It is of interest both clinically and immunogically to investigate the first appearance of antibody in foetus during the pregnant period. From this view point 65 samples of maternal blood, 8 samples of foetal cord blood, 3 samples of heart blood and the emulsions of the various organs such as liver (32 samples), spleen (8 samples), muscles (7 samples) and whole embryo tissues except liver (36 samples) which had been collected in each pregnant month were tested by neutralization test against Japanese encephalitis virus with the following results.
1) The titer of neutralizing antibody of umbrical cord blood was generally a little higher than those of venal blood specimen of the mother. The heart blood of 7-9 month old foetus showed approximately the same or a little lower titer than those.
2) The titer of neutralizing antibody of the liver emulsion of embryo aged two months was found lower than those of maternal blood. On the third month of pregnancy a certain percentages of the embryonic samples began to show higher titer. After the fourth month almost all the embryonic samples demonstrated high neutralizing agent.
3) As for the embryonic tissues except spleens, muscles and liver, the emulsion of them failed to show any relation with maternal blood specimen as observed in the case of liver emulsion mentioned above.
To discuss the specificity of the neutralizing substance mentioned so far, maternal blood specimen (10 samples), embryonic liver emulsion (5 samples), emulsion of whole embryonic tissues except liver (1 samples) and umbrical cord blood (4 samples) were examined by the neutralization test against Japanese encephalitis, St. Louis encephalitis and western equine encephalitis viruses.
Except a few exceptions (3 samples of liver emulsion and one sample of the whole tissue emulsion except liver), all the rest of the tested samples were negative against St. Louis encephalitis virus. The four specimens positive aginat St. Louis encephalitis virus were further tested against Japanese encephalitis virus. They resulted in positive of more than 1, 000 neutralization index. Two of those positive samples were also positive against western equine encephalitis virus. Before going to conclusion it should be kept in mind that there has been no confirmed information on the existence of St. Louis encephalitis in Japan. The positive neuttalization test may be due to the cross reaction between both Japanese and St. Louis encephalitis viruses though it is too much to admit all the neutralizing substance as specific.
One sample of maternal blood, one sample of cord blood and two liver emulsions were positive against western equine encephalitis, but all the rest of the specimens tested were negative. The four western equine encephalitis positive samples were also positive against Japanese encephalitis virus with over 1, 000 neutralization index. Of the four positive samples, two were also positive against St. Louis encephalitis virus. From foregoing results it may be concluded that some non-specific virulicidal substance might exist in the tested samples both organ emulsion and blood and that the neutralizing antibody against Japanese encephalitis virus could be detected in organ emusions of foetus aged four month higher than those in its mother's blood.

抄録全体を表示

The attempt was made to investigate experimentally the immunological relationship between mother and her new born. Three female rats were immunized with two or three doses seven days apart and sometimes with booster dose with chorioallantoic fluid infected with Influenza A′ (FM1). During the period of immunization the immunized mother rats bare babies sixtimes and another one normal female as control bare them twice during the period of experiment. When the mother bare her babies the blood was taken from her and her babies for hemagglutination inhibition test. Each baby gave too small amount of the blood to carry out the test. Consequently the blood was pooled from all babies. At the same time the liver emulsion and whole baby emulsion except liver were made with saline water for the test. All test samples were inactivated at 56°C for 30 minuts to destroy R. D. F.. If they showed positive inhibition they were treated with Vibrio cholerae filtrate (Vf) prepared according to Dr. Tyrrell. to exclude non-specific inhibiting substance.
The results were obtained as follows.
1) It was recognized that there was no non-specific inhibiting substance excluded by Vf in mother's, new born's sera and new barn's liver emulsions but emulsions of whole baby except liver contained the non-specific inhibiting substance which was proven completely excluded by Vf.
2) The high titer of inhibiting antibody was found in the mother rat after immunization and it was assumed that the antibody might pass through the placenta into the foetus in the titer of one fourth or less than in the mother.
3) It was not able to detect the specific inhibiting antibody in the liver emulsions and the emulsions of whole body except liver of new horns from the immunized mother.

