Effect of Tezepelumab on the Humoral Immune Response to Seasonal Quadrivalent Influenza Vaccination in Patients with Moderate to Severe Asthma: The Phase 3b VECTOR Study.

INTRODUCTION: Annual influenza vaccinations are recommended for adolescents and adults with moderate to severe asthma. This study investigated the effect of tezepelumab, a human monoclonal antibody that blocks the activity of thymic stromal lymphopoietin, on the humoral immune response to the quadrivalent seasonal influenza vaccine in patients with moderate to severe asthma. METHODS: VECTOR was a phase 3b, randomized, multicenter, double-blind, parallel-group, placebo-controlled study. Adolescents (aged 12-17 years) and young adults (aged 18-21 years) with moderate to severe asthma were enrolled across 15 centers in the USA. Patients received tezepelumab 210 mg or placebo subcutaneously at weeks 0, 4, 8, and 12, and a single dose of inactivated quadrivalent seasonal influenza vaccine at week 12 before receiving study treatment. Immediately before vaccination and at 4 weeks postvaccination (week 16), strain-specific antibody responses were assessed for four influenza antigens by hemagglutination inhibition (HAI) and microneutralization (MN) assays. Safety was assessed. RESULTS: Seventy patients were randomized to tezepelumab (n = 35) or placebo (n = 35). There were no meaningful differences in HAI or MN antibody responses between treatment groups at week 16. HAI assay geometric mean fold rises (GMFRs) for influenza strains were 1.76-7.34 for tezepelumab and 1.46-4.75 for placebo. MN assay GMFRs were 4.00-14.56 for tezepelumab and 3.56-10.62 for placebo. In the HAI assay, a fourfold or larger rise in antibody titer from weeks 12 to 16 occurred in 15.2-78.8% and 15.2-51.5% of tezepelumab and placebo recipients, respectively, and 97.0-100% of patients in both treatment groups achieved an antibody titer of at least 40 at week 16. No unexpected safety findings occurred. CONCLUSION: There was no observed suppression of the humoral immune response after influenza vaccination in adolescents and young adults with moderate to severe asthma treated with tezepelumab. Therefore, the influenza vaccine can be administered to this patient population during tezepelumab treatment. GOV IDENTIFIER: NCT05062759.

Strength-mass scaling law governs mass distribution inside honey bee swarms.

To survive during colony reproduction, bees create dense clusters of thousands of suspended individuals. How does this swarm, which is orders of magnitude larger than the size of an individual, maintain mechanical stability? We hypothesize that the internal structure in the bulk of the swarm, about which there is little prior information, plays a key role in mechanical stability. Here, we provide the first-ever 3D reconstructions of the positions of the bees in the bulk of the swarm using x-ray computed tomography. We find that the mass of bees in a layer decreases with distance from the attachment surface. By quantifying the distribution of bees within swarms varying in size (made up of 4000-10,000 bees), we find that the same power law governs the smallest and largest swarms, with the weight supported by each layer scaling with the mass of each layer to the [Formula: see text] power. This arrangement ensures that each layer exerts the same fraction of its total strength, and on average a bee supports a lower weight than its maximum grip strength. This illustrates the extension of the scaling law relating weight to strength of single organisms to the weight distribution within a superorganism made up of thousands of individuals.

Functionality and Performance of an Accessorized Pre-Filled Syringe and an Autoinjector for At-Home Administration of Tezepelumab in Patients with Severe, Uncontrolled Asthma.

