Biology subjects

Torres, J. A.

Publications and source records attributed to Torres, J. A..

4 recordsLinked to original sources

bioRxiv2026

Co-optation of the regenerative role of type 2 alveolar cells in distal lung repair in mice by terminal airway epithelial cells in humans

The lung is endowed with extensive regenerative capacity. The principal cell of the lung is the type 1 alveolar epithelial (AT1) cell, which mediates gas exchange. Mouse models implicated surfactant-producing type 2 alveolar epithelial (AT2) cells as facultative stem cells that regenerate AT1 cells after injury through a transitional KRT8+ intermediate. Larger mammals, however, possess terminal and respiratory bronchioles that are lined by alveoli and by epithelial cells that are absent in mice. Here we show, using human pluripotent stem cell-derived lung organoids and comparative computational analysis, a prime role for terminal and respiratory bronchiole cells in AT1 regeneration without AT2 intermediate. Furthermore, cells similar to aberrant basaloid cells, profibrotic elements that accumulate in pulmonary fibrosis, are physiological intermediates in a more rapidly committing trajectory from terminal and respiratory bronchioles to AT1 cells marked by expression of KRT17, are regulated by Hippo and TGF{beta} signaling, and are transcriptionally distinct from mouse AT2-derived KRT8+ transitional cells. Our findings indicate that terminal and respiratory bronchioles in humans have to a large extent co-opted the regenerative and pathogenic functions of AT2 cells in mice. Efforts to enhance or correct human lung regeneration should therefore focus on facultative airway-derived alveolar progenitors using human models.

cell biology↗

bioRxiv2026

Playback calls help to increase the detectability of Coturnix coturnix (Common quail), a cryptic and widespread galliform

In cryptic or difficult-to-detect bird species, the monitoring schemes based on generalist detection methods may introduce bias into abundance estimates and population indices. This the case of the Coturnix coturnix (Common quail), a migratory Palearctic galliform, in which the use of passive detection methods within breeding birds monitoring schemes may not be efficient owing to its complex socio-sexual system and migratory behavior. For the first time, C.coturnix detectability was simultaneously compared using standard passive, generalist multispecies survey methods from the Pan-European Common Bird Monitoring Scheme (PECBMS) and a species-specific active survey employing female call playback. Surveys were conducted at 1,077 listening points within 107 transects over four breeding seasons (2022-2025) in open farmland landscapes dominated by cereal crops in Extremadura, south-western Spain. Detection counts differed substantially between methods: active surveys increased expected counts by 72% (95% CI: 59-85%) compared to passive surveys. The increase in C.coturnix detections elicited by playback showed a non-linear, density-dependent pattern, being highest at low passive abundances per listening point (maximum at 3-4 individuals) and stabilizing at intermediate abundances. This indicates that call playback is particularly effective at detecting individuals that would otherwise remain undetected. Our findings suggest that passive, multispecies surveys may underestimate C.coturnix abundance, especially in low-density populations. Integrating species-specific active methods into monitoring programs can improve detectability, generate more reliable population indices, and support evidence-based conservation and management strategies for this elusive species. LAY SUMMARYO_LIBird monitoring schemes guide conservation decisions across Europe, but generalist schemes based on passive methods may miss species that are hard to detect such as C.coturnix Common quail, a migratory farmland bird that hides in dense crops. In practice, only males spontaneously calling can be detected, hence passive methods could lead to underestimates of its abundance and even false absences in low-density areas. C_LIO_LIWe compared standard passive surveys with surveys that added a recorded female call (playback) to stimulate male responses. Across 1,077 listening points monitored over four breeding seasons in southwestern Spain, playback increased the number of birds detected by 72% compared with passive methods alone. C_LIO_LIThe improvement was strongest where C.coturnix numbers were low, showing that many individuals remain undetected without playback. Incorporating simple, species-specific methods into monitoring programs can produce more reliable population estimates and strengthen conservation and management decisions for this elusive species. C_LI

ecology↗

bioRxiv2025

Bacteria deliver a microtubule-binding protein into mammalian cells to promote colonization

Pathogenic Bordetella bacteria infect the ciliated respiratory epithelia of mammalian and avian hosts. Several bacterial proteins mediate host cell adhesion, but filamentous hemagglutinin (FhaB) is a principal adhesin because mutants lacking this protein exhibit profound colonization defects. Here, we show that FhaB carries a C-terminal microtubule-binding domain (FhaB-CT), which is translocated into the host-cell cytoplasm to promote bacterial colonization. Cryogenic electron microscopy of microtubule-bound FhaB-CT shows that the domain binds primarily to -tubulin through a network of polar interactions. Live-cell microscopy of infected tracheal explants reveals that FhaB-CT delivery is required for Bordetella to occupy a niche at the base of cilia on airway epithelia. Finally, we demonstrate that the microtubule-binding domain is required for long-term colonization of the mouse nasal cavity by B. pertussis. These observations suggest that the FhaB-CT domain is delivered into motile cilia, where it interacts with axonemal microtubules. We propose that Bordetella initially adhere to the tips of cilia, then deploy multiple FhaB adhesin molecules to migrate to the base of the cilial forest. This mechanism enables Bordetella to resist removal by the mucociliary escalator that clears the respiratory tract of microbes and debris.

microbiology↗

bioRxiv2023

Generation and expansion of transitional lung organoids from human pluripotent stem cells

Human lungs contain unique cell populations in distal respiratory airways (RAs). These populations accumulate in patients with lung injury, chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF). Their lineage potentials and roles are unknown, however. As they are absent in rodents, deeper understanding of these cells requires a human in vitro model. Here we report the generation from human pluripotent stem cells (hPSCs) of expandable spheres ( induced respiratory airway progenitors (iRAPs)) consisting of all RA-associated cell types. iRAPs could differentiate into type 1 (AT1) and type 2 alveolar (AT2) epithelial cells in defined conditions, showing that alveolar cells can be derived from RAs. iRAPs with deletion of HPS1, which causes pulmonary fibrosis in humans, display defects that are hallmarks of IPF, indicating involvement of intrinsic dysfunction of RA-associated cells in IPF. iRAPs thus provide a model to gain insight into human lung regeneration and into pathogenesis of IPF.

cell biology↗