University of Maryland Eastern Shore

Dorsal root ganglion (DRG) neurons play a pivotal role in transmitting sensory information from the periphery to the central nervous system, mediating diverse stimuli such as pain, touch, and temperature. Despite advances, translating findings from rodent models to human applications remains challenging due to species-specific differences, necessitating reliable human DRG neuron models. The immortalized human DRG neuronal cell line HD10.6, derived from embryonic DRG cells and capable of differentiating into functional nociceptive-like neurons, offers a promising in vitro system for studying sensory neuron biology and drug screening. This study explores the utility of GCaMP6s, a genetically encoded calcium indicator, as a molecular tool for imaging sensory activation in HD10.6 cells. To establish HD10.6 as a robust human DRG model, we constructed and characterized adeno-associated virus (AAV9) vectors for efficient GCaMP6s delivery. Differentiated HD10.6 cells were efficiently transduced, and calcium dynamics were validated to assess functional responses to sensory stimuli. The results showed that AAV9 serotype was sufficient to infect HD10.6 and the GCaMP6s was successfully introduced into the cells. The HD10.6-GCaMP6s responded to capsaicin well under the appropriate condition. A series of viral infection studies indicated that herpesvirus HSV-1 triggered robust calcium influx within 5 min after the exposure to the virus. Our findings highlight the potential of GCaMP6s-expressing HD10.6 cells as a high-throughput platform for studying nociception, neuronal signaling, host cell responses to viruses, and therapeutic interventions, bridging the gap between preclinical research and clinical applications.

The life-threatening coronavirus disease 2019 (COVID-19) affects about 1 in 1,000 healthy people under 50 without underlying conditions. Among patients with critical COVID-19 pneumonia, rare germline variants at genes controlling type I IFN immunity have been reported in up to 5% of patients. Causal etiologies in 80-85% of cases are still unknown. We analyzed two families with hypoxemic COVID-19 pneumonia for known single-gene inborn errors of immunity. In Family 1, two siblings with critical COVID-19 were homozygous for a DOCK2 variant, c.3624+5G>A. DOCK2 deficiency is a known T-cell disorder underlying severe viral diseases. The variant resulted in skipping exon 35, which was predicted to produce a frameshift truncated protein (p.L1157Ifs*12). The proband showed markedly decreased blood CD4 T-helper cell counts, impaired T lymphocyte transformation test, and increased serum IgG, IgA, and IgE levels, as documented in other DOCK2-deficient patients. In Family 2, the proband had lethal COVID-19 and HPV-2-associated multiple recalcitrant warts. She was heterozygous for a deletion in GATA2:c.1075_1102del28, p.W360Sfs*18. GATA2 haploinsufficiency is a known cause of severe viral diseases due to a lack of plasmacytoid dendritic cell (pDC) development. The proband had monocytopenia and a lack of circulating pDCs, as reported in other patients with GATA2 haploinsufficiency. Overall, both DOCK2 deficiency and GATA2 haploinsufficiency are associated with critical and often fatal COVID-19 pneumonia.

Since the 15th century, scientists have been working to address biofouling, the accumulation of biofilm on submerged surfaces, like ships and buoys. Key stages in this process include bacterial precipitation and radical polymerization of bacteria's metabolites. Along with corrosion and extended fuel consumption by ships, biofilm also contributes to ecological changes by spreading invasive bacterial species across the world when segments of biofilm are detached from moving ships. Historically, effective antifouling solutions have been toxic to marine ecosystems and are now banned in many regions, including the US. While recently developed highly hydrophobic polymers have promise, they are currently expensive and challenging for technology transfer.As an alternative solution, nontoxic formulations have been studied for antifouling coatings that utilize organic renewable superfruits, medicinal herbs, and nonbiofilm-forming algae rich in antioxidants and/or essential oils and terpenes, combined with biocompatible polymers. It is hypothesized that antibacterial essential oils and terpenes would prevent precipitation and growth of bacteria on the protected surfaces, while antioxidants, which are natural free radical scavengers, would significantly slow down polymerization processes in the biofilms. This study focuses on formulations created with extracts of A. mitshurinii, known for its high antioxidant concentrations. Current short-term results indicate that A. mitschurnii serves as an effective antifouling agent in both freshwater and saltwater, but with a higher performance in freshwater environments. The influence of bacteria and phytochemical concentrations will be discussed, along with the current antifouling methodology and postsurface analysis.