CD4 and infection: Along these lines, we have shown that a recombinant Mycobacterium bovis Calmette-Guerin (BCG) expressing hRSV Nucleoprotein (N) (rBCG-N-hRSV) primes hRSV-specific CD4+ T cells and CD8+ CTLs that promote antiviral immunity, reduce neutrophil infiltration, and prevent lung damage in a mouse model of infection (24, 25).