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Perry, J. L.

Publications and source records attributed to Perry, J. L..

10 recordsLinked to original sources

Development of fluorescent and affinity tagged variants of rotavirus nonstructural protein 4 using the reverse genetics system

Rotavirus (RV) nonstructural protein 4 (NSP4) is a multifunctional viroporin and enterotoxin that also serves an essential structural role in virion assembly, making it both a central virulence factor and a potential therapeutic target. However, studying NSP4 within infectious virus has been hindered by essential RNA packaging signals at the 5' end of gene segment 10 (gs10) and an DLP-binding domain at its C-terminus, both of which constrain conventional mutagenesis. Using a plasmid-based reverse genetics system, we generated six recombinant rotaviruses (rRVs) encoding tagged or reporter-fused NSP4 via three strategies: expression from an alternative segment (gs7) in a bicistronic arrangement, N-terminal tagging of gs10 with translation shifted downstream of the native packaging sequence, and retention of the gs10 5' UTR and fusion of the first 20 amino acids fused to a reporter followed by bicistronic full-length NSP4 expression. All six rRVs were replication competent, with gs10-based constructs closely matching wild-type replication kinetics while gs7-based constructs showed modest attenuation and, in one case, genetic instability upon passage. Engineered NSP4 proteins were robustly expressed, correctly glycosylated, and capable of oligomerization. Live-cell imaging showed reporter fluorescence reliably tracked NSP4 synthesis and preceded NSP4-dependent intercellular calcium signals. Affinity purification of tagged NSP4 recovered viroplasm-associated and structural viral proteins along with candidate host interactors, including ANP32A, ANP32E, PPM1G, and H2AC1. These rRVs constitute a validated toolkit for dissecting NSP4 function during bona fide infection and establish a generalizable strategy for engineering constrained rotavirus gene segments.

microbiology↗

Free-Form Microfluidic Microneedle Array Patches

Personalized biomedical devices, such as microneedle array patches (MAPs), offer a promising transdermal drug delivery technology, providing a safe, painless, and self- administered alternative to traditional hypodermic injections. Despite their potential for precise therapeutic release, MAP adoption has been limited by challenges in payload capacity, treatment versatility, and manufacturing scalability. To address these issues, we integrated microfluidic channel designs with MAP technology, enhancing its functionality for delivering a range of payloads, from liquid therapeutics to solid-state cargos, at tunable volumes. Using injection continuous liquid interface production (iCLIP), a novel additive manufacturing approach, we fabricated high-resolution microfluidic MAPs with complex designs. Inspired by the stingers and fangs of various venomous animals, we developed a biomimetic microneedle design that prevents clogging, enhances mechanical strength, and eliminates needle leakage, thereby improving therapeutic delivery efficiency. Our technology reliably delivers multiple distinct payloads, enables combinational mixing, and enables point-of-care reconstitution of solid-state payloads. TeaserLeveraging biomimetic design and advanced 3D printing, we developed high-resolution microfluidic microneedle array patches (MAPs) that overcome payload and scalability challenges, offering a versatile and efficient platform for precise transdermal drug delivery.

bioengineering↗

Suppression of progesterone by influenza A virus causes adverse maternal and fetal outcomes in mice

