We evaluated the immunogenicity of a CCD-deleted G-ectodomain [REG ΔCCD; with residues 172–186 replaced by a (Gly4Ser)2 linker], and two large G subdomains covering the N-terminus (REG 67–163) and C-terminus (REG 187–298) upstream and downstream of the CCD, respectively, that were identified as immunodominant in the epitope profiling of post-RSV primary infection human sera (Fig 1 panels A-B). The gene discussed is REG1A; the disease is infection.