The identification of soluble adult antigen on the tegumental surface of juvenile Fasciola hepatica.

An antiserum was raised in rabbits against a soluble extract of fresh homogenized adult Fasciola hepatica of rat origin and was then absorbed with rat and mouse tissue antigens. This antiserum reacted specifically with the surface coat of adult flukes, of both rat and mouse origin, by indirect immunofluorescence to show the detail of surface spines. When tested against juvenile stages recovered from mice the reaction was positive with all but the earliest hepatic parenchyma stages. No reaction was present on the tegumental surface of newly excysted juveniles or stages 1 or 2 days post-infection (p.i.) whether recovered from the peritoneal cavity or the hepatic parenchyma.