Quantification of infectious bursal disease viral proteins 2 and 3 in inactivated vaccines as an indicator of serological response and measure of potency

• Published in: Avian pathology Vol. 33; no. 2; pp. 126 - 132
• Main Authors: Maas, R, Venema, S, Kant, A, Oei, H, Claassen, I
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 01-04-2004; Taylor & Francis Ltd
• Subjects: Animals; antibodies; antigenic variation; Antigens, Viral - analysis; Antigens, Viral - immunology; Birds; Birnaviridae Infections - immunology; Birnaviridae Infections - prevention & control; Birnaviridae Infections - veterinary; chickens; Chickens - immunology; Chickens - virology; Disease; heterogeneity; inactivated vaccines; Infections; infectious bursal disease; Infectious bursal disease virus; Infectious bursal disease virus - immunology; Poultry Diseases - immunology; Poultry Diseases - prevention & control; protection; Proteins; Specific Pathogen-Free Organisms; Vaccines; Vaccines, Inactivated - chemistry; Vaccines, Inactivated - immunology; viral proteins; Viral Structural Proteins - analysis; Viral Structural Proteins - immunology; Viral Vaccines - chemistry; Viral Vaccines - immunology; virulent; virus; vp2
• ISSN: 0307-9457; 1465-3338
• DOI: 10.1080/03079450310001652121

Viral protein 2 and viral protein 3 (VP2 and VP3) were quantified in a series of inactivated infectious bursal disease oil emulsion vaccines using enzyme-linked immunosorbent assay, and the dependence of the serological response on vaccine antigen content was studied. Large differences in antigen content, up to 50-fold, were found between vaccines. Neutralizing antibody titres at 3 to 6 weeks after vaccination varied from 3 log2 to 16 log2. None of the vaccines induced an antibody titre equal to that of the reference serum used as an indicator of sufficient potency in the European Pharmacopoeia. Neutralizing antibody titres after vaccination correlated highly with the VP2 content of the vaccines. A significant correlation was also found between the VP3 content and the antibody response. Our data illustrate that the antigen content of inactivated infectious bursal disease vaccines is a reliable indicator of the protective serological response after vaccination, and consequently could be used as a measure of vaccine potency. This holds true for both VP2, the antigen that induces neutralizing antibodies, as well as for VP3, which does not induce neutralizing antibodies.