[The pathogenesis of postvaccinal complications]

Area of Science:

• Immunology
• Vaccinology
• Pathogenesis

Background:

• Vaccines can induce paraspecific reactions, including autoimmunity, immunosuppression, and inflammation (reactogenicity).
• These reactions are key factors in post-vaccination complications.
• Previous studies have demonstrated paraspecific reactions in animal models following vaccinia virus infection.

Purpose of the Study:

• To investigate paraspecific reactions to vaccines.
• To demonstrate these reactions in animal models.
• To develop a method for assessing vaccine innocuity and tolerance.

Main Methods:

• Experimental vaccinia virus infection in guinea pigs and rabbits.
• Assessment of cell-mediated hypersensitivity to brain antigens.
• Detection of humoral anti-brain antibodies.
• Evaluation of immune response to sheep erythrocytes in mice using plaque-forming cell assays.
• Hemolytic plaque assay in mice to determine vaccine reactogenicity.

Main Results:

• Vaccinia infection induced cell-mediated hypersensitivity and humoral anti-brain antibodies in animal models.
• Pre- or co-administration of vaccinia virus significantly reduced immune response to sheep erythrocytes in mice.
• The hemolytic plaque assay correlated with macrophage lysosomal activity, reflecting vaccine reactogenicity.

Conclusions:

• Paraspecific reactions to vaccines can be demonstrated and studied in animal models.
• A hemolytic plaque assay offers a potential method for evaluating the safety and tolerance of new vaccines.
• Understanding and assessing these reactions is crucial for preventing post-vaccinal complications.