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2.
Viruses ; 16(6)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38932155

RESUMEN

COVID-19 is a spectrum of clinical symptoms in humans caused by infection with SARS-CoV-2. The coalescence of SARS-CoV-2 with seasonal respiratory viruses, particularly influenza viruses, is a global health concern. To understand this, transgenic mice expressing the human ACE2 receptor (K18-hACE2) were infected with influenza A virus (IAV) followed by SARS-CoV-2 and the host response and effect on virus biology was compared to K18-hACE2 mice infected with IAV or SARS-CoV-2 alone. The sequentially infected mice showed reduced SARS-CoV-2 RNA synthesis, yet exhibited more rapid weight loss, more severe lung damage and a prolongation of the innate response compared to the singly infected or control mice. Sequential infection also exacerbated the extrapulmonary encephalitic manifestations associated with SARS-CoV-2 infection. Conversely, prior infection with a commercially available, multivalent live-attenuated influenza vaccine (Fluenz Tetra) elicited the same reduction in SARS-CoV-2 RNA synthesis, albeit without the associated increase in disease severity. This suggests that the innate immune response stimulated by IAV inhibits SARS-CoV-2. Interestingly, infection with an attenuated, apathogenic influenza vaccine does not result in an aberrant immune response and enhanced disease severity. Taken together, the data suggest coinfection ('twinfection') is deleterious and mitigation steps should be instituted as part of the comprehensive public health and management strategy of COVID-19.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Modelos Animales de Enfermedad , Virus de la Influenza A , Ratones Transgénicos , Infecciones por Orthomyxoviridae , SARS-CoV-2 , Animales , COVID-19/inmunología , COVID-19/virología , Ratones , SARS-CoV-2/inmunología , Infecciones por Orthomyxoviridae/virología , Infecciones por Orthomyxoviridae/inmunología , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Humanos , Coinfección/virología , Pulmón/virología , Pulmón/patología , Encefalitis Viral/virología , Encefalitis Viral/inmunología , Vacunas contra la Influenza/inmunología , Femenino , Inmunidad Innata
3.
Curr Pharm Teach Learn ; 16(9): 102121, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38865874

RESUMEN

BACKGROUND AND PURPOSE: Near-peer teaching is an innovative approach to teaching the skills of supervising and precepting while benefiting students with different levels of experience and academic training. This study describes near-peer activities in skills-based laboratory courses that provided opportunities for one-on-one teaching to benefit learners in the introductory lab courses while simultaneously training more advanced students for future supervisory and precepting roles. EDUCATIONAL ACTIVITY & SETTING: Three community pharmacy near-peer teaching simulations were designed and implemented: 1) Patient Counseling and Medication Adherence, 2) Dispensing and Patient Counseling, and 3) Drug Utilization Review and Prescriber Calls. These activities took place over two semesters of a pharmacy skills lab with all first- and third-year Doctor of Pharmacy students. FINDINGS: In Autumn 2019, 80% (111/139) of P1s and 67% (80/119) of P3s responded to the course evaluation survey. In Spring 2020, 73% (100/137) of P1s and 68% (80/118) of P3s responded to the course evaluation survey. The P3s reported increased confidence in their ability to provide meaningful feedback, while P1s reported increased confidence in communicating with patients and healthcare providers. Performance data revealed that most P1s and P3s completed dispensing and communication activities accurately using a near-peer approach. Overall, the P1s and P3s felt the activities were valuable learning experiences. SUMMARY: The near-peer activities described in this study fill a gap in the training of pharmacy graduates for future precepting and supervisory roles. Evaluation of these near-peer activities suggest that both junior and senior learners benefit from simulated preceptor-intern interactions, supporting this innovative approach to address supervisory and precepting responsibilities.


