Background: The immunomodulatory properties of Nigella sativa seed, as a basis of its
clinical applications by many cultures have been reviewed. Thymoquinone (TQ) is one of the major
bioactive components of the volatile oil of N. sativa seeds.
Methods: The review on immunomodulatory and anti- inflammatory effects of TQ was focused on
published literature in the English language. The literature search was conducted in the following
databases: PubMed (2004-2017), Scopus (2004-2017) and Google Scholar (2004-2017). The keywords used
were the following terms: thymoquinone, immunomodulation, inflammation, autoimmune and asthma.
Results: The present investigations provide a comprehensive review of the ability of TQ to
modulate inflammation and immune-related disorders in the various important disease states. This
finding showed that TQ has anti-inflammatory properties that prevent the biosynthesis of important
mediators in inflammatory processes and asthma such as 5-LO, COX, PGD2 and LTs. TQ also
reduced LPS-induced proinflammatory cytokines such as interleukins (ILs) and TNF-α. In addition,
TQ showed immunomodulatory role in the cellular and humoral immunity. This study also found
that TQ improves imidacloprid toxicity through reducing oxidative stress and increasing
chemokinesis, chemotaxis, phagocytic activity, antibody levels and the hemagglutination of
immunoglobulins as well as by reducing serum MDA levels and hepatic enzymes.
Conclusion: The study indicated the beneficial effects of TQ in immune-related diseases, however,
well designed clinical trials in humans are required to confirm these effects.