Susceptibility of Gecko Cell Line for Cultivation and Adaptation of Infectious Bursal Disease Virus as an Experimental Vaccine

Nowadays, vaccination is the primary and most effective method for preventing and controlling Infectious bursal disease virus (IBDV). A study examined the potential of a new Gecko cell line (Z1) for cultivating IBDV due to evolutionary similarities between birds and reptiles. After observing complete cytopathic effects (CPE), virus titre was determined using the TCID50 assay, and viral replication was confirmed using an RT-PCR test. In the next step, 150 broiler chickens (15 days old) were randomly divided into three equal groups for immune response measurements: G1: immunized/commercial vaccine, G2: immunized/experimental vaccine and G3: control. Antibody responses and the bursal index were evaluated on different days post-immunization. On the basis of the results, CPE of the virus was noticeable from the first passage, becoming complete by the second passage, and an infectious titre of the virus was 10^7.1. Antibodies titres in both vaccinated groups differed significantly (p < 0.05) from the control group 21 days post-immunization. The bursal index did not significantly differ among the vaccinated and control groups at different times. Overall, this research is the first successful report on cultivating IBDV on a permanent cell line derived from a reptile (Z1), with the advantages of low population doubling time. Considering the approach of replacing cell-based culture methods instead of egg-based, it may be possible to use this cell line extensively in the future by completing the preliminary studies of this research.