Influenza A virus infection during pregnancy can cause adverse maternal and fetal outcomes, but the mechanism responsible remains elusive. Infection of outbred mice with 2009 H1N1 at embryonic day (E) 10 resulted in significant maternal morbidity, placental tissue damage and inflammation, fetal growth restriction, and developmental delays that lasted through weaning. Restriction of pulmonary virus replication was not inhibited during pregnancy, but infected dams had suppressed circulating and placental progesterone (P4) concentrations that were caused by H1N1-induced upregulation of pulmonary cyclooxygenase (COX)-1, but not COX-2-, dependent synthesis and secretion of prostaglandin (PG) F2. Treatment with 17--hydroxyprogesterone caproate (17-OHPC), a synthetic progestin that is safe to use in pregnancy, ameliorated the adverse maternal and fetal outcomes from H1N1 infection and prevented placental cell death and inflammation. These findings highlight the therapeutic potential of progestin treatments for influenza during pregnancy. ImportancePregnant individuals are at risk of severe outcomes from both seasonal and pandemic influenza A viruses. Influenza infection during pregnancy is associated with adverse fetal outcomes at birth and adverse consequences for offspring into adulthood. We developed an outbred mouse model of 2009 H1N1 influenza virus infection during pregnancy, with semi-allogenic fetuses. When dams are infected with 2009 H1N1, in addition to pulmonary virus replication, tissue damage, and inflammation, the placenta shows evidence of transient damage and inflammation that is mediated by increased activity along the arachidonic acid pathway leading to suppression of circulating progesterone. Placental damage and suppressed progesterone are associated with long-term effects on perinatal growth and developmental delays in offspring. Treatment of H1N1-infected pregnant mice with 17-OHPC, a synthetic progestin treatment safe that is safe to use in pregnancy, prevents placental damage and inflammation and adverse fetal outcomes. This provided a novel therapeutic option for treatment of influenza during pregnancy that should be explored clinically.

microbiology↗

The Inositol Trisphosphate Receptor (IP3R) is Dispensable for Rotavirus-induced Ca2+ Signaling and Replication but Critical for Paracrine Ca2+ Signals that Prime Uninfected Cells for Rapid Virus Spread

Rotavirus is a leading cause of viral gastroenteritis. A hallmark of rotavirus infection is an increase in cytosolic Ca2+ caused by the nonstructural protein 4 (NSP4). NSP4 is a viral ion channel that releases Ca2+ from the endoplasmic reticulum (ER) and the increase in Ca2+ signaling is critical for rotavirus replication. In addition to NSP4 itself, host inositol 1,4,5- trisphosphate receptor (IP3R) ER Ca2+ channels may contribute to rotavirus-induced Ca2+ signaling and by extension, virus replication. Thus, we set out to determine the role of IP3R Ca2+ signaling during rotavirus infection using IP3R-knockout MA104-GCaMP6s cells (MA104- GCaMP6s-IP3R-KO), generated by CRISPR/Cas9 genome editing. Live Ca2+ imaging showed that IP3R-KO did not reduce Ca2+ signaling in infected cells but eliminated rotavirus-induced intercellular Ca2+ waves (ICWs) and therefore the increased Ca2+ signaling in surrounding, uninfected cells. Further, MA104-GCaMP6s-IP3R-TKO cells showed similar rotavirus susceptibility, single-cycle replication, and viral protein expression as parental MA104- GCaMP6s cells. However, MA104-GCaMP6s-IP3R-TKO cells exhibited significantly smaller rotavirus plaques, decreased multi-round replication kinetics, and delayed virus spread, suggesting that rotavirus-induced ICW Ca2+ signaling stimulates virus replication and spread. Inhibition of ICWs by blocking the P2Y1 receptor also resulted in decreased rotavirus plaque size. Conversely, exogenous expression of P2Y1 in LLC-MK2-GCaMP6s cells, which natively lack P2Y1 and rotavirus ICWs, rescued the generation of rotavirus-induced ICWs and enabled plaque formation. In conclusion, this study shows that NSP4 Ca2+ signals fully support rotavirus replication in individual cells; however, IP3R is critical for rotavirus-induced ICWs and virus spread by priming Ca2+-dependent pathways in surrounding cells. ImportanceMany viruses exploit host Ca2+ signaling to facilitate their replication; however, little is known about how distinct types of Ca2+ signals contribute to the overall dysregulation of Ca2+ signaling or promote virus replication. Using cells lacking IP3R, a host ER Ca2+ channel, we could differentiate between intracellular Ca2+ signals within virus-infected cells and intercellular Ca2+ waves (ICWs), which increase Ca2+ signaling in neighboring, uninfected cells. In infected cells, IP3R was dispensable for rotavirus-induced Ca2+ signaling and replication, suggesting the rotavirus NSP4 viroporin supplies these signals. However, IP3R-mediated ICWs increase rotavirus replication kinetics and spread, indicating that the Ca2+ signals from the ICWs may prime nearby uninfected cells to better support virus replication upon eventual infection. This "pre-emptive priming" of uninfected cells by exploiting host intercellular pathways in the vicinity of virus-infected cells represents a novel mechanism for viral reprogramming of the host to gain a replication advantage.

