Abstract
Gram-negative bacterial cell surface component lipopolysaccharide (LPS) and its active principle, lipid A, exhibit immunostimulatory effects and have the potential to act as adjuvants. However, canonical LPS acts as an endotoxin by hyperstimulating the immune response. Therefore, LPS and lipid A must be structurally modified to minimize their toxic effects while maintaining their adjuvant effect for application as vaccine adjuvants. In the field of chemical ecology research, various biological phenomena occurring among organisms are considered molecular interactions. Recently, the hypothesis has been proposed that LPS and lipid A mediate bacterial–host chemical ecology to regulate various host biological phenomena, mainly immunity. Parasitic and symbiotic bacteria inhabiting the host are predicted to possess low-toxicity immunomodulators due to the chemical structural changes of their LPS caused by co-evolution with the host. Studies on the chemical synthesis and functional evaluation of their lipid As have been developed to test this hypothesis and to apply them to low-toxicity and safe adjuvants.
Highlights
The immunomodulatory effects triggered by bacteria have long been identified [1].Tumor burden decrease and regression caused by bacterial infections have been reported for over 300 years [2]
We have revealed the relationship between immune function and the chemical structure of Gram-negative bacterial cell surface components, such as LPS and its active principle glycolipid lipid A
TLR4, and these interactions induced the dimerization of the TLR4/MD-2 complex, act cause TLR4/MD-2 dimerization, and all acyl chains are accommodated in the pocket of vating the innate immune response
Summary
The immunomodulatory effects triggered by bacteria have long been identified [1]. Tumor burden decrease and regression caused by bacterial infections have been reported for over 300 years [2]. Salmonella typhimurium and Mycobacterium tuberculosis were confirmed in 1916 and 1924, respectively. These immunostimulatory effects are widely known as the innate immune system. Innate immunity is stimulated via various innate immune receptors in multicellular organisms by recognizing the molecular pattern of pathogens. Most bacteria-derived innate immune stimulators exhibit inflammatory effects and toxicity. Regulating and attenuating the toxicity of innate immune stimulators is essential for their application as adjuvants. We have revealed the relationship between immune function and the chemical structure of Gram-negative bacterial cell surface components, such as LPS and its active principle glycolipid lipid A. Molecules 2021, 26, 6294 negative bacterial cell surface components, such as LPS and its active principle glycolipid
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
