Cytokine assays

After incubation, the supernatants of the ceU cultures can be used for the cytokine assay by capture enzyme-linked immunosorbent assay (ELISA) using specific antibody pairs and recombinant cytokine standards and ELISA plates. 

Anti-arthritic effect. Oral administration of AJA, a cannabinoid acid devoid of psychoactivity, reduced joint tissue damage in rats with adjuvant arthritis. Peripheral blood monocytes (PBM) and synovial fluid monocytes (SFM) were isolated from healthy subjects and patients with inflammatory arthritis, respectively, treated with AJA (0-30 mM) in vitro, and then stimulated with lipopolysaccharide. Cells were harvested for messenger RNA (mRNA), and supernatants were collected for cytokine assay. Addition of AJA to PBM and SFM in vitro reduced both steady-state levels of interleukin-ly (IL-ly) mRNA and secretion of IL-ly in a concentration-dependent manner. Suppression was maximal (50.4%) at 10 mM AJA (p < 0.05 vs untreated controls, n = 7). AJA did not influence tumor necrosis factor-a (TNF-a) gene expression in or secretion from PBM . 

This review will describe the biological functions and regulation of the recently identified cytokines—interleukins, chemokines, and peptide growth factors—their intracellular signal transduction and role in certain diseases, and different cytokine assay methods and their clinical applications. 

As with the measurement of other analytes, cytokine assay methods changed from the original bioassays to immunoassays, flow cytometric analysis, and mi-croarray technology. 

This volume continues our objective of expanding the intellectual horizon of clinical chemistry. Included are chapters on Clinical Applications of Cytokine Assays Diagnosis and Treatment of Acute Pancreatitis Mitochondrial Mutations and Mitochondrial Diseases Pathobiochemistry of Nephrotic Syndrome Total Antioxidant Capacity Autoantibodies to dsDNA, Ro/SSA, and LaSSB in Systemic Lupus Erythematosis and Lymphoid Malignancies and Immunosuppressive Analysis. The meld of analytical, anatomical, subcellular, and molecular sciences represented by these subjects will continue to evolve and expand. Clinical chemistry is a vibrant and vital profession. Future volumes, their editors, and their contributors will undoubtedly be an important part of the practice and science of clinical chemistry. 

Whiteside TL (1994), Cytokine measurements and interpretation of cytokine assays in human disease, J. Clin. Immunol. 14 327-339. 

For example, in an FRET assay for the research of a receptor ligand inhibitor, the presence of a library componnd which flnoresces at the acceptor wavelength will lead to a false negative resnlt (compensation of the decrease of the FRET signal by the fluorescent componnd) on the contrary, the same compound would give a false positive result in a cytokine assay nsing a sandwich format with two monoclonals (compound fluorescence will be interpreted as an FRET increase). In both cases, the use of HTRF would have corrected for the fluorescence of the compound in the acceptor channel. 

The demonstrated ZnO NR-enabled fluorescence sensitivity is even more remarkable, when considering the fact that such fluorescence enhancement of ZnO NR platforms is achieved without the use of chemical and biological ampliflcation processes, major improvements of detection apparatus and analysis software, or application of specially designed fluorophores. Although telomerase and cytokine assays are discussed in this section as example cases, the versatility and general applicability of ZnO NR-based assays can be extended to other disease-marker or biomarker systems. 

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