Marques M, Wong YX, Sun Z
… +5 more, Yasmin A, Taylor JP, Ruggieri A, Tuthill TJ, Locker N
PLoS Pathog
· 2026 Jun · PMID 42275447
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Foot-and-mouth disease virus (FMDV) is highly contagious among cloven-hoofed animals and poses a major threat to the livestock industry worldwide. A fundamental gap in knowledge for high consequence viruses such as FMDV...Foot-and-mouth disease virus (FMDV) is highly contagious among cloven-hoofed animals and poses a major threat to the livestock industry worldwide. A fundamental gap in knowledge for high consequence viruses such as FMDV is understanding how the virus evolved to evade cellular antiviral responses. FMDV belongs to the Picornaviridae, a family of positive-sense single-stranded RNA viruses. The detection of viral double-stranded viral RNA intermediates during infection can trigger both the assembly of cytoplasmic stress granules (SGs) and the activation of the RIG-I-like receptors (RLR)-mediated innate immune response (IIR). FMDV has been proposed to antagonize these mechanisms, suggesting that both can limit viral replication. In this study, we investigate the dynamic and importance of SG assembly for IIR activation upon dsRNA stimulation or FMDV replication in porcine epithelial kidney cells. First, we show that the formation of SG following a challenge with poly(I:C), a viral dsRNA mimic, does not modulate the activation of IIR. Our data further reveal transient assembly of SG during FMDV infection followed by virus-induced cleavage of G3BP1, a core SG protein. While SG assembly does not impact viral replication or antiviral response activation, we demonstrate that preventing their disassembly negatively impacts FMDV replication. Overall, we show that SGs assembly during infection does not modulate viral replication and is uncoupled from IIR activation, while FMDV actively cleaves G3BP1 by a 3Cpro-mediated mechanism to promote their disassembly, suggesting a potential antiviral role for persistent SGs.
PLoS Pathog
· 2026 Jun · PMID 42275403
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The Hippo signalling pathway has emerged as an important regulator of host-virus interactions, linking antiviral immunity, viral replication, inflammation, and tissue remodelling. Recent studies show that upstream Hippo...The Hippo signalling pathway has emerged as an important regulator of host-virus interactions, linking antiviral immunity, viral replication, inflammation, and tissue remodelling. Recent studies show that upstream Hippo kinases such as MST1/2 and LATS1/2 often support antiviral responses, whereas YAP and TAZ can suppress innate immune signalling and may be exploited by viruses to promote infection. However, these effects are highly context dependent, varying according to viral species, cell type, infection stage, interferon signalling, inflammatory cues, and tissue damage. This short review summarises current evidence for Hippo-virus crosstalk and highlights how this pathway may shape both acute antiviral defence and longer-term pathological remodelling. We also discuss therapeutic opportunities and challenges, emphasising that targeting Hippo signalling requires caution because of its dual roles in antiviral immunity and tissue repair.
Zhu C, Yao C, Liu R
… +6 more, Sun T, Zou C, Liu Q, Rasmann S, Turlings TCJ, Li Y
PLoS Pathog
· 2026 Jun · PMID 42275396
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Herbivore-induced plant volatiles (HIPVs) are known to prime neighboring plants for enhanced defense, but the molecular basis for this phenomenon remains poorly understood, particularly in cotton. Here, we demonstrate fo...Herbivore-induced plant volatiles (HIPVs) are known to prime neighboring plants for enhanced defense, but the molecular basis for this phenomenon remains poorly understood, particularly in cotton. Here, we demonstrate for cotton plants that exposure to volatiles induced by the cotton bollworm (Helicoverpa armigera Hübner; CBW), enhances resistance against subsequent CBW attack, as evidenced in both laboratory and semi-field trials. While HIPV exposure alone did not elicit direct defense activation, it primed the jasmonic acid (JA) signaling pathway, leading to accelerated induction of JA biosynthesis genes and elevated JA accumulation upon herbivory. That this primed resistance is JA-dependent, was confirmed by treating HIPV-exposed plants with JA biosynthesis inhibitors, which completely abolished the priming effects. We further found that HIPV-primed plants exhibited significantly higher accumulation of the key defensive metabolite gossypol following larval feeding. The role of gossypol-reliant defenses was confirmed by using a glandless cotton mutant (gl2gl2gl3gl3) deficient in gossypol and related terpenoid aldehydes. The combined results reveal that CBW-induced volatiles prime anti-herbivore resistance in cotton by potentiating the JA signaling pathway, which in turn enhances gossypol biosynthesis upon actual herbivore attack. This new insight into the physio-ecological mechanisms underlying airborne defense priming in cotton also highlights its potential application in sustainable pest management.
