Figure 2

Antibody responses in RHDV and RHDV2 vaccinated rabbits analyzed by indirect ELISA. A Titres of sera (n = 4) from rabbits immunized with RHDV VLPs. Each sample is represented on a coordinate graph showing its titre for RHDV on the x-axis and for RHDV2 on the y-axis. For the determination of serum titres, seven serial three-fold dilutions starting from 1/10 000 were tested by ELISA for reactivity against RHDV and RHDV2 VLPs independently in duplicate samples. OD measurements were blank-corrected and titre extrapolated as the dilution at which they reached an arbitrary OD value (0.240) corresponding to that obtained by the mean + 2 times the standard deviation of 12 serum samples from non-vaccinated animals assayed at a 1/30 dilution. This OD value was initially established as threshold to classify each serum as negative or positive. All calculations were performed using GraphPad software. B Titres of sera from 8 week old rabbits vaccinated with ARVILAP (n = 2) or 4 week old rabbits vaccinated with FILAVAC (n = 5) or NOVARVILAP (n = 5), respectively. ELISA assays were performed as described above using a dilution range starting from 1/30. Representation and calculations are as in panel A. Procedures involving obtainment of animal samples were carried out under EU guidelines and supervised and approved by the institutional ethical review committee.