microbiology↗

Adverse outcomes in SARS-CoV-2 infected pregnant mice are gestational age-dependent and resolve with antiviral treatment

SARS-CoV-2 infection during pregnancy is associated with severe COVID-19 and adverse fetal outcomes, but the underlying mechanisms remain poorly understood. Moreover, clinical studies assessing therapeutics against SARS-CoV-2 in pregnancy are limited. To address these gaps, we developed a mouse model of SARS-CoV-2 infection during pregnancy. Outbred CD1 mice were infected at embryonic day (E) 6, E10, or E16 with a mouse adapted SARS-CoV-2 (maSCV2) virus. Outcomes were gestational age-dependent, with greater morbidity, reduced anti-viral immunity, greater viral titers, and more adverse fetal outcomes occurring with infection at E16 (3rd trimester-equivalent) than with infection at either E6 (1st trimester-equivalent) or E10 (2nd trimester-equivalent). To assess the efficacy of ritonavir-boosted nirmatrelvir (recommended for pregnant individuals with COVID-19), we treated E16-infected dams with mouse equivalent doses of nirmatrelvir and ritonavir. Treatment reduced pulmonary viral titers, decreased maternal morbidity, and prevented adverse offspring outcomes. Our results highlight that severe COVID-19 during pregnancy and adverse fetal outcomes are associated with heightened virus replication in maternal lungs. Ritonavir-boosted nirmatrelvir mitigated adverse maternal and fetal outcomes of SARS-CoV-2 infection. These findings prompt the need for further consideration of pregnancy in preclinical and clinical studies of therapeutics against viral infections.

microbiology↗

A bioengineered probiotic for the oral delivery of a peptide Kv1.3 channel blocker to treat rheumatoid arthritis

Engineered microbes for the delivery of biologics is a promising avenue for the treatment of various conditions such as chronic inflammatory disorders and metabolic disease. In this study, we developed a genetically engineered probiotic delivery system that delivers the small molecular biologic to the intestinal tract with high efficacy and minimized side effects. We constructed an inducible system in the probiotic Lactobacillus reuteri to secret functional Kv1.3 potassium blocker ShK-235 (LrS235). We show that LrS235 is capable of blocking Kv1.3 currents and preferentially inhibiting human T effector memory (TEM) cells proliferation in vitro. A single oral gavage of healthy rats with LrS235 resulted in adequate functional ShK-235 in the circulation to reduce inflammation in a delayed-type hypersensitivity model of atopic dermatitis mediated by TEM cells. Furthermore, the daily oral gavage of LrS235 dramatically reduced clinical signs of disease and joint inflammation in rats with a model of rheumatoid arthritis without eliciting immunogenicity against ShK-235. This work demonstrates the efficacy of using probiotic L. reuteri as a novel oral delivery platform for the small molecule ShK-235, and provides a efficacious strategy to deliver other biologics with great translational potential. Significance StatementNew therapeutics that combine efficacy with limited side effects and can be delivered non-invasively are needed to adequately treat patients with rheumatoid arthritis (RA) and other autoimmune diseases. Kv1.3 channel-expressing CCR7- effector memory T (TEM) lymphocytes are significant players in the pathogenesis of multiple autoimmune diseases and blocking Kv1.3 reduces disease severity in rat models of RA and patients with plaque psoriasis. However, peptide therapeutics require repeated injections, reducing patient compliance. We used a bioengineered Lactobacillus reuteri as an oral delivery method of a Kv1.3 blocker for immunomodulation in rat models of atopic dermatitis and RA. This study demonstrates a novel approach for the non-invasive delivery of peptide-based therapeutics for the oral treatment of chronic inflammatory diseases.