BACKGROUND: Tezepelumab is an anti-thymic stromal lymphopoietin monoclonal antibody in development for the treatment of severe asthma. This study assessed the functionality and performance of an accessorized pre-filled syringe (APFS) and an autoinjector (AI) for administration of tezepelumab in the clinic and at home. METHODS: This phase 3, multicenter, randomized, open-label, parallel-group study (PATH-HOME, ClinicalTrials.gov identifier: NCT03968978) was conducted in patients aged 12-80 years with asthma that was uncontrolled despite treatment with medium- to high-dose inhaled corticosteroids plus at least one additional controller medication. Patients received six subcutaneous doses of tezepelumab 210 mg via APFS or AI. The first dose was administered by a healthcare professional, and patients or caregivers administered subsequent doses. First, second, third and final doses were administered in the clinic; fourth and fifth doses were administered at home. The primary endpoint was the proportion of successful administrations of tezepelumab. Secondary endpoints included the functionality and performance of the devices, Asthma Control Questionnaire (ACQ)-6 score, pharmacokinetics and safety. RESULTS: Overall, 216 patients were randomized (APFS, n=111; AI, n=105). Tezepelumab was successfully administered via APFS by 91.7% of the participants (100/109) and via AI by 92.4% (97/105). Overall, 95.4-97.1% of at-home administrations were successful across device groups. Malfunction occurred in 6 of 655 dispensed APFSs and 5 of 624 dispensed AIs. Clinically meaningful improvements in ACQ-6 score were observed after 24 weeks in 81.1% and 76.2% of the patients in the APFS and AI groups, respectively. Tezepelumab pharmacokinetics were consistent between device groups and with previous studies. The most common adverse event was nasopharyngitis (9.3%). Injection-site reactions occurred in 5.7% and 0% of the patients in the AI and APFS groups, respectively. CONCLUSION: This study demonstrated that the APFS and AI were functional and reliable, and performed equally well at home and in the clinic.

p53 binding to nucleosomal DNA depends on the rotational positioning of DNA response element.

The sequence-specific binding to DNA is crucial for the p53 tumor suppressor function. To investigate the constraints imposed on p53-DNA recognition by nucleosomal organization, we studied binding of the p53 DNA binding domain (p53DBD) and full-length wild-type p53 protein to a single p53 response element (p53RE) placed near the nucleosomal dyad in six rotational settings. We demonstrate that the strongest p53 binding occurs when the p53RE in the nucleosome is bent in the same direction as observed for the p53-DNA complexes in solution and in co-crystals. The p53RE becomes inaccessible, however, if its orientation in the core particle is changed by approximately 180 degrees. Our observations indicate that the orientation of the binding sites on a nucleosome may play a significant role in the initial p53-DNA recognition and subsequent cofactor recruitment.

Efectos de la lactancia materna exclusiva sobre el padrón de crecimiento facial en jóvenes paraguayos / Effects of exclusive breastfeeding on the pattern of facial growth in young Paraguayans

Es indiscutible el papel de la genética sobre el padrón de crecimiento facial, así como la influencia de factores ambientales, los cuales han sido ampliamente investigados. Basados en algunos estudios que consideran la lactancia materna como factor ambiental estimulante para el desarrollo del sistema estomatognático, el presente trabajo denota la influencia de la lactancia materna exclusiva durante un periodo mínimo de seis meses sobre el padrón de crecimiento facial. Para lo cual la muestra fue seleccionada bajo criterios específicos detallados en el marco metodológico, quedando compuesta por 50 telerradiografías de sujetos entre 10 a 15 años de edad, divididas en dos grupos, uno perteneciente a 25 niños sometidos a lactancia materna exclusiva por seis meses y otro perteneciente a 25 individuos sometidos a lactancia mixta o artificial por un promedio mínimo de 6 meses. Se procedió al cálculo del padrón de crecimiento facial midiendo las siguientes variables. Eje Y (ypsilon); FMA; oclusal/SN y SN/GoGn. Los datos fueron analizados observándose que el grupo de lactante exclusivo presentó un mayor número de sujetos con padrón de crecimiento horizontal, el 40% un 36% padrón equilibrado y 24% padrón vertical; mientras que el grupo de lactancia combinada o artificial, el padrón facial predominante fue el vertical de crecimiento con un 72%. A través de la prueba "T" se analizaron los promedios de cada variable, en cada grupo, encontrándose diferencias estadísticamente significativas. Se concluyó que el amamantamiento exclusivo estimula el crecimiento facial hacia adelante, lo cual favorece el buen relacionamiento entre las bases óseas maxilares, teniendo en cuenta que la mandíbula debe cambiar de posición retrusiva tras el nacimiento a una ubicación más anterior; siendo un motivo más de promoción de la lactancia materna exclusiva por un periodo mínimo de 6 meses .

Elucidation of the role of peptide linker in calcium-sensing receptor activation process.

