Scholarly Works, Biomedical Sciences and Pathobiology

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Evaluation of pharmacokinetics of metoclopramide administered via subcutaneous bolus and intravenous constant rate infusion to adult horses
Brandon, Amy M.; Williams, Jarred M.; Davis, Jen L.; Martin, Emily G.; Capper, Ava M.; Crabtree, Naomi E. (Wiley, 2024-08-01)
Objective: To determine the pharmacokinetics (PK) of metoclopramide administered via intravenous continuous rate infusion (IV CRI) and subcutaneous (SC) bolus and evaluate for gastrointestinal motility and adverse side effects. Study design: Experimental study; randomized, crossover design. Animals: Six healthy adult horses. Methods: Each horse received metoclopramide via IV CRI (0.04 mg/kg/h for 24 h) and SC bolus (0.08 mg/kg once), with >= 1 week washout period between. Plasma was analyzed by UPLC-MS/MS. Compartmental modeling was used to determine PK parameters for each treatment; nonparametric superposition was used to simulate multiple SC bolus regimens. Gastrointestinal motility and evidence of adverse effects were monitored. Results: Tmax (h) for SC bolus was 0.583 +/- 0.204 versus 17.3 +/- 6.41 for IV CRI, while Cmax (ng/mL) was 27.7 +/- 6.38 versus 43.6 +/- 9.97, respectively. AUC (h x ng/mL) was calculated as 902 +/- 189 for 24 h IV CRI versus 244 +/- 37.4 simulated for 0.08 mg/kg SC bolus every 8 h. Simulations revealed similar exposure between groups with administration of 0.96 mg/kg/day SC bolus, divided into three, four, or six doses. SC bolus bioavailability was estimated as 110 +/- 11.5%. No clear trends in motility alteration were identified. No adverse effects were noted. Conclusion: Repeated SC boluses of metoclopramide at 0.08 mg/kg would result in lower total drug exposure and Tmax than IV CRI administration but would be highly bioavailable. Clinical significance: Higher and/or more frequent SC bolus doses are needed to achieve a similar AUC to IV CRI. No adverse effects were noted; however, evaluation of alternative dosing strategies is warranted.
Competitive Binding of Viral Nuclear Localization Signal Peptide and Inhibitor Ligands to Importin-α Nuclear Transport Protein
Delfing, Bryan M.; Laracuente, Xavier E.; Jeffries, William; Luo, Xingyu; Olson, Audrey; Foreman, Kenneth W.; Petruncio, Greg; Lee, Kyung Hyeon; Paige, Mikell; Kehn-Hall, Kylene; Lockhart, Christopher; Klimov, Dmitri K. (American Chemical Society, 2024-06-13)
Venezuelan equine encephalitis virus (VEEV) is a highly virulent pathogen whose nuclear localization signal (NLS) sequence from capsid protein binds to the host importin-alpha transport protein and blocks nuclear import. We studied the molecular mechanisms by which two small ligands, termed I1 and I2, interfere with the binding of VEEV's NLS peptide to importin-alpha protein. To this end, we performed all-atom replica exchange molecular dynamics simulations probing the competitive binding of the VEEV coreNLS peptide and I1 or I2 ligand to the importin-alpha major NLS binding site. As a reference, we used our previous simulations, which examined noncompetitive binding of the coreNLS peptide or the inhibitors to importin-alpha. We found that both inhibitors completely abrogate the native binding of the coreNLS peptide, forcing it to adopt a manifold of nonnative loosely bound poses within the importin-alpha major NLS binding site. Both inhibitors primarily destabilize the native coreNLS binding by masking its amino acids rather than competing with it for binding to importin-alpha. Because I2, in contrast to I1, binds off-site localizing on the edge of the major NLS binding site, it inhibits fewer coreNLS native binding interactions than I1. Structural analysis is supported by computations of the free energies of the coreNLS peptide binding to importin-alpha with or without competition from the inhibitors. Specifically, both inhibitors reduce the free energy gain from coreNLS binding, with I1 causing significantly larger loss than I2. To test our simulations, we performed AlphaScreen experiments measuring IC50 values for both inhibitors. Consistent with in silico results, the IC50 value for I1 was found to be lower than that for I2. We hypothesize that the inhibitory action of I1 and I2 ligands might be specific to the NLS from VEEV's capsid protein.
