Antigen distribution and humoral response in the lizard, Agama caudospinosum, after injection with Leishmania agamae.

The response of the spiny-tailed agamid lizard, Agama caudospinosum, to administration of Leishmania agamae promastigotes was investigated. Lizards given a single injection of promastigotes showed no signs of clinical infection. Neither promastigotes nor amastigotes were found in blood and tissue impression smears, nor in blood and selected body organ cultures. However, parasite antigens were demonstrated by an immunoenzyme method only in the liver, small intestine, stomach, spleen and kidney. Non-precipitating serum antibodies with gamma-electrophoretic mobility were detected by enzyme-lined immunosorbent assay 1 week post-injection and a maximum titre was reached after 6 weeks. The mean immune serum protein concentration increased significantly (P less than 0.005) about two-fold over the controls after injection. Decreases occurred in the beta-globulin region of anti-L. agamae sera (P less than 0.01) whilst the gamma-globulin fraction was increased (P less than 0.005) following electrophoresis on cellulose acetate membranes. C-reactive protein was not detected in any of the sera. These data show that although A. caudospinosum failed to become infected by L. agamae promastigotes, which had been isolated from agamids, it did exhibit antigen distribution and a humoral response similar to other reptiles.