抄録全体を表示

In the previous paper the isolation of SG strain of Izumi-fever virus from feces of a sporadic case was reported.
The present report describes the preparative methods of the Izumi-fever vaccine and the relation between degree of immunity of mice following vaccination and the titer of neutralizing antibodies in the serum.
In this experiment formalinized vaccine, Merzonin vaccine and ultraviolet-irradiated vaccine were prepared.
The brain of a mouse infected with SG strain was ground in a mortar under sterile conditions. The emulsion thus obtained was diluted by ten volumes of phosphatebuffered saline of pH 7.0. After the diluted emulsion was centrifuged at 3, 000 r.p.m. for 15 minutes, the supernatant was used for the starting material of the following vaccine.
The supernatant fluid was added with formalin in 0.1 and 1.0 per cents, or with Merzonin in 0.01 and 0.1 per cents, respectively. A portion wasi ncubated at 37°C and the other portion was kept in a refrigerator of 4°C, each for 5 days. After the incubation 1 per cent formalinized vaccine was dialysed against distilled water until the vaccine indicated negative Fehling's reaction. To test the infectivity of the each portion, samples were injected daily for 5 days into the mouse brain. The complete inactivation was observed only in 1 per cent formalinized vaccine which was incubated for 5 days, whereas it was not found in other vaccines in the same periode of days.
Ultraviolet-irradiated vaccine was prepared in the following manner. About 2.0ml of the vaccine material were placed in a Petri dish in a distance of 9cm from the ultraviolet lamp. The virus solution was irradiated for 5 minutes and then tested for the infectivity by injecting 0.03ml intracerebrally into mice. Consequently it showed no infectivity after exposure under the condition mentioned above.
The immunizing potency of the formalinized and ultraviolet-irradiated vaccine were determined in the following way. Each of test mice were injected 0.5ml of the vaccines intraperitoneally every other day for 2 doses. The challenge virus was injected intracerebrally or intraperitoneally into mice 2 weeks after the final immunizing administration.
In the experiments vaccinated mice showed about 100 to 1000 times of resistance being compared with non-vaccinated controls.
Neutralization tests were done with pooled sera obtained from mice by heart pucture or cutting the axiillary artery 3 to 14 days after vaccination. The broth was used instead of serum in the control test. These sera or broth were mixed with virus solution diluted 10 times serially and injected intracerebrally into mice, and the inoculated mice were observed for 14 days. Consequently the sera collected from mice 3 days after vaccination showed already a little neutralizing power. Then the antibodies were increasing daily, and finally showed a titer as high as 2.6 in neutralizing logarithm 14 days after vaccination.

抄録全体を表示

During the past 6 years 6 strains of hepatotropic virus of mice have been described. Some of them appear to be related to each other serologically.
The present mouse hepatitis virus (Buescher's EHF-120) was encountered during attempts to establish the agents of hemorrhagic fever in mice by serial blind passage of viscera.
The purpose of this communication is to give some account of the disease produced in mice by this virus and to describe its general properties.
Acute hepatitis was regularly reproducible in mice by the intraperitoneal injection of liver suspensions from dead or moribund mice. Infected mice showed a ruffled coat, “hunched” posture, and fine tremors before death. The incubation period was usually about 30 hours and the desth was occured between 2nd and 3rd day. The urine was staining some times the coat in the perineal region, but there was no external indication of jaundice.
On post-mortem examination the most striking abnormality was found in the liver. Liver was pale yellow and mottled with petechial hemorrhages. In other organs there was no obvious lesion.
The distribution of the virus in several viscera after intraperitoneal injection was determined and the high concentration was proved in liver and brain. The virus was also found in the spleen, kidney, lung, , intestine and blood of the infected mice at the death or moribund stage.
Other inoculation procedures were also examined. The mice were infected by intracerebral, intranasal, subcutaneous, intravenous, per os, and food pad inoculation. Gross pathological changes in the liver were seen in all dead mice, irrespective of the route of inoculation, suggesting a hepatotropic character of this virus.
The virus survies heating at 60°C for 30 minutes and exposure to ultraviolet-irradiation at the distance of 9cm from the lamp for 5 minutes. The activity of the infected liver in 50 per cent glycerol was retained on storage in the refrigerator for intervals up to 2 months. The filtrate of the liver suspension through Seitz EK filter was also infectious.
Attempts were made to infect rats, guinea-pigs, hamster, and rabbits by intraperitoneal or intravenous inoculation of infected mouse liver extract, but no symptoms or lesions were produced in these species.
The chorioallantois of 9 to 13 day old chick embryos was inoculated with infected mouse liver. After 48 to 72 hours' incubation at 36°C discrete white foci were noticed on these membranes at least at the beginning of this experiment. On continued passage, the numder of foci produced decreased progressively. Although the virus was detectable in the chickembryo liver and on the membranes by mice inoculation in the 1st to 4th passge, it became impossible afterwards.

