Antigenic landscape of Nipah virus attachment glycoprotein analysis reveals a protective immunodominant epitope across species.

Nipah virus (NiV) and Hendra virus (HeV), two highly pathogenic Henipaviruses (HNVs), pose a significant public health threat. The attachment glycoprotein (G) plays a crucial role in viral attachment and entry, making it an attractive target for vaccine and therapeutic antibody development. However, the antigenic landscape and neutralization sensitivity of the diverse HNV G proteins remain poorly defined. Here, we systematically characterize 27 monoclonal antibodies (mAbs) elicited by NiV G head (GH) nanoparticle-immunized mice. Among these, 25 mAbs exhibit neutralizing activity against two major NiV strains, NiV-Malaysia and NiV-Bangladesh, with five mAbs also cross-inhibiting HeV infection. Notably, mAbs from two distinct groups conferred complete protection to hamsters against lethal NiV-Malaysia challenge. Structural analysis of NiV GH in complex with representative Fabs reveals four non-overlapping epitopes, including two novel antigenic sites and one public protective epitope shared across species. MAbs targeting the novel sites bind to the top or side faces of G protein's β-propeller and inhibit viral infection by blocking either receptor engagement or membrane fusion. MAbs recognizing the public epitope block the receptor binding directly. Our study provides a comprehensive antigenic map of the NiV GH and offers new insights and opportunities for antibody-based therapies and rational vaccine development.