Asunto(s)
Grupo Paritario , Humanos , Educación en Farmacia/métodos , Educación en Farmacia/normas , Educación en Farmacia/estadística & datos numéricos , Preceptoría/métodos , Preceptoría/normas , Preceptoría/estadística & datos numéricos , Encuestas y Cuestionarios , Estudiantes de Farmacia/estadística & datos numéricos , Estudiantes de Farmacia/psicología , Entrenamiento Simulado/métodos , Entrenamiento Simulado/normas , Entrenamiento Simulado/estadística & datos numéricos , Competencia Clínica/normas , Competencia Clínica/estadística & datos numéricos
4.
PLoS One ; 19(5): e0298864, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38753630

RESUMEN

Fibrotic remodeling is the primary driver of functional loss in chronic kidney disease, with no specific anti-fibrotic agent available for clinical use. Transglutaminase 2 (TG2), a wound response enzyme that irreversibly crosslinks extracellular matrix proteins causing dysregulation of extracellular matrix turnover, is a well-characterized anti-fibrotic target in the kidney. We describe the humanization and characterization of two anti-TG2 monoclonal antibodies (zampilimab [hDC1/UCB7858] and BB7) that inhibit crosslinking by TG2 in human in vitro and rabbit/cynomolgus monkey in vivo models of chronic kidney disease. Determination of zampilimab half-maximal inhibitory concentration (IC50) against recombinant human TG2 was undertaken using the KxD assay and determination of dissociation constant (Kd) by surface plasmon resonance. Efficacy in vitro was established using a primary human renal epithelial cell model of tubulointerstitial fibrosis, to assess mature deposited extracellular matrix proteins. Proof of concept in vivo used a cynomolgus monkey unilateral ureteral obstruction model of chronic kidney disease. Zampilimab inhibited TG2 crosslinking transamidation activity with an IC50 of 0.25 nM and Kd of <50 pM. In cell culture, zampilimab inhibited extracellular TG2 activity (IC50 119 nM) and dramatically reduced transforming growth factor-ß1-driven accumulation of multiple extracellular matrix proteins including collagens I, III, IV, V, and fibronectin. Intravenous administration of BB7 in rabbits resulted in a 68% reduction in fibrotic index at Day 25 post-unilateral ureteral obstruction. Weekly intravenous administration of zampilimab in cynomolgus monkeys with unilateral ureteral obstruction reduced fibrosis at 4 weeks by >50%, with no safety signals. Our data support the clinical investigation of zampilimab for the treatment of kidney fibrosis.


Asunto(s)
Fibrosis , Proteínas de Unión al GTP , Proteína Glutamina Gamma Glutamiltransferasa 2 , Insuficiencia Renal Crónica , Animales , Humanos , Masculino , Conejos , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados/farmacología , Modelos Animales de Enfermedad , Fibrosis/tratamiento farmacológico , Proteínas de Unión al GTP/antagonistas & inhibidores , Proteínas de Unión al GTP/metabolismo , Proteínas de Unión al GTP/inmunología , Riñón/patología , Riñón/efectos de los fármacos , Riñón/metabolismo , Macaca fascicularis , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/patología , Transglutaminasas/antagonistas & inhibidores , Transglutaminasas/metabolismo
5.
Environ Sci Technol ; 58(18): 8020-8031, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38629457

RESUMEN

Cyanobacterial blooms introduce autochthonous dissolved organic matter (DOM) into aquatic environments, but their impact on surface water photoreactivity has not been investigated through collaborative field sampling with comparative laboratory assessments. In this work, we quantified the apparent quantum yields (Φapp,RI) of reactive intermediates (RIs), including excited triplet states of dissolved organic matter (3DOM*), singlet oxygen (1O2), and hydroxyl radicals (•OH), for whole water samples collected by citizen volunteers from more than 100 New York lakes. Multiple comparisons tests and orthogonal partial least-squares analysis identified the level of cyanobacterial chlorophyll a as a key factor in explaining the enhanced photoreactivity of whole water samples sourced from bloom-impacted lakes. Laboratory recultivation of bloom samples in bloom-free lake water demonstrated that apparent increases in Φapp,RI during cyanobacterial growth were likely driven by the production of photoreactive moieties through the heterotrophic transformation of freshly produced labile bloom exudates. Cyanobacterial proliferation also altered the energy distribution of 3DOM* and contributed to the accelerated transformation of protriptyline, a model organic micropollutant susceptible to photosensitized reactions, under simulated sunlight conditions. Overall, our study provides insights into the relationship between the photoreactivity of surface waters and the limnological characteristics and trophic state of lakes and highlights the relevance of cyanobacterial abundance in predicting the photoreactivity of bloom-impacted surface waters.


