Laboratory protocols for the quantitation of cytokines by bioassay using cytokine responsive cell lines.

Cytokines have been shown to be involved in many physiological processes, including the maintenance and control of a competent haematopoietic/immune system. Abnormal cytokine secretion or synthesis can cause a wide range of pathological disorders. Cytokines have also been shown to have therapeutic potential in many diseases. In order for the role of cytokines to be evaluated in normal and pathogenic processes, it is vital that appropriate assay systems are used to measure their levels in different biological fluids. Whilst immunoassays maybe a more convenient method for quantitating cytokines, they only measure immunologically reactive material. They may or may not detect biologically inactive material, such as cytokines bound to soluble receptors or degraded cytokine molecules. Bioassays, however, detect biologically active cytokines and can be as accurate and precise as immunoassays. The purpose of these protocols is to provide practical stepwise methods for the bioassay of cytokines using cytokine responsive cell lines. They include tables of the most useful currently available cell lines for the detection of cytokines and how to maintain them. In addition, these protocols provide all the materials and methods in a logical step-by-step procedure to carry out bioassays. Information is provided on possible pitfalls and general problems associated with bioassays and how to overcome them. These protocols should be valuable to scientists new to the cytokine field as well as experienced scientists who require a consensus methodology and access to information on cell lines useful for cytokine bioassays.