Neuronal expression of herpes simplex virus-1 VP16 protein induces pseudorabies virus escape from silencing and reactivation.

Alpha herpesvirus (α-HV) particles enter their hosts from mucosal surfaces and efficiently maintain fast transport in peripheral nervous system (PNS) axons to establish infections in the peripheral ganglia. The path from axons to distant neuronal nuclei is challenging to dissect due to the difficulty of monitoring early events in a dispersed neuron culture model. We have established well-controlled, reproducible, and reactivateable latent infections in compartmented rodent neurons by infecting physically isolated axons with a small number of viral particles. This system not only recapitulates the physiological infection route but also facilitates independent treatment of isolated cell bodies or axons. Consequently, this system enables study not only of the stimuli that promote reactivation but also the factors that regulate the initial switch from productive to latent infection. Adeno-associated virus (AAV)-mediated expression of herpes simplex-1 (HSV-1) VP16 alone in neuronal cell bodies enabled the escape from silencing of incoming pseudorabies virus (PRV) genomes. Furthermore, the expression of HSV VP16 alone reactivated a latent PRV infection in this system. Surprisingly, the expression of PRV VP16 protein supported neither PRV escape from silencing nor reactivation. We compared transcription transactivation activity of both VP16 proteins in primary neurons by RNA sequencing and found that these homolog viral proteins produce different gene expression profiles. AAV-transduced HSV VP16 specifically induced the expression of proto-oncogenes including c-Jun and Pim2. In addition, HSV VP16 induces phosphorylation of c-Jun in neurons, and when this activity is inhibited, escape of PRV silencing is dramatically reduced.IMPORTANCEDuring latency, alpha herpesvirus genomes are silenced yet retain the capacity to reactivate. Currently, host and viral protein interactions that determine the establishment of latency, induce escape from genome silencing or reactivation are not completely understood. By using a compartmented neuronal culture model of latency, we investigated the effect of the viral transcriptional activator, VP16 on pseudorabies virus (PRV) escape from genome silencing. This model recapitulates the physiological infection route and enables the study of the stimuli that regulate the initial switch from a latent to productive infection. We investigated the neuronal transcriptional activation profiles of two homolog VP16 proteins (encoded by HSV-1 or PRV) and found distinct gene activation signatures leading to diverse infection outcomes. This study contributes to understanding of how alpha herpesvirus proteins modulate neuronal gene expression leading to the initiation of a productive or a latent infection.

An analysis of patterns of distribution of buprenorphine in the United States using ARCOS, Medicaid, and Medicare databases.

Opioid overdose remains a problem in the United States despite pharmacotherapies, such as buprenorphine, in the treatment of opioid use disorder. This study characterized changes in buprenorphine use. Using the Drug Enforcement Administration's ARCOS, Medicaid, and Medicare claims databases, patterns in buprenorphine usage in the United States from 2018 to 2020 were analyzed by examining percentage changes in total grams distributed and changes in grams per 100 K people in year-to-year usage based on ZIP code and state levels. For ARCOS from 2018 to 2019 and 2019 to 2020, total buprenorphine distribution in grams increased by 16.2% and 12.6%, respectively. South Dakota showed the largest statewide percentage increase in both 2018-2019 (66.1%) and 2019-2020 (36.7%). From 2018 to 2019, the ZIP codes ND-577 (156.4%) and VA-222 (-82.1%) had the largest and smallest percentage changes, respectively. From 2019 to 2020, CA-932 (250.2%) and IL-603 (-36.8%) were the largest and smallest, respectively. In both 2018-2019 and 2019-2020, PA-191 had the second highest increase in grams per 100K while OH-452 was the only ZIP code to remain in the top three largest decreases in grams per 100K in both periods. Among Medicaid patients in 2018, there was a nearly 2000-fold difference in prescriptions per 100k Medicaid enrollees between Kentucky (12 075) and Nebraska (6). Among Medicare enrollees in 2018, family medicine physicians and other primary care providers were the top buprenorphine prescribers. This study not only identified overall increases in buprenorphine availability but also pronounced state-level differences. Such geographic analysis can be used to discern which public policies and regional factors impact buprenorphine access.