Family 3 G-protein-coupled receptors (GPCRs), which includes metabotropic glutamate receptors (mGluRs), sweet and "umami" taste receptors (T1Rs), and the extracellular calcium-sensing receptor (CaR), represent a distinct group among the superfamily of GPCRs characterized by large amino-terminal extracellular ligand-binding domains (ECD) with homology to bacterial periplasmic amino acid-binding proteins that are responsible for signal detection and receptor activation through as yet unresolved mechanism(s) via the seven-transmembrane helical domain (7TMD) common to all GPCRs. To address the mechanism(s) by which ligand-induced conformational changes are conveyed from the ECD to the 7TMD for G-protein activation, we altered the length and composition of a 14-amino acid linker segment common to all family 3 GPCRs except GABA(B) receptor, in the CaR by insertion, deletion, and site-directed mutagenesis of specific highly conserved residues. Small alterations in the length and composition of the linker impaired cell surface expression and abrogated signaling of the chimeric receptors. The exchange of nine amino acids within the linker of CaR with the homologous sequence of mGluR1, however, preserved receptor function. Ala substitution for the four highly conserved residues within this amino acid sequence identified a Leu at position 606 of the CaR critical for cell surface expression and signaling. Substitution of Leu(606) for Ala resulted in impaired cell surface expression. However, Ile and Val substitutions displayed strong activating phenotypes. Disruption of the linker by insertion of nine amino acids of a random-coiled structure uncoupled the ECD from regulating the 7TMD. These data are consistent with a model of receptor activation in which the peptide linker, and particularly Leu(606), provides a critical interaction for the CaR signal transmission, a finding likely to be relevant for all family 3 GPCRs containing this conserved motif.

A model for PTCH1/Ptch1-associated tumors comprising mutational inactivation and gene silencing.

Mutations of the Sonic hedgehog (SHH) receptor, Patched1 (PTCH1), have been identified in a variety of tumors. PTCH1 is usually considered to be a tumor suppressor gene. However, one normal allele is retained in many tumors. We investigated the mechanism of tumorigenesis in murine heterozygous Ptch1 knock-out mice. Here we show that Ptch1 transcripts, which are consistently overexpressed in tumors in these mice, are derived predominantly from the mutated allele. These transcripts give rise to a mutant protein incapable of pathway inhibition. In contrast, the expression of wild-type transcripts in the tumor is reduced. The transcriptional activity of a Ptch1 promoter is sensitive to methylation. Based on these results, we propose a model, in which tumorigenesis begins with the transcriptional silencing of one PTCH1/Ptch1 allele. This alone has no functional consequences. Upon mutational inactivation of the other allele, the resulting loss of PTCH1/Ptch1 function activates PTCH1/Ptch1 transcription from the non-silenced, i.e. the mutant, allele. These events can occur in an opposite order. This model is consistent with the expression of PTCH1/Ptch1-derived transcripts and proteins found in tumors, with the sensitivity of the murine Ptch1 promoter to methylation, and with the recently reported effect of demethylating agents on Ptch1 expression. These latter agents could be effective in treatment of, at least, some tumors associated with loss of PTCH1 function.

Calcium phosphate transfection.

This unit presents two methods of calcium phosphate-based eukaryotic cell transfection that can be used for both transient and stable transfections. In these protocols, plasmid DNA is introduced to monolayer cell cultures via a precipitate that adheres to the cell surface. A HEPES-buffered solution is used to form a calcium phosphate precipitate that is directly layered onto the cells. For some cells, shocking the cells with glycerol or DMSO improves transfection efficiency. In the alternate high-efficiency method, a BES-buffered system is used that allows the precipitate to form gradually in the medium and then drop onto the cells. While the alternate method is particularly efficient for stable transformation of cells with circular plasmid DNA, both protocols yield similar results for transformation with linear plasmid or genomic DNA, or for transient expression.

Calcium phosphate transfection.

This unit presents two methods of calcium phosphate-based eukaryotic cell transfection that can be used for both transient and stable transfections. In these protocols, plasmid DNA is introduced to monolayer cell cultures via a precipitate that adheres to the cell surface. A HEPES-buffered solution is used to form a calcium phosphate precipitate that is directly layered onto the cells. For some cells, shocking the cells with glycerol or DMSO improves transfection efficiency. In the alternate high-efficiency method, a BES-buffered system is used that allows the precipitate to form gradually in the medium and then drop onto the cells. While the alternate method is particularly efficient for stable transformation of cells with circular plasmid DNA, both protocols yield similar results for transformation with linear plasmid or genomic DNA, or for transient expression.