Primed Activation of Macrophages by Oral Administration of Lipopolysaccharide Derived from Pantoea agglomerans.
OBJECTIVE
Bacterial lipopolysaccharide (LPS) is involved in the activation of the innate immune responses on monocytes/macrophages in vitro, and by intravenous injection. Although small quantities of LPS are usually found in traditional Chinese medicines, vegetables and fruits, the mode of action of orally administered LPS is still unclear.


METHODS
LPS derived from Pantoea agglomerans (LPSp) was orally administered to C3H/HeN or C3H/HeJ mice ad libitum.


RESULTS
The LPSp treatment enhanced phagocytosis by resident peritoneal macrophages of C3H/HeN mice but not of C3H/HeJ mice. This activation can be defined as primed activation because no augmentation of inflammatory cytokines production was detected. LPSp in peritoneal fluid was detected and successfully quantified. Moreover, the LPSp reduced the expression of avian reticuloendotheliosis viral oncogene-related B (RelB) in the macrophages without degradation of nuclear factor of kappa light polypeptide gene enhancer in B-cell inhibitor, alpha (IκBα).


CONCLUSIONS
Orally administered LPSp can reach the peritoneum, and enhance phagocytosis via Toll-like receptor 4 signaling pathway in resident peritoneal macrophages.
Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Kagawa, Japan Control of Innate Immunity, Technology Research Association, Kagawa, Japan pxs07205@nifty.ne.jp.
Hiroyuki
H
Inagawa
Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Yutaro
Y
Kobayashi
Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Chie
C
Kohchi
Control of Innate Immunity, Technology Research Association, Kagawa, Japan.
Ran
R
Zhang
Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Kagawa, Japan.
Yasuhiro
Y
Shibasaki
Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Kagawa, Japan Control of Innate Immunity, Technology Research Association, Kagawa, Japan Research Institute for Healthy Living, Niigata University of Pharmacy and Applied Life Sciences, Niigata, Japan.
Gen-Ichiro
G
Soma
D000284:Administration, Oral; D000818:Animals; D039481:CD11b Antigen / Q000276:immunology / Q000378:metabolism; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D005434:Flow Cytometry; D015151:Immunoblotting; D018836:Inflammation Mediators / Q000276:immunology / Q000378:metabolism; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000276:immunology / Q000494:pharmacology*; D008262:Macrophage Activation / Q000187:drug effects* / Q000276:immunology; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000382:microbiology; D008297:Male; D008809:Mice, Inbred C3H; D020636:Pantoea / Q000737:chemistry*; D010587:Phagocytosis / Q000187:drug effects / Q000276:immunology; D051197:Toll-Like Receptor 4 / Q000276:immunology / Q000378:metabolism; D051841:Transcription Factor RelB / Q000276:immunology / Q000378:metabolism
D039481:CD11b Antigen; D016207:Cytokines; D018836:Inflammation Mediators; D008070:Lipopolysaccharides; C497594:Relb protein, mouse; C493487:Tlr4 protein, mouse; D051197:Toll-Like Receptor 4; D051841:Transcription Factor RelB
LPS; Pantoea agglomerans; macrophage; oral administration; priming