Application of B cell immortalization for the isolation of antibodies and B cell clones from vaccine and infection settings

Boswell, K. L.; Watkins, T.; Cale, E. M.; Samsel, J.; Andrews, S. F.; Ambrozak, D. R.; Driscoll, J. I.; Messina, M. A.; Narpala, S.; Hopp, C. S.; Cagigi, A.; Casazza, J. P.; Yamamoto, T.; Zhou, T.; Schief, W. R.; Crompton, P. D.; Ledgerwood, J. E.; Connors, M.; Gama, L.; Kwong, P. D.; McDermott, A.; Mascola, J. R.; Koup, R. A.

doi:10.1101/2022.03.29.485179

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bioRxiv · 10.1101/2022.03.29.485179

Application of B cell immortalization for the isolation of antibodies and B cell clones from vaccine and infection settings

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Abstract

The isolation and characterization of neutralizing antibodies from infection and vaccine settings will inform future vaccine design, and methodologies that streamline the isolation of antibodies and the generation of B cell clones are of great interest. Retroviral transduction to express Bcl-6 and Bcl-xL in primary B cells has been shown to promote long-term B cell survival and antibody secretion in vitro, and can be used to isolate antibodies from memory B cells. The application of this methodology to B cell subsets from tissues and to B cells from individuals with chronic infection has not been extensively characterized. Here, we characterize Bcl-6/Bcl-xL B cell immortalization across multiple tissue types and B cell subsets in healthy and HIV-1 infected individuals, as well as individuals recovering from malaria. In HIV-1- and malaria-uninfected donors, naive and memory B cell subsets from PBMC and tonsil tissue transformed with similar efficiencies, and displayed similar characteristics after transformation with respect to their longevity and immunoglobulin secretion. In HIV-1-viremic individuals or in individuals after malaria infection, the CD27-CD21- memory B cell subsets transformed with lower efficiencies compared to the CD27+CD21+ populations, but following transformation B cells expanded and secreted IgG with similar efficiency. Using B cells from HIV-1-infected individuals, we combined Bcl-6/Bcl-xL B cell immortalization with a HIV-1 microneutralization assay to isolate broadly neutralizing antibodies related to VRC13 and VRC38.01. Overall, Bcl-6/Bcl-xL B cell immortalization can be used to isolate antibodies and generate B cell clones from multiple different B cell populations, albeit with different efficiencies.

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Boswell, K. L., Watkins, T., Cale, E. M., Samsel, J., Andrews, S. F., Ambrozak, D. R., Driscoll, J. I., Messina, M. A., Narpala, S., Hopp, C. S., Cagigi, A., Casazza, J. P., Yamamoto, T., Zhou, T., Schief, W. R., Crompton, P. D., Ledgerwood, J. E., Connors, M., Gama, L., Kwong, P. D., McDermott, A., Mascola, J. R., Koup, R. A.. 2022-03-30. Application of B cell immortalization for the isolation of antibodies and B cell clones from vaccine and infection settings. https://doi.org/10.1101/2022.03.29.485179

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