Asunto(s)
Cianobacterias , Lagos , Lagos/microbiología , New York , Eutrofización , Monitoreo del Ambiente
6.
Evolution ; 78(5): 894-905, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38315570

RESUMEN

Diverse clades of fishes adapted to feeding on the benthos repeatedly converge on steep craniofacial profiles and shorter, wider heads. But in an incipient radiation, to what extent is this morphological evolution measurable and can we distinguish the relative genetic vs. plastic effects? We use the Trinidadian guppy (Poecilia reticulata) to test the repeatability of adaptation and the alignment of genetic and environmental effects shaping poecilid craniofacial morphology. We compare wild-caught and common garden lab-reared fish to quantify the genetic and plastic components of craniofacial morphology across 4 populations from 2 river drainage systems (n = 56 total). We first use micro-computed tomography to capture 3D morphology, then place both landmarks and semilandmarks to perform size-corrected 3D morphometrics and quantify shape space. We find a measurable, significant, and repeatable divergence in craniofacial shape between high-predation invertivore and low-predation detritivore populations. As predicted from previous examples of piscine adaptive trophic divergence, we find increases in head slope and craniofacial compression among the benthic detritivore foragers. Furthermore, the effects of environmental plasticity among benthic detritivores produce exaggerated craniofacial morphological change along a parallel axis to genetic morphological adaptation from invertivore ancestors. Overall, many of the major patterns of benthic-limnetic craniofacial evolution appear convergent among disparate groups of teleost fishes.


Asunto(s)
Evolución Biológica , Poecilia , Cráneo , Animales , Poecilia/anatomía & histología , Poecilia/genética , Poecilia/fisiología , Cráneo/anatomía & histología , Microtomografía por Rayos X , Cadena Alimentaria , Conducta Predatoria
7.
J Biol Chem ; 300(3): 105747, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38354783

RESUMEN

Glycosyltransferases (GT) catalyze the glycosylation of bioactive natural products, including peptides and proteins, flavonoids, and sterols, and have been extensively used as biocatalysts to generate glycosides. However, the often narrow substrate specificity of wild-type GTs requires engineering strategies to expand it. The GT-B structural family is constituted by GTs that share a highly conserved tertiary structure in which the sugar donor and acceptor substrates bind in dedicated domains. Here, we have used this selective binding feature to design an engineering process to generate chimeric glycosyltransferases that combine auto-assembled domains from two different GT-B enzymes. Our approach enabled the generation of a stable dimer with broader substrate promiscuity than the parent enzymes that were related to relaxed interactions between domains in the dimeric GT-B. Our findings provide a basis for the development of a novel class of heterodimeric GTs with improved substrate promiscuity for applications in biotechnology and natural product synthesis.


Asunto(s)
Biocatálisis , Glicosiltransferasas , Flavonoides/química , Glicosilación , Glicosiltransferasas/química , Glicosiltransferasas/genética , Especificidad por Sustrato , Dominios Proteicos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Bioingeniería/métodos
8.
iScience ; 27(1): 108763, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38261926

RESUMEN

Respiratory syncytial virus (RSV) is a global healthcare problem, causing respiratory illness in young children and elderly individuals. Our knowledge of the host pathways that define susceptibility to infection and disease severity are limited. Hypoxia inducible factors (HIFs) define metabolic responses to low oxygen and regulate inflammatory responses in the lower respiratory tract. We demonstrate a role for HIFs to suppress RSV entry and RNA replication. We show that hypoxia and HIF prolyl-hydroxylase inhibitors reduce the expression of the RSV entry receptor nucleolin and inhibit viral cell-cell fusion. We identify a HIF regulated microRNA, miR-494, that regulates nucleolin expression. In RSV-infected mice, treatment with the clinically approved HIF prolyl-hydroxylase inhibitor, Daprodustat, reduced the level of infectious virus and infiltrating monocytes and neutrophils in the lung. This study highlights a role for HIF-signalling to limit multiple aspects of RSV infection and associated inflammation and informs future therapeutic approaches for this respiratory pathogen.

