Analysis of the intradermal response against a soluble cercarial antigenic preparation from Schistosoma mansoni

Intradermal testing was performed with a soluble cercarial antigenic preparation (CAP) from Schistosoma mansoni cercariae in CBA/J mice multiply infected with S. mansoni or sensitized with CAP. Both an early (5-h) response and a late (24- to 48-h) reaction to CAP, as measured by increase in dermal thickness, was elicited after injection of antigen into the ears of either multiply infected (3X-75) or CAP-sensitized (CAP/complete Freund adjuvant [CFA]) mice. Histopathological examination showed that the early response was primarily vascular in nature and involved a polymorphonuclear cell infiltrate in and around dilated capillaries. The late reaction to CAP consisted of a perivascular cellular infiltrate of polymorphonuclear and mononuclear cell types. Passive transfer of 3X-75-infected or CAP/CFA-sensitized serum (0.4 ml) to normal mice conveyed the ability to mount an early (5-h) response to CAP which was marked histopathologically by a prominent polymorphonuclear cell infiltrate. The majority of the responsiveness in normal mice after administration of lymph node cells (40 X 10(6)) from multiply infected or CAP/CFA-sensitized mice was observed 24 to 48 h after injection of CAP and was mononuclear in nature.