Complement modulation assay

Screening systems for complement activity are most commonly based on its haemolytic properties, involving a spectrophotometric measurement of the haemoglobin released at = 414 nm. The amount of haemoglobin that is released reflects the degree of lytic action. Complement modulation tests commonly applied are based on the assay models as described by Mayer in 1971 [5] and by Platts-Mills and Ishizaka in 1974 [6] for the classical and the alternative activation pathways, respectively. A haemolytic complement assay on microscale for classical and alternative pathway activation was presented by Klerx et al. in 1983 [7]. 

It can be concluded from this review that a whole range of low molecular weight compounds exhibits complement-modulating properties. There is little doubt that the use of complement-based assays to guide the isolation of active compounds from plants and plant extracts will add more natural products with a variety of structures to this list. 

Numerous reviews have documented immune modulation in response to metal, pesticide and organic contaminants in fish4,19,37,135. Assays traditionally used to assess perturbations of immune function in fish fall into three broad categories pathogen challenge models, assays that monitor immune suppression/activation or immuno-pathology. Immune suppression/activation is usually measured with assays of phagocytosis, respiratory burst, cell proliferation, as well as quantification of soluble factors such as lysozyme, serum antibody, CRP or complement. 

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