Jianliang Xu, Ph.D., received his doctoral degree from Nanjing University, School of Life Sciences, in China where he studied the transcription regulation of oncogene protein tyrosine phosphatase 4A3 (PTP4A3/PRL-3). Subsequently, Dr. Xu studied the molecular mechanism of immunoglobulin gene diversification under the mentorship of Professor Tasuku Honjo at Kyoto University. He joined the Laboratory of Lymphocyte Nuclear Biology at the NIAMS in 2014, where he is now a Research Fellow.
Dr. Xu’s research on B lymphocytes has expanded from deciphering the mechanism of antibody diversification and maturation in cell culture models to establishing experimental mouse models and creating novel tools for antibody drug development. He has developed knock-in mouse strains to study transcription factors dynamic in primary B cells. Recently, he has engineered a camelized mouse model (nanomice, NIH Employee Invention Report E-209-2020-0) in which B cells no longer express conventional heavy/light chain-paired IgM and IgG1. Instead, both IgM and IgG1 are heavy chain-only, and their variable domains are from camelid animals. Using llamas and the novel nanomouse model, Dr. Xu identified two groups of nanobodies that can potently neutralize SARS-CoV-2 and its circulating variants.
Dr. Xu's long-term goal is to establish efficient nanobody development platforms and use them to develop nanobodies that broadly neutralize viruses that cause infectious diseases such as COVID-19, AIDS, influenza, etc. These platforms will be based on heavy chain-only antibody-producing animals, such as llamas and engineered nanomice, as well as potential new versions of mouse models. Gaining knowledge of how to elicit strong and preferable immune responses in these animal models (upstream vaccine design) and how to extract and optimize functional nanobodies (downstream antibody drug production) will be the critical component of the platforms.