Figure 5

Inhibition ELISA. Inhibition of binding of the phage displayed scFv H2 in a competitive ELISA. Purified BTV serotype 10 particles were immobilised directly on a plastic surface. The samples to be tested for inhibition were then added, followed by the phage displayed scFv H2, an anti-pVIII monoclonal antibody and an enzyme-labelled anti-mouse IgG immunoglobulin. The shaded bars depict the average absorbance value of two determinations while the upper and lower values are shown by the error bars. Test samples used in the inhibition step were: (a) 2% solution of fat-free milk; (b-d) three different non-immune rabbit sera; (e) 1/9 and (f) 1/81 dilutions of anti-BTV serotype 4 rabbit immune serum; (g) 1/9 and (h) 1/81 dilutions of anti-BTV serotype 10 rabbit antiserum; (i) 1/9 and (j) 1/81 dilutions of non-immune sheep serum; (k) 1/9 and (l) 1/81 dilutions of sheep antiserum directed against BTV serotype 2; (m) 1/9 and (n) 1/81 dilutions of sheep antiserum against BTV serotype 4; (o) 1/9 and (p) 1/81 dilutions of BTV serotype 9-specific sheep antisera. The background binding of non-fusion phage to the immobilised BTV serotype 10 is shown by (q).