PLoS Pathog
· 2026 Jun · PMID 42275395
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Many DNA viruses including polyomaviruses (PyVs) enter the host nucleus to cause infection, although how this is accomplished is unclear. To infect cells, the prototype PyV SV40 targets to the Nesprin-2 outer nuclear mem...Many DNA viruses including polyomaviruses (PyVs) enter the host nucleus to cause infection, although how this is accomplished is unclear. To infect cells, the prototype PyV SV40 targets to the Nesprin-2 outer nuclear membrane protein and enters the nucleus via the nuclear pore complex (NPC). Host factors that function with Nesprin-2 to target SV40 to the nuclear membrane and drive NPC-dependent nuclear entry are unknown. Here we demonstrate that the SUN1 inner nuclear membrane protein acts coordinately with its binding-partner Nesprin-2 to target cytosol-localized SV40 to the nuclear membrane. Strikingly, despite localizing to the perinuclear space, the SUN domain of SUN1 plays a crucial role in Nesprin-2-dependent recruitment of cytosolic SV40. After targeting, SV40 binds to the NPC-associated importin receptor KPNA4, which translocates the virus into the nucleus. Our results reveal how a DNA virus exploits the Nesprin-2-SUN1-KPNA4 axis for stepwise targeting and entry into the nucleus to cause infection.
Palmieri E, Belciug GF, Nonne F
… +9 more, Massai L, Valensin S, De Rosa A, Berlanda Scorza F, Rondini S, Carducci M, Rossi O, Micoli F, Giannelli C
PLoS Pathog
· 2026 Jun · PMID 42268929
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MAPS technology represents an innovative approach for the development of polysaccharide-based vaccines, relying on the affinity interaction between biotin and rhizavidin (rhavi), with potential for enhanced coverage thro...MAPS technology represents an innovative approach for the development of polysaccharide-based vaccines, relying on the affinity interaction between biotin and rhizavidin (rhavi), with potential for enhanced coverage through the incorporation of pathogen-specific proteins. Due to its flexibility, this platform is particularly attractive for the development of multivalent vaccines, as it is required for Klebsiella pneumoniae, a multidrug-resistant bacterium highlighted as prevalent cause of neonatal sepsis in low- and middle-income countries, against which no vaccines are currently available. In this work MrkA, a potential protective pathogen-specific protein antigen, was combined in a MAPS complex with K2 as model for Klebsiella K-antigen. The impact of sugar chain length, protein to polysaccharide ratio, and MAPS complex size on the immune response elicited in animal models was evaluated. Results showed that longer polysaccharides and higher protein/K-antigen ratios enhanced the immunogenicity in rabbits. Different proteins, i.e., rhavi alone and CP1-rhavi from Streptococcus pneumoniae, were also evaluated as carrier, showing that the protein antigen fused to rhavi can play a significant role on the resulting MAPS polysaccharide specific immunogenicity. Passive transfer of rabbit polyclonal sera from the most immunogenic MAPS complex was able to protect mice from challenge with a K2 clinical isolate. This work supports the rational design of a K-antigen MAPS-based vaccine against Klebsiella pneumoniae.
