Iscom of viral envelope proteins protects against Aujeszky's disease.

An immunostimulating complex (iscom) containing the envelope proteins of pseudorabies virus (PRV) was prepared and its efficacy was evaluated in two experiments on sheep. In the first experiment, sheep were intramuscularly (i.m.) or intradermally (i.d.) vaccinated with PRV iscom doses varying between 1 and 81 micrograms. The vaccination was repeated on Day 21 and the animals were exposed to challenge infection by subcutaneous inoculation of 1000 TCID50 of the virulent Phylaxia strain on Day 35 after first vaccination. In the second experiment, sheep were i.m. vaccinated with single doses of iscom varying between 1 and 27 micrograms and challenge-infected on Day 14. It was found that: (1) the i.d. administration of PRV iscom has no advantage over i.m. administration (2); a single dose of greater than or equal to 3 micrograms of PRV iscom provided protection against the disease. In immunoblots, viral proteins of molecular masses 120, 109, 55, 53 and 32 kDa were detected with the sera obtained from iscom-vaccinated and subsequently challenge-infected sheep, but not with sera from sheep which were iscom-vaccinated only. The above findings indicated that: (1) by using iscom technology, potent subunit vaccines can be prepared to prevent Aujeszky's disease; (2) the selective incorporation of viral envelope proteins into iscoms gives the opportunity to discriminate between iscom-vaccinated and naturally infected animals.

Relationship between maternal and infant iron stores: 1. Full term infants.

Serum ferritin, serum iron and total iron binding capacity were determined in 218 pregnant women at term and in the cord blood of their normal term infants. Both the mean weight (3210 g) and serum ferritin level (geometric mean 81 micrograms/l) of the neonates of iron deficient mothers were significantly lower than those of mothers with "normal" iron stores (weight 3390 g; cord ferritin level 115 micrograms/l). A weakly significant correlation was found between the logarithm of the maternal and neonatal serum ferritin concentration (r = 0.15, p less than 0.05) and the maternal log serum ferritin and the newborn's weight (r = 0.15, p less than 0.05). The weak correlations were supported by the differences between the values of cord samples from babies of iron deficient mothers and those whose mothers had "normal" iron values. Adequate iron supplementation during the early period of pregnancy is suggested.

[Requirements of rabbit-adapted swine fever vaccine]. / Anforderungen an die kaninchenadaptierte Schweinepestvakzine.

Studies were conducted into the demands made on both harmlessness and effectiveness of SUVAC, a swine fever vaccine prepared from strain "C", a rabbit-adapted Chinese virus strain. The following findings were obtained: --The vaccine strain was attenuated to an extent by which it could be used without serum. --The vaccine was harmless even with immunodepressor action. Its immunogenicity was good, and live weight growth of the animals was not impaired. --The vaccine was harmless to the foetuses. --Very little virus was excreted by immunised pigs. --Vaccine attenuation was of high stability, and virulence was not even increased after six passages in pigs. --Between 50 and 100 immunising units were contained in one vaccine dose, and piglets immunised at the age of six weeks were protected after three months against an experimental infectino which was fatal to susceptible pigs. --Virus inoculated into PK 15-cell line proved negative in the first passage in response to immunofluorescence testing.