9.
J Biomech ; 163: 111949, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38281459

RESUMEN

Successful osseointegration of press-fit implants depends on the initial stability, often measured by the micromotions between the implant and bone. A good primary stability can be achieved by optimizing the compressive and frictional forces acting at the bone-implant interface. The frictional properties of the implant-bone interface, which depend on the roughness and porosity of the implant surface coating, can affect the primary stability. Several reversible (elastic) and non-reversible (permanent) deformation processes take place during frictional loading of the implant-bone interface. In case of a rough coating, the asperities of the implant surface are compressed into the bone leading to mechanical interlocking. To optimize fixation of orthopaedic implants it is crucial to understand these complex interactions between coating and bone. The objective of the current study was to gain more insight into the reversible and non-reversible processes acting at the implant-bone interface. Tribological experiments were performed with two types of porous coatings against human cadaveric bone. The results indicated that the coefficient of friction depended on the coating roughness (0.86, 0.95, and 0.45 for an Ra roughness of 41.2, 53.0, and a polished surface, respectively). Larger elastic and permanent displacements were found for the rougher coating, resulting in a lower interface stiffness. The experiments furthermore revealed that relative displacements of up to 35 µm can occur without sliding at the interface. These findings have implications for micromotion thresholds that currently are assumed for osseointegration, and suggest that bone ingrowth actually occurs in the absence of relative sliding at the implant-bone interface.


Asunto(s)
Oseointegración , Prótesis e Implantes , Humanos , Huesos , Interfase Hueso-Implante
10.
J Virol ; 97(11): e0042423, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37929963

RESUMEN

IMPORTANCE: SARS-CoV-2 has caused a worldwide health and economic crisis. During the course of the pandemic, genetic changes occurred in the virus, which have resulted in new properties of the virus-particularly around gains in transmission and the ability to partially evade either natural or vaccine-acquired immunity. Some of these viruses have been labeled Variants of Concern (VoCs). At the root of all VoCs are two mutations, one in the viral spike protein that has been very well characterized and the other in the virus polymerase (NSP12). This is the viral protein responsible for replicating the genome. We show that NSP12 associates with host cell proteins that act as a scaffold to facilitate the function of this protein. Furthermore, we found that different variants of NSP12 interact with host cell proteins in subtle and different ways, which affect function.


Asunto(s)
COVID-19 , ARN Polimerasa Dependiente de ARN de Coronavirus , Proteína 2 con Dominio MARVEL , SARS-CoV-2 , Humanos , Inmunidad Adaptativa , COVID-19/virología , Citosol , Mutación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , ARN Polimerasa Dependiente de ARN de Coronavirus/genética , Proteína 2 con Dominio MARVEL/genética
11.
J Exp Biol ; 226(23)2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37947155

RESUMEN

The vertebrate immune system provides an impressively effective defense against parasites and pathogens. However, these benefits must be balanced against a range of costly side-effects including energy loss and risks of auto-immunity. These costs might include biomechanical impairment of movement, but little is known about the intersection between immunity and biomechanics. Here, we show that a fibrosis immune response to Schistocephalus solidus infection in freshwater threespine stickleback (Gasterosteus aculeatus) has collateral effects on their locomotion. Although fibrosis is effective at reducing infection, some populations of stickleback actively suppress this immune response, possibly because the costs of fibrosis outweigh the benefits. We quantified the locomotor effects of the fibrosis immune response in the absence of parasites to investigate whether there are incidental costs of fibrosis that could help explain why some fish forego this effective defense. To do this, we induced fibrosis in stickleback and then tested their C-start escape performance. Additionally, we measured the severity of fibrosis, body stiffness and body curvature during the escape response. We were able to estimate performance costs of fibrosis by including these variables as intermediates in a structural equation model. This model revealed that among control fish without fibrosis, there is a performance cost associated with increased body stiffness. However, fish with fibrosis did not experience this cost but rather displayed increased performance with higher fibrosis severity. This result demonstrates that the adaptive landscape of immune responses can be complex with the potential for wide-reaching and unexpected fitness consequences.


