Weekly Respiratory Research Analysis
This week’s respiratory literature was dominated by real-world genomic surveillance and mechanistic studies with immediate translational implications. Large-scale sequencing in France detected emergent nirsevimab-resistant RSV‑B variants in infant breakthrough infections, prompting calls for routine resistance monitoring. Structural and preclinical work (EV‑D68 VLP antibody mapping; a SIRT5–FDX1 cuproptosis axis in lung adenocarcinoma) defined actionable antigenic vulnerabilities and a novel tum
Summary
This week’s respiratory literature was dominated by real-world genomic surveillance and mechanistic studies with immediate translational implications. Large-scale sequencing in France detected emergent nirsevimab-resistant RSV‑B variants in infant breakthrough infections, prompting calls for routine resistance monitoring. Structural and preclinical work (EV‑D68 VLP antibody mapping; a SIRT5–FDX1 cuproptosis axis in lung adenocarcinoma) defined actionable antigenic vulnerabilities and a novel tumor resistance mechanism that nominate vaccine/antibody designs and combinatorial therapeutic strategies. These findings push surveillance, vaccine design, and targeted therapy toward rapid clinical and public‑health application.
Selected Articles
1. Real-world emergence of nirsevimab resistance in breakthrough infections with respiratory syncytial virus-B: a multicentre observational study in France.
Multicentre genomic surveillance of infant RSV infections identified resistance‑associated F‑protein substitutions concentrated in RSV‑B breakthrough cases after nirsevimab prophylaxis. Full‑genome sequencing (858 high‑quality genomes) plus neutralization assays showed ~12.5% of RSV‑B breakthroughs carried mutations (e.g., at N208 and other Φ‑site residues) that reduced nirsevimab susceptibility; such variants were not seen in nirsevimab‑naive infants and persisted up to ~1 year post‑prophylaxis.
Impact: First large real‑world demonstration that nirsevimab resistance arises in RSV‑B, integrating genomic and phenotypic data and directly affecting infant prophylaxis strategies and public‑health surveillance requirements.
Clinical Implications: Implement routine genomic surveillance of RSV during monoclonal rollout, prepare contingency plans (alternate prophylaxis, timing adjustments, combination approaches), and prioritize phenotypic neutralization testing when resistance‑associated substitutions are detected.
Key Findings
- Resistance‑associated substitutions identified in 23/184 (12.5%) RSV‑B breakthrough cases versus 2/195 (1.0%) RSV‑A.
- Novel F‑protein mutations (e.g., N208D/I/K/S/Y and other Φ‑site changes) conferred reduced nirsevimab neutralization in vitro.
- No resistant viruses detected among nirsevimab‑naive infants; resistant RSV‑B observed up to ~1 year post‑prophylaxis.
2. Neutralizing antibodies elicited in nonhuman primates by an enterovirus D68 virus-like particle vaccine target receptor binding sites.
Nonhuman primate immunization with EV‑D68 VLPs yielded potent neutralizing monoclonal antibodies that bind overlapping epitopes near the VP1 fivefold axis bridging sialic‑acid and MFS6 receptor sites. Cryo‑EM structural mapping and mechanistic assays showed these mAbs disrupt multiple viral life‑cycle steps and protected in vivo in mouse challenge models, but single‑residue substitutions permitted escape, indicating the need for antigen designs that preserve key bridged epitopes or for antibody combinations.
Impact: Defines atomic‑level sites of vulnerability on EV‑D68 and demonstrates protective efficacy of VLP‑elicited antibodies, directly informing vaccine antigen selection and rationale for antibody cocktails to prevent escape and AFM risk.
Clinical Implications: Prioritize VLP platforms and epitope‑preserving antigens for EV‑D68 vaccine development; plan for multivalent or cocktail antibody strategies to mitigate single‑residue escape and protect against AFM‑associated strains.
Key Findings
- Five potently neutralizing mAbs from VLP‑immunized NHPs targeted overlapping epitopes near the VP1 fivefold axis.
- Cryo‑EM structures revealed epitopes bridging sialic‑acid and MFS6 receptor‑binding sites; antibodies disrupted multiple life‑cycle steps and protected in vivo, but single‑residue mutations enabled escape.
3. SIRT5-mediated FDX1 desuccinylation confers cuproptosis resistance in lung adenocarcinoma.
Preclinical mechanistic work identified SIRT5‑mediated desuccinylation of FDX1 (Lys84) as a mechanism that triggers TRIM8‑dependent ubiquitination and proteasomal degradation of FDX1, thereby conferring resistance to copper‑induced cuproptosis in lung adenocarcinoma. Pharmacologic SIRT5 inhibition (MC3482) combined with the cuproptosis inducer Elesclomol‑Cu produced synergistic tumor suppression in vivo, nominating a tractable combination strategy.
Impact: Reveals a novel, druggable resistance pathway to a cell‑death mechanism (cuproptosis) and provides in vivo evidence that targeting SIRT5 can sensitize tumors to copper‑based killing—opening a new therapeutic axis in lung adenocarcinoma.
Clinical Implications: Prompt early‑phase clinical evaluation of SIRT5 inhibitors combined with cuproptosis inducers in biomarker‑selected lung adenocarcinoma patients and assess FDX1 succinylation/abundance as predictive biomarkers of response.
Key Findings
- Copper stress upregulates SIRT5 and reduces global protein succinylation in lung adenocarcinoma cells.
- SIRT5 desuccinylates FDX1 at Lys84, inducing TRIM8‑mediated ubiquitination and proteasomal degradation, and SIRT5 inhibition plus Elesclomol‑Cu synergistically suppressed tumor growth in vivo.