| In this study, 6 healthy horses and 4 donkeys were experimelltally inoculatedwith donkey leukocyte adaPted vaccine strain (DLA),fetal donkey dermal-adaPtedvaccine strain (FDD), PD9 and PD9L2 derived from the FDD infectious molecularclone PFD3, respectively. Then the proviral DNA was regularly monitored in theperipheral blood monocytes (PBMC) from the inoculated animals by nested-PCR. Toclarify Whether the infectious clone derived viruses has the same immwhty as FDD,the 4 donkeys inoculated with PD9 and PD9L2 were challenged with donkey adaPtedequine infectious anemia virus (DA-EIAV), a wild-type pathogenic Strain. Accordingto analysis and comparison of the special sites in the gp90 of env region that havedistinct differences between the Chinese wild-type virulent strain (LN-EIAV andDA-EIAV) and the vaccine strain (DLV and FDD), 4 Primers were designed and usedby PCR to detect the proviral DNA in PBMC of the challenged edmals.Through specific amPlification of the LTR of Proviral DNA by the neSted-PCR,the EIAV specific proviral DNA was detected in the PBMCs of both DLV andinfectious clone derived viruses inoculated animals in l5 days post inoculation. wnleLTR was not detected for a short time 3 months after inoculation in some edmals, inthe rest time, the results of amPlifying were always positive in most bomals Unil theday 390 after inOculation, the LTR was amplified in the peripheral blood monocytes ofmost animals. The results first showed there was provira DNA integration in ChineseEIAV vaccine strain and its infectious clone derived viruses vaccinated animals.The rectal temperatUre of the aIilmals D1 and D2 (inoculated with PD9) showedthat an instananeous rising twO weeks after challenge. ln coIhaSt, there were no anyclinical signs observed in anAnals D3 and D4 (inoculated with PD9L2) during all themonitoring time. The control animal developed tyPically infectious anemia and died l7days after challenge. The results of the agar gel irnmunodiffosion assay showed thatantibodies against P26 in Dl and D2 were all negative wti1 6 months aller thechallenge with the DA-EIAV On the contrmp, antibodies against P26 changed to bepositive in one month after the inoculation, as D3 lasted for 3 months and t'Um positiveonce again after the challenge, D4 kept being positive all the tdries before and after thechallenge. All the 4 donkeys were alive healthely after challenging with DA-EIAV ti1lthe end of this experiment, and they are still under monitoring.Infectious molecular clone PFD3 derived virus PD9 and PD9L2 have inducedpartial immune protection from challenge. There were a large number of mutations inthe env region of proviral DNA in the PBMCs through analysis of amplified sequences,and their coding amino acids aPpeared regular mutations as the time went by At thepoint that can distinguish the Chinese wild-tyPe vAnlent strain (LN-EIAV andDA-EIAV) and the vaccine strain (DLV and FDD), different Anmals present differentstams after the challenge, but there is a comxnon ttend that the tested sequenceschanged from the comPlete wild-type immediately after challenge to vaccine-type ortheir common traits of challenge time. The wild-type sequence of the proviral DNAwas not eliminated from the PBMCs of all anima1s testCd at the end of this study. Nomatter What, all the vaccinated animals resisted the lethal-dose challenge. Though theproviral DNA was detected in some time, all the animals aPpeared clinically healthy ina majority of time.The study firstly revealed that the proviral DNA can be detected in the periphera1blood monocytes from axilmals inoculated with the Chinese attenuaed equineinfectious anemia virus (DLA and FDD )vaccine and the infectious nlolecular clonederived viruses (PD9 and PD9L2), and showed the sequence of the proviral DNA fromthe donkeys after challeng with the DA-EIAV All these discoveries would no doubtbe helpful to the clarification of the molecular immune prote... |
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