Publications by authors named "Shawn Berens"

As part of the non-clinical safety package characterizing bamlanivimab (SARS-CoV-2 neutralizing monoclonal antibody), the risk profile for antibody-dependent enhancement of infection (ADE) was evaluated in vitro and in an African green monkey (AGM) model of COVID-19. In vitro ADE assays in primary human macrophage, Raji, or THP-1 cells were used to evaluate enhancement of viral infection. Bamlanivimab binding to C1q, FcR, and cell-based effector activity was also assessed.

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Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) poses a public health threat for which preventive and therapeutic agents are urgently needed. Neutralizing antibodies are a key class of therapeutics that may bridge widespread vaccination campaigns and offer a treatment solution in populations less responsive to vaccination. Here, we report that high-throughput microfluidic screening of antigen-specific B cells led to the identification of LY-CoV555 (also known as bamlanivimab), a potent anti-spike neutralizing antibody from a hospitalized, convalescent patient with coronavirus disease 2019 (COVID-19).

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With the growth of monoclonal antibodies and other proteins as major modalities in the pharmaceutical industry, there has been an increase in pharmacology and toxicity testing of biotherapeutics in animals. Animals frequently mount an immune response to human therapeutic proteins. This can result in asymptomatic anti-drug antibody formation, immune complexes that affect drug disposition and/or organ function such as kidney, cytokine release responses, fatal hypersensitivity, or a range of reactions in between.

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Unlabelled: SARS-CoV-2 poses a public health threat for which therapeutic agents are urgently needed. Herein, we report that high-throughput microfluidic screening of antigen-specific B-cells led to the identification of LY-CoV555, a potent anti-spike neutralizing antibody from a convalescent COVID-19 patient. Biochemical, structural, and functional characterization revealed high-affinity binding to the receptor-binding domain, ACE2 binding inhibition, and potent neutralizing activity.

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The microgravity conditions of prolonged spaceflight are known to result in skeletal muscle atrophy that leads to diminished functional performance. To assess if inhibition of the growth factor myostatin has potential to reverse these effects, mice were treated with a myostatin antibody while housed on the International Space Station. Grip strength of ground control mice increased 3.

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Animal models of human disease are commonly utilized to gain insight into the potential efficacy and mode of action of novel pharmaceuticals. However, conventional (healthy) rodent and nonrodent models are generally utilized in nonclinical safety testing. Animal models of human disease may be helpful in understanding safety risks of compounds in nonclinical or clinical development, with their greatest value being in targeted or hypothesis-driven studies to help understand the mechanism of a particular toxicity.

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Babesia bovis is an apicomplexan tick-transmitted pathogen of cattle imposing a global risk and severe constraints to livestock health and economic development. The complete genome sequence was undertaken to facilitate vaccine antigen discovery, and to allow for comparative analysis with the related apicomplexan hemoprotozoa Theileria parva and Plasmodium falciparum. At 8.

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Antigenic polymorphism is a defining characteristic of the Babesia bovis variable merozoite surface antigen (VMSA) family. Sequence analysis strongly suggests that recombination between virulent strains contributes to VMSA diversity. While meiosis during the aneuploid stage of the parasite's life cycle in the tick vector Rhipicephalus (Boophilus) microplus is the most probable source of interstrain recombination, there is no definitive evidence that coinfection of the mammalian host or R.

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A hypervariable region (HVR) previously identified in the carboxy-terminal one-third of the Babesia bovis variable merozoite surface antigen family was more extensively analyzed in merozoite surface antigen 1 (MSA-1) from 16 strains and isolates. The MSA-1 HVR is proline rich and contains three semiconserved motifs nearly identical to those described for the related family member MSA-2. Two MSA-1-specific monoclonal antibodies previously shown to be reactive with the merozoite surface bound to a recombinant construct encoding the HVR, indicating that the HVR is surface exposed and accessible to antibody binding.

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The merozoite surface antigen 2 (MSA-2) proteins of Babesia bovis are members of the variable merozoite surface antigen (VMSA) family that have been implicated in erythrocyte invasion and are important targets for antibody-mediated blocking of invasion. Extensive sequence variation in another VMSA member, MSA-1, has been shown in all vaccine breakthrough isolates. To test the hypothesis that the msa-2 genes of vaccine breakthrough isolates would also encode a diverse set of proteins, the complete msa-2 locus was characterized from 12 Australian B.

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