Glycoconjugate Journal

, Volume 25, Issue 5, pp 427–439

TLR-independent induction of human monocyte IL-1 by phosphoglycolipids from thermophilic bacteria

Authors

  • Feng-Ling Yang
    • Institute of Biological ChemistryAcademia Sinica
  • Kuo-Feng Hua
    • Department of Biotechnology and Laboratory Science in MedicineNational Yang-Ming University
  • Yu-Liang Yang
    • Institute of Biological ChemistryAcademia Sinica
  • Wei Zou
    • Institute for Biological SciencesNational Research Council of Canada
  • Yen-Po Chen
    • Agricultural Biotechnology Research CenterAcademia Sinica
  • Shu-Mei Liang
    • Agricultural Biotechnology Research CenterAcademia Sinica
    • Department of Biotechnology and Laboratory Science in MedicineNational Yang-Ming University
    • Department of Education and ResearchTaipei City Hospital
    • Institute of Biological ChemistryAcademia Sinica
Article

DOI: 10.1007/s10719-007-9088-2

Cite this article as:
Yang, F., Hua, K., Yang, Y. et al. Glycoconj J (2008) 25: 427. doi:10.1007/s10719-007-9088-2

Abstract

The structures of phosphoglycolipids PGL1 and PGL2 from the thermophilic bacteria Meiothermus taiwanensis, Meiothermus ruber, Thermus thermophilus, and Thermus oshimai are determined recently (Yang et al. in J Lipid Res. 47:1823–1932, 2006). These bacteria belong to Gram-negative bacteria that do not contain lipopolysaccharide, but high amounts of phosphoglycolipids and glycoglycerolipids. Here we show that PGL1/PGL2 mixture (PGL1: PGL2 = 10:1 ~ 10:2) from M. taiwanensis and T. oshimai, but not T. thermophilus and M. ruber, up-regulate interleukin-1β (IL-1β) production in human THP-1 monocytes and blood-isolated primary monocytes. PGL2 was purified after phospholipase A2 hydrolysis of PGL1 in the PGL1/PGL2 mixture followed by column chromatography. PGL2 did not induce proIL-1 production, even, partially (35–40%) inhibited PGL1-mediated proIL-1 production, showing that PGL1 is the main inducer of proIL-1 production in PGL1/PGL2 mixture. The production of proIL-1 stimulated by phosphoglycolipids was strongly inhibited by specific PKC-α, MEK1/2, and JNK inhibitors, but not by p38-specific inhibitor. The intracellular calcium influx was involved in phosphoglycolipids-mediated proIL-1 production. Using blocking antibody and Toll-like receptor (TLR)-linked NF-κB luciferase assays, we found that the cellular receptor(s) for phosphoglycolipids on proIL-1 production was TLR-independent. Further, phosphoglycolipids isolated from T. thermophilus and M. ruber did not induce proIL-1 production, even though T. thermophilus possess more PGL1 than PGL2 (6:4). Specially, the fatty acid composition of phosphoglycolipids from both T. thermophilus and M. ruber consists of a low percentage of C15 (<10%) and a high percentage of C17 (>75%). It suggests, the C15 percentage of PGL may play a critical role in PGL-mediated proIL-1 induction.

Keywords

PhosphoglycolipidsThermophilic bacteriaImmunomodulators

Copyright information

© Springer Science+Business Media, LLC 2007