Hot cholera (HQ virulent virus such as AL]) strain and field isoiat can It detr1 in vitro by the End tt which was fIrstly rejnt by Kuiriagai et al. Sortie tissue culture-ateiuael HC virus which shows the End negative such as (WE-strain can be deznonstrad by the mafestce (IF) est (Shixny et al.), and 1DM strain by the friD test (Satoetai).
However, There is still no in vitro tst for the 1apinid HC virus (LPC stain) which has Inn widely applied for HC control ik Taiwan for moie than 15 years, lltefore, thestwiies onthelapiniJvacciitandit assayhavedevelodosilyintheg incculaton tt that wasti much money and time for it peifonnarte.
With the in entionofdevelopinganinvitornethcdfor&dettionandtitationof lardniad HC virus, the piesent study has ken rerfonnoi. The result axe surnrnarl as follows:
1 .Lapfrii HC virus could not It dewed by the END tt. Although tie virus was treatl by jxolonging the cultured period (challenged with Newcastle disease virus (NDV) on the 6th or 8th thy) or jriiously passing through smt tticle S1) cell cultures, theist 3rd and 5th passage virus showeinegative result mtheE1D tstl]t iF tt challenged with Westn oqune encephalomyelitis (WEE) virus, performed with the procedures mentioned a&ne also showed the 1 F phenomenon negative. That iran the lapnii HC virus od not It detecel by the F tt.
2.Aft the challenge of NDV the ND V-HA titers in ST cell paeviously in fecel with the lapanised HC virus were much lowers than that in ALT) virulent virus infected grou and the same as the that of the cell control group without HC virus treatment, The NOV-HA titers of the two groupt it. the lapiniwd virus group and the cell control group increased when the amount of NOV incculation and the age of ST cell cultures enlarged, On the contrary, the GPE-HC virus group showed a marked
Snnnnary growth interference if NOV. on which no aTD-CPE ard increased NOV-HA titer Were found, fuiiltmore, the monok cultures appeared much better compared with the cell control group.
3.Tt was found that the growth intfferta phenomenon oxuntl HC virus and it homologous virus on ST cell culture, lit GPE-HC virus that was Cultntl in the 1apinidHCvirus thfozJSTcellcouldnotbedeaJbythe IFestchallenged with WEE virus, that is GPE-HC virus was interfered ST. cell. Tie growth interference phenomenon of its homologues virus by HC virus could It applied for the detection and titration of lapiniad HC virus. This was esbbshrnent of the sndard prxedure of this new method is still underway.
4.Lapini1 HC virus could It deectd by means of the fluorcent anti&dy-cell culture est (FA(Ufl, and forrrJ so-called lacpi&on the PK- 15 monolayer culture just h] ALD virulent vh-us did, ‘tnt the plaque horn bpiniJ virus was much smaller than that from ALD virulent vinis of the same hours ulture? The fluccence of lapiniad HC virus was oberved only in the cytoplasm of infect! P%15 cell but not in the nucleus.
5. It was much moie sensitive In detng the lapAnbd HC virus by & FA(Xfl’ witi the virus was previously cultured in ST cell for 4t5 days than directly inctulani the virus on PK-15 monolayer, andits virus tins was thesarneas thatof pEg inoculation tn This rnethcd was provisionally called, wo-stp FAQJl7ffont Both methods of omo Virus Interfexerice?and wo Se? FA(XThnentioned abDveaseworthytotheapplialforthevirus nnonandntranonm&assayof the lapiniJ tiC v&xlne. And the methods can save much extnse and aihance the prcdxncsi and application of the lapinid tiC vathit