Immortalized Rhesus macaque Bcl-6/Bcl-xL Stable B Cell Lines as Tools for HIV Antibody Discovery

Scientists at NIAID have developed two immortalized stable B cell lines from rhesus macaques that can have value as research tools for the discovery of neutralizing antibodies of simian origin against HIV and that may have value in the development of an HIV vaccine. These B cell lines encode human Bcl-6 and Bcl-xL proteins, which are major regulators of apoptosis. These B cell lines are derived from the lymph node of a rhesus macaque (RM) that was infected with SHIV.CH505. It was discovered that, unlike in humans, rhesus macaque B cells from lymph nodes are more effectively immortalized than B cells from Peripheral Blood Mononuclear Cells (PBMCs).

After sample collection and cryopreservation, pro B cells were isolated, sorted by flow cytometry for populations of interest, then activated with CD40 ligand and RM IL-2 followed by transduction with a retroviral vector encoding Bcl-6, Bcl-xL, and green fluorescent protein (GFL), thereby creating immortalized clonal lines. Two clones were down selected for their in vitro neutralizing ability against HIV pseudovirus CH505.