HIV inhibition of cell free HIV
virus infection by HIV-1 gp120 Antiserum (PB1) and Silver Nanoparticles. Serial two-fold dilutions of HIV-1 gp120 Antiserum (PB1) was added to 105 TCID50 of HIV-1IIIB cell-free virus. After incubation for 5 minutes, they were added with or without silver nanoparticles at 1 mg/mL. Then the mixture was placed into 96-well plates with indicator cells (U373-MAGI-CXCR4CEM) at a final 0.2-0.5 m.o.i. Assessment of HIV-1 infection was made with a luciferase-based assay. The percentage of residual infectivity after treatment was calculated with respect to the positive control of untreated virus. The assay was performed in triplicate; the data points represent the mean, and the solid lines are nonlinear regression curves done with SigmaPlot 10.0 software. By means of Mann- Whitney Rank Sum test we compared the difference in the median values between the two groups (only AgNPs and AgNPs with antibody to HIV-1 gp120 Antiserum PB1) is not great enough to exclude the possibility that the difference is due to random sampling variability; there is not a statistically significant difference (P < 0.065).