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<jats:p>Although Huntington’s disease is a late-manifesting neurodegenerative disorder, both mouse studies and neuroimaging studies of presymptomatic mutation carriers suggest that Huntington’s disease might affect neurodevelopment. To determine whether this is actually the case, we examined tissue from human fetuses (13 weeks gestation) that carried the Huntington’s disease mutation. These tissues showed clear abnormalities in the developing cortex, including mislocalization of mutant huntingtin and junctional complex proteins, defects in neuroprogenitor cell polarity and differentiation, abnormal ciliogenesis, and changes in mitosis and cell cycle progression. We observed the same phenomena in Huntington’s disease mouse embryos, where we linked these abnormalities to defects in interkinetic nuclear migration of progenitor cells. Huntington’s disease thus has a neurodevelopmental component and is not solely a degenerative disease.</jats:p>

<jats:p>Monoclonal antibodies (mAbs) targeting human antigen CD20 (cluster of differentiation 20) constitute important immunotherapies for the treatment of B cell malignancies and autoimmune diseases. Type I and II therapeutic mAbs differ in B cell binding properties and cytotoxic effects, reflecting differential interaction mechanisms with CD20. Here we present 3.7- to 4.7-angstrom cryo–electron microscopy structures of full-length CD20 in complexes with prototypical type I rituximab and ofatumumab and type II obinutuzumab. The structures and binding thermodynamics demonstrate that upon binding to CD20, type II mAbs form terminal complexes that preclude recruitment of additional mAbs and complement components, whereas type I complexes act as molecular seeds to increase mAb local concentration for efficient complement activation. Among type I mAbs, ofatumumab complexes display optimal geometry for complement recruitment. The uncovered mechanisms should aid rational design of next-generation immunotherapies targeting CD20.</jats:p>

<jats:p>Polycyclic diterpenes exhibit many important biological activities, but de novo synthetic access to these molecules is highly challenging because of their structural complexity. Semisynthetic access has also been limited by the lack of chemical tools for scaffold modifications. We report a chemoenzymatic platform to access highly oxidized diterpenes by a hybrid oxidative approach that strategically combines chemical and enzymatic oxidation methods. This approach allows for selective oxidations of previously inaccessible sites on the parent carbocycles and enables abiotic skeletal rearrangements to additional underlying architectures. We synthesized a total of nine complex natural products with rich oxygenation patterns and skeletal diversity in 10 steps or less from <jats:italic>ent</jats:italic>-steviol.</jats:p>

<jats:p>The global coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made the development of a vaccine a top biomedical priority. In this study, we developed a series of DNA vaccine candidates expressing different forms of the SARS-CoV-2 spike (S) protein and evaluated them in 35 rhesus macaques. Vaccinated animals developed humoral and cellular immune responses, including neutralizing antibody titers at levels comparable to those found in convalescent humans and macaques infected with SARS-CoV-2. After vaccination, all animals were challenged with SARS-CoV-2, and the vaccine encoding the full-length S protein resulted in &gt;3.1 and &gt;3.7 log<jats:sub>10</jats:sub> reductions in median viral loads in bronchoalveolar lavage and nasal mucosa, respectively, as compared with viral loads in sham controls. Vaccine-elicited neutralizing antibody titers correlated with protective efficacy, suggesting an immune correlate of protection. These data demonstrate vaccine protection against SARS-CoV-2 in nonhuman primates.</jats:p>