Cytotoxicity reactions against target cells infected with rabies virus.

Some aspects of the cytotoxicity reactions were studied in the rabies system. The antibody-dependent complement cytotoxicity (ADC), the cellular cytotoxicity (CC), and the antibody-dependent cellular cytotoxicity (ADCC) are shown, being the cytotoxic effect as evidenced by the 51Cr released from the cells infected with the Pasteur strain of rabies virus. Some parameters such as time of cellular infection, the amount of infected cells, the concentration of complement, and the incubation time of the ADC reaction, which help to increase the performance of this reaction, are discussed. The detection and the level of the cellular response against the Pasteur strain of rabies virus in immunized mice is shown. Evidence is presented that in the ADCC test, specific human antibodies and non-immune human lymphoid cells are able to mediate in vitro lysis of cells infected with rabies virus. A comparison of the ADCC test with serum neutralization and immunoenzymatic tests is shown.

[Role of interferon in rabies immunity]. / Rôle de l'intérferon dans l'immunité antirabique.

Cell cultured rabies vaccines, usually induce a good production of interferon. A comparative study shows that vaccines from primary explantation cell cultures are better interferon inducers. Taking into account the importance of this induction in rabies vaccination, a study showing the role of leucocyte interferon (alpha-type) is achieved. Results show that leucocyte interferon (originating from the Red Cross, Osaka, Japan and Institut Pasteur Production, Paris) inhibits the formation of fluorescent inclusions and the production of infectious particles in MRC5 cells inoculated with a fixed rabies strain. On the other hand modification of the thymus weight was studied following injections of interferon inducer vaccines and after challenge with a street rabies virus.

[Evaluation of an experimental rabies vaccine by the oral and intestinal route with inactivated vaccines, concentrated or non-concentrated]. / Evaluation d'une vaccination rabique expérimentale par la voie orale et intestinale avec des vaccins tues, concentrés et non concentrés.

Application of beta-propiolactone inactivated rabies vaccine prepared in bovine embryo kidney cells, concentrated or non concentrated, by intestinal or oral route resulted in antibody production in rats and cats. 80-100% of vaccinated rats were protected against challenge with street rabies virus. The same vaccines (lyophilized in gelatin capsules) stimulated antibody production in more than 50% (5/8) cats which received the vaccine by the oral route.

Interferon y vacunacion antirrabica. / Interferon and antirabies vaccination

Dos lotes de interferon de leucocitos humanos actuan sobre la multiplicacion del virus rabico in vitro. Esta accion es mas efectiva cuando el virus y el interferon se agregan simultaneamente a la celula. La presencia del interferon provoca gran reduccion de la sintesis en las celulas de las nucleoproteinas virales. Los ratones con rabia mueren por ausencia de celulas T, debido a una citolisis masiva del timo y no a la presencia del virus. Las vacunas antirrabicas capaces de producir interferon protegen a este organo por un mecanismo aun no establecido. Una comparacion entre la inmunidad humoral y la proteccion con diferentes vacunas humanas de cultivo de celulas ha mostrado que a pesar de una buena prueba de potencia y la capacidad de inducir anticuerpos, hay diferencias en sus capacidades interferogenicas. Las proteccion contra el desafio con virus vivo de la calle se relaciona directamente con la capacidad interferogenica de la vacuna

[Comparison of inactivated rabies vaccines obtained from diploid and polyploid heterologous cells (Hak, BHK, and Vero)]. / Etude comparative de vaccins rabiques inactivés obtenus à l'aide de cellules hétérologues diploides et polyploides (Hak, BHK et Véro).

Homologous or heterologous diploid or polyploid cells have been established as good producers of virus. In this study we present three types of experimental inactivated antirabies vaccines obtained under identical conditions from three types of cells. The study concerns the following characteristics of the vaccines: protecting powers, rabies antigens and major polypeptidic components; this study was performed on supernatants of tissue cultures and concentrated and purified vaccines. Moreover, some cellular and serum contaminants as well as minor rabies proteins were analysed in the viral solutions. It, thus, appears that all these types of vaccines have a similar protecting power (Number of 50% protective doses/micrograms viral protein).

Evaluation and comparative studies of inactivated rabies vaccines obtained in the heterologous diploid and polyploid cells (HAK, BHK and VERO).

This study is concerned with the following characteristics of the vaccines: 1.) protecting power, 2.) rabies antigens and 3.) major polypeptide components. This study was performed on supernatants of tissue cultures and on concentrated and purified vaccines. Moreover, some cellular and serum contaminants, especially the proteins produced by BHK cells, as well as minor rabies proteins, were analysed in the viral solutions. Thus, it appears that all three types of vaccines have a similar protecting power (Number of 50% protective doses/micrograms viral protein).

[Molecular study in polyacrylamide gel of polypeptides of several strains of rabies virus]. / Etude moléculaire en gel de polyacrylamide des polypeptides de plusieurs souches de virus rabique.

Comparative study of structural polypeptides of five rabies virus strains (serotype 1) and one serotype IV, demonstrates difference in molecular weight of the envelope polypeptides M1 and G of all strains. There is little difference between the structural polypeptides N, M2 and probably L. Some purified strains have been treated by trypsine to localize the position of polypeptides. There was no difference between the four major polypeptides of complete and defective virus. Pasteur strain cultivated on different cells shows very little difference in molecular weight of the four major polypeptides.

Use of an enzyme immunoassay with protein A for rabies antigen and antibody determination.

The rabies antigen quantitation reported here is based on the principle of an enzyme immuno micro assay (EIA) using antigen coated polystyrene microtiter plates. In a first step antibodies of known specificity are partially blocked by the antigen to be titrated; in a second step the free remaining antibodies are determined by EIA. Antirabies vaccines, purified virus or rabies glycoprotein were assayed by that micro-method in comparison with the double neutralization test in tissue culture. Moreover, we report results obtained by EIA on the rate of antigen bonding to a solid carrier in order to prepare immunoadsorbents and the usefulness of EIA to monitor specific immunoglobulin elution.

Concentration and purification of human rabies vaccines : results.

Concentration of two types of rabies tissue culture vaccine has been realized with Amicon hollow fibers. The coefficient of purification obtained on Sepharose 6B chromatography is 2,3 to 4,6 with a recuperation of 25% to 30% of the haemagglutination power for one of the vaccines. The control of glycoprotein contents has been realized by means of classical technics as well as the rapid immunoenzymatic test. (I.E.T.).