TY - JOUR
T1 - Extracellular ATP does not induce P2X7 receptor-dependent responses in cultured renal- and liver-derived swine macrophages
AU - Takenouchi, Takato
AU - Suzuki, Shunichi
AU - Shinkai, Hiroki
AU - Tsukimoto, Mitsutoshi
AU - Sato, Mitsuru
AU - Uenishi, Hirohide
AU - Kitani, Hiroshi
N1 - Funding Information:
The authors would like to thank the staff of the Swine Management Section of the National Institute of Livestock and Grassland Science for taking care of the pigs. This study was supported by a grant from the Ministry of Agriculture, Forestry and Fisheries of Japan (Genomic-based Technology for Agricultural Improvement, AGB-1004 ) and a Grant-in-Aid for Scientific Research (Category C: Grant# 25450521 ) from the Japan Society for the Promotion of Science (JSPS).
PY - 2014/10
Y1 - 2014/10
N2 - The P2X7 receptor (P2X7R) is an ATP-gated cation channel that is abundantly expressed in monocytes/macrophages. P2X7R activation by ATP results in various cellular responses including Ca2+ influx, membrane pore formation, and cytokine secretion. Since P2X7R has low affinity for ATP, high concentrations of ATP (in the mM range) are generally required to activate this receptor in vitro. Functional expression of P2X7R has been detected in monocytes/macrophages obtained from different animal species including humans, rodents, dogs, and bovines, but so far it has not been detected in swine (Sus scrofa). In this study, we investigated the expression and functions of P2X7R in swine macrophages, which were isolated from mixed primary cultures of swine kidney or liver tissue. The P2X7R mRNA and protein expression observed in the swine macrophages was comparable to that seen in a c-myc-immortalized mouse kidney-derived clonal macrophage cell line (KM-1). However, extracellular ATP did not induce P2X7R-dependent sustained Ca2+ influx, membrane pore formation, or the secretion of the bioactive cytokine interleukin-1β in the swine macrophages, whereas these responses were clearly observed in the mouse KM-1 cells after stimulation with millimolar concentrations of ATP as a positive control. These findings suggest that the ATP/P2X7R pathway is impaired in swine macrophages at least in the culture conditions used in the present study.
AB - The P2X7 receptor (P2X7R) is an ATP-gated cation channel that is abundantly expressed in monocytes/macrophages. P2X7R activation by ATP results in various cellular responses including Ca2+ influx, membrane pore formation, and cytokine secretion. Since P2X7R has low affinity for ATP, high concentrations of ATP (in the mM range) are generally required to activate this receptor in vitro. Functional expression of P2X7R has been detected in monocytes/macrophages obtained from different animal species including humans, rodents, dogs, and bovines, but so far it has not been detected in swine (Sus scrofa). In this study, we investigated the expression and functions of P2X7R in swine macrophages, which were isolated from mixed primary cultures of swine kidney or liver tissue. The P2X7R mRNA and protein expression observed in the swine macrophages was comparable to that seen in a c-myc-immortalized mouse kidney-derived clonal macrophage cell line (KM-1). However, extracellular ATP did not induce P2X7R-dependent sustained Ca2+ influx, membrane pore formation, or the secretion of the bioactive cytokine interleukin-1β in the swine macrophages, whereas these responses were clearly observed in the mouse KM-1 cells after stimulation with millimolar concentrations of ATP as a positive control. These findings suggest that the ATP/P2X7R pathway is impaired in swine macrophages at least in the culture conditions used in the present study.
KW - Interleukin-1β
KW - Membrane pore formation
KW - P2X7 receptor
KW - Swine macrophages
UR - https://www.scopus.com/pages/publications/84905686818
U2 - 10.1016/j.rinim.2014.07.002
DO - 10.1016/j.rinim.2014.07.002
M3 - Article
AN - SCOPUS:84905686818
SN - 2211-2839
VL - 4
SP - 62
EP - 67
JO - Results in Immunology
JF - Results in Immunology
IS - 1
ER -