Protein kinase C-⑀ (PKC-⑀) translocates to phagosomes and promotes uptake of IgG-opsonized targets. To identify the regions responsible for this concentration, green fluorescent protein (GFP)-protein kinase C-⑀ mutants were tracked during phagocytosis and in response to exogenous lipids. Deletion of the diacylglycerol (DAG)-binding ⑀C1 and ⑀C1B domains, or the ⑀C1B point mutant ⑀C259G, decreased accumulation at phagosomes and membrane translocation in response to exogenous DAG. Quantitation of GFP revealed that ⑀C259G, ⑀C1, and ⑀C1B accumulation at phagosomes was significantly less than that of intact PKC-⑀. Also, the DAG antagonist 1-hexadecyl-2-acetyl glycerol (EI-150) blocked PKC-⑀ translocation. Thus, DAG binding to ⑀C1B is necessary for PKC-⑀ translocation. The role of phospholipase D (PLD), phosphatidylinositol-specific phospholipase C (PI-PLC)-␥1, and PI-PLC-␥2 in PKC-⑀ accumulation was assessed. Although GFP-PLD2 localized to phagosomes and enhanced phagocytosis, PLD inhibition did not alter target ingestion or PKC-⑀ localization. In contrast, the PI-PLC inhibitor U73122 decreased both phagocytosis and PKC-⑀ accumulation. Although expression of PI-PLC-␥2 is higher than that of PI-PLC-␥1, PI-PLC-␥1 but not PI-PLC-␥2 consistently concentrated at phagosomes. Macrophages from PI-PLC-␥2؊/؊ mice were similar to wild-type macrophages in their rate and extent of phagocytosis, their accumulation of PKC-⑀ at the phagosome, and their sensitivity to U73122. This implicates PI-PLC-␥1 as the enzyme that supports PKC-⑀ localization and phagocytosis. That PI-PLC-␥1 was transiently tyrosine phosphorylated in nascent phagosomes is consistent with this conclusion. Together, these results support a model in which PI-PLC-␥1 provides DAG that binds to ⑀C1B, facilitating PKC-⑀ localization to phagosomes for efficient IgGmediated phagocytosis.

Certain microbes invade brain microvascular endothelial cells (BMECs) to breach the blood-brain barrier (BBB) and establish central nervous system (CNS) infection. Here we use the leading meningitis pathogen group B Streptococcus (GBS) together with insect and mammalian infection models to probe a potential role of glycosaminoglycan (GAG) interactions in the pathogenesis of CNS entry. Site-directed mutagenesis of a GAG-binding domain of the surface GBS alpha C protein impeded GBS penetration of the Drosophila BBB in vivo and diminished GBS adherence to and invasion of human BMECs in vitro. Conversely, genetic impairment of GAG expression in flies or mice reduced GBS dissemination into the brain. These complementary approaches identify a role for bacterial-GAG interactions in the pathogenesis of CNS infection. Our results also highlight how the simpler yet genetically conserved Drosophila GAG pathways can provide a model organism to screen candidate molecules that can interrupt pathogen-GAG interactions for future therapeutic applications.

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The coronavirus (COVID-19) has greatly impacted healthcare systems worldwide, leading to an unprecedented rise in demand for healthcare resources. In anticipation of an acute strain on established medical facilities in Dallas, Texas, federal officials worked in conjunction with local medical personnel to convert a convention center into a Federal Medical Station capable of caring for patients affected by COVID-19. A 200,000 square foot event space was designated as a direct patient care area, with surrounding spaces repurposed to house ancillary services. Given the highly transmissible nature of the novel coronavirus, the donning and doffing of personal protective equipment (PPE) was of particular importance for personnel staffing the facility. Furthermore, nationwide shortages in the availability of PPE necessitated the reuse of certain protective materials. This article seeks to delineate the procedures implemented regarding PPE in the setting of a COVID-19 disaster response shelter, including workspace flow, donning and doffing procedures, PPE conservation, and exposure event protocols.