RESUMO
AIM: This study aims to determine the effect of the stationary rawx, roller, and the suspension cell culture systems on the total virus yield infectivity and antigenicity. MATERIALS AND METHODS: Three serotypes of foot and mouth disease virus (FMDV) (serotype A, O and SAT-2) were inoculated separately into baby hamster kidney-21 cell line in rawx, roller, and suspension cultivation systems using multiplicity of infection (1:100). Samples were taken from the total virus yield from each system at 15, 18, 21, and 24 h post-inoculation. Testing the total virus yield infectivity through virus titration and antigenicity through estimation of complement fixing titer and 146S content and evaluation of the potency of the vaccine prepared from the different cultivation systems were done. RESULTS: The results showed that the FMDV titer of serotype A, O, and SAT-2 obtained from the roller cultivation system showed the highest level followed by suspension cultivation system then the rawx cultivation system. The FMDV titer showed its highest level at 21 h post-inoculation in all the cultivation systems and then decline at 24 h post-inoculation. The antigenicity reached its highest value content at 18 h post-inoculation either by complement fixation test or by quantifying the 146S intact virion. Montanide ISA 206 oil inactivated trivalent vaccines were prepared from the tested serotypes (A Iran O5. O Panasia and SAT-2/EGY/2012) harvested at 18 h post-inoculation from the 3 culture systems. The results of tracing the antibody response showed that the mean antibody response from the roller cultivation system start its protective antibody titer earlier at 2 weeks post-vaccination (WPV) than the vaccine prepared from the other two cultivation system and the immune protection period lasts longer for 36 WPV for the roller cultivation system vaccine than the other two cultivation systems. CONCLUSION: The best cultivation system used for the production of FMD vaccine regarding its highest infectivity and antigenicity is the roller system.
RESUMO
AIM: A comparison study was conducted to explore the best internationally available adjuvant that could be used in production of a highly potent foot and mouth disease (FMD) vaccine, that could stimulate a strong immune response and possibly give greater protection against FMD. MATERIALS AND METHODS: Four experimental batches of trivalent FMD vaccine were prepared with different available oil adjuvants which included Montanide ISA 201, 206, 61 and 50. RESULTS: The results indicated that vaccines emulsified using Montanide ISA 201 and Montanide ISA 206 adjuvants elicited a protective humoral immune response from the 2(nd) week postvaccination (WPV) as for ISA 201 with serum neutralization test (SNT) and enzyme-linked immune sorbent assay (ELISA) antibody titers of 1.62±0.047(a) and 1.8±0.049(a), 1.59±0.076(a) and 1.836±0.077(a), and 1.71±0.06(b) and 1.96±0.074(b) for serotypes O, A, SAT2, respectively, and for ISA 206 at SNT and ELISA antibody titers of 1.5±0.082(a) and 1.84±0.084(a), 1.56±0.037(a) and 1.818±0.052(a), and 1.5±0.106(a,b) and 1.81±0.104(a,b) for FMD virus serotypes O, A and SAT2, respectively. For ISA 61 and ISA 50, the protective antibody titer appeared in the 3(rd) WPV. In the ISA 61 FMD vaccine, SNT and ELISA titer were 1.59±0.076(a) and 1.9±0.094(a), 1.53±0.056(a) and 1.83±0.070(a), and 1.5±0.082(a) and 1.84±0.094(a) for serotypes O, A and SAT2, respectively, and in the case of ISA 50 FMD vaccine, the SNT, and ELISA titer were recorded for serotypes O, A and SAT2 respectively, 1.59±0.037(a) and 1.8±0.030(a), 1.68±0.056(a,b) and 1.916±0.065(a,b), and 1.65±0.082(a) and 1.9±0.09(a). On estimating the cellular immune response, the highest delta optical density levels for ISA 201 (0.395-0.460) and ISA 206 (0.375-0.428) were observed on 14 and 21 days post vaccination (DPV) respectively, while the highest levels of lymphoproliferation for ISA 61 (0.375-0.455) and ISA 50 (0.411-0.430) were on 21 and 28 DPV, respectively. CONCLUSION: The duration of immunity from Montanide ISA oils (201, 206, 61 and 50) FMD vaccines is a long-lived immunity which ranged between 32 and 38 weeks post vaccination but the Montanide ISA 201 FMD vaccine is superior to the others in the rapid cellular immune response of the vaccinated animals which showed its highest level within 14 days post vaccination.