Learn IL18 in 3 minutes | Interleukin-18

Editor's Notes

• #2: Does your next experiment involve IL18? This video is for scientists who want to run Western blot, IHC, flow or other immunoassays against IL18.
• #3: We will cover some basic facts, protein expression, and IL18’s expected behavior in Western blot. All information in this video is based on public information and no proprietary experimental evidence was used.
• #4: Topic 1: Quick facts about IL18. Interleukin-18 is a member of the IL1 superfamily that is primarily involved in the regulation of T-helper 1 cells and natural killer cells immune responses. While most cytokines contain the signal peptide for extracellular release, the IL18 gene lacks this signal peptide just like other IL-1 family members. IL18 synergizes with IL12 to induce the production of various proinflammatory cytokines and chemokines, especially IFN-gamma. High levels of IL18 are detected in patients with severe inflammatory disorders and potentially fatal reactions characterized by a cytokine storm. The precursor of interleukin 18 is 193 amino acids long and runs about 24 kilodaltons on Western blot while the mature form is 157 amino acids long and runs about 18 kilodaltons on Western blot.
• #5: Topic 2: Where is IL18 expressed? IL18 is primarily expressed by dendritic cells, neutrophils, monocytes, macrophages, and epithelial cells. It is also constitutively expressed within the cytoplasm and nucleus of a variety of hematopoietic cells, non-hematopoietic cells, and keratinocytes. High interleukin 18 protein expression is found in the cerebellum, respiratory system, proximal digestive tract, gastrointestinal tract, female tissues, skin, and lymphoid tissues. Lower levels of protein expressions are found in the liver, gallbladder, kidney, urinary bladder, and male tissues. You can find more information on protein atlas dot org to check out which cell lines express IL18 and which ones don’t. This information will come in handy when designing positive and negative controls for western blot and immunohistochemistry.
• #6: Topic 3: IL18 in Western blotting. Antibody specificity can make or break an experiment. After looking through Western blot images from publications and antibody companies, researchers can typically expect two bands in an interleukin 18 western blot, the inactive 24 kilodaltons precursor and the mature biologically active IL18 at approximately 18 kilodaltons.
• #7: Topic 4: Some interesting facts about interleukin 18. IL18 not only acts on the immune system, but also on other systems and physiological processes, such as the endocrine system, the nervous system, and bone metabolism. Studies in animal models have demonstrated the unique, dual effect of IL18 to both inhibit and promote tumor progression and metastasis. Because of this, since its discovery in 1989, many studies have been designed to investigate the antitumoral activity of IL18 as well as the possibility and efficacy of using interleukin 18 for therapeutic purposes.