Meeting Abstract
P3.123 Sunday, Jan. 6 CHARACTERIZATION OF COMPLEMENT-SYSTEM ACTIVITY OF COMMON PIGEON PLASMA (Columba livia) CAVIEDES-VIDAL, E*; LOPEZ-CATIVA, L; MOLINA-MARINO, L; Univ Nac de San Luis – Consejo Nac de Inv Científicas y Técnicas; Univ Nac de San Luis; Univ Nac de San Luis – Consejo Nac de Inv Científicas y Técnicas enrique.caviedes@gmail.com
The complement system (CS) is an important component of the innate immune system of vertebrates that protects against infectious agents. We used the rabbit red blood cell (RRBC) hemolysis assay to assess and characterize the activity of CS in pigeon plasma (pool). Immediately before the assay, plasma was treated with two inhibitors (EDTA and heat) to make sure that hemolysis was due to CS activity. Plasma samples were preincubated in a thermoregulated water bath, then a solution of RRBC (2% v/v) was added and the mix incubated again at selected temperature. After the incubation, samples were centrifuged, supernatant was loaded on a plate and the released hemoglobin was read at 540 nm. We evaluated: A) the effect of the temperature on CS activity by incubating the reaction mix at different temperatures. B) the kinetics of hemolysis by incubating plasma samples with RRBC and stopping the reaction at different times. C) the effects of the plasma concentration on RRBC lysis, a series of assays with increased concentrations of plasma was performed. The reaction showed a positive relationship between incubation temperature and hemolysis reaching a maximum at 41°C. Hemolytic activity was detected with a concentration of 10 % pigeon plasma and was total at 20 %. RRBC lysis was apparent after 2.5 min of incubation and increased steadily until 25 min, when it became constant. Considering that pigeons are an extremely successful species that has been widely spread in rural and urban areas, that they harbor a diverse parasite fauna and are potentially associated with zoonotic events, to assay the complement system as an innate immune component in the resistance to disease may be an important tool. Funded by PICT 97-01320 to EC-V
