Animals
BALB/c mice were purchased from Charles River (Margate, Kent, UK). C57BL/6 and Ifnar1–/– (C57BL/6 background)20 mice were bred in-house at the University of Edinburgh. Eight – 12 week old mice were infected by oral gavage with 200 stage 3 H. polygyrus larvae. Some animals were administered 20 µg of anti-CCR2 antibody (MC-21, gift M. Mack) by intra-peritoneal injection seven and nine days later. Other animals were given 2x106 enriched bone marrow monocytes by intravenous injection. Some animals were infected with RSV (105plaque forming units) intranasally ten days after H. polygyrusinfection. After monocyte transfer RSV was administered 30 minutes later. All procedures were approved by local ethical review committee and the UK Home Office.