抄録全体を表示

The attempt was made to follow up how the antibodies, mainly neutralizing antibody and partly hemagglutination inhibiting antibody do pass from the mother onto her new born rats in the experiments, (1) active immunization with living virus, (2) passive immunization with homologous immune rat serum during the later half of pregnancy as well as after the birth, (3) cross lactation test between the immunized mother rat and her new born and the normal mother rat and her new born (4) oral adminsistration with homologous immune rat serum in the new born from the normal mother rat. The results were obtained as follows:
1) Neutralizing and hemagglutination inhibiting antibodies were detected in sera both from the pregnant rats immunized actively and passively respectively.
2) The titer of neutralizing antibody in the new born which might be transfered through the placenta from the immunized mother is less than those in the mother rat.
3) when the new born from the immunized mother are lactated from the norma 1 mother rat their neutralizing antibody will disappear gfadually in 40 to 50 days after the birth,
4) Both neutralizing and hemagglutination inhibiting antibodies are transfered through lactation from the immunized mother rats onto the new born from the normal rat. Their titers are the same or nearly the same to those of their mothers. The antibodies in the now born which was transfered passively through lactation would disappear parallel to those of the passively immunized mother or after the weaning from the actively immunized mother which are still positve in antibodies.
5) No significantly positive reaults were obtained to find both neutralizing and hemagglutination inhibiting antibodies in the sera of the new born following oral administration of homologous immune rat serum. The results are, however, suggested that the antibodies might pass through the oral route onto the new born rats.

抄録全体を表示

The author examined the polarographic effect of proriferation of influenza virus on catalytic protein waves exhibited by the chorioallantoic fluid of developing chick embryo and obtained the fllowing results.
Catalytic protein waves of the chorioallantoic fluid discerned in various conditions can be classified into five types. They were designated as A, B, C, D and E waves respectively. Generally speaking, in normal eggs, the waves appeared in the order of A waves to E in sequence as the incubation days prgressed. In the inoculated eggs with the virus, the process was delayed. with wave height, in the normal eggs, it rose until the sixteenth day, as the incubation days progressed. While in the inoculated eggs the rise was not distinct, and the significant difference was recognized between the two.
A, B and C waves presented characteristic single catalytic waves and was analogous to catalytic cystine waves. E wave was observed as double catalytic waves and was shown to have the similar nature as serum protein waves. A possibility that the above facts can be utilized to know the existence of multiplication of viruses in the developing chick embryo, whether they are already known or quite new, was discussed.

抄録全体を表示

A new form of virus newly-isolated from mice and considered to belong to the MNI group was treated in present report and several characteristics were described. Although it can be regarded to have characters highly similar with those of the influenza viruses, its hemagglutinating activity is subject to change, being especially conspicuous in its thermofragility. We, therefore, consider those characters to be helpful in analysing the inter-relationship between this form of virus and the influenza viruses.

抄録全体を表示

10⁶ EID₅₀ of the standard passage virus of influenza, PR 8, were inoculated into 11-days developing eggs. The production of the incomplete virus was observed from 8 to 48 hours after inoculation with respect to the EID₅₀/HA ratio as the indicator of the presence of incomplete particles.
1. In chorioallantoic fluid, the EID₅₀/HA ratio increases rapidly in the beginnings of the viral growth and then slowly. Its maximum value is around 10^6.6 (48 hours after inoculation).
2. In chorioallantoic membranes, EID₅₀/HA ratio increases slowly to 14 hours after inoculation. Then it takes constant value, 10^3-4. Always its value is lower than the value in the case of the chorioallantoic fluid from the same egg.
3. When the inoculum size of 10⁶ EID₅₀, mid poind of the von Magnus's standard passage and undiluted passage, the incomplete form of the virus is found mainly in infected chorioallantoic membranes and there is no incomplete particle in chroioallantoic fluid later than 14 hours after inoculation.
4. These results were confirmed by three different extraction methods but the findings was the same.

抄録全体を表示

The causative agent of Q fever, Coxiella burnetii, was reported to be cultivated by Maitland's method (Burnet and Cox), in yolk sac of developing chick embryo (Cox), and by Zinsser's agar-slant tissue culture (Takemori and Kitaoka). Herewith an attempt was made to determine whether or not the Zinsser's agar-slant tissue culture was avialable for screening any antibiotic and chemical effect upon the inhibition of growth of Coxiella burnetii. Prior to using this culture method for this purpose, it should be investigated more in detail concerning the tissue to be cultivated, daily occurence of the tissue culture and the resistance of the agent in the culture. The results were obtained as follows.
1. Coxiella burnetii. can be cultivated by the Zinsser's agar-slant tissue culture by using tissues of human-, chick-, guinea-pig-, rat- and mouse- embryos, testicle, kidney and spleen of adult guinea-pigs, rat rhodamine sarcoma and mouse furctose sarcoma. In general, the tissues of human-, guinea-pig- and chick embryos gave better growth of the agent than the other tissues mentioned above.
2. The agent could not been recognized under microscope in 1-2 days, but appeared in 3 days and showed a maximum growth in 4-5 days after its cultivation by using chick embryo tissue.
Such a maximum growth was observed for 20 days though the agent decreased a little in number.
3. Aa for ID₅₀ of infected chick embryo tissue, it may be computed by the passage method with each ten fold dilution of each daily infected tissue from 10^-1 to 10^-8, that 10^4.5, 10^5.5 and 10^5.2 of ID₅₀ were calculated immediately, 1 and 2 days respectively after the cultivation. During this period the microscopical findings were proven to be Coxiella negative. But ID₅₀ of infected tissue was estimated 10^7.5 on the 8th day after its cultivation, when numberless coxiellae were found under microscope.
4. Coxiella was able to be cultivated by the passage after it was preserved at 37°C. for 12 months.
5. Coxiella grew in Zinsser's agar-slant tissue culture by using lace albumine hydrolysate instead of horse serum, when the former seemed to cause a little less growth than the latter.

