The rockefeller university

Dengue virus (DENV) is a mosquito-transmitted flavivirus; there are four serotypes (DENV1-4) that co-circulate globally. Primary infection causes self-limiting febrile illness, but secondary infection by a heterologous serotype can predispose to severe dengue. Neutralizing antibodies are key mediators of long-term protection; however, cross-reactive, non-neutralizing antibodies can cause antibody-dependent enhancement (ADE) of infection, which contributes to severe dengue. Therefore, elicitation of a potent, broadly neutralizing antibody response against all four DENV serotypes is desired for vaccine design. Here, we developed nano-particle immunogens bearing engineered variants of the E glycoprotein DIII domain (DIII) in which epitopes targeted by non-neutralizing antibodies were mutated via structure-guided design and phage display. A two-component cocktail of these DIII variants elicited a broadly neutralizing response against all four DENV serotypes in mice and limited viremia in a DENV2 challenge model. These results provide insights into the design of broadly acting vaccines against DENV serotypes.

Ervin Bauer (1890-1938) outlined the paradigm of theoretical biology in his monograph "Fundamental Principles of Biology as Pure Natural Science and their Applications in Physiology and Pathology" (1920) and further developed these ideas in his book "Theoretical Biology" (1935). In these works, he defined the foundations of theoretical biology from the perspective of biophysics and bioenergetics, formulated the principle of a sustainable non-equilibrium state, which is continuously maintained by all biological systems throughout their life, and developed original views on cell differentiation, adaptation, and evolution. In 1938, Ervin Bauer and his wife Stefania became the victims of Stalin's Great Terror. The book of 1920 was published in German. It outlines the main principles of Bauer's concept. Bauer's magnum opus "Theoretical Biology" (1935) was published in Russian and republished in 1967 in Hungarian (together with the monograph of 1920) and several times in Russian. Immediately after the Russian edition appeared, two chapters were also published in German translation. Only small excerpts of the book were published in English translation. Here we present a complete English translation of both books. The books contain many important ideas that remain actual today and have great potential for further development in modern concepts of the foundations of life, the structure of living matter, and evolution.

CD4+ T cells are indispensable for optimal immunity to Mycobacterium tuberculosis (M.tb), a pathogen that triggers tuberculosis (TB) in humans. M.tb-specific human CD4+ T cells are known to polarize toward an interferon-gamma (IFN-gamma)-producing, CCR4-CCR6+CXCR3+T-bet+ROR gamma T+ T helper 1* cell (TH1*cell) memory phenotype. We report that autosomal recessive deficiency of the human lymphocytic surface receptor LY9 (SLAMF3 and CD229), which is found in less than 10-5 individuals in the general population, underlies TB in three unrelated patients due to selective impairment in IFN-gamma production by TH1* cells. TH1* cells express higher levels of LY9 than other CD4+ T cells. Mechanistically, LY9 polarizes na & iuml;ve CD4+ T cells toward memory TH1* cells by inducing T-bet via signaling lymphocytic activation molecule (SLAM)-associated protein (SAP) and ROR gamma T (thymus-specific retinoid-related orphan receptor gamma) without SAP. LY9 costimulation enhances TCR-driven IFN-gamma production of memory TH1*, but not TH1, cells in a T cell-intrinsic manner via NFAT1 (nuclear factor of activated T cells 1) and ROR gamma T. LY9 is likely to govern an optimal TH1* cell- and IFN-gamma-dependent protective immunity to M.tb in humans.

We talk to authors Sukrit Silas and Heloise Carion about their paper "Activation of bacterial programmed cell death by phage inhibitors of host immunity" (in this issue of Molecular Cell) and the mutagenesis screen that it arose from.

Leukopoiesis is lethally arrested in mice lacking the master transcriptional regulator PU.1. Depending on the animal model, subtotal PU.1 loss either induces acute myeloid leukemia or arrests early B-cell and dendritic-cell development. Although humans with absolute PU.1 deficiency have not been reported, a small cadre of congenital agammaglobulinemia patients with sporadic, inborn PU.1 haploinsufficiency was recently described. To better estimate the penetrance, clinical complications, immunophenotypic features, and malignancy risks of PU.1-mutated agammaglobulinemia (PU.MA), a collection of 134 novel or rare PU.1 variants from publicly available databases, institutional cohorts, previously published reports, and unsolved agammaglobulinemia cases were functionally analyzed. In total, 25 loss-of-function (LOF) variants were identified in 33 heterozygous carriers from 21 kindreds across 13 nations. Of individuals harboring LOF PU.1 variants, 22 were agammaglobulinemic, 5 displayed antibody deficiencies, and 6 were unaffected, indicating an estimated disease penetrance of 81.8% with variable expressivity. In a cluster of patients, disease onset was delayed, sometimes into adulthood. All LOF variants conveyed effects via haploinsufficiency, either by destabilizing PU.1, impeding nuclear localization, or directly interfering with transcription. PU.MA patient immunophenotypes consistently demon strated B-cell, conventional dendritic-cell, and plasmacytoid dendritic-cell deficiencies. Associated infectious and noninfectious symptoms hewed closely to X-linked agammaglobulinemia and not monogenic dendritic-cell deficiencies. No carriers of LOF PU.1 variants experienced hematologic malignancies. Collectively, in vitro and clinical data indicate heterozygous LOF PU.1 variants undermine humoral immunity but do not convey strong leukemic risks.

