Selective suppression of de novo SARS-CoV-2 vaccine antibody responses in patients with cancer on B cell-targeted therapy.

We assessed vaccine-induced antibody responses to the SARS-CoV-2 ancestral virus and Omicron variant before and after booster immunization in 57 patients with B cell malignancies. Over one-third of vaccinated patients at the pre-booster time point were seronegative, and these patients were predominantly on active cancer therapies such as anti-CD20 monoclonal antibody. While booster immunization was able to induce detectable antibodies in a small fraction of seronegative patients, the overall booster benefit was disproportionately evident in patients already seropositive and not receiving active therapy. While ancestral virus- and Omicron variant-reactive antibody levels among individual patients were largely concordant, neutralizing antibodies against Omicron tended to be reduced. Interestingly, in all patients, including those unable to generate detectable antibodies against SARS-CoV-2 spike, we observed comparable levels of EBV- and influenza-reactive antibodies, demonstrating that B cell-targeting therapies primarily impair de novo but not preexisting antibody levels. These findings support rationale for vaccination before cancer treatment.

A simple colorimetric experiment using mammalian cell culture to study metabolism.

The goal of this laboratory exercise is to give upper-level undergraduate students an introduction to sterile technique in mammalian cell culture and metabolism. The experiment can be completed within a 3-h lab period and can be performed either in conjunction with other biochemistry/metabolism experiments or used as a stand-alone experiment. In this experiment, students are tasked with relating the acidification of cell culture medium to metabolism in order to elucidate the mechanism of action for a compound. Students can relate their experimental results to topics covered on glycolysis and oxidative phosphorylation in upper-level biochemistry classes as well as gain valuable experience relating metabolism to drug discovery.