Highlights d Defective viral genomes predominate in treated SIV mac and HIV-2 infection d Significantly more SIV proviruses are intact compared to HIV-1 in treated humans d Compared to HIV, clonal sequences and deleted genomes are less frequent in SIV infection d An assay to directly enumerate intact SIV genomes was developed

HIV-1 sequence diversity presents a major challenge for the clinical development of broadly neutralizing antibodies (bNAbs) for both therapy and prevention. Sequence variation in critical bNAb epitopes has been observed in the majority of HIV-1 infected individuals and can lead to viral escape following bNAb monotherapy in humans. In this study, we show that viral sequence diversity can limit both the therapeutic and prophylactic efficacy of bNAbs in rhesus monkeys. We first demonstrate that monotherapy with the V3 glycan-dependent antibody 10-1074, but not PGT121, results in rapid selection of pre-existing viral variants containing N332/S334 escape mutations and loss of therapeutic efficacy in SHIV-SF162P3-infected rhesus monkeys. We then show that the V3 glycan-dependent antibody PGT121 alone and the V2 glycan-dependent antibody PGDM1400 alone both fail to protect against a mixed challenge with SHIV-SF162P3 and SHIV-325C. In contrast, the combination of both bNAbs provides 100% protection against this mixed SHIV challenge. These data reveal that single bNAbs efficiently select resistant viruses from a diverse challenge swarm to establish infection, demonstrating the importance of bNAb cocktails for HIV-1 prevention.

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The cellular endosomal sorting complex required for transport (ESCRT) was recently found to mediate important morphogenesis processes at the nuclear envelope (NE). We previously showed that the Epstein-Barr virus (EBV) BFRF1 protein recruits the ESCRT-associated protein Alix to modulate NE structure and promote EBV nuclear egress. Here, we uncover new cellular factors and mechanisms involved in this process. BFRF1-induced NE vesicles are similar to those observed following EBV reactivation. BFRF1 is ubiquitinated, and elimination of possible ubiquitination by either lysine mutations or fusion of a deubiquitinase hampers NE-derived vesicle formation and virus maturation. While it interacts with multiple Nedd4-like ubiquitin ligases, BFRF1 preferentially binds Itch ligase. We show that Itch associates with Alix and BFRF1 and is required for BFRF1-induced NE vesicle formation. Our data demonstrate that Itch, ubiquitin, and Alix control the BFRF1-mediated modulation of the NE and EBV maturation, uncovering novel regulatory mechanisms of nuclear egress of viral nucleocapsids. IMPORTANCEThe nuclear envelope (NE) of eukaryotic cells not only serves as a transverse scaffold for cellular processes, but also as a natural barrier for most DNA viruses that assemble their nucleocapsids in the nucleus. Previously, we showed that the cellular endosomal sorting complex required for transport (ESCRT) machinery is required for the nuclear egress of EBV. Here, we further report the molecular interplay among viral BFRF1, the ESCRT adaptor Alix, and the ubiquitin ligase Itch. We found that BFRF1-induced NE vesicles are similar to those observed following EBV reactivation. The lysine residues and the ubiquitination of BFRF1 regulate the formation of BFRF1-induced NE-derived vesicles and EBV maturation. During the process, a ubiquitin ligase, Itch, preferably associates with BFRF1 and is required for BFRF1-induced NE vesicle formation. Therefore, our data indicate that Itch, ubiquitin, and Alix control the BFRF1-mediated modulation of the NE, suggesting novel regulatory mechanisms for ESCRT-mediated NE modulation. T he eukaryotic nuclear envelope (NE) is a specialized compartment composed of double lipid-bilayer membranes and an underlying proteinaceous lamina network and connected by membrane-integrating nuclear pore complexes (NPCs) that selectively regulate the nucleocytoplasmic transport of macromolecules. The NE not only provides an intact meshwork to protect the genome's integrity from cytoplasmic insults, but also serves as a natural barrier against most DNA viruses that replicate their genomes within the nucleus (1). DNA viruses thus evolve various strategies to modify the NE for efficient material transport and nuclear egress of viral nucleocapsids.Epstein-Barr virus (EBV) is a gammaherpesvirus that infects most of the human population. After primary infection, EBV becomes latent in resting B cells and can be reactivated periodically for lytic replication and virus shedding. During lytic infection, several EBV gene pr...

This review briefly summarizes the situation regarding food security in East and Southeast Asia. In accordance with the World Food Summit definition and 2009 Declaration of the World Summit on Food Security, the four pillars of food security—food availability, access to food, the stability of food supplies, and food utilization—are closely scrutinized along with the characteristics of food security at the sub-regional level. Historical trends for the agricultural economy and the food trade, such as food imports and exports, production and consumption, and the food price index in the sub-region, are presented and statistically analysed. Additionally, because agricultural industry in this region is vulnerable to climate change, issues about how climate change affects food security in food production systems, agricultural livelihoods, nutrition, and food policy making, which can be linked to the four pillars in different ways, are also discussed.