synthetic biology↗

ROTAVIRUS INDUCES INTERCELLULAR CALCIUM WAVES THROUGH ADP SIGNALING

Rotavirus causes severe diarrheal disease in children by broadly dysregulating intestinal homeostasis. However, the underlying mechanism(s) of rotavirus-induced dysregulation remains incompletely characterized. Here we show that rotavirus-infected cells produce paracrine signals that manifest as intercellular calcium waves (ICWs); which are observed in both cell lines and human intestinal enteroids. Rotavirus ICWs are caused by the release of extracellular adenosine diphosphate (ADP) that activates P2Y1 purinergic receptors on neighboring cells and are blocked by P2Y1 antagonists or CRISPR/Cas9 knockout of P2Y1. Blocking the paracrine ADP signal reduces rotavirus replication, inhibits rotavirus-induced serotonin release and fluid secretion, and reduces diarrhea severity in neonatal mice. This is the first evidence that viruses exploit ICWs to amplify diarrheal signaling; a finding which has broad implications for gastrointestinal physiology. SummaryRotavirus triggers the extracellular release of ADP from infected cells to dysregulate nearby uninfected cells and activate pro-disease pathways.

microbiology↗

Recovirus NS1-2 has viroporin activity that induces aberrant cellular calcium signaling to facilitate virus replication

Enteric viruses in the Caliciviridae family cause acute gastroenteritis in humans and animals, but the cellular processes needed for virus replication and disease remain unknown. A common strategy among enteric viruses, including rotaviruses and enteroviruses, is to encode a viral ion channel (i.e., viroporin) that is targeted to the endoplasmic reticulum (ER) and disrupts host calcium (Ca2+) homeostasis. Previous reports have demonstrated genetic and functional similarities between the nonstructural proteins of caliciviruses and enteroviruses, including the calicivirus NS1-2 protein and the 2B viroporin of enteroviruses. However, it is unknown whether caliciviruses alter Ca2+ homeostasis for virus replication or whether the NS1-2 protein has viroporin activity like its enterovirus counterpart. To address these questions, we used Tulane virus (TV), a rhesus enteric calicivirus, to examine Ca2+ signaling during infection and determine whether NS1-2 has viroporin activity that disrupts Ca2+ homeostasis. We found that TV disrupts increases Ca2+ signaling during infection and increased cytoplasmic Ca2+ levels is important for efficient replication. Further, TV NS1-2 localizes to the endoplasmic reticulum (ER), the predominant intracellular Ca2+ store and the NS2 region has characteristics of a viroporin domain (VPD). NS1-2 had viroporin activity in a classic bacterial functional assay and caused aberrant Ca2+ signaling when expressed in mammalian cells, but truncation of the VPD abrogated these functions. Together, our data provide new mechanistic insights into the function of the NS2 region of NS1-2 and show that like many other enteric viruses, enteric caliciviruses also exploit host Ca2+ signaling to facilitate their replication.\n\nImportanceTulane virus is one of many enteric caliciviruses that cause acute gastroenteritis and diarrheal disease. Globally, enteric caliciviruses affect both humans and animals and result in >65 billion dollars per year in treatment and healthcare-associated costs, thus imposing an enormous economic burden. Recent progress has resulted in several cultivation systems (B cell, enteroid and zebrafish larvae) to study human noroviruses, but mechanistic insights into the viral factors and host pathways important for enteric calicivirus replication and infection are largely still lacking. Here we used Tulane virus, a calicivirus that is biologically similar to human noroviruses and can be cultivated in conventional cell culture, to identify and functionally validate NS1-2 as an enteric calicivirus viroporin. Viroporin-mediated calcium signaling may be a broadly utilized pathway for enteric virus replication, and its existence within caliciviruses provides a novel approach to developing antivirals and comprehensive therapeutics for enteric calicivirus diarrheal disease outbreaks.