Jin L, Chen X, Pang C
… +6 more, Huang Y, Ji C, Zhang Y, Liu X, Sun Y, Chen Y
PLoS Pathog
· 2026 Jun · PMID 42268909
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Bacterial diseases pose a major threat to global agriculture and food security. Bactericides are highly effective in disease control due to their direct antibacterial effect. However, it causes "life or death" selection...Bacterial diseases pose a major threat to global agriculture and food security. Bactericides are highly effective in disease control due to their direct antibacterial effect. However, it causes "life or death" selection pressure on the target bacteria and can lead to bactericide resistance. Quorum sensing inhibitors exert indirect antibacterial effect that weakens their virulence and combined use of bactericides and quorum sensing inhibitors demonstrated more significant disease control than a single agent. In this study, dioctyldiethylenetriamine, a bactericide that has previously been proven to have a direct antibacterial effect, exhibited an indirect antibacterial effect that weakened bacterial virulence. Using transposon sequencing, we found that the quorum sensing system, which is closely related to virulence in Xanthomonas oryzae pv. oryzae (Xoo, PXO99A), was significantly affected by dioctyldiethylenetriamine. It was further found that RpfG, which is responsible for transduction of the quorum sensing signal molecules in PXO99A, was significantly inhibited at both transcriptional and translational levels after dioctyldiethylenetriamine treatment, resulting in impaired phosphodiesterase activity, which in turn caused bacterial quorum quenching (QQ). QQ not only weakened the virulence of the bacteria, but also reduced their motility, which could effectively prevent the bacteria from escaping the direct antibacterial effect of dioctyldiethylenetriamine, thus providing a more effective control effect. Finally, we found that the QQ induced by dioctyldiethylenetriamine appeared to be specific, occurring in a subset of bacteria containing RpfG. The interspecific competitiveness within the same ecological niche also appeared to be weakened, which was accompanied with QQ. These findings have enriched our understanding of the antibacterial mechanism of bactericides and provided a theoretical basis for the scientific and rational use of bactericides as well as the development of "RpfG-based" indirect antibacterial agents with both efficient antibacterial activity and ecological safety.
Zhang Y, Shi Y, Zou Y
… +6 more, Li L, Dian Z, Chen Y, Zhao H, Wang J, Sun Y
PLoS Pathog
· 2026 Jun · PMID 42263107
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Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor strongly associated with Epstein-Barr virus (EBV) infection. EBV-mediated dysregulation of host microRNAs (miRNAs) contributes to NPC pathogenesis, but the f...Nasopharyngeal carcinoma (NPC) is a malignant epithelial tumor strongly associated with Epstein-Barr virus (EBV) infection. EBV-mediated dysregulation of host microRNAs (miRNAs) contributes to NPC pathogenesis, but the functions of many EBV-regulated host miRNAs remain incompletely defined. miR-10b-3p is markedly downregulated in EBV-positive NPC, yet its biological significance and downstream mechanism remain unclear. Here, we found that miR-10b-3p was reduced in EBV-positive NPC tissues and was further suppressed following EBV infection of non-malignant nasopharyngeal epithelial cells and EBV-negative NPC cell lines. Restoration of miR-10b-3p expression markedly inhibited cell proliferation, colony formation, migration, invasion, and epithelial-mesenchymal transition (EMT) in EBV-positive NPC cells, whereas inhibition of miR-10b-3p in EBV-negative NPC cells produced the opposite effects. In nude mouse xenograft and lung metastasis models, overexpression of miR-10b-3p significantly reduced tumor growth and pulmonary metastasis. Mechanistically, miR-10b-3p directly targeted the 3'-UTR of integrin subunit alpha V (ITGAV), leading to decreased ITGAV expression and subsequent attenuation of STAT5 and ERK1/2 signaling. Forced ITGAV expression partially reversed the suppressive effects of miR-10b-3p on tumor cell proliferation, migration, invasion, and EMT. Moreover, miR-10b-3p levels were inversely correlated with ITGAV expression in NPC tissues. Collectively, these findings identify an EBV-regulated miR-10b-3p/ITGAV/STAT5-ERK1/2 axis in NPC and show that loss of miR-10b-3p promotes tumor growth and metastasis by relieving ITGAV repression, suggesting potential therapeutic targets for EBV-associated NPC.
