Volume 60 (2010) Issue: 2010 No#2-3

ELECTROPHORETIC AND IMMUNOELECTROPHORETIC CHARACTERISTICS OF IgG AS A CONSTITUENTS OF PEG PRECIPITABLE IMMUNE COMPLEXES IN PRERUMINANT CALVES' SERA

Author(s): Fratrić Natalija, Ilić Vesna, Milošević-Jovčić Nadežda, Stojić V

Keywords:calves, IgG, immune complexes, PEG assay

Preruminant calves encounter numerous antigens, and formation of immune complexes is necessary for antigens elimination. The capability of immunologically immature calves to form immune complexes has not yet been studied in detail. For immune complexes studies, selective precipitation by PEG was performed, in combination with agarose gel electrophoresis and immunoelectrophoresis, with an aim to determine some properties of IgG, as constituents of immune complexes. In our previous work it was shown that the level of PEG precipitable immune complexes increased in the period from birth to 48- hours of life, decreased at day 10, increased in one month old animals, and after that, stayed unchanged until 4th month of age. Electrophoretic and immunoelectrophoretic analysis showed that until one motnth of age, calves' sera and PEG precipitates contained only one part of IgG molecules which corresonded to fast, anionic
globulins. Although at the age of one month, preruminant calves' sera contained all molecular forms of IgG molecules present in the sera of adult cattle, only one part of serum IgG (fast, anionic IgG) was precipitated by PEG. In older calves, all molecular forms of serum IgG had the capacity to form PEG precipitable immune complexes. Presented data, as well as the results of our previous work, can be used as parameters with reference to physicochemical and immunochemical characteristics of IgG immune complexes of preruminant calves under pathological conditions.