for molecular disease diagnosis. Aptamers, which are single-stranded RNA or DNA sequences, serve as nucleotide equivalents of monoclonal antibodies, displaying high specificity and affinity for target molecules. They are structurally robust, allowing for long-term storage without substantial activity loss. Aptamers find applications in diverse fields such as drug screening, material science, and environmental monitoring. In biomedicine, they are extensively studied for biomarker detection, diagnostics, imaging, and targeted therapy. This comprehensive review focuses on the utility of aptamers in managing infectious diseases, particularly in the realms of diagnostics and therapeutics.

Advancements and Challenges in Aptamer-Based Therapeutics and Diagnostics Across Diverse Medical Domains: A Comprehensive Review

Aptamers, which are single-stranded DNA or RNA molecules, are increasingly recognized as important tools in diagnostics and therapeutics across various medical disciplines such as oncology, respiratory diseases, and neurological disorders. This review provides a comprehensive evaluation of the recent progress and obstacles encountered in the field of aptamer-based applications. Aptamers have shown promise in oncology for early cancer detection and targeted drug delivery, effectively reducing off-target effects. They also hold potential for significantly impacting the management of respiratory conditions such as asthma and Chronic Obstructive Pulmonary Disease (COPD) by selectively targeting cytokines and regulating the inflammatory response. In the realm of neurological disorders, aptamers offer novel methods by influencing the gut-brain axis and proposing potential approaches for early detection and specific therapy. Despite these notable benefits, persistent challenges remain in areas such as molecular stability, delivery mechanisms, and economic viability. This review offers a comprehensive overview of aptamer-based diagnostics and therapeutics while exploring potential avenues for future research.

Aptamer-based therapy for fighting biofilm-associated infections

Biofilms are key players in the pathogenesis of most of chronic infections associated with host tissue or fluids and indwelling medical devices. These chronic infections are hard to be treated due to the increased biofilms tolerance towards antibiotics in comparison to planktonic (or free living) cells. Despite the advanced understanding of their formation and physiology, biofilms continue to be a challenge and there is no standardized therapeutic approach in clinical practice to eradicate them. Aptamers offer distinctive properties, including excellent affinity, selectivity, stability, making them valuable tools for therapeutic purposes. This review explores the flexibility and designability of aptamers as antibiofilm drugs but, importantly, as targeting tools for diverse drug and delivery systems. It highlights specific examples of application of aptamers in biofilms of diverse species according to different modes of action including inhibition of motility and adhesion, blocking of quorum sensing molecules, and dispersal of biofilm-cells to planktonic state. Moreover, it discusses the limitations and challenges that impaired an increased success of the use of aptamers on biofilm management, as well as the opportunities related to aptamers modifications that can significantly expand their applicability on the biofilm field.