Rhodobacter azotoformans LPS (RAP99-LPS) Is a TLR4 Agonist That Inhibits Lung Metastasis and Enhances TLR3-Mediated Chemokine Expression.

Frontiers in Immunology
Kaoru MurakamiMasaaki Murakami

Abstract

The lipopolysaccharides (LPSs) of Rhodobacter are reported to be TLR4 antagonists. Accordingly, the extract of Rhodobacter azotoformans (RAP99) is used as a health supplement for humans and animals in Japan to regulate immune responses in vivo. We previously analyzed the LPS structure of RAP99 (RAP99-LPS) and found it is different from that of E. coli-LPS but similar to lipid A from Rhodobacter sphaeroides (RSLA), a known antagonist of TLR4, with both having three C14 fatty acyl groups, two C10 fatty acyl groups, and two phosphates. Here we show that RAP99-LPS has an immune stimulatory activity and acts as a TLR4 agonist. Pretreatment of RAP99-LPS suppressed E. coli-LPS-mediated weight loss, suggesting it is an antagonist against E. coli-LPS like other LPS isolated from Rhodobacter. However, injections of RAP99-LPS caused splenomegaly and increased immune cell numbers in C57BL/6 mice but not in C3H/HeJ mice, suggesting that RAP99-LPS stimulates immune cells via TLR4. Consistently, RAP99-LPS suppressed the lung metastasis of B16F1 tumor cells and enhanced the expression of TLR3-mediated chemokines. These results suggest that RAP99-LPS is a TLR4 agonist that enhances the activation status of the immune system to promote anti-vira...Continue Reading

References

Apr 7, 1995·Science·W J ChristM A Mullarkey
Mar 1, 2000·Proceedings of the National Academy of Sciences of the United States of America·S KimW M Yokoyama
Mar 22, 2000·The Journal of Immunology : Official Journal of the American Association of Immunologists·F NomuraS Akira
May 12, 2000·European Journal of Biochemistry·U SeydelK Brandenburg
Feb 27, 2003·The Journal of Pharmacology and Experimental Therapeutics·Maureen MullarkeyDaniel P Rossignol
Mar 1, 2005·Cytokine & Growth Factor Reviews·Ganes C Sen, Saumendra N Sarkar
Mar 15, 2005·Journal of Neuroinflammation·Nikunj S PatelMichael J Mullan
Feb 12, 2008·Advanced Drug Delivery Reviews·Misako Matsumoto, Tsukasa Seya
Feb 9, 2011·The Journal of Immunology : Official Journal of the American Association of Immunologists·Yaron CarmiRon N Apte
Jul 13, 2012·The Journal of Immunology : Official Journal of the American Association of Immunologists·Gayathri SrinivasanMatam Vijay-Kumar
Feb 26, 2013·Cell Reports·Masaaki MurakamiToshio Hirano
Jul 26, 2014·Nature Reviews. Immunology·Nicholas J GayClare E Bryant
Sep 7, 2017·Scientific Reports·Lydia Asrat HaileDaniela Verthelyi
Jan 19, 2019·Carbohydrate Research·Yoshimi KanieOsamu Kanie
Apr 24, 2020·Immunity·Toshio Hirano, Masaaki Murakami

❮ Previous
Next ❯

Software Mentioned

excitonix

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.