RT Journal Article SR Electronic T1 Haematopoietic stem cell recruitment to injured murine liver sinusoids depends on α4β1 integrin/VCAM-1 interactions JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 79 OP 87 DO 10.1136/gut.2008.168054 VO 59 IS 01 A1 D P J Kavanagh A1 L E Durant A1 H A Crosby A1 P F Lalor A1 J Frampton A1 D H Adams A1 N Kalia YR 2010 UL http://gut.bmj.com/content/59/01/79.abstract AB Objective: Evidence suggests haematopoietic stem cells (HSCs) can migrate to injured liver and influence tissue repair. However, mechanisms governing HSC recruitment to injured hepatic microcirculation are poorly understood. These were investigated in vivo following hepatic ischaemia–reperfusion (IR) injury and in vitro using flow-based adhesion assays.Design: Partial IR was induced in anaesthetised WT or PECAM-1−/− mice for 90 min. Recruitment of systemically administered HSCs was monitored and effects of function blocking antibodies against α4β1 integrin, CD18, CD44, PECAM-1 or VCAM-1 investigated. The kinetics and molecular events governing adhesion to murine cardiac endothelial cells in vitro were also determined. Effects of conditioned media from IR injured liver on HSC adhesion molecule expression was determined by FACS.Results: Administered HSCs homed predominantly to lungs rather than liver, highlighting a potential therapeutic hurdle. Hepatic HSC recruitment following IR injury was inhibited by anti-α4β1 and anti-VCAM-1 antibodies. A role for α4β1 was also confirmed using flow-based adhesion assays. Incubating HSCs with conditioned media from IR injured liver increased α4β1 expression. CD18, CD44 and PECAM-1 were not involved in recruitment.Conclusions: This novel study demonstrates that the α4β1/VCAM-1 pathway mediates HSC recruitment to injured liver. Manipulating this pathway may enhance delivery of HSCs to the liver.