Persistent T Cell Immunity Following Nipah Virus Infection: Evidence From Malaysian Survivors.

Nipah virus (NiV) induces strong humoral immunity, but the durability of NiV-specific memory T-cell responses remains unclear. We characterized cellular immunity approximately 25 years after infection in 4 survivors of the 1998 Malaysian outbreak. PBMCs were stimulated with overlapping peptide mini-pools spanning the NiV fusion (NiV-F) and attachment (NiV-G) glycoproteins, and responses were assessed using enzyme-linked immune absorbent spot and intracellular cytokine staining. Durable cytokine-producing T-cell responses were detected, with immunodominant epitopes in the NiV-G ectodomain. Survivors with neurological sequelae exhibited stronger T-cell responses and cognitive impairment, highlighting persistent cellular immunity decades after infection with implications for vaccine development.