The Respiratory Syncytial Virus (RSV) nucleoprotein (N protein) is an approximately 43 kDa RNA-binding protein that encapsidates the viral genome to form ribonucleoprotein (RNP) complexes essential for viral replication and transcription. Highly conserved across RSV subgroups A and B, the N protein interacts with the phosphoprotein (P) and RNA-dependent RNA polymerase (L) to coordinate RNA synthesis within cytoplasmic inclusion bodies. As one of the most abundant and immunodominant RSV antigens, N protein elicits robust humoral and cellular immune responses and serves as a critical target for RSV research. Catalina’s RSV Nucleoprotein antibodies deliver high sensitivity and specificity, supporting research in viral detection, pathogenesis, and vaccine development.