In the common cellular space, hundreds of binding reactions occur reliably and enable this remarkable compatibility have not yet been adequately elucidated. In order to delineate these principles, we consider the intracellular sensing of transition metals in bacteria-an integral part of cellular metal homeostasis. Protein cytosolic sensors typically interact with metals through three types of lateral chain residues, containing oxygen, nitrogen, or sulfur. The very existence of complete sets of mutually compatible sensors is a nontrivial problem solved by evolution, since each metal sensor has to bind to its cognate metal without being "mismetallated" by noncognate competitors. Here, based solely on theoretical considerations and limited information about binding transition-metal sensor sets are severely limited in their number by compatibility requirements, leaving only a handful of possible sensor compositions for each transition metal. Our theoretical results turn out to be broadly consistent with experimental data crucial role in the organization and functioning of intracellular processes.

The cGAS-STING pathway, well-known to elicit interferon (IFN) responses, is also a key inducer of autophagy upon virus infection or other stimuli. Whereas the mediators for cGAS-induced IFN responses are well characterized, much less is known about how cGAS elicits autophagy. Here, we report that TRIM23, a unique TRIM protein harboring both ubiquitin E3 ligase and GTPase activity, is crucial for cGAS-STING-dependent antiviral autophagy. Genetic ablation of TRIM23 impairs autophagic control of HSV-1 infection. HSV-1 infection or cGAS-STING stimulation induces TBK1-mediated TRIM23 phosphorylation at S39, which triggers TRIM23 autoubiquitination and GTPase activity and ultimately elicits autophagy. Fibroblasts from a patient with herpes simplex encephalitis heterozygous for a dominant-negative, kinase-inactivating TBK1 mutation fail to activate autophagy by TRIM23 and cGAS-STING. Our results thus identify the cGAS-STING-TBK1-TRIM23 axis as a key autophagy defense pathway and may stimulate new therapeutic interventions for viral or inflammatory diseases.

Crimean-Congo hemorrhagic fever virus (CCHFV) is an enveloped, negative-sense RNA virus that is spread by ticks across Europe, Africa, and Asia and causes a lethal disease in humans (similar to 30%-40% case fatality). There are currently no approved vaccines or therapeutics. Antibody-based therapeutics targeting the CCHFV surface glycoproteins Gn and Gc, which are responsible for viral attachment and fusion during entry, are a promising therapeutic approach. We previously isolated three broadly neutralizing Gc-targeting human monoclonal antibodies (mAbs) and showed certain cocktails of these mAbs demonstrated synergistic virus neutralization. Furthermore, physical linkage of two of these mAbs into a dual variable domain (DVD) bispecific antibody (bsAb) DVD-121-801 resulted in improved neutralization and therapeutic protection against a lethal CCHFV challenge in mice. However, the molecular requirements for the activity of DVD-121-801, and why it is augmented over monospecific parental mAbs, remain the topic of investigation. Here, we generated a new panel of bsAb variants of DVD-121-801 to explore the spacing and avidity requirements and further optimize its protective efficacy against divergent CCHFV isolates. We evaluated these variants for neutralization, fusion inhibition, and protection with virus-like particles, authentic viruses, and in vivo challenge studies. We found that neutralization potency was relatively unaffected by spacing or identity of variable domains within the bsAb, but that one next-generation design employing longer and more flexible linkers between variable domains (DVD-121-801GS) had a greater breadth of therapeutic protection. Our efforts highlight the importance of antibody avidity and lead to an improved bsAb variant of DVD-121-801 for further therapeutic development. IMPORTANCE Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus endemic to Europe, Africa, and Asia that causes severe disease in humans (30%-40% case fatality). There are currently no approved vaccines or therapeutics. In prior work, physical linkage of two Gc-specific monoclonal antibodies (mAbs) targeting distinct epitopes into a dual variable domain (DVD) bispecific antibody (bsAb), termed DVD-121-801, resulted in potent neutralization in vitro and therapeutic protection in vivo. Here, a panel of variants of this bsAb was developed and evaluated for neutralization potency, fusion inhibition, and therapeutic efficacy, and our work shows this panel to be effective against multiple isolates of CCHFV. Furthermore, incorporating longer, more flexible linkers between variable domains resulted in a lead candidate with improved activity and therapeutic potential compared to the parental bsAb. Utilizing this panel, we also explored the contribution of antibody avidity in antibody-mediated protection against CCHFV infection.

Gating in voltage-dependent ion channels is regulated by the transmembrane voltage. This form of regulation is enabled by voltage-sensing domains (VSDs) that respond to transmembrane voltage differences by changing their conformation and exerting force on the pore to open or close it. Here, we use cryogenic electron microscopy to study the neuronal K(v)2.1 channel in lipid vesicles with and without a voltage difference across the membrane. Hyperpolarizing voltage differences displace the positively charged S4 helix in the voltage sensor by one helical turn (similar to 5 angstrom). When this displacement occurs, the S4 helix changes its contact with the pore at two different interfaces. When these changes are observed in fewer than four voltage sensors, the pore remains open, but when they are observed in all four voltage sensors, the pore constricts. The constriction occurs because the S4 helix, as it displaces inward, squeezes the right-handed helical bundle of pore-lining S6 helices. A similar conformational change occurs upon hyperpolarization of the EAG1 channel but with two helical turns displaced instead of one. Therefore, while K(v)2.1 and EAG1 are from distinct architectural classes of voltage-dependent ion channels, called domain-swapped and non-domain-swapped, the way the voltage sensors gate their pores is very similar.