Interferon-gamma-activated macrophages infected with Burkholderia cenocepacia process and present bacterial antigens to T-cells by class I and II major histocompatibility complex molecules

Mucous Permeable Nanoparticle for Inducing Cuproptosis-Like Death In Broad-Spectrum Bacteria for Nebulized Treatment of Acute Pneumonia

The emergence of antibiotic-resistant bacteria has exacerbated the challenge of treating infectious diseases. Quorum sensing (QS), a bacterial communication system regulating virulence and biofilm formation, presents a target for novel therapies. Cuproptosis death is a innovation mode of death, however, this effect may be partially inhibited by glutathione (GSH). Buthionine sulfoximine (BSO) is responsible for GSH biosynthesis and has been identified as a potential promoter of cuproptosis death. Here, Cu2O-BSO NPs with lung adhesion and mucus penetration ability are synthesized by incorporating BSO onto Cu2O, and modifying it with DOPA and PEG. Cu2O-BSO NPs demonstrated a broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria, making it a viable treatment option for MRSA-induced acute pneumonia. Specifically, Cu2O-BSO NPs can synergistically enhance bacterial cuproptosis-like death, hinder the QS system, eradicate biofilms, reduce the virulence of strains, stimulate the chemotaxis and phagocytosis of macrophages, and ultimately improve in mice with severe pneumonia. This research demonstrated the potential of Cu2O-BSO NPs for a wide-ranging antibacterial alternative, providing promise for addressing microbial resistance and combatting biofilm formation. Additionally, it established a target and theoretical foundation for the clinical treatment of numerous challenging cases of acute drug-resistant bacteria.

Bacterial Subversion of Autophagy in Cystic Fibrosis

Cystic fibrosis (CF) is a genetic disease affecting more than 70,000 people worldwide. It is caused by a mutation in the cftr gene, a chloride ion transporter localized in the plasma membrane of lung epithelial cells and other organs. The loss of CFTR function alters chloride, bicarbonate, and water transport through the plasma membrane, promoting the production of a thick and sticky mucus in which bacteria including Pseudomonas aeruginosa and Burkholderia cenocepacia can produce chronic infections that eventually decrease the lung function and increase the risk of mortality. Autophagy is a well-conserved lysosomal degradation pathway that mediates pathogen clearance and plays an important role in the control of bacterial infections. In this mini-review, we describe the principal strategies used by P. aeruginosa and B. cenocepacia to survive and avoid microbicidal mechanisms within the autophagic pathway leading to the establishment of chronic inflammatory immune responses that gradually compromise the lung function and the life of CF patients.

The intracellular phase of extracellular respiratory tract bacterial pathogens and its role on pathogen-host interactions during infection

PURPOSE OF REVIEW

An initial intracellular phase of usually extracellular bacterial pathogens displays an important strategy to hide from the host's immune system and antibiotics therapy. It helps the bacteria, including bacterial pathogens of airway diseases, to persist and eventually switch to a typical extracellular infection. Several infectious diseases of the lung are life-threatening and their control is impeded by intracellular persistence of pathogens. Thus, molecular adaptations of the pathogens to this niche but also the host's response and potential targets to interfere are of relevance. Here we discuss examples of historically considered extracellular pathogens of the respiratory airway where the intracellular survival and proliferation is well documented, including infections by Staphylococcus aureus, Bordetella pertussis, Haemophilus influenzae, Pseudomonas aeruginosa, and others.

RECENT FINDINGS

Current studies focus on bacterial factors contributing to adhesion, iron acquisition, and intracellular survival as well as ways to target them for combatting the bacterial infections.

SUMMARY

The investigation of common and specific mechanisms of pathogenesis and persistence of these bacteria in the host may contribute to future investigations and identifications of relevant factors and/or bacterial mechanisms to be blocked to treat or improve prevention strategies.