Beckman I V RL, Victoria B, Santiago FZ
… +10 more, Echeverria GN, Pinheiro BV, D T Torres M, Suits L, Garcia S, Wantuch PL, de la Fuente-Nunez C, Eswara P, Rosen DA, Fleeman RM
PLoS Pathog
· 2026 Jun · PMID 42263057
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[This corrects the article DOI: 10.1371/journal.ppat.1013437.].[This corrects the article DOI: 10.1371/journal.ppat.1013437.].
Jaki L, Full F, Gieraths U
… +5 more, Falcone V, Ruzsics Z, Hengel H, Panning M, Fuchs J
PLoS Pathog
· 2026 Jun · PMID 42258558
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Severe HSV-1 disease is treated with potent antiviral drugs, in particular aciclovir (ACV) and its derivatives. However, long-term drug exposure in immunocompromised patients can lead to the emergence of ACV-resistant HS...Severe HSV-1 disease is treated with potent antiviral drugs, in particular aciclovir (ACV) and its derivatives. However, long-term drug exposure in immunocompromised patients can lead to the emergence of ACV-resistant HSV-1 strains and clinical treatment failure. To understand how phenotypic resistances develop on a genomic level, we analyzed the influence of ACV selection pressure on the viral genome of different HSV-1 virus strains in vitro. Growth kinetics and IC50 determination showed ACV resistance development within a single passage. Next, we performed ultra-deep, non-targeted full-genome Illumina sequencing of the parental and ACV-adapted HSV-1 strains. Interestingly, resistance-conferring mutations rapidly arose in the viral genes UL23 and UL30 and were already present in the parental ACV-naïve strains at extremely low variant frequencies. Based on these findings, we hypothesized that low- frequency mutations develop during continued viral replication. To test this hypothesis, a primary rescued recombinant K17 + strain was repeatedly passaged. Continued passaging indeed increased the proportion of a subset of minor variants and allowed resistance development after, but not before, 10 consecutive passages. In summary, we show that minor variants can facilitate adaptation of HSV-1 populations to selective pressures such as pharmacological inhibition of replication. These findings highlight that deep sequencing might allow early detection of resistance mutations potentially supporting antiviral drug stewardship.
Rehm TM, Straub E, Doorbar J
… +5 more, Grundhoff A, Günther T, Blümke P, Iftner T, Stubenrauch F
PLoS Pathog
· 2026 Jun · PMID 42258548
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Persistent infections with high-risk human papillomaviruses (HPV) can result in different malignancies. Productive replication of HPV is normally restricted to suprabasal keratinocytes that have entered terminal differen...Persistent infections with high-risk human papillomaviruses (HPV) can result in different malignancies. Productive replication of HPV is normally restricted to suprabasal keratinocytes that have entered terminal differentiation and is characterized by vegetative genome amplification, activation of the late promoter, and expression of the viral late E4 protein. Cells undergoing productive replication remain in a prolonged G2 phase and exit the cell cycle without division. The viral E8^E2 protein binds to NCoR/SMRT co-repressor complexes to repress viral transcription and replication in undifferentiated keratinocytes, but the biological rationale for this repression has remained unclear. Recent studies have revealed that Mus musculus PV1 E8^E2 prevents late viral E4 expression in undifferentiated cells to enable tumor formation in vivo. Here, we demonstrate that loss of E8^E2 function in high-risk HPV31 leads to inappropriate activation of genome amplification in undifferentiated keratinocytes, resulting in expression of E4 protein and cell cycle perturbation which explains why HPV31 E8^E2 mutant genomes fail to be maintained as episomes and instead are always found integrated in surviving cell lines. Interestingly, this is independent from E4 expression suggesting that vegetative genome amplification is sufficient to prevent cell division. Remarkably, depletion of NCoR/SMRT complexes in cell lines maintaining HPV31 episomes phenocopies E8^E2 inactivation and induces genome amplification and E4 expression. Notably, most E4-positive cells generated by E8^E2 inactivation or NCoR/SMRT depletion retain basal-like characteristics, indicating that genome amplification and E4 expression can be uncoupled from differentiation when E8^E2 repression is relieved. Interestingly, differentiation diminishes the effects of NCoR/SMRT depletion, suggesting that E8^E2 activity is likely inactivated during differentiation to permit productive replication. Collectively, these findings identify E8^E2 as a critical gatekeeper preventing premature genome amplification and E4 expression in basal keratinocytes and suggest that targeting the E8^E2-NCoR/SMRT interaction may represent a novel antiviral strategy.
