[Immunosuppression in an experimental infection with the infectious rhinotracheitis virus]. / Imunosupresiia pri eksperimentalna infektsiia s virusa na zarazniia rinotrakheit.

The changes in the immune status of the calves infected with bovine herpes virus-1 inducing infectious rhinotracheitis were studied. The virus was introduced by intratracheal inoculation of 5 cm3 suspension with minimal concentration of 10(-7) CPU50 per 1 cm2 from the Cervena voda strain cultivated in calf kidney culture. An infection of moderate seriousness and characteristic clinical manifestations was caused. On the 2nd, 5th, 10th and 15th day after the infection lung lavage was carried out and samples were taken from the peripheral blood. The number, viability and differential distribution of the alveolar macrophages and phagocytic and microbicidal ability showed a tendency to decrease during the acute phase of the infection (the 2nd-5th day) followed by a slow restoration in the period of convalescence (the 15th day). Some parameters of the systemic immunity--number of the plaque-forming and the rosette-forming cells, differential and absolute number of leucocytes in the peripheral blood--also had similar dynamics. The changes in the local and in the systemic, in the cell and humoral immunity were connected to the pathogenesis of the infection and the immune suppressive properties of the agent. The rhinotracheitis infection is indicative of the character of changes in the immune status at herpes virus infections and, on the other hand, it can be used as a model for testing immunostimulators of recovery effect.

[The immunostimulating action of suramin in infection with the infectious rhinotracheitis virus]. / Imunovuzstanovitelno deistvie na suramin pri infektsiia s virusa na zarazniia rinotrakheit.

The immunostimulating antiviral preparation suramin has a favourable effect on the process and outcome of an experimental infection with the virus of infectious rhinotracheitis (bovine herpes virus type 1, BHV1), thus reducing the gravity of the clinical course and increasing the survival rate. The therapeutic protective effect of the preparation is expressed in the prevention of virus-induced immunosuppression which is markedly strong during the acute phase of the infection process. Suramin restored the number, viability, relative share in the bronchial lavage population, phagocytic and microbicidal capacity of the alveolar macrophages--a major factor of the local defence mechanisms of the lung. In a similar way suramin influenced some parameters of the systemic immunity (number and differential count of polymorphonuclear phagocytes, plaque- and rosette-forming cells). The application of suramin in doses lower than those used for virus inhibition and its considerable action on different mechanisms of the immune system suggested that the preparation's therapeutic effect could be related mainly to its immunostimulating properties.