American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Oct 2023
Randomized Controlled TrialA Randomised Controlled Trial of Nasal Immunisation with Live Virulence Attenuated Streptococcus pneumoniae Strains Using Human Infection Challenge.
Rationale: Pneumococcal pneumonia remains a global health problem. Pneumococcal colonization increases local and systemic protective immunity, suggesting that nasal administration of live attenuated Streptococcus pneumoniae (Spn) strains could help prevent infections. Objectives: We used a controlled human infection model to investigate whether nasopharyngeal colonization with attenuated S. pneumoniae strains protected against recolonization with wild-type (WT) Spn (SpnWT). ⋯ Participants given SpnWT or SpnA1 in Stage I were partially protected against homologous challenge with SpnWT (29% and 30% recolonization rates, respectively) at stage II, whereas those exposed to SpnA3 achieved a recolonization rate similar to that in the control group (50% vs. 47%, respectively). Conclusions: Nasal colonization with genetically modified live attenuated Spn was safe and induced protection against recolonization, suggesting that nasal administration of live attenuated Spn could be an effective strategy for preventing pneumococcal infections. Clinical trial registered with the ISRCTN registry (ISRCTN22467293).
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Am. J. Respir. Crit. Care Med. · Oct 2023
Restoration of Foxp3+ Regulatory T Cells by HDAC-dependent Epigenetic Modulation Plays a Pivotal Role in Resolving Pulmonary Arterial Hypertension Pathology.
Rationale: Immune dysregulation is a common feature of pulmonary arterial hypertension (PAH). Histone deacetylase (HDAC)-dependent transcriptional reprogramming epigenetically modulates immune homeostasis and is a novel disease-oriented approach in modern times. Objectives: To identify a novel functional link between HDAC and regulatory T cells (Tregs) in PAH, aiming to establish disease-modified biomarkers and therapeutic targets. ⋯ Furthermore, SAHA inhibited endothelial cytokine/chemokine release upon stimulation and subsequent immune chemotaxis. Conclusions: Our results indicated HDAC aberration was associated with Foxp3+ Treg deficiency and demonstrated an epigenetic-mediated mechanism underlying immune dysfunction in PAH. Restoration of Foxp3+ Tregs by HDAC inhibitors is a promising approach to resolve pulmonary vascular pathology, highlighting the potential benefit of developing epigenetic therapies for PAH.
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Am. J. Respir. Crit. Care Med. · Oct 2023
A Multicenter, Single-arm, Prospective Trial Assessing the Diagnostic Yield of Electromagnetic Bronchoscopic and Transthoracic Navigation for Peripheral Pulmonary Nodules.
Rationale: Strict adherence to procedural protocols and diagnostic definitions is critical to understand the efficacy of new technologies. Electromagnetic navigational bronchoscopy (ENB) for lung nodule biopsy has been used for decades without a solid understanding of its efficacy, but offers the opportunity for simultaneous tissue acquisition via electromagnetic navigational transthoracic biopsy (EMN-TTNA) and staging via endobronchial ultrasound (EBUS). Objective: To evaluate the diagnostic yield of EBUS, ENB, and EMN-TTNA during a single procedure using a strict a priori definition of diagnostic yield with central pathology adjudication. ⋯ Conclusions: The diagnostic yield for ENB is 49%, which increases to 59% with the addition of same-day CT, EBUS, and EMN-TTNA, lower than in prior reports in the literature. The high complication rate and low diagnostic yield of EMN-TTNA does not support its routine use. Clinical trial registered with www.clinicaltrials.gov (NCT03338049).