***** Right, but that was to produce IL-6 mice in 2017 for a different research purpose that has nothing to do with their Covid monoclonal antibody.******
Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced that Science has accepted for publication two papers describing the creation of its novel two-antibody cocktail, REGN-COV2, and its potential to diminish risk of viral escape by effectively binding to the virus’s critical spike protein in two separate, non-overlapping locations. The publications will be available online on Monday. Regeneron also announced today that REGN-COV2 has entered human clinical trials
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The first paper entitled “Studies in humanized mice and convalescent humans yield a SARS-CoV-2 antibody cocktail” describes Regeneron’s parallel efforts using both humanized VelocImmune® mice and blood samples from recovered COVID-19 patients to generate a large and diverse collection of antibodies targeting multiple different regions of the critical receptor-binding domain (RBD) of the SARS-CoV-2 spike protein. The spike protein on the virus cell surface binds to the host cell and is required for infectivity. By blocking its interaction with the host cell, antibodies are able to neutralize the virus and block infection. Regeneron scientists selected pairs of highly potent individual antibodies that simultaneously and non-competitively bind to the RBD. Regeneron pursues a multi-antibody cocktail approach for infectious diseases in order to decrease the potential for the virus to escape.
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Studies in humanized mice and convalescent humans yield a SARS-CoV-2 antibody cocktail
“ In this work, we describe parallel high-throughput efforts using both mice and humans to generate antibodies against the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The ability to derive antibodies using genetically humanized VI mice as well as B cells derived from convalescent patients enabled us to isolate a very large collection of fully human antibodies with diverse sequences, binding properties, and antiviral activities.”
https://www.science.org/doi/full/10.1126/science.abd0827
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Did you miss this? "Studies in humanized mice and convalescent humans"... I can guarantee that the convalescent humans were not aborted.
You are making a category error in thinking there is only one way to humanize mice when there are many and most of them use adult sourced donations. All of the are disease specific. You aren’t going to use a humanized cancer mouse to study infectious diseases.
There would literally be no purpose in using fetal tissue in development because B cell immunity remains immature until age two. Fetuses pretty much have nothing, it’s all maternal immunity until 6 months or so.