Paradoxical sex differences in a hamster model of angiotensin II-dependent hypertension and associated renal injury
Ji, Hong; Nascimento, Laura G. d.; Ahn, Jungeun; Kwon, Dong H.; Williams, Gabrielle; Wu, Xie; Speth, Robert C.; Hawks, Seth A.; Duggal, Nisha K.; Saavedra, Juan M.; Sandberg, Kathryn; de Souza, Aline M. A. (2025-11-03)
Background: Biological sex is a critical determinant in cardiovascular and renal disease outcomes. Although angiotensin II (Ang II) infusion is widely used to model hypertension in mice and rats, little is known about its effects in the Syrian hamster, a small rodent increasingly used for translational research. This study aimed to develop a model of chronic Ang II-induced hypertension in Syrian hamsters and investigate sex-specific differences in blood pressure, renal pathology, and components of the renin-angiotensin system (RAS). Methods: Male and female Syrian hamsters (8–9 weeks old) were infused subcutaneously with Ang II (200 ng/kg/min) or saline via osmotic minipumps for four weeks. Mean arterial pressure (MAP) and kidney wet weight were determined on the euthanasia day. The kidneys were analyzed for renal pathology; renal RAS enzymes (ACE and ACE2) were measured by colorimetric assay and qPCR; cytokines (IL-6 and IL-1β) were measured by qPCR; and the angiotensin receptor type 1 (AT1R) was measured by radioligand binding and qPCR. Results: Ang II infusion increased MAP in both sexes but elicited a significantly greater response in females (+ 50 mmHg) than males (+ 27 mmHg, p < 0.005). Female hamsters exhibited pronounced kidney injury, including acute tubular necrosis, glomerular sclerosis, and vascular fibrinoid necrosis, along with a 2-fold increase in kidney weight normalized to body weight. Ang II significantly downregulated renal ACE, ACE2, and AT1R expression and activity in females but not in males. Renal IL-6 and IL-1β mRNA levels were elevated 20-fold and 3.9-fold, respectively, in females, compared to modest increases in males. Conclusions: Female Syrian hamsters exhibit heightened vulnerability to Ang II-induced hypertension and renal damage compared to males, marked by exaggerated blood pressure elevation, enhanced renal inflammation, and suppression of classical RAS components. This novel hamster model provides a unique platform for studying sex-specific mechanisms of hypertension and renal pathology, with translational relevance for subpopulations of women who are at increased risk of Ang II-dependent hypertension-associated renal disease.
The PTP4A3 inhibitor KVX-053 reduces Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) virulence, inflammation, and development of acute lung injury in K18-hACE2 mice
Colunga-Biancatelli, Ruben M. L.; Solopov, Pavel A.; Woodson, Caitlin M.; Allen, Irving C.; Akhrymuk, Ivan; Akhrymuk, Maryna; Heath, Brittany N.; Ivester, Hannah M.; Day, Tierney; Austin, Dan E.; Kehn-Hall, Kylene; Lazo, John S.; Sharlow, Elizabeth R.; Catravas, John D. (2025-10-28)
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused a global health crisis, marked by high transmissibility and virulence. Despite widespread vaccination efforts, effective treatments for COVID-19, particularly for severe cases leading to Acute Respiratory Distress Syndrome (ARDS), remain limited. This study investigates the efficacy of KVX-053, a protein tyrosine phosphatase type IVA (PTP4A3) small molecule inhibitor, in modulating SARS-CoV-2-induced inflammation and lung injury using in vitro cell models and in vivo K18-hACE2 transgenic mice. KVX-053 reduced in vitro pro-inflammatory cytokine expression, including TNFα, CXCL10, and CXCL11, without impacting viral replication or cell viability. K18-hACE2 mice treated with KVX-053 demonstrated marked improvement in clinical scores and reduced histological evidence of lung injury compared to untreated SARS-CoV-2-infected controls. KVX-053 mitigated the activation of key inflammatory mediators in the lung, including NLRP3 inflammasomes, IL-6, and phosphorylated STAT3, effectively curbing the “cytokine storm” associated with severe COVID-19. Importantly, treatment preserved lung parenchymal integrity, reduced edema, and minimized macrophage infiltration. Our findings highlight PTP4A3 as a potential critical regulator of the inflammatory response during SARS-CoV-2 infection. KVX-053, a potent and selective PTP4A3 inhibitor, emerges as a promising host-directed therapeutic strategy for mitigating ARDS and inflammation-driven lung injury in SARS-CoV-2 and potentially other respiratory viral infections. Future studies are required to optimize dosing strategies, elucidate precise molecular mechanisms, and validate these findings in clinical settings.
