Quantitative Studies on the Infectivity of the Virus of Herpes Simplex for the Chorioallantoic Membrane of the Chick Embryo, Together with Observations on the Inactivation of the Virus by Its Specific Antiserum

[摘要] 1. 1. A strain of herpes simplex virus readily produced macroscopic foci of lesion on the chorio-allantois of developing chick embryos when infective rabbit or mouse brain material was inoculated into fertile eggs of the proper age. In one series of transfers, initiated with rabbit brain virus, 42 egg to egg passages were obtained with foci in each. The gross and microscopic development of the lesions are described.2. 2. By inoculation of a series of membranes with equal amounts of suitable dilutions of egg-membrane virus and determination of the averages of the counts of the individual membrane-foci for each dilution, it was possible to titrate the quantity of virus present.3. 3. It was found that for this strain the inoculation of an amount of virus sufficient to produce one or a very few foci on the chorioallantois would also initiate fatal herpetic encephalitis in mice after intracerebral inoculation.4. 4. The rate of increase of the virus in the chorio-allantois following inoculation into 12-day eggs was examined. During the first two days of infection the concentration of virus rose markedly, then increased more slowly to reach a maximum between the end of the third and fourth days; after which the concentration diminished, at first abruptly then more gradually.5. 5. Egg-membrane virus was found to maintain infectivity better when frozen at −10°C. than when placed in 50 per cent glycerol-Tyrode's solution at 4°C. Suspensions of egg-membrane virus in Tyrode's solution retained their infectivity for at least two weeks at 4°C.6. 6. For three samples of hyperimmune rabbit sera examined, it was determined that small amounts of antiserum could neutralize several thousand focus-initiating virus-units. Similar values for these sera were obtained by the parallel inoculation of mixtures of the same antiserum + virus intracerebrally into mice. Neutralization was equally effective whether the mixtures were injected immediately or ten minutes after preparation or were held for an hour at 25°C. before testing. Attempts to demonstrate reactivation by dilution of inactive mixtures were unsuccessful.7. 7. In experiments designed to learn the rate of fixation of the virus to cells of the chorio-allantois it was found that within 5 minutes of contact, from 4 to 8 per cent of the viral inoculum might be fixed and produce lesions on the chorio-allantois despite the later presence of antiserum. By six hours as much as 50 per cent of the virus was fixed while by 18 hours all of the virus was so situated as to be insusceptible to subsequent antibody administration. Immune serum reaching the chorio-allantois 5 minutes previous to or simultaneously with the virus, effectively prevented the formation of any lesions.

[学科分类] 生物科学（综合）