Volume 59 (2009) Issue: 2009 No#5-6

Immunoglobulins in pigs vaccinated with a subunit E2 and an attenuated C strain vaccine against classical swine feve

Author(s): Terzić Svjetlana, Bilandžić Nina, Jemeršić Lorena, Logomerac Vesna, Cvetnić Ž, Šandor Ksenija, Oršolić Nada, Valpotić I

Keywords:immunoglobulins, pigs, classical swine fever, vaccination

The aim of this study was to detect changes in the concentration of serum immunoglobulins following vaccination against classical swine fever (CSF) with an attenuated C strain and a subunit E2 vaccine. Furthermore, the adjuvanticity of an attenuated parapoxvirus ORF virus for the subunit vaccine against CSF was evaluated. Peripheral blood samples were collected before the vaccination and at post-vaccination days 4, 10, 21 and 28. The samples were assessed by a colorimetric method for the detection of total proteins, as well as albumin, IgA and IgM levels and by radial immunodiffusion to record the IgG level. Our findings are in accordance with the normal concentrations of porcine IgG, IgA and IgM. However, a significant increase of some immunoglobulin classes was recorded. The increase of the IgM level in vaccinated pigs confirmed an early development of humoral immunity. Interestingly, the subunit E2 vaccine induced the increase of IgM earlier then did the attenuated C strain. Since the IgG concentratiom was not significantly increased we assumed that the period of 28 days following vaccination was too short to detect any changes in the IgG level, thus reflecting a late humoral immune response. Although, IgA antibodies are mostly responsible for humoral immunity at the mucosal surfaces, in our experiment the attenuated C strain induced a significantly higher production of this immunoglobulin class in the serum very early (on day 4) following vaccination. This could be ascribed to the affinity of IgA antibodies to neutralize or agglutinate virus particles. Early appearance (4 and 10 days after the vaccination) of a significantly higher concentration of IgG and IgM could be induced by the ORF virus strain D1701 applied as an adjuvant.