Immune Evasion by the NSs Protein of Rift Valley Fever Virus: A Viral Houdini Act
Petraccione, Kaylee; Omichinski, James G.; Kehn-Hall, Kylene (MDPI, 2025-10-21)
Rift Valley fever virus (RVFV) is a negative-sense arbovirus that causes several severe diseases, including hemorrhagic fever in ruminants and humans. There are currently no FDA-approved vaccines or therapeutics for RVFV. The viral nonstructural protein NSs acts like a molecular Harry Houdini, the world-famous escape artist, to help the virus evade the host’s innate immune response and serves as the main virulence factor of RVFV. In this review, we discuss the molecular mechanisms by which NSs interacts with multiple factors to modulate host processes, evade the host immune response, and facilitate viral replication. The impact of NSs mutations that cause viral attenuation is also discussed. Understanding the molecular mechanisms by which NSs evades the host innate immune response is crucial for developing novel therapeutics and vaccines targeting RVFV.
Infant Microbiota Communities and Human Milk Oligosaccharide Supplementation Independently and Synergistically Shape Metabolite Production and Immune Responses in Healthy Mice
Tripp, Patricia; Davis, Erin C.; Gurung, Manoj; Rosa, Fernanda; Bode, Lars; Fox, Renee; LeRoith, Tanya; Simecka, Christy; Seppo, Antti E.; Jaurorvinen, Kirsi M.; Yeruva, Laxmi (Elsevier, 2024-09-01)
Background: Multiple studies have demonstrated associations between the early-life gut microbiome and incidence of inflammatory and autoimmune disease in childhood. Although microbial colonization is necessary for proper immune education, it is not well understood at a mechanistic level how specific fi c communities of bacteria promote immune maturation or drive immune dysfunction in infancy. Objectives: In this study, we aimed to assess whether infant microbial communities with different overall structures differentially influence immune and gastrointestinal development in healthy mice. Methods: Germ-free mice were inoculated with fecal slurries from Bifidobacterium fi dobacterium longum subspecies infantis positive (BIP) or B. longum subspecies infantis negative (BIN) breastfed infants; half of the mice in each group were also supplemented with a pool of human milk oligosaccharides (HMOs) for 14 d. Cecal microbiome composition and metabolite production, systemic and mucosal immune outcomes, and intestinal morphology were assessed at the end of the study. Results: The results showed that inoculation with a BIP microbiome results in a remarkably distinct microbial community characterized by higher relative abundances of cecal Clostridium senu stricto, , Ruminococcus gnavus, , Cellulosilyticum sp., and Erysipelatoclostridium sp. The BIP microbiome produced 2-fold higher concentrations of cecal butyrate, promoted branched short-chain fatty acid (SCFA) production, and further modulated serotonin, kynurenine, and indole metabolism relative to BIN mice. Further, the BIP microbiome increased the proportions of innate and adaptive immune cells in spleen, while HMO supplementation increased proliferation of mesenteric lymph node cells to phorbol myristate acetate and lipopolysaccharide and increased serum IgA and IgG concentrations. Conclusions: Different microbiome compositions and HMO supplementation can modulate SCFA and tryptophan metabolism and innate and adaptive immunity in young, healthy mice, with potentially important implications for early childhood health.
Obesity's Unexpected Influence: Reduced Alphavirus Transmission and Altered Immune Activation in the Vector
Rai, Pallavi; Webb, Emily M.; Paulson, Sally L.; Kang, Lin; Weger-Lucarelli, James (Wiley, 2024-11-01)
Chikungunya virus (CHIKV) and Mayaro virus (MAYV) are emerging/re-emerging alphaviruses transmitted by Aedes spp. mosquitoes and responsible for recent disease outbreaks in the Americas. The capacity of these viruses to cause epidemics is frequently associated with increased mosquito transmission, which in turn is governed by virus-host-vector interactions. Although many studies have explored virus-vector interactions, significant gaps remain in understanding how vertebrate host factors influence alphavirus transmission by mosquitoes. We previously showed that obesity, a ubiquitous vertebrate host biological factor, reduces alphavirus transmission potential in mosquitoes. We hypothesized that alphavirus-infected obese bloodmeals altered immune genes and/or pathways in mosquitoes, thereby inhibiting virus transmission. To test this, we conducted RNA sequencing (RNA-seq) and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) on midgut RNA from mosquitoes fed on alphavirus-infected lean and obese mice. This approach aimed to identify potential antiviral or proviral genes and pathways altered in mosquitoes after consuming infected obese bloodmeals. We found upregulation of the Toll pathway and downregulation of several metabolic and other genes in mosquitoes fed on alphavirus-infected obese bloodmeals. Through gene knockdown studies, we demonstrated the antiviral role of Toll pathway and proviral roles of AAEL009965 and fatty acid synthase (FASN) in the transmission of alphaviruses by mosquitoes. Therefore, this study utilized obesity to identify factors influencing alphavirus transmission by mosquitoes and this research approach may pave the way for designing broadly effective antiviral measures to combat mosquito-borne viruses, such as releasing transgenic mosquitoes deficient in the identified genes.
