[Preparation of porcine IgA and its detection using the fluorescent antibody technic]

The preparation of immunoglobulin A (IgA) from porcine colostrum, intestinal content and serum is described. The best results were achieved with colostrum, from which an antigen of satisfactory purity was prepared by purification on Sephadex G-200, on DEAE cellulose and subsequent filtration on Sephadex G-200. The serum to this antigen raised in rabbits was adsorbed to an immunoadsorbent from porcine serum (PS) or porcine IgG. The adsorbtion of the serum against secretory IgA (SIgA) to PS removed its undesirable heterologous and nonspecific reactivity. The anti-SIgA serum adsorbed in this way still reacted with IgA from porcine serum. In the direct and indirect immunofluorescent staining we detected the main antigenic determinants of the SIgA molecule, i. e. the heavy chains and the secretory component.