Asunto(s)
Cestodos , Infecciones por Cestodos , Enfermedades de los Peces , Parásitos , Smegmamorpha , Animales , Enfermedades de los Peces/parasitología , Peces , Cestodos/fisiología , Inmunidad , Interacciones Huésped-Parásitos , Infecciones por Cestodos/parasitología
12.
Proc Natl Acad Sci U S A ; 120(41): e2305180120, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37788314

RESUMEN

Robots are notoriously difficult to design because of complex interdependencies between their physical structure, sensory and motor layouts, and behavior. Despite this, almost every detail of every robot built to date has been manually determined by a human designer after several months or years of iterative ideation, prototyping, and testing. Inspired by evolutionary design in nature, the automated design of robots using evolutionary algorithms has been attempted for two decades, but it too remains inefficient: days of supercomputing are required to design robots in simulation that, when manufactured, exhibit desired behavior. Here we show de novo optimization of a robot's structure to exhibit a desired behavior, within seconds on a single consumer-grade computer, and the manufactured robot's retention of that behavior. Unlike other gradient-based robot design methods, this algorithm does not presuppose any particular anatomical form; starting instead from a randomly-generated apodous body plan, it consistently discovers legged locomotion, the most efficient known form of terrestrial movement. If combined with automated fabrication and scaled up to more challenging tasks, this advance promises near-instantaneous design, manufacture, and deployment of unique and useful machines for medical, environmental, vehicular, and space-based tasks.

13.
iScience ; 26(11): 108080, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37860693

RESUMEN

The SARS-CoV-2 genome encodes a multitude of accessory proteins. Using comparative genomic approaches, an additional accessory protein, ORF3c, has been predicted to be encoded within the ORF3a sgmRNA. Expression of ORF3c during infection has been confirmed independently by ribosome profiling. Despite ORF3c also being present in the 2002-2003 SARS-CoV, its function has remained unexplored. Here we show that ORF3c localizes to mitochondria, where it inhibits innate immunity by restricting IFN-ß production, but not NF-κB activation or JAK-STAT signaling downstream of type I IFN stimulation. We find that ORF3c is inhibitory after stimulation with cytoplasmic RNA helicases RIG-I or MDA5 or adaptor protein MAVS, but not after TRIF, TBK1 or phospho-IRF3 stimulation. ORF3c co-immunoprecipitates with the antiviral proteins MAVS and PGAM5 and induces MAVS cleavage by caspase-3. Together, these data provide insight into an uncharacterized mechanism of innate immune evasion by this important human pathogen.

14.
Diabetes Obes Metab ; 25(10): 3020-3029, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37435776

RESUMEN

AIM: To explore whether the beneficial cardiovascular (CV) effect of sodium-glucose co-transporter-2 (SGLT-2) inhibitors is consistent with or without concurrent use of CV medications in patients with type 2 diabetes, heart failure (HF) or chronic kidney disease. METHODS: We searched Medline and Embase up to September 2022 for CV outcomes trials. The primary endpoint was the composite of cardiovascular (CV) death or hospitalization for HF. Secondary outcomes included the individual components of CV death, hospitalization for HF, death from any cause, major adverse CV events or renal events, volume depletion and hyperkalaemia. We pooled hazard ratios (HRs) and risk ratios alongside 95% confidence intervals (CIs). RESULTS: We included 12 trials comprising 83 804 patients. SGLT-2 inhibitors reduced the risk of CV death or hospitalization for HF regardless of background use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACEIs/ARBs), angiotensin receptor-neprilysin inhibitors (ARNIs), b-blockers, diuretics, mineralocorticoid receptor antagonists (MRAs), or triple combination therapy of either an ACEI/ARB plus b-blocker plus MRA, or an ARNI plus b-blocker plus MRA (HRs ranged from 0.61 to 0.83; P > .1 for each subgroup interaction). Similarly, no subgroup differences were evident for most analyses for the secondary outcomes of CV death, hospitalization for HF, all-cause mortality, major adverse CV or renal events, hyperkalaemia and volume depletion rate. CONCLUSIONS: The benefit of SGLT-2 inhibitors seems to be additive to background use of CV medications in a broad population of patients. These findings should be interpreted as hypothesis generating because most of the subgroups analysed were not prespecified.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Insuficiencia Cardíaca , Hiperpotasemia , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Simportadores , Humanos , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Insuficiencia Cardíaca/complicaciones , Simportadores/uso terapéutico , Glucosa/uso terapéutico , Sodio , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/complicaciones
15.
PLoS One ; 18(7): e0288259, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37459326