Dietary prevention of antibiotic-induced dysbiosis and mortality upon aging in mice
Smith, Kelsey M.; Francisco, Sarah G.; Zhu, Ying; Leroith, Tanya; Davis, Meredith L.; Crott, Jimmy W.; Barger, Kathryn; Greenberg, Andrew S.; Smith, Donald E.; Taylor, Allen; Yeruva, Laxmi; Rowan, Sheldon (Wiley, 2024-12-15)
Oral antibiotic use is both widespread and frequent in older adults and has been linked to dysbiosis of the gut microbiota, enteric infection, and chronic diseases. Diet and nutrients, particularly prebiotics, may modify the susceptibility of the gut microbiome to antibiotic-induced dysbiosis. We fed 12-month-old mice a high glycemic (HG) or low glycemic (LG) diet with or without antibiotics (ampicillin and neomycin) for an additional 11 months. The glycemic index was modulated by the ratio of rapidly digested amylopectin starch to slowly digested amylose, a type-2-resistant starch. We observed a significant decrease in survival of mice fed a HG diet containing antibiotics (HGAbx) relative to those fed a LG diet containing antibiotics (LGAbx). HGAbx mice died with an enlarged and hemorrhagic cecum, which is associated with colonic hyperplasia and goblet cell depletion. Gut microbiome analysis revealed a pronounced expansion of Proteobacteria and a near-complete loss of Bacteroidota and Firmicutes commensal bacteria in HGAbx, whereas the LGAbx group maintained a population of Bacteroides and more closely resembled the LG microbiome. The predicted functional capacity for bile salt hydrolase activity was lost in HGAbx mice but retained in LGAbx mice. An LG diet containing amylose may therefore be a potential therapeutic to prevent antibiotic-induced dysbiosis and morbidity.
Degradation of the α-Carboxyl Terminus 11 Peptide: In Vivo and Ex Vivo Impacts of Time, Temperature, Inhibitors, and Gender in Rat
Tasdemiroglu, Yagmur; Council-Troche, McAlister; Chen, Miao; Ledford, Benjamin; Norris, Russell A.; Poelzing, Steven; Gourdie, Robert G.; He, Jia-Qiang (American Chemical Society, 2024-04-22)
In previous research, a synthetic α-carboxyl terminus 1 (αCT1) peptide derived from connexin 43 (Cx43) and its variant (αCT11) showed beneficial effects in an ex vivo ischemia-reperfusion (I/R) heart injury model in mouse. In an in vivo mouse model of cryo-induced ventricular injury, αCT1 released from adhesive cardiac patches reduced Cx43 remodeling and arrhythmias, as well as maintained cardiac conduction. Whether intravenous injection of αCT1 or αCT11 produces similar outcomes has not been investigated. Given the possibility of peptide degradation in plasma, this study utilized in vivo I/R cardiac injury and ex vivo blood plasma models to examine factors that may limit the therapeutic potential of peptide therapeutics in vivo. Following tail vein administration of αCT11 (100 μM) in blood, no effect on I/R infarct size was observed in adult rat hearts on day 1 (D1) and day 28 (D28) after injury (p > 0.05). There was also no difference in the echocardiographic ejection fraction (EF%) between the control and the αCT11 groups (p > 0.05). Surprisingly, αCT11 in blood plasma collected from these rats was undetectable within ∼10 min after tail vein injection. To investigate factors that may modulate αCT11 degradation in blood, αCT11 was directly added to blood plasma isolated from normal rats without I/R and peptide levels were measured under different experimental conditions. Consistent with in vivo observations, significant αCT11 degradation occurred in plasma within 10 min at 22 and 37 °C and was nearly undetectable by 30 min. These responses were reduced by the addition of protease/phosphatase (PTase/PPTase) inhibitors to the isolated plasma. Interestingly, no significant differences in αCT11 degradation in plasma were noted between male and female rats. We conclude that fast degradation of αCT11 is likely the reason that no beneficial effects were observed in the in vivo I/R model and inhibition or shielding from PTase/PPTase activity may be a strategy that will assist with the viability of peptide therapeutics.
