Interleukin-2 (IL-2) is an important regulator of cellular immunity in mammals. For many years, our inability to identify the expression of this cytokine in marsupials hindered our capacity to progress studies in metatherian immunology. Here, we report the use of molecular techniques to characterise the IL-2 gene for the tammar wallaby (Notamacropus eugenii) and the Tasmanian devil (Sarcophilus harrisii), which allowed the prediction of the structure and probable functions of the IL-2 proteins of these species. Deduced marsupial IL-2 proteins show considerable sequence identity to each other and to common brushtail possum (Trichosurus vulpecula) IL-2 (≥65%) but shared only 35% (tammar wallaby) and 32% (Tasmanian devil) identity with human IL-2. This difference means that reagents used to study IL-2 in human and other eutherians are unlikely to cross-react with marsupials. As a key step in furthering our ability to study cellular immune responses in marsupials and, more specifically, the susceptibility of macropodoid marsupials to intracellular pathogens, a polyclonal antibody was designed for the detection and future investigation of tammar wallaby IL-2 protein expression. The molecular data and polyclonal antibody described herein will support our development of gene probes and immunological reagents that will aid studies of infection and disease in marsupials.
Characterization of the antimicrobial peptide family defensins in the Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus), and tammar wallaby (Macropus eugenii)