抄録全体を表示

The burst frequencies and burst sizes of a polylysogenic Escherichia coli, strain A34, were described here.
The burst frequency of β phage was about 2×10^-4 and that for γ phage was about 5×10^-5. The mean burst size of β was about 200, whereas that of γ was only few. These differences will indicate that the prophages β and γ were linked to the chromosomes of the host lysogenic bacteria at the different loci each other.
The β phage yields in individual bursts were ranged between 4 and 1552, and it was found that these burst sizes were distributed in a type of logarithmic normal distribution suggesting that the phage multiplication in the lysogenic bacterial cell was carried at a exponential rate in vegetative phase.

抄録全体を表示

Quantitative analysis on the interactions between prophage and superinfecting phages has offered a possible way to approach to the problem of prophage conditions in lysogenic cells and has brought many important knowledges.
The present paper deals with the prophage substitution phenomenon in a temperate phageinfected lysogenic bacteria. Growing lysogenic cells of BI (δ) strain were superinfected with another temperate phage, beta strain, which is serologically unrelated to the carried phage, delta. When the superinfection was carried with a high multiplicity of infection (more than 10 beta particles per bacterium) it was found that about 99.7 per cent of them were killed and only about 0.1 per cent can form survival colonies. The phage produciable fraction of them were about 0.1 per cent for beta and only about 10^-4 of the beta-infected BI (δ) cells can produce delta phage.
The survival colonies were, then, tested for their lysogenicity and it was discovered that in about 20-30 per cent of the survival colonies prophage substitution by the infecting beta phage occurred. No double lysogenic colonies which produce both phage types, beta and delta, however, were found in 351 colonies tested. This will suggest that beta and delta are mutually exclusive in lysogenization process.
According to these results some discussions were made around the intracellular prophage conditions.

抄録全体を表示

The possibility of selective spread through pyramidal tract of polio virus was studied with mice inoculated intracerebrally with Lansing strain. The inoculation was made mainly into the right cerebral hemisphere.
Results obtained indicated that the number of mice showing paralysis only right leg (identical side for the inoculation) was about equal to that showing paralysis only on the left leg (opposite side for the inoculation) either in the group inoculated with virus of 3000×LD₅₀ or 30×LD₅₀.
No coclusive evidence, therefore, was obtained as to the reality of the “pyramidal tract spread” theory of polio virus.

抄録全体を表示

Thin sections of tissue cultured cells, mainly fibroblasts and epithelia of irises from chick embryos were studied with the electron microscope.
It was found that the mitochondria with their cristae mitochondriales were present in the cells examined.
The technique how to obtain the ultrathin sections of tissue cultured cells was explained and discussed: many difficulties were encounterd in the removal of cultured tissues from the glass substrates and in the exclusive collection of new grown tissues.

抄録全体を表示

The morphological changes of Yoshida sarcoma cells infected with ectromelia virus were studied with the electron microscope using the thin sections and the phase contrast microscope.
Phase contrast microscopic observations: The inclusion bodies were clearly found in the cytoplasm at 72 hours after inoculation. They were frequently revealed as an accumulation of elementary bodies and varied in size. The serious necrotic changes were seen in the cytoplasm at the later stage, and the diffuse distribution of elementary bodies was observed in them.
Electron microscopic observations: The inclusion bodies and matrix regions were found in the infected cytoplasm as they were in the case of other tissues. The inclusion bodies were sharply outlined from the cytoplasm. The elementary bodies embedded within the inclusions showed polymorphological appearances and their density was less than that in mature particles. Though empty circles were found in matrix region, it was not proved that the relationship was present between these bodies and mature virus particles.

抄録全体を表示