Acute adenoviral infection elicits an arrhythmogenic substrate prior to myocarditis
Padget, Rachel L.; Zeitz, Michael J.; Blair, Grace A.; Wu, Xiaobo; North, Michael D.; Tanenbaum, Mira T.; Stanley, Kari E.; Phillips, Chelsea M.; King, D. Ryan; Lamouille, Samy; Gourdie, Robert G.; Hoeker, Gregory S.; Swanger, Sharon A.; Poelzing, Steven; Smyth, James W. (American Heart Association, 2024-03-29)
BACKGROUND: Viral cardiac infection represents a significant clinical challenge encompassing several etiological agents, disease stages, complex presentation, and a resulting lack of mechanistic understanding. Myocarditis is a major cause of sudden cardiac death in young adults, where current knowledge in the field is dominated by later disease phases and pathological immune responses. However, little is known regarding how infection can acutely induce an arrhythmogenic substrate before significant immune responses. Adenovirus is a leading cause of myocarditis, but due to species specificity, models of infection are lacking, and it is not understood how adenoviral infection may underlie sudden cardiac arrest. Mouse adenovirus type-3 was previously reported as cardiotropic, yet it has not been utilized to understand the mechanisms of cardiac infection and pathology. METHODS: We have developed mouse adenovirus type-3 infection as a model to investigate acute cardiac infection and molecular alterations to the infected heart before an appreciable immune response or gross cardiomyopathy. RESULTS: Optical mapping of infected hearts exposes decreases in conduction velocity concomitant with increased Cx43^Ser368 phosphorylation, a residue known to regulate gap junction function. Hearts from animals harboring a phospho-null mutation at Cx43^Ser368 are protected against mouse adenovirus type-3–induced conduction velocity slowing. Additional to gap junction alterations, patch clamping of mouse adenovirus type-3–infected adult mouse ventricular cardiomyocytes reveals prolonged action potential duration as a result of decreased IK1 and IKs current density. Turning to human systems, we find human adenovirus type-5 increases phosphorylation of Cx43^Ser368 and disrupts synchrony in human induced pluripotent stem cell-derived cardiomyocytes, indicating common mechanisms with our mouse whole heart and adult cardiomyocyte data. CONCLUSIONS: Together, these findings demonstrate that adenoviral infection creates an arrhythmogenic substrate through direct targeting of gap junction and ion channel function in the heart. Such alterations are known to precipitate arrhythmias and likely contribute to sudden cardiac death in acutely infected patients.
Tumor-derived extracellular vesicles disrupt the blood-brain barrier endothelium following high-frequency irreversible electroporation
Murphy, Kelsey R.; Aycock, Kenneth N.; Marsh, Spencer; Hay, Alayna N.; Athanasiadi, Ilektra; Bracha, Shay; Chang, Christine; Gourdie, Robert G.; Davalos, Rafael V.; Rossmeisl, John H. Jr.; Dervisis, Nikolaos G. (Nature Portfolio, 2024-11-18)
High-frequency irreversible electroporation (H-FIRE), a nonthermal brain tumor ablation therapeutic, generates a central tumor ablation zone while transiently disrupting the peritumoral blood–brain barrier (BBB). We hypothesized that bystander effects of H-FIRE tumor cell ablation, mediated by small tumor-derived extracellular vesicles (sTDEV), disrupt the BBB endothelium. Monolayers of bEnd.3 cerebral endothelial cells were exposed to supernatants of H-FIRE or radiation (RT)-treated LL/2 and F98 cancer cells. Endothelial cell response was evaluated microscopically and via flow cytometry for apoptosis. sTDEV were isolated following H-FIRE and RT, characterized via nanoparticle tracking analysis (NTA) and transmission electron microscopy, and applied to a Transwell BBB endothelium model to quantify permeability changes. Supernatants of H-FIRE-treated tumor cells, but not supernatants of sham- or RT-treated cells, disrupted endothelial cell monolayer integrity while maintaining viability. sTDEV released by glioma cells treated with 3000 V/cm H-FIRE increased permeability of the BBB endothelium model compared to sTDEV released after lower H-FIRE doses and RT. NTA revealed significantly decreased sTDEV release after the 3000 V/cm H-FIRE dose. Our results demonstrate that sTDEV increase permeability of the BBB endothelium after H-FIRE ablation in vitro. sTDEV-mediated mechanisms of BBB disruption may be exploited for drug delivery to infiltrative margins following H-FIRE ablation.
