Identification and purification of armadillo (Dasypus novemcinctus) immunoglobulins: preparation of specific antisera to evaluate the immune response in these animals.

In this work we describe the purification and characterization of armadillo immunoglobulins. The IgM was precipitated using low-strength ionic solution and further purified by filtration through Sephadex G-200. The IgG was obtained in pure form by precipitation of serum with ammonium sulfate and DEAE-cellulose ion exchange chromatography. The purity of these immunoglobulins was evaluated by polyacrylamide gel electrophoresis. The results showed 28-kDa light chains and 55-kDa and 70-kDa heavy chains for IgG and IgM, respectively. The rabbit antibodies against these molecules were used to prepare fluorescein (FITC) and peroxidase conjugates. The FITC conjugate was used to quantify IgM-bearing lymphocytes. An average of 17% of peripheral blood lymphocytes were sIgM+ from 14 healthy animals. Additionally, in the same animals we quantified lymphocytes with the capacity to form rosettes with sheep red-blood cells; the average for this marker was 10%. Also, the production of crossreacting antibodies to BCG was evaluated in healthy and Mycobacterium leprae-inoculated animals using the peroxidase conjugates. All animals with active infection recognized BCG antigens.