Purification and initial characterisation of koala immunoglobulins*
R. Wilkinson, M. Allanson, V. Kolega, D. Lawrence and S. Neville
Central Veterinary Laboratories (VETLAB), Department of Agriculture, Frome Road, Adelaide, S.A. 5000, Australia
The production of koala immunoglobulins (lg) was elicited by the immunisation of a koala (Phascolarctos cinereus) with bovine serum albumin. This Ig was then purified using the highly specific techniques of affinity chromatography. The purified protein was compared with a "'potential" koala Ig protein which was subsequently purified by Protein G chromatography and both proteins were further characterised by agarose/SDS-PAGE and immunoelectrophoresis. Results indicate that koalas do produce Ig in response to antigen challenge, koala Ig has a higher net negative charge than that seen in most other mammals and possibly two subclasses of IgG and IgM are present in normal koala serum.