Circu M, Castore R, Latimer B
… +4 more, Shames S, Roy CR, Dragoi AM, Ivanov SS
PLoS Pathog
· 2026 Jun · PMID 42258528
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Legionella pneumophila is an environmental Gram-negative bacterium that parasitizes unicellular protozoa and can cause severe pulmonary infections when aerosolized bacteria are inhaled by humans. One critical aspect of L...Legionella pneumophila is an environmental Gram-negative bacterium that parasitizes unicellular protozoa and can cause severe pulmonary infections when aerosolized bacteria are inhaled by humans. One critical aspect of Legionella pathogenesis is the establishment in the cytosol of infected macrophages of a unique ER-derived vacuole, that requires a sustained supply of host lipids during expansion. Subversion of pro-lipogenic pathways downstream of the metabolic checkpoint kinase mTOR (Mechanistic Target of Rapamycin) are critical for niche expansion. In eukaryotic cells, amino acids sufficiency and growth factor sensory signals converge on mTOR to ensure metabolic processes are coupled to nutrients/energy availability. Legionella can trigger mTOR signaling in infected cells by increasing the intracellular abundance of amino acids through inhibition of host translation. Here, we describe a novel mechanism by which Legionella sensitizes mTOR in infected macrophages. A forward genetic screen identified Lpg0393 protein as a putative bacterial mTOR regulator that contains a VPS9-domain typically found in eukaryotic GEFs (Guanine nucleotide exchange factors) for Rab5 GTPase family members (Rab5/Rab21/Rab22). We uncovered that Lpg0393 lowers the activation threshold for mTOR signaling upon stimulation with arginine or leucine by promoting anterograde trafficking of amino acid permeases through subversion of the small GTPases Rab21 and Rab22. Data from cells expressing either a bacterial or a eukaryotic mTOR sensitizing factor uncovered two distinct non-cytosolic Arg/Leu pools that fuel mTOR activation in parallel - one regulated by Rab21/22 and the other by Rab5. Consistent with the role of mTOR in expansion of the Legionella-occupied organelle, deletion of Lpg0393 also resulted in premature vacuolar rupture in a mTOR-dependent manner. All together, we have identified a novel bacterial mTOR regulator and consistent with its reported functions we propose Lpg0393 is named as BinA (Bacterial initiator of TORC1 signaling and an activator of Rab5 family GTPases).
PLoS Pathog
· 2026 Jun · PMID 42247472
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Benzimidazoles, a widely used class of anthelmintic drugs, target beta-tubulin, disrupt microtubule formation, and delay nematode development. In parasitic nematodes, mutations in beta-tubulin genes are predicted to inhi...Benzimidazoles, a widely used class of anthelmintic drugs, target beta-tubulin, disrupt microtubule formation, and delay nematode development. In parasitic nematodes, mutations in beta-tubulin genes are predicted to inhibit benzimidazole binding and are associated with resistance. In the free-living nematode Caenorhabditis elegans, loss-of-function mutations in the beta-tubulin gene ben-1 cause benzimidazole resistance. Although several beta-tubulin mutations serve as established markers of resistance, the prediction of the effects of novel variants in different nematode species remains challenging. Here, we identified novel beta-tubulin variants predicted to confer benzimidazole resistance across wild strains in three Caenorhabditis species: C. elegans, Caenorhabditis briggsae, and Caenorhabditis tropicalis. The three Caenorhabditis species are experimentally tractable, have characterized beta-tubulin gene complements, and defined natural niches, which allowed us to identify variants in beta-tubulin genes and test which variants are associated with resistance. We hypothesized that, if these species experienced similar selective pressures, they would evolve resistance to benzimidazoles by mutations in a beta-tubulin gene (tbb-1, tbb-2, mec-7, tbb-4, and ben-1). In the three Caenorhabditis species, we tested all strains harboring variants in the five conserved beta-tubulin genes for benzimidazole resistance. In C. elegans, we found that a heterogeneous set of variants in ben-1 were associated with resistance. By contrast, only two variants in C. briggsae ben-1 (W21stop and Q134H) were associated with resistance, suggesting selection acts differently in C. briggsae than in C. elegans despite overlapping geographic ranges between the two species. C. tropicalis was distinct from the other two species, where no strains with variants in any beta-tubulin gene were resistant. We generated deletions of ben-1 in C. briggsae and C. tropicalis and confirmed that loss of ben-1 confers resistance in both species. Our findings reveal species-specific patterns of beta-tubulin-mediated benzimidazole resistance and emphasize that prediction of variants in beta-tubulin genes alone is not sufficient to predict resistance, especially across diverse Caenorhabditis species.
