Identification and characterisation of multiple linear B cell protectopes in the respiratory syncytial virus G protein

Respiratory syncytial virus (RSV) is an important respiratory pathogen in man. against which no vaccine is available. However. recent evidence suggests that antibodies to the RSV F and G proteins may play an important role in disease prevention. We previously demonstrated that BBG2Na. a subunit vaccine candidate including residues 130-230 of the Long strain G protein, protects rodents against RSV challenge. Using a panel of monoclonal antibodies (MAb) and synthetic peptides, five linear B cell epitopes were identified that mapped to residues 152-163. 165-172. 171-187(two over-lapping epitopes) and 196-204. Antibody passive transfer and peptide immunisation studies revealed that all were protective. Pepscan analyses of anti-RSV-A and BBG2Na murine polyclonal sera suggested stronger immunogenicity of some protective epitopes (protectopes) in the context of BBG2Na compared with live virus. However. all the identified murine B cell protectopes were conserved ill RSV seropositive humans. Should these protectopes correspond with protection in humans. BBG2Na may constitute a very interesting vaccine candidate against RSV. (C) 2001 Elsevier Science Ltd. All rights reserved.