B cell responses are impaired in HIV-infected individuals. Elias Haddad and colleagues now report that follicular helper T (TFH) cells, which are crucial for the maturation of B cell memory and development of high-affinity antibodies, are functionally impaired upon interaction with lymph node germinal center B cells from HIV-infected individuals. The interaction of the inhibitory molecule PD-1 on TFH cells with its ligand PD-L1, which is elevated on germinal center B cells in HIV-infected lymph nodes, impairs TFH cell proliferation and antibody production by B cells, thus providing insight into humoral dysfunction in HIV infection.
- Rafael A Cubas
- Joseph C Mudd
- Elias K Haddad