Myers A, Chandravanshi M, Whitmore LS
… +18 more, Kohrn BF, Negash A, Nguyen DN, Ralli-Jain P, Cruickshank K, Upadhyay AA, Charles T, Edwards CT, Hunter E, Amara RR, Korzeniowski MK, Niu L, Pozharski E, Tolbert WD, Bosinger SE, Kennedy SR, Pazgier M, Derdeyn CA
PLoS Pathog
· 2026 Jun · PMID 42247468
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High serum neutralization following BG505 SOSIP.664 envelope trimer immunization was associated with protection against BG505.SHIV challenge in rhesus macaques in a previous study. In an animal that developed high titer,...High serum neutralization following BG505 SOSIP.664 envelope trimer immunization was associated with protection against BG505.SHIV challenge in rhesus macaques in a previous study. In an animal that developed high titer, durable neutralization against a glycan hole on envelope gp120, high throughput, longitudinal, antigen-specific B cell receptor sequencing was conducted. This analysis of more than 4,700 antigen-specific B cells revealed marked intra-clonal expansion and divergence from germline, including three abundant clonotypes that produced autologous neutralizing monoclonal antibodies. Monoclonal antibodies from the neutralizing clonotypes and two other expanded non-neutralizing clonotypes targeted epitopes in the same glycan hole, with neutralizers also demonstrating different capacities to obstruct CD4 binding. Cryo-electron microscopy structures of four neutralizing monoclonal antibodies revealed that they bound to glycan hole epitopes using distinct binding modes. One neutralizing antibody displaced a glycan in the loop V5 upon binding and its footprint includes the CD4 binding loop. The findings provide insight into how antibody recognition of a prominent glycan hole could facilitate different mechanisms of neutralization while underscoring how intra-clonal expansion and maturation with repeated BG505 SOSIP.664 immunization drove high serum neutralization.
Liu PP, Zhang M, Wei Z
… +4 more, Wang WG, Wang JX, Li Y, Wang XW
PLoS Pathog
· 2026 Jun · PMID 42241470
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A balanced immune response is required to limit the microbes without causing damage to the host. The forkhead box O (FoxO)-mediated immunity plays a pivotal role in maintaining microbiota homeostasis by regulating the ex...A balanced immune response is required to limit the microbes without causing damage to the host. The forkhead box O (FoxO)-mediated immunity plays a pivotal role in maintaining microbiota homeostasis by regulating the expression of antimicrobial effectors in non-infected arthropods. However, the mechanism by which FoxO activity is appropriately coordinated remains unclear. In this study, we elucidated a feedback loop that coordinates FoxO-mediated antibacterial response using shrimp as a model. In this feedback loop, the commensal hemolymph microbiota maintains basal activation of FoxO, which determines the expression of antimicrobial effectors, platelet-derived growth factor/vascular endothelial growth factor (PDGF/VEGF)-related factor 1 (Pvf1) and PDGF/VEGF-related receptor 4 (Pvr4). This ligand-receptor system enhances phosphatidylinositol 3-kinase (PI3K)-protein kinase B (PKB/Akt) activity, limiting the excessive activation of FoxO and expression of antimicrobial effectors. This feedback loop is essential for maintaining the equilibrium of the microbiota, and its strength increases following a pathogenic infection, reducing the incidence of infection-induced mortality and tissue damage. This study revealed a microbiota-initiated feedback loop that balances FoxO-mediated antibacterial immunity for the establishment of microbiota homeostasis, and provides new insights into the functional diversification of PDGF/VEGF signaling.
