A hemolysis-hemagglutination assay for characterizing constitutive innate humoral immunity in wild and domestic birds.

Department of Biology, University of Missouri, 8001 Natural Bridge Road, St Louis, MO 63121-4499, USA.
Developmental & Comparative Immunology (Impact Factor: 3.71). 02/2005; 29(3):275-86. DOI: 10.1016/j.dci.2004.07.006
Source: PubMed

ABSTRACT Methods to assess immunocompetence requiring only a single sample are useful in comparative studies where practical considerations prevent holding or recapturing individuals. The assay for natural antibody-mediated complement activation and red blood cell agglutination described here, requiring approximately 100 microl of blood, is highly repeatable. The effects of complement deactivation, 2-mercaptoethanol (2-ME), age, and lipopolysaccharide (LPS)-induced sickness response were examined to validate comparisons among diverse avian species. Complement deactivation by heating significantly reduces lysis and treatment with 2-ME reduces both lysis and agglutination. Lysis and agglutination both increase with age in chickens; LPS treatment does not influence these variables in 11-week-old chickens. In a comparison of 11 species, both lysis (0.0-5.3 titers) and agglutination (1.8-8.0 titers) vary significantly among species. Accordingly, this assay can be used to compare constitutive innate humoral immunity among species and with respect to age, sex, and experimental treatments within populations.

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