microbiology↗

Rotavirus Calcium Dysregulation Manifests as Dynamic Calcium Signaling in the Cytoplasm and Endoplasmic Reticulum

Like many viruses, rotavirus (RV) dysregulates calcium homeostasis by elevating cytosolic calcium ([Ca2+]cyt) and decreasing endoplasmic reticulum (ER) stores. While an overall, monophasic increase in [Ca2+]cyt during RV infection has been shown, the nature of the RV-induced aberrant calcium signals and how they manifest over time at the single-cell level have not been characterized. Thus, we generated cell lines and human intestinal enteroids (HIEs) stably expressing cytosolic and/or ER-targeted genetically-encoded calcium indicators to characterize calcium signaling throughout RV infection by time-lapse imaging. We found that RV induces highly dynamic [Ca2+]cyt signaling that manifest as hundreds of discrete [Ca2+]cyt spikes, which increase during peak infection. Knockdown of nonstructural protein 4 (NSP4) attenuates the [Ca2+]cyt spikes, consistent with its role in dysregulating calcium homeostasis. RV-induced [Ca2+]cyt spikes were primarily from ER calcium release and were attenuated by inhibiting the store-operated calcium entry (SOCE) channel Orai1. RV-infected HIEs also exhibited prominent [Ca2+]cyt spikes that were attenuated by inhibiting SOCE, underlining the relevance of these [Ca2+]cyt spikes to gastrointestinal physiology and role of SOCE in RV pathophysiology. Thus, our discovery that RV increases [Ca2+]cyt by dynamic Ca2+ signaling, establishes a new, paradigm-shifting understanding of the spatial and temporal complexity of virus-induced Ca2+ signaling.

microbiology↗

Silversword and lobeliad reintroduction linked to landscape restoration on Mauna Loa and Kilauea, and its implications for plant adaptive radiation in Hawaii

The endemic Hawaiian silversword and lobeliad lineages, which are two of the worlds premier examples of plant adaptive radiation, exemplify the severity of the threats confronting the Hawaiian flora, especially the threats posed by alien species. We have implemented collaborative reintroduction efforts with the endangered Ka[u] silversword (Argyroxiphium kauense) and Pele lobeliad (Clermontiapeleana) in Hawaii Volcanoes National Park. The efforts with the Ka[u] silversword have involved rediscovery, helicopter assisted rescue of diminutive remnant founders, managed breeding, outplanting at two sites in the Park of more than 21,000 seedlings deriving from 169 founders, and facilitated achene dispersal following flowering. The efforts with the Pele lobeliad have involved rediscovery, air-layering of remnant founders while suspended on climbing ropes, managed breeding, and outplanting at two sites in the Park of more than 1,000 seedlings (to date) deriving from six of the seven known founders. We have linked the reintroduction efforts to landscape restoration at large scales in the Park and in adjacent State and private lands, thereby increasing the opportunities for substantial population growth and expansion of the Ka[u] silversword and Pele lobeliad in the future. Additionally, we have extended the reintroduction efforts, including the link to landscape restoration, to encompass all other endangered silversword and lobeliad taxa occurring historically on the eastern slopes of Mauna Loa or on K[i]lauea. In so doing, we seek to restore the possibility of adaptive radiation of the silversword and lobeliad lineages going forward, especially on the youngest and most geologically active, and thus perhaps most evolutionarily dynamic, part of the Hawaiian archipelago.\n\nDedicationThis paper celebrates the centennial of Hawaii Volcanoes National Park, which was founded in August 1916.

evolutionary biology↗