Improving genetic testing pathways for transthyretin amyloidosis in France: challenges and strategies.

Transthyretin amyloidosis (ATTR) is a severe and rare disease characterized by the progressive deposition of misfolded transthyretin proteins, causing irreversible organ damage. Transthyretin amyloidosis can present as a hereditary ATTR or acquired wild-type ATTR form. Genetic testing is critical for determining a hereditary predisposition and subsequently initiating appropriate family screening.

Selection of vaccine strains of foot and mouth disease virus for use in southern Africa.

In the countries of Southern Africa, types SAT 1, SAT 2 and SAT 3 (SAT: Southern African Territories) of foot and mouth disease (FMD) virus are the most widely represented, especially the SAT 2 virus. Since 1982, examinations have been conducted on 139 isolates of these virus types. Other viruses, types O and A, have been detected in the north of this area.

Vaccination against pseudorabies with glycoprotein gI+ or glycoprotein gI- vaccine.

Subunit pseudorabies vaccines that contained only purified glycoproteins of either of 2 strains of pseudorabies virus (PRV) were prepared and subsequently tested for safety and efficacy. The strains of virus used for vaccine production differed in at least 2 properties. One strain (Kojnok) was virulent for pigs and was believed to code for the entire complement of viral glycoproteins.

Development of an ELISA to differentiate between animals either vaccinated with or infected by Aujeszky's disease virus.

The use of two monoclonal antibodies specific for glycoproteins GI and GIII of the pseudorabies virus led to the development of a competitive ELISA which made it possible to differentiate animals infected with pseudorabies virus from animals vaccinated with the strains of the virus Bartha, NAI4 or Norden. A postvaccinal serological response could be detected from three to four weeks after vaccination. After the virulent challenge of these vaccinated pigs an infectious serological response became apparent two weeks after the challenge.

The potency testing of pseudorabies vaccines in pigs. A proposal for a quantitative criterion and a minimum requirement.

A criterion for the potency testing of pseudorabies vaccine based on the difference between the mean weight gain during the seven days after pathogenic challenge of vaccinated or control piglets is proposed. This criterion, termed delta G7, has been studied as a function of initial weight variation of the animals, different challenge strains and the period between challenge and the end of the test. The statistical analysis of results optimizes the experimental parameters and gives rise to a quantitative test which discriminates between vaccinates and controls and substantiates a proposal for a minimum vaccine potency requirement.

Identification of the pseudorabies virus glycoprotein gp50 as a major target of neutralizing antibodies.

A total of 108 monoclonal antibodies specific for pseudorabies virus (PRV) were isolated in a cellular fusion, using spleen cells from mice which had been immunized with a live strain (Kojnok strain). Twelve of them neutralized the Kojnok strain in vitro in the absence of complement, as well as 28 virulent strains of various geographical origin and isolated from various animal species. All of the 12 clones were specific for glycoprotein gp50.

Biochemical study of the Feline Herpesvirus 1. Identification of glycoproteins by affinity.

Feline Viral Rhinotracheitis herpesvirus (Feline Herpesvirus 1; FHV-1) was purified by rate zonal isopycnic centrifugation. Viral nucleocapsids were isolated from the nuclei and purified. Analysis of the purified and radiolabelled viral polypeptides and glycoproteins by gradient SDS polyacrylamide gel electrophoresis revealed that 23 viral proteins and 6 glycoproteins were present in the whole virus particle.

Bilan de deux années de production de vaccin de la fièvre aphteuse au Botswana vaccine Institute.

This paper describes the setting up of an emergency foot and mouth disease vaccine production Unit in Botswana. No major problems were experienced in producing effective vaccines against SAT 1, SAT 2 and SAT 3 types of FMD virus. The vaccines which were produced were tested in cattle, and in general the bovine Potency values were high.

[Particularities of the morphogenesis of the rabies virus and of its morphology observed during routine culture controls through the electron microscope].

Whilst practising routine controls with an electron microscope on NIL 2 cell cultures infected by the rabies virus, the occasion arose to reveal certain features of the morphogenesis of this virus and the particular action of glutaraldehyde which alters the aspect of the rabies virus. During the cultures, we witnessed, in succession, the production of morphologically normal virions, then progressively degraded virions whilst the cells recover and develop towards a chronic infection state. Glutaraldehyde treatment of the suspensions proved to be of great interest for electron microscopy observation.

Thermostability of the rabies virion. Optical density measurement technique applications.

The thermal degradation of rabies virus was determined by the variation in optical density at 260 nm during temperature rise. This variation, linked to denaturation of RNA, was seen by an irreversible sigmoidal curve. Analysis of the state of the virion by ultracentrifugation did not show any alteration in sedimentation.

[Feline rhinotracheitis: a purified inactive vaccine and an experimental model].

The medical prophylaxis of feline rhinotracheitis is presently carried out varying success, using three sorts of vaccine: 1. A so-called "attenuated" living virus vaccine, administrable by parental route. 2.

[Characteristics of viruses multiplying in cell lines in suspension and their correspondent vaccines].

The characteristics of the viruses produced from cell lines developed in suspension and the vaccines for which they are used should be judged by methods which allow to ensure in all cases their innocuity and efficacity. Innocuity is essentially dependent upon the purity of the viral preparation which should contain a minimum of foreign proteins (due either to the cell or the culture medium) and certain antibiotics. Furthermore, the absence of oncogenic properties of the inactivated viral suspensions should be shown, in addition to their specific innocuity.