Biology subjects

Wise, E.

Publications and source records attributed to Wise, E..

4 recordsLinked to original sources

bioRxiv2024

Interstitial infusion of purified collagenase Clostridium histolyticum in the cirrhotic liver causes rapid reduction in fibrosis with minimal liver toxicity

Crude mixtures of matrix-degrading enzymes called collagenase Clostridium histolyticum (CCH) have been used to efficiently breakdown tissue for many years. Recently, direct injection of purified CCH has been successfully developed as a treatment for Dupuytrens contracture (DC), a fibrotic disorder of the hand. Given similar histologic and mechanical features between the fibrous bands in DC and cirrhosis, a similar approach may be feasible for the treatment of cirrhosis. Crude and purified CCH were first compared through composition and substrate specificity. The biodistribution of a macromolecule delivered via interstitial infusion in the liver was mapped and quantified with a fluorescent dextran tracer to design a protocol for efficient delivery throughout the liver with minimal off-target exposure. Safety and efficacy of interstitial CCH infusion in the liver was investigated in cirrhotic mice using serum markers of injury and histological analysis of fibrosis. Purified CCH showed high purity and efficient degradation of type I collagen. Tracer experiments showed that interstitial infusion in one lobe of the liver will reach the entire organ in the mouse. A significant amount of the tracer was also found to enter the bloodstream where it is cleared by the kidneys, but was not found to significantly infiltrate other organs. Mild elevation in liver enzymes AST and ALT were observed 1d after infusion of purified CCH, but this was not significantly different than infusion with saline. No elevation in creatinine was observed. Cirrhotic mice infused with purified CCH showed 38% reduction in collagen proportionate area compared to mice infused with saline. These results show interstitial delivery of purified CCH in the cirrhotic liver rapidly decreases collagen content with minimal liver toxicity. This strategy merits further study as a potential treatment for cirrhosis.

bioengineering↗

bioRxiv2022

Dysregulated nuclear export of the late herpes simplex virus 1 transcriptome through the vhs-VP22 axis uncouples virus cytopathic effect and virus production

Herpes simplex virus 1 (HSV1) expresses its genes in a classical cascade culminating in the production of large amounts of structural proteins to facilitate virus assembly. HSV1 lacking the virus protein VP22 ({Delta}22) exhibits late translational shutoff, a phenotype that has been attributed to the unrestrained activity of the virion host shutoff (vhs) protein, a virus-encoded endoribonuclease which induces mRNA degradation during infection. We have previously shown that vhs is also involved in regulating the nuclear-cytoplasmic compartmentalisation of the virus transcriptome, and in the absence of VP22 many virus transcripts are sequestered in the nucleus late in infection. Here we show that despite expressing minimal amounts of structural proteins and failing to plaque on human fibroblasts, the strain 17 {Delta}22 virus replicates and spreads as efficiently as Wt virus, but without causing cytopathic effect (CPE). Nonetheless, CPE-causing virus spontaneously appeared on {Delta}22-infected human fibroblasts, and four viruses isolated in this way had all acquired point mutations in vhs which rescued viral mRNA export and late protein translation. However, unlike a virus deleted for vhs, these viruses still induced the degradation of cellular mRNA, suggesting that vhs mutation in the absence of VP22 is necessary to overcome a disturbance in mRNA export rather than mRNA degradation. The ultimate outcome of secondary mutations in vhs is therefore the rescue of virus-induced CPE caused by late protein synthesis, and while there is a clear selective pressure on HSV1 to mutate vhs for optimal production of late structural proteins, the purpose of this is over and above that of virus production. Author SummaryHSV is a human pathogen that lytically infects cells of the epidermis. Following viral genome replication, structural proteins are produced in abundance to enable the rapid assembly and release of large quantities of infectious progeny. Infected cells also exhibit cytopathic effect (CPE), morphological changes that are exemplified by cell rounding and the breakage of cell-to-cell contacts, facilitating virus dissemination. Here we show that HSV1 with a mutation that results in the nuclear retention of viral mRNA and concomitant shutdown of late protein synthesis, also fails to cause CPE. However, unexpectedly, we found that this virus is still able to release large numbers of infectious virus which can spread between cells without any evidence of cell damage. Nonetheless, despite efficient virus productivity, this virus spontaneously mutates to rescue late protein production and CPE, with mutations mapping to the process of mRNA export. There is therefore a clear selective pressure on HSV1 to optimize the synthesis of late structural proteins, but the purpose of this is over and above that of virus production, a result that has implications for why viruses in general express such large amounts of structural proteins.

microbiology↗

bioRxiv2019

The evolutionary dynamics of Oropouche Virus (OROV) in South America

The Amazon basin is host to numerous arthropod-borne viral pathogens that cause febrile disease in humans. Among these, Oropouche orthobunyavirus (OROV) is a relatively understudied member of the Peribunyavirales that causes periodic outbreaks in human populations in Brazil and other South American countries. Although several studies have described the genetic diversity of the virus, the evolutionary processes that shape the viral genome remain poorly understood. Here we present a comprehensive study of the genomic dynamics of OROV that encompasses phylogenetic analysis, evolutionary rate estimates, inference of natural selective pressures, recombination and reassortment, and structural analysis of OROV variants. Our study includes all available published sequences, as well as a set of new OROV genomes sequences obtained from patients in Ecuador, representing the first set of viral genomes from this country. Our results show that differing evolutionary processes on the three segments that encompass the viral genome lead to variable evolutionary rates and TMRCAs that could be explained by cryptic reassortment. We also present the discovery of previously unobserved putative N-linked glycosylation sites, and codons which evolve under positive selection on the viral surface proteins, and discuss the potential role of these features in the evolution of the virus through a combined phylogenetic and structural approach.

evolutionary biology↗

bioRxiv2018

Probabilistic modeling of personalized drug combinations from integrated chemical screen and molecular data in sarcoma

Cancer patients with advanced disease exhaust available clinical regimens and lack actionable genomic medicine results, leaving a large patient population without effective treatments options when their disease inevitably progresses. To address the unmet clinical need for evidence-based therapy assignment when standard clinical approaches have failed, we have developed a probabilistic computational modeling approach which integrates sequencing data with functional assay data to develop patient-specific combination cancer treatments. This computational modeling approach addresses three major challenges in personalized cancer therapy, which we validate across multiple species via computationally-designed personalized synergistic drug combination predictions, identification of unifying therapeutic targets to overcome intra-tumor heterogeneity, and mitigation of cancer cell resistance and rewiring mechanisms. These proof-of-concept studies support the use of an integrative functional approach to personalized combination therapy prediction for the population of high-risk cancer patients lacking viable clinical options and without actionable DNA sequencing-based therapy.

bioinformatics↗