Fig. 3: RSVL305I is more resistant to infant serum neutralization than RSVWT.
a, b RSV WT (blue) and RSV L305I (red) neutralization susceptibility to human sera were compared using sera collected from RSV-A or RSV-B infected infants. RSV WT and RSV L305I viruses at an MOI of 0.3 were incubated for 1 h with infant serum diluted to 15 μg/mL, 75 μg/mL, or 150 μg/mL of IgG antibody followed by infection of HeLa cells. Infectious virus was determined by GFP expression using flow cytometry (n = 2). a, percent inhibition was determined for 15 sera samples by comparison to a virus untreated control. b total percent inhibition for all sera samples. Statistical significance was determined using a paired two-tailed t-test (****p < 0.0001). c, d complete EC50 curves were conducted for two representative sera samples (n = 2) c, RSV-A50 and d, RSV-B18. Sera was diluted down 5-fold from a starting dilution of 0.07 and incubated with RSV WT and RSV L305I viruses at an MOI of 0.3 prior to infecting HeLa cells. Percent inhibition was determined by GFP expression by flow cytometry relative to a virus alone control. EC50 values for RSV WT and RSV L305I are indicated at the top left of each graph. Data were fit using a non-linear regression curve and EC50 values were compared using the extra sum-of-squares F test.
