aValues in bold represent significant neutralization titers (IC50 μg/mL) that are at least three times greater than those observed against the negative control (aMLV). Effect of amino acid substitutio
aNeutralization titer is expressed as the reciprocal of the antiserum dilution and was determined as the highest dilution of antiserum that protected HEp-2 cell monolayers from a visually observable C