DeFranco JP, Atkinson ZN, Crowell J
… +5 more, Shi X, Kim S, Sun JL, Kane SJ, Telling GC
PLoS Pathog
· 2026 Jun · PMID 42241459
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Prions are unique infectious agents because different conformational properties of their constituent proteins are responsible for the manifestation of distinct strains. While prion replication in humans with sporadic Cre...Prions are unique infectious agents because different conformational properties of their constituent proteins are responsible for the manifestation of distinct strains. While prion replication in humans with sporadic Creutzfeldt-Jakob disease and cattle with bovine spongiform encephalopathy is primarily limited to the central nervous system (CNS), a seminal feature of chronic wasting disease (CWD) in cervids is high infectious titers in peripheral tissues, including skeletal muscles and the lymphoreticular system. Although extensive studies have assessed prion properties in the CNS, our understanding of prions in peripheral tissues remains limited. Here, we compared the strain properties of CWD prions in peripheral and CNS tissues of gene-targeted (Gt) mice. Our studies reveal differences in the biochemical and conformational properties of CWD prions, as well as the prion levels, between peripheral and CNS tissues. While this finding suggested that these tissues harbored distinct CWD prions, transmissions of muscle, spleen, and brain homogenates to Gt mice by the intraperitoneal route produced convergent strain properties. Importantly, transmission of these tissues by the intracerebral route resulted in different disease phenotypes than intraperitoneal inoculations. Additionally, while prion infection of CWD-susceptible cells revealed different titers in muscle, spleen, and brain tissues, the conformational properties of the resulting de novo prions were indistinguishable. While our findings support a role for tissue-specific cofactors that affect the biochemical and conformational properties of prions, they also show that these parameters do not solely dictate disease outcomes and that additional factors, particularly the route of inoculation, exert a more pronounced influence on strain outcomes.
Schweizer PE, Elmagzoub WA, Idris SM
… +18 more, Eltom KH, Okuni JB, Ojok L, Eltayeb E, Amanzada A, Quaas M, Aust G, Harzer M, Vahlenkamp TW, Jehmlich N, Schneider MR, Grassl GA, Puschhof J, Krohn K, Goethe R, Truyen U, Galle J, Abd El Wahed A
PLoS Pathog
· 2026 Jun · PMID 42241455
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Intestinal organoids are powerful tools for modeling host-pathogen interactions, yet culture-induced artifacts remain poorly defined. Here, we performed time-course transcriptomic profiling of patient-derived ileal organ...Intestinal organoids are powerful tools for modeling host-pathogen interactions, yet culture-induced artifacts remain poorly defined. Here, we performed time-course transcriptomic profiling of patient-derived ileal organoids microinjected with Mycobacterium avium subsp. paratuberculosis (MAP) or treated with the swelling agent forskolin (FSK) and compared expression changes to untreated controls. Our analysis revealed that culture-associated transcriptional drift was the primary driver of gene expression changes over the 48-hour time course, likely obscuring pathogen-specific responses. This drift involved progressive downregulation of metabolic genes accompanied by the upregulation of genes with high GC content. Although FSK treatment improved. microinjection efficiency, it also introduced additional confounding effects, including transient activation of apoptotic pathways and upregulation of inflammatory genes that resolved within two days. While MAP infection did not produce significant single-gene responses, gene set analysis revealed significant infection-associated effects. Spatial transcriptomics further demonstrated that multiple enterocyte gene sets became downregulated during culture, independent of their normal crypt-villus expression pattern. Gene sets typically expressed at the crypt-villus junction showed the greatest downregulation. Notably, MAP infection selectively counteracted these culture-induced changes, preserving gene expression patterns characteristic of the upper villus epithelium. These findings indicate that both metabolic stress and pharmacological interventions can substantially confound organoid-based infection models. More broadly, they underscore the importance of spatially resolved transcriptomics and appropriate temporal controls to distinguish genuine pathogen responses from culture-related artifacts. To our knowledge, no previous studies have used human intestinal organoids to model MAP infection or characterized the epithelial transcriptomic response. This work establishes critical frameworks for investigating MAP's role in Crohn's disease pathogenesis.
