CHICKEN EGG ANTIBODIES FOR IMMUNOHISTOCHEMICAL LABELING OF GROWTH-HORMONE AND PROLACTIN IN BOVINE PITUITARY-GLAND

We describe the production of polyclonal chicken antibodies specific f or bovine growth hormone (bGH) and prolactin (PRL). Antibodies were ge nerated by immunization of laying hens with recombinant bGH (rbGH), pi tuitary derived bGH (pbGH), and ovine PRL (oPRL). After the lipoprotei n fraction was removed by dextran sulfate precipitation the antibodies were isolated from the egg yolks by ammonium sulfate precipitation. I mmunization with rbGH and oPRL generated large amounts of specific ant ibodies, as revealed by ELISA and Western blot analysis. Antibodies ag ainst pbGH showed pronounced crossreactions with oPRL. The antibodies against rbGH and oPRL were well suited for sensitive and specific labe ling of the GH- and PRL-synthesizing cells in bovine pituitary glands by immunohistochemistry. In addition, a quick and sensitive procedure for demonstration of both bGH- and PRL-synthesizing cells in a single paraffin section by double immunohistochemistry is presented. The chic ken anti-bGH antibodies showed excellent results in combination with r abbit anti-PRL antibodies. The main advantage of avian antibodies in d ouble immunostaining methods is the lack of crossreactions between avi an antibodies and mammalian immunoglobulins and receptors which bind t o the crystalline fragment of mammalian immunoglobulins (Fc receptors) .