Establishing Human and Canine Xenograft Murine Osteosarcoma Models for Application of Focused Ultrasound Ablation
Hay, Alayna N.; Simon, Alex; Ruger, Lauren N.; Gannon, Jessica; Coutermarsh-Ott, Sheryl; Vickers, Elliana R.; Eward, William; Neufeld, Nathan J.; Vlaisavljevich, Eli; Tuohy, Joanne (MDPI, 2025-08-30)
Background: Osteosarcoma (OS) is the most commonly occurring type of bone cancer in both humans and canines. The survival outcomes for OS patients have not improved significantly in decades. A novel and innovative treatment option that is currently under investigation for OS in the veterinary field is the focused ultrasound ablation modality, histotripsy. Histotripsy is a non-thermal, non-invasive, non-ionizing ablation modality that destroys tissue through generation of acoustic cavitation. Objective: In the current study, we sought to investigate the utility of an orthotropic OS xenograft murine model for characterization of chronic ablative and clinical outcomes post-histotripsy ablation. Method: Given the high comparative relevance of canine to human OS, histotripsy was delivered to orthotopic OS tumors in both human and canine xenograft murine models. Results: Histotripsy improved limb function in tumor-bearing mice compared to untreated tumor bearing mice. The results of this study demonstrated the utility of the orthotopic OS xenograft murine model for histotripsy-based preclinical studies. Conclusions: The current study is the first published investigation for the use of an orthotopic xenograft murine model for the development of histotripsy ablation for OS. The developmental process of the model, technical limitations, and future directions are discussed.
Precision Adjuvant Strategies in Vaccine Development for Substance Use Disorders: Variability and Mechanistic Insights
Bian, Yuanzhi; Ci, Qiaoqiao; Luo, Xin M.; Zhang, Chenming (MDPI, 2025-09-20)
Substance use disorders (SUDs) remain a major global health challenge with limited treatment options and high relapse rates. Vaccines that induce drug-sequestering antibodies have shown promise, but their efficacy is hindered by the poor immunogenicity of small-molecule haptens. Adjuvants, substances that enhance immune responses, are critical for overcoming this limitation and improving vaccine efficacy. This review synthesizes over two decades of preclinical and clinical research to guide rational adjuvant design for SUD vaccines. Five major adjuvant classes are examined: aluminum-salt adjuvants, emulsion adjuvants, toll-like receptor (TLR) agonists, protein immunopotentiators, and cytokine modulators. Their physicochemical properties, innate immune activation profiles, and applications in nicotine, stimulant, and opioid vaccines are discussed. Comparative analyses reveal pronounced drug-specific and carrier-specific variability. Case studies illustrate the superior performance of a complementary TLR-agonist pair in a nicotine nanovaccine versus its limited effect in oxycodone vaccines. They also reveal the differential efficacy of an oil-in-water emulsion adjuvant across antigen types. Four principles emerge: (i) no adjuvant is universally optimal; (ii) drug pharmacology influences immune signaling; (iii) adjuvant-carrier compatibility is important; (iv) complementary adjuvant pairings often outperform single agents. These insights support a precision-vaccinology paradigm that tailors adjuvant strategies to each drug class and the delivery vehicle, advancing the development of next-generation SUD vaccines.
Double-Outlet Right Ventricular Malformation in a Two-Year-Old Aberdeen Angus Cow
White, Baker; Carvallo-Chaigneau, Francisco R.; Cecere, Thomas E.; Mckenzie, Harold; Menciotti, Giulio; Umaña Sedó, Sebastián G. (MDPI, 2025-08-30)
A 2-year-old Aberdeen Angus cow was presented with lethargy and decreased appetite at the VA-MD College of Veterinary Medicine Large Animal Teaching Hospital. Initial clinical examination revealed cyanosis, tachycardia, polycythemia, and a significant increase in lactate levels. The heifer experienced spontaneous death while hospitalized, prompting a postmortem examination. Gross evaluation demonstrated that the aorta arose entirely from the right ventricle, while the main pulmonary artery maintained its normal position, consistent with a diagnosis of double-outlet right ventricle. Additional cardiac abnormalities were identified, including an atrial septal defect, ventricular septal defect and marked right ventricular hypertrophy. These defects fall under the category of double-outlet right ventricle malformation. While congenital heart defects are a more recognized cause of cardiac failure and mortality in calves, they should remain a consideration in cases of sudden death, even in adult cattle.
