THE USE OF ANTIBODY-SECRETING CELL PROBES TO REVEAL TISSUE-RESTRICTEDIMMUNE-RESPONSES DURING INFECTION

Antibody secreting cell probes (ASC-probes) were generated from the he patic lymph node (HLN), mesenteric lymph node (MLN) and spleen of rats after infection with the liver fluke, Fasciola hepatica, and used to probe Western blots of parasite antigens. In chronic primary infection s, parasite-specific antibodies were only detected in ASC-probes deriv ed from HLN. Seven days after a secondary infection, a restricted resp onse was detected in ASC-probes from the MLN, directed predominantly a gainst an antigen specific to the newly excysted juvenile (NEJ) stage. This NEJ-specific antigen was only recognized by HLN if the second in fection was not rejected and the challenge flukes reached the liver. M easurement of the immunoglobulin levels present in the ASC-probes show ed significant elevation only in lymph nodes draining sites of recent infection. In addition, when the isotype profiles were determined in A SC-probes derived from different lymph nodes, it was observed that the y showed different isotype preferences, in particular IgA for the MLN, IgE for HLN and IgM for spleen. These results show that discrete and independent immune responses occur in different body compartments of a rat against different stages of a parasite.