The wide diversity of microbiota at the genera and species levels across sites and individuals is related to various causes and the observed differences between individuals. Efforts are underway to further understand and characterize the human-associated microbiota and its microbiome. Using 16S rDNA as a genetic marker for bacterial identification improved the detection and profiling of qualitative and quantitative changes within a bacterial population. In this light, this review provides a comprehensive overview of the basic concepts and clinical applications of the respiratory microbiome, alongside an in-depth explanation of the molecular targets and the potential relationship between the respiratory microbiome and respiratory disease pathogenesis. The paucity of robust evidence supporting the correlation between the respiratory microbiome and disease pathogenesis is currently the main challenge for not considering the microbiome as a novel druggable target for therapeutic intervention. Therefore, further studies are needed, especially prospective studies, to identify other drivers of microbiome diversity and to better understand the changes in the lung microbiome along with the potential association with disease and medications. Thus, finding a therapeutic target and unfolding its clinical significance would be crucial.

The immediate aim of this study was to comparatively examine the bacterial respiratory microbiome of patients in a stable state and during an exacerbation of asthma–COPD (chronic obstructive pulmonary disease) overlap (ACO). This prospective observational study took place in Jordan between 1 September 2021 and 30 April 2022. Sputum samples from patients with recognized ACO were acquired within 48 h of the exacerbation onset and again at 3 weeks following the exacerbation. The next-generation sequencing Illumina MiSeq was employed and uncovered significantly high bacterial diversity in the sputa. The results showed a significant decrease in the taxonomic richness in the sputum samples collected during the exacerbation episodes compared with those collected from patients in a stable state (p = 0.008), with an increase in the taxonomic evenness (p < 0.005). This change in the composition of the airway bacterial community suggests that the replacement of a significant portion of the airway microbiome with certain microorganisms may play a role in the decrease in microbial diversity observed during an ACO exacerbation. Greater knowledge of this link could allow for a more focused administration of antibiotics, especially during exacerbations, improving clinical efficacy and patient outcomes.

This research aimed to evaluate the effects of high-dose cholecalciferol (VD3) supplements (50,000 IU/week) on selected circulating cytokines associated with cytokine storms in adults with vitamin D deficiency. This clinical trial, based in Jordan, included 50 participants receiving vitamin D3 supplements (50,000 IU/week) for 8 weeks; the exact number was assigned to the control group. Interleukin-6 (IL-6), interleukin-1β (IL-1β), interleukin-10 (IL-10), tumor necrotic factor-α (TNF-α), and leptin were measured in serum at baseline and 10 weeks (wash out: 2 weeks). Our results revealed that vitamin D3 supplementation significantly increased the serum levels of 25OHD, IL-6, IL-10, IL-1β, and leptin compared with baseline. In contrast, the serum level of TNF-α insignificantly increased in the group receiving vitamin D3 supplementation. Although the observations of this trial may refer to a potential negative effect of VD3 supplementation during cytokine storms, further trials are required to clarify the potential benefits of VD3 supplement during cytokine storms.

This research aims to determine acute bronchiolitis’ causative virus(es) and establish a viable protocol to classify the Human Rhinovirus (HRV) species. During 2021–2022, we included children 1–24 months of age with acute bronchiolitis at risk for asthma. The nasopharyngeal samples were taken and subjected to a quantitative polymerase chain reaction (qPCR) in a viral panel. For HRV-positive samples, a high-throughput assay was applied, directing the VP4/VP2 and VP3/VP1 regions to confirm species. BLAST searching, phylogenetic analysis, and sequence divergence took place to identify the degree to which these regions were appropriate for identifying and differentiating HRV. HRV ranked second, following RSV, as the etiology of acute bronchiolitis in children. The conclusion of the investigation of all available data in this study distributed sequences into 7 HRV-A, 1 HRV-B, and 7 HRV-C types based on the VP4/VP2 and VP3/VP1 sequences. The nucleotide divergence between the clinical samples and the corresponding reference strains was lower in the VP4/VP2 region than in the VP3/VP1 region. The results demonstrated the potential utility of the VP4/VP2 region and the VP3/VP1 region for differentiating HRV genotypes. Confirmatory outcomes were yielded, indicating how nested and semi-nested PCR can establish practical ways to facilitate HRV sequencing and genotyping.