Jain M, Cannac F, Agrawal S
… +7 more, Lee WH, Loeffler JR, Fernández-Quintero ML, González-Páez GE, Moskovitz R, Ward AB, Wilson IA
PLoS Pathog
· 2026 Jun · PMID 42234703
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Monoclonal antibodies (mAbs) targeting the Plasmodium falciparum circumsporozoite protein (PfCSP) have demonstrated substantial promise in preventing malaria infection and disease. PfCSP is characterized by a central reg...Monoclonal antibodies (mAbs) targeting the Plasmodium falciparum circumsporozoite protein (PfCSP) have demonstrated substantial promise in preventing malaria infection and disease. PfCSP is characterized by a central region composed of repetitive NANP motifs, which serve as major targets for protective antibodies. Several potent mAbs targeting this region exhibit homotypic Fab-Fab interactions, which enhance antigen binding and contribute to their neutralization potency. Among these, mAb 399, encoded by the IGHV3-49/IGKV2D-29 (VH3-49/VK2D-29) germline lineages, forms head-to-head inter-Fab contacts mediated primarily by germline-encoded residues. Here, we determined X-ray and cryo-EM structures of two additional Fabs, derived from the same germline lineages, 7160 and 7118, in their unliganded forms and with PfCSP-derived peptides or recombinant shortened CSP. Both Fabs bound NANP6 repeats with high affinity (KD 6-10 nM). Fab 7160 formed germline-encoded inter-Fab homotypic interactions resembling Fab 399, indicating a conserved and preconfigured mode of antigen recognition. In contrast, Fab 7118 does not form homotypic contacts and adopts a distinct binding mode, which precludes inter-Fab interactions. These findings highlight the structural versatility of VH3-49/VK2D-29-derived antibodies and demonstrate that their CDR loop variations can modulate antibody conformation, homotypic Fab-Fab interactions, and epitope engagement. Our study further defines this class of germline-encoded anti-CSP antibodies and provides mechanistic insights into how they achieve high-avidity binding and protective immunity either through or independent of pre-configured Fab-Fab interactions with important implications for germline-targeting malaria vaccine design.
Okoye IC, Lamb IM, Cheung YW
… +10 more, Morrisey JM, Sharma M, Kumar R, Dass S, Shukla A, Rell RS, Mather MW, Llinás M, Chang YW, Vaidya AB
PLoS Pathog
· 2026 Jun · PMID 42234699
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Malaria remains an urgent threat to global health as the mortality and infection rates keep rising annually and our frontline antimalarials are becoming less effective due to the emergence and spread of resistance-confer...Malaria remains an urgent threat to global health as the mortality and infection rates keep rising annually and our frontline antimalarials are becoming less effective due to the emergence and spread of resistance-conferring mutations. Although the mitochondrion of P. falciparum parasites is a validated drug target, there remain many uncharacterized mitochondrial proteins. The goal of this study was to investigate the essentiality and functions of a recently identified mitochondrial protein - PF3D7_0707400. Our results show that PF3D7_0707400 is an ATAD3A homolog that is essential to parasite survival and is present in a megadalton complex that is critical for multiple mitochondrial processes such as mitochondrial RNA stability, membrane potential, ultrastructure, and protein import. ATAD3A has been previously studied in multicellular eukaryotes and has been implicated in several childhood mitochondrial diseases, with suggested functions in mitochondrial nucleoid stabilization, mitochondrial RNA translation, and mitochondrial inner membrane integrity. This study is the first characterization, to our knowledge, of ATAD3A in unicellular organisms. Our findings here expand our knowledge on apicomplexan mitochondrial biology and our arsenal of potential antimalarial drug targets.