RESUMEN

Human epidermal growth factor receptor-2 (HER2) is a well-recognised biomarker associated with 25% of breast cancers. In most cases, early detection and/or treatment correlates with an increased chance of survival. This study, has identified and characterised a highly specific anti-HER2 single-domain antibody (sdAb), NM-02, as a potential theranostic tool. Complete structural description by X-ray crystallography has revealed a non-overlapping epitope with current anti-HER2 antibodies. To reduce the immunogenicity risk, NM-02 underwent a humanisation process and retained wild type-like binding properties. To further de-risk the progression towards chemistry, manufacturing and control (CMC) we performed full developability profiling revealing favourable thermal and physical biochemical 'drug-like' properties. Finally, the application of the lead humanised NM-02 candidate (variant K) for HER2-specific imaging purposes was demonstrated using breast cancer HER2+/BT474 xenograft mice.


Asunto(s)
Neoplasias de la Mama , Anticuerpos de Dominio Único , Humanos , Ratones , Animales , Femenino , Anticuerpos de Dominio Único/química , Medicina de Precisión , Receptor ErbB-2/metabolismo , Neoplasias de la Mama/metabolismo , Anticuerpos , Línea Celular Tumoral
16.
Integr Comp Biol ; 63(3): 843-859, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37422435

RESUMEN

To understand the complexities of morphological evolution, we must understand the relationships between genes, morphology, performance, and fitness in complex traits. Genomicists have made tremendous progress in finding the genetic basis of many phenotypes, including a myriad of morphological characters. Similarly, field biologists have greatly advanced our understanding of the relationship between performance and fitness in natural populations. However, the connection from morphology to performance has primarily been studied at the interspecific level, meaning that in most cases we lack a mechanistic understanding of how evolutionarily relevant variation among individuals affects organismal performance. Therefore, functional morphologists need methods that will allow for the analysis of fine-grained intraspecific variation in order to close the path from genes to fitness. We suggest three methodological areas that we believe are well suited for this research program and provide examples of how each can be applied within fish model systems to build our understanding of microevolutionary processes. Specifically, we believe that structural equation modeling, biological robotics, and simultaneous multi-modal functional data acquisition will open up fruitful collaborations among biomechanists, evolutionary biologists, and field biologists. It is only through the combined efforts of all three fields that we will understand the connection between evolution (acting at the level of genes) and natural selection (acting on fitness).


Asunto(s)
Evolución Biológica , Condicionamiento Físico Animal , Animales , Selección Genética , Fenotipo , Peces
17.
Vaccines (Basel) ; 11(7)2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37515003

RESUMEN

We develop candidate HIV-1 vaccines, of which two components, ChAdOx1.tHIVconsv1 (C1) and ChAdOx1.HIVconsv62 (C62), are delivered by the simian adenovirus-derived vaccine vector ChAdOx1. Aberrant adenovirus RNA splicing involving transgene(s) coding for the SARS-CoV-2 spike was suggested as an aetiology of rare adverse events temporarily associated with the initial deployment of adenovirus-vectored vaccines during the COVID-19 pandemic. Here, to eliminate this theoretically plausible splicing phenomenon from the list of possible pathomechanisms for our HIV-1 vaccine candidates, we directly sequenced mRNAs in C1- and C62-infected nonpermissive MRC-5 and A549 and permissive HEK293 human cell lines. Our two main observations in nonpermissive human cells, which are most similar to those which become infected after the intramuscular administration of vaccines into human volunteers, were that (i) the dominant adenovirus vector-derived mRNAs were the expected transcripts coding for the HIVconsvX immunogens and (ii) atypical splicing events within the synthetic open reading frame of the two transgenes are rare. We conclude that inadvertent RNA splicing is not a safety concern for the two tested candidate HIV-1 vaccines.