Design and Evaluation Novel Gene-Specific, Cell-Permeable Antisense Peptide Nucleic Acids to Prevent Staphylococcus Aureus Biofilm Formation
Col, Nihan Akguc; Rao, Jayasimha; Rajagopalan, Govindarajan; Sriranganathan, Nammalwar (Gavin Publishers, 2024-12-27)
Staphylococcus aureus, a Gram-positive bacterium, is a leading cause of various biofilm-associated infections in humans and animals, posing significant economic and healthcare challenges. Biofilms exhibit heightened resistance to antimicrobial agents as well as to immune-mediated clearance, thus persisting for long periods of time. Hence, novel therapeutic approaches are needed to eradicate S. aureus biofilms. Peptide nucleic acids (PNAs), synthetic DNA analogs with a peptide backbone instead of sugar backbone, offer a promising approach. In this study, we designed, synthesized and tested the efficacy of several synthetic antisense PNAs coupled with cell-penetrating peptides (CPPs), targeting essential and biofilm related S. aureus genes to inhibit staphylococcal biofilm growth using standard microtiter plate and tygon catheter biofilm assays. P-PNAs targeting the genes for intercellular adhesion locus, ica, cell wall/membrane/envelope biogenesis, fmhb, accessory regulator, sarA, sensor histidine kinase, saeS, repressor of toxins, rot, response regulator, yycF and histidine kinase, yycG genes were tested. Two scrambled PNAs and CPP alone were used as controls. Only one P-PNA, targeting sarA, showed the strongest biofilm inhibitory activity (up to 40 %) at a concentration of 50 μM or higher. This novel P-PNA could be a useful adjunct for the treatment S. aureus biofilm infections.
Broad Host Range Peptide Nucleic Acids Prevent Gram-Negative Biofilms Implicated in Catheter-Associated Urinary Tract Infections
Karp, Hannah Q.; Nowak, Elizabeth S.; Kropp, Gillian A.; Col, Nihan A.; Schulz, Michael D.; Sriranganathan, Nammalwar; Rao, Jayasimha (MDPI, 2025-08-20)
Biofilms develop in sequential steps resulting in the formation of three-dimensional communities of microorganisms that are encased in self-produced extracellular polymeric substances. Biofilms play a key role in device-associated infections, such as catheter-associated urinary tract infections (CAUTIs), because they protect microorganisms from standard antimicrobial therapies. Current strategies to prevent biofilm formation in catheter-related infections, including prophylactic antibiotics and antibiotic-coated catheters, have been unsuccessful. This finding highlights a need for novel approaches to address this clinical problem. In this study, biofilm-forming phenotypes of common Gram-negative bacteria associated with CAUTIs were treated with antisense peptide nucleic acids (PNAs), and biofilm biomass and bacterial viability were quantified after 24 h of treatment. A cocktail of PNAs targeting the global regulator genes rsmA, amrZ, and rpoS in Pseudomonas aeruginosa significantly reduced viability and thus appropriately eliminated biofilm biomass. Antisense-PNAs against these same gene targets and the motility regulator gene motA inhibited biofilm formation among isolates of Klebsiella pneumoniae, Enterobacter cloacae, and Escherichia coli but did not reduce bacterial viability. These results suggest that antisense-PNAs are a promising new technology in preventing biofilm formation in urinary catheters, especially as a potential complement to conventional antimicrobials.
Elevated EGR1 binding at enhancers in excitatory neurons correlates with neuronal subtype-specific epigenetic regulation
Yin, Liduo; Xu, Xiguang; Conacher, Benjamin; Lin, Yu; Carrillo, Gabriela L.; Cun, Yupeng; Fox, Michael A.; Lu, Xuemei; Xie, Hehuang (2025-08-11)
Background: Brain development and neuronal cell specification are accompanied by epigenetic changes that enable the regulation of diverse gene expression patterns. During these processes, transcription factors interact with cell-type-specific epigenetic marks, binding to unique sets of cis-regulatory elements in different cell types. However, the detailed mechanisms through which cell-type-specific gene regulation is established in neurons remain to be explored. Results: In this study, we conducted a comparative histone modification analysis between excitatory and inhibitory neurons. Our results revealed that neuronal cell-type-specific histone modifications are enriched in super enhancer regions that contain abundant EGR1 motifs. Further CUT&RUN assay confirmed that excitatory neurons exhibit more EGR1 binding sites, primarily located in enhancers. Integrative analysis demonstrated that EGR1 binding is strongly correlated with various epigenetic markers of open chromatin regions and is linked to distinct gene pathways specific to neuronal subtypes. In inhibitory neurons, most genomic regions containing EGR1 binding sites become accessible during early embryonic stages, whereas super enhancers in excitatory neurons, which also host EGR1 binding sites, gain accessibility during postnatal stages. Conclusions: This study highlights the crucial role of transcription factor binding, such as EGR1, to enhancer regions, which may be key to establishing cell-type-specific gene regulation in neurons.
