Lisowski J

Immunoglobulins of colostrum—III: Comparative studies of ovine serum and colostral IgG1 and IgG2

Abstract Comparative studies of physico-chemical properties of ovine serum and colostral IgG1 and IgG2 are described. Hydrodynamic properties, amino acid compositions, carbohydrate contents, and ORD and CD spectra were compared. Colostral immunoglobulins showed higher content of β-structure in comparison with serum immunoglobulins. Different amino acid compositions of serum and colostral immunoglobulins, especially in case of IgG2 was shown. A polypeptide with high content of proline and glutamic acid residues accompanying colostral IgG2 was isolated. The results obtained are suggesting that ovine colostral IgG2 is locally synthesized in mammary gland, wherease colostral IgG1 might be a mixed population of molecules locally synthesized and transferred from the serum.

A new method of preparation of specifically purified anti-TNP antibodies.

Abstract A new method of preparation of specifically purified rabbit anti-TNP antibodies is described, in which immunoadsorbents prepared from TNP-BSA and PAB-cellulose and AE-cellulose are used. To increase efficiency, TNP-BSA was reduced and alkylated in 6 M guanidine hydrochloride solution before coupling with diazotized PAB-cellulose. For coupling with AE-cellulose in the presence of cyclohexyl-morpholinyl-carbodiimide no pretreatment of TNP-BSA is necessary. In the case of PAB-cellulose 92 mg TNP-BSA were bound to 1 g of the cellulose carrier, and in case of AE-cellulose 100 mg of TNP-BSA was linked to 1 g of the cellulose. The best results were obtained with PAB-cellulose-TNP-BSA immunoadsorbent and 0.01 M picric acid as eluting agent. With low affinity rabbit anti-TNP antibodies 92% yield of 85–100% precipitable antibody was achieved reproducibly. With other methods, only 12–48% yield of 50–90% precipitable antibodies was obtained.