Exploring Host–Commensal Interactions in the Respiratory Tract

Abstract

Commensal microbes are currently in the limelight in biomedical research because they play an important role in health and disease. Humans harbor an enormous diversity of commensals in various parts of the body, including the gastrointestinal and respiratory tracts. Advancement in metagenomic and other omic approaches, and development of suitable animal models have provided an unprecedented appreciation into the diversity of commensals, and the intricacies of their intimate communication with the host immune system. Most studies have focused on the host–commensal interaction in the gut, while less is known on this relationship in other sites of the body, such as the respiratory tract. In this article, we review emerging data from human and animal studies on the host responses to respiratory commensals, immune cross-reactivity between commensals and pathogens, and use of commensals as a vaccine delivery system. A better understanding of the delicate interplay between commensals and host may aid in efforts to develop effective vaccines and therapeutics.

Changes in upper airways microbiota in ventilator-associated pneumonia

“…To define the characteristic upper airway microbiota and its changes during MV, we evaluated the prevalence of each bacteria genera. The analysis over time confirmed the principal role of Streptococcus as commensal bacteria of the respiratory tract microbiota, confirming previous identification of positive association with healthy lungs [38,39] and possible negative association with the development of lung disease [40]. Furthermore, some genera (Actinomyces, Rothia, Granulicatella and Streptococcus) are more represented during intubation than during ventilation.…”

https://researchopenworld.com/does-a-commensal-relationship-exist-between-coronaviruses-and-some-human-populations/#

“…While it is not surprising that some human populations have adapted to the presence of certain pathogens by becoming more resistant, the population in this case has become less resistant, as if it actually benefits from infection by respiratory viruses. Some immunologists have suggested that such viruses boost the immune response of lung tissue and thereby prevent more serious pulmonary diseases, like tuberculosis, pneumonia, and pneumonic plague [8]. This preventive effect has been shown with other viruses.…”

Overview of the rules of the microbial engagement in the gut microbiome: a step towards microbiome therapeutics

“…Therefore, maternal genetics, environment and diet during pregnancy and after birth influence the bacterial colonization in infants (Kim et al 2020). As during colonization, microbes face a challenging and dynamic Table 1 Role of the human gut microbes in human health Benefits to human health Enterotypes involved environment of the human gut, they have to establish a commensal interaction to stabilize as a gut microbiome (Shekhar et al 2017). Various studies have successfully enlisted microbial genetic and physiological traits to pass through these selective channels to ensure itself as a member of the human gut microbiome (Fig.…”

“…As during colonization, microbes face a challenging and dynamic environment of the human gut, they have to establish a commensal interaction to stabilize as a gut microbiome (Shekhar et al . 2017). Various studies have successfully enlisted microbial genetic and physiological traits to pass through these selective channels to ensure itself as a member of the human gut microbiome (Fig.…”