Role of acute phase proteins in the immune response of rabbits infected with Trypanosoma evansi.

The aim of this study was to characterize the response of acute phase proteins (APP) in rabbits experimentally infected with Trypanosoma evansi (T. evansi), and to relate the findings with serum immunoglobulins levels, in order to verify the relation between APP and the immune response of rabbits. A total of 12 animals were used in this experiment and divided into 2 groups, control and infected, of six rabbits each. The experimental period was 118 days, and blood was collected on days 0, 5, 20, 35, 65, 95 and 118 post-infection (PI). The infection with T. evansi stimulated APP and immunoglobulins production, once the infected animals showed an increase in C-reactive protein, haptoglobin, alpha 2-macroglobulin and IgM levels. The elevation in IgM levels observed in this study, when related to the increase in C-reactive protein and haptoglobin levels, suggests the involvement of these proteins in host defense against flagellated protozoa, with possible participation in the control of the parasitemia in rabbits infected with T. evansi.