Insights from Mass Spectrometry-Based Proteomics on Cryptococcus neoformans
Betancourt, Jovany Jordan; Nielsen, Kirsten (MDPI, 2025-07-17)
Cryptococcus neoformans is an opportunistic fungal pathogen and causative agent of cryptococcosis and cryptococcal meningitis (CM). Cryptococcal disease accounts for up to 19% of AIDS-related mortalities globally, warranting its label as a pathogen of critical priority by the World Health Organization. Standard treatments for CM rely heavily on high doses of antifungal agents for long periods of time, contributing to the growing issue of antifungal resistance. Moreover, mortality rates for CM are still incredibly high (13–78%). Attempts to create new and effective treatments have been slow due to the complex and diverse set of immune-evasive and survival-enhancing virulence factors that C. neoformans employs. To bolster the development of better clinical tools, deeper study into host–Cryptococcus proteomes is needed to identify clinically relevant proteins, pathways, antigens, and beneficial host response mechanisms. Mass spectrometry-based proteomics approaches serve as invaluable tools for investigating these complex questions. Here, we discuss some of the insights into cryptococcal disease and biology learned using proteomics, including target proteins and pathways regulating Cryptococcus virulence factors, metabolism, and host defense responses. By utilizing proteomics to probe deeper into these protein interaction networks, new clinical tools for detecting, diagnosing, and treating C. neoformans can be developed.
Larval environment reshapes mosquito disease risk via phenotypic and molecular plasticity
Chandrasegaran, Karthikeyan; Walker, Melody; Marano, Jeffrey M.; Rami, Spruha; Bisese, Adaline; Weger-Lucarelli, James; Lahondère, Chloé; Robert, Michael A.; Childs, Lauren M.; Vinauger, Clément (2025-06-21)
Early-life environmental conditions can exert profound, lasting effects on adult phenotypes, with major consequences for fitness and disease transmission, especially in holometabolous insects like mosquitoes, which are a key vector species. Yet, the molecular mechanisms through which juvenile environments shape adult physiology and behavior via transstadial effects remain largely unresolved. Here, we demonstrate that larval competition, a key ecological stressor, profoundly alters adult body size, survival, reproductive output, host-seeking behavior, olfactory neurophysiology, and vector competence in the mosquito Aedes aegypti. Crucially, using transcriptomic profiling and integrative network analyses, we identify seven regulatory hub genes whose expression is strongly associated with size-dependent variation in olfactory behavior, reproductive investment, and Zika virus transmission potential. These hub genes belong to gene modules enriched for functions in chemosensory processing, metabolic regulation, and signal transduction, revealing a molecular framework mediating environmentally induced plasticity across metamorphosis. Integrating these empirical findings into a transmission model, we show that incomplete larval control can inadvertently increase outbreak risk by producing larger, longer-lived, and more competent vectors. Our results uncover molecular mechanisms underpinning phenotypic plasticity in disease vectors and highlight the critical need to account for transstadial effects in models of vector-borne disease transmission.
Development of a Selective Agar for the Detection of Probiotic Strain Ligilactobacillus animalis NP51 and Other Lactic Acid Bacteria in Cattle Feed
Thompson, Kasey; Akter, Shamima; Ferguson-Noel, Naola; Maurer, John J.; Lee, Margie D. (MDPI, 2025-06-13)
The enormous potential of bacteriotherapy in disease treatment and prevention has created a large probiotic market. Significant challenges exist in assessing probiotic quality, efficacy and viability. Lactic acid bacteria (LAB) are commonly used probiotics and the most abundant of the vertebrate microbiota. The goal of this study was to make MRS agar specific for probiotic Ligilactobacillus animalis NP51, since the current formulation is not sufficiently selective. Here, 53 chemicals were screened to identify compound(s) that reduced the growth of non-LAB and fungi on de Mann, Rogosa, and Sharpe (MRS) agar, and which were selective for LAB and specifically the probiotic strain NP51. Cattle feed was selected as the sample type, as it is commonly amended with Lactobacillus or yeast probiotics and often includes silage, a diverse microbial consortium of fungi and LAB. Modified MRS was evaluated for its effectiveness in determining probiotic viability and the detection of L. animalis NP51 in cattle feed, amended with this probiotic. qPCR was used to specifically detect and enumerate NP51 in commercial and experimental feed samples. For four selective agents, nystatin, guanidine hydrochloride, CuSO₄, and ZnCl, it was identified that when used together, they reduced the growth of bacteria and fungi, but did not inhibit the Lactobacillus probiotic NP51 and other LAB. Metagenomic analysis revealed LAB as the major group cultivated on modified MRS agar from the plating of cattle feed amended with silage. As an enrichment, modified MRS broth improved the qPCR detection of probiotic strain NP51. This study illustrated that improvements can be made to existing bacteriological media for enumerating probiotic NP51 and determining the product’s viability.

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