18.
bioRxiv ; 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37425734

RESUMEN

The vertebrate immune system provides an impressively effective defense against parasites and pathogens. However, these benefits must be balanced against a range of costly side-effects including energy loss and risks of auto-immunity. These costs might include biomechanical impairment of movement, but little is known about the intersection between immunity and biomechanics. Here, we show that a fibrosis immune response in threespine stickleback (Gasterosteus aculeatus) has collateral effects on their locomotion. When freshwater stickleback are infected with the tapeworm parasite Schistocephalus solidus, they face an array of fitness consequences ranging from impaired body condition and fertility to an increased risk of mortality. To fight the infection, some stickleback will initiate a fibrosis immune response in which they produce excess collagenous tissue in their coelom. Although fibrosis is effective at reducing infection, some populations of stickleback actively suppress this immune response, possibly because the costs of fibrosis outweigh the benefits. Here we quantify the locomotor effects of the fibrosis immune response in the absence of parasites to investigate whether there are collateral costs of fibrosis that could help explain why some fish forego this effective defense. To do this, we induce fibrosis in stickleback and then test their C-start escape performance. Additionally, we measure the severity of fibrosis, body stiffness, and body curvature during the escape response. We were able to estimate performance costs of fibrosis by including these variables as intermediates in a structural equation model. This model reveals that among control fish without fibrosis, there is a performance cost associated with increased body stiffness. However, fish with fibrosis did not experience this cost but rather displayed increased performance with higher fibrosis severity. This result demonstrates that the adaptive landscape of immune responses can be complex with the potential for wide reaching and unexpected fitness consequences.

19.
J Biol Chem ; 299(6): 104740, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37088134

RESUMEN

Plexin-B1 is a receptor for the cell surface semaphorin, Sema4D. This signaling system has been implicated in a variety of human diseases, including cancer, multiple sclerosis and osteoporosis. While inhibitors of the Plexin-B1:Sema4D interaction have been previously reported, understanding their mechanism has been hindered by an incomplete structural view of Plexin-B1. In this study, we have raised and characterized a pair of nanobodies that are specific for mouse Plexin-B1 and which inhibit the binding of Sema4D to mouse Plexin-B1 and its biological activity. Structural studies of these nanobodies reveal that they inhibit the binding of Sema4D in an allosteric manner, binding to epitopes not previously reported. In addition, we report the first unbound structure of human Plexin-B1, which reveals that Plexin-B1 undergoes a conformational change on Sema4D binding. These changes mirror those seen upon binding of allosteric peptide modulators, which suggests a new model for understanding Plexin-B1 signaling and provides a potential innovative route for therapeutic modulation of Plexin-B1.


Asunto(s)
Moléculas de Adhesión Celular , Semaforinas , Anticuerpos de Dominio Único , Animales , Ratones , Receptores de Superficie Celular/metabolismo , Semaforinas/metabolismo , Transducción de Señal , Moléculas de Adhesión Celular/metabolismo
20.
Genome Biol ; 24(1): 47, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36915185

RESUMEN

BACKGROUND: The mutational landscape of SARS-CoV-2 varies at the dominant viral genome sequence and minor genomic variant population. During the COVID-19 pandemic, an early substitution in the genome was the D614G change in the spike protein, associated with an increase in transmissibility. Genomes with D614G are accompanied by a P323L substitution in the viral polymerase (NSP12). However, P323L is not thought to be under strong selective pressure. RESULTS: Investigation of P323L/D614G substitutions in the population shows rapid emergence during the containment phase and early surge phase during the first wave. These substitutions emerge from minor genomic variants which become dominant viral genome sequence. This is investigated in vivo and in vitro using SARS-CoV-2 with P323 and D614 in the dominant genome sequence and L323 and G614 in the minor variant population. During infection, there is rapid selection of L323 into the dominant viral genome sequence but not G614. Reverse genetics is used to create two viruses (either P323 or L323) with the same genetic background. L323 shows greater abundance of viral RNA and proteins and a smaller plaque morphology than P323. CONCLUSIONS: These data suggest that P323L is an important contribution in the emergence of variants with transmission advantages. Sequence analysis of viral populations suggests it may be possible to predict the emergence of a new variant based on tracking the frequency of minor variant genomes. The ability to predict an emerging variant of SARS-CoV-2 in the global landscape may aid in the evaluation of medical countermeasures and non-pharmaceutical interventions.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Pandemias , Antecedentes Genéticos , Genoma Viral , Mutación
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