The Sea Star Invertebrate Primitive Antibody (IPA):Rosetting And PFC (Plaque-Forming Cell). Anti-SRBC Antibodies

Cell-Mediated and Humoral Immune Responses in the Sea-Star Asterias Rubens (Echinoderm): Notion of Invertebrate Primitive Antibody

Appropriate conditions for the plaque forming cell (PFC) assay in rats and effects of cyclophosphamide on PFC response.

The appropriate conditions for the plaque forming cell (PFC) assay using rat splenocytes were determined and effects of cyclophosphamide on PFC response were investigated using these conditions. The number of PFCs produced by immunization with a suspension of sheep red blood cells (SRBCs) was higher with i.v. injection than with i.p. injection. Subcutaneous injection of the suspension did not p...

Mice Immunized with IgG Anti-Sheep Red Blood Cells (SRBC) Together With SRBC Have a Suppressed Anti-SRBC Antibody Response but Generate Germinal Centers and Anti-IgG Antibodies in Response to the Passively Administered IgG

Antigen-specific IgG antibodies, passively administered together with large particulate antigens such as erythrocytes, can completely suppress the antigen-specific antibody response. The mechanism behind has been elusive. Herein, we made the surprising observation that mice immunized with IgG anti-sheep red blood cells (SRBC) and SRBC, in spite of a severely suppressed anti-SRBC response, have ...

Immune Responses in Vitro

The effects of hyperimmune anti-sheep erythrocyte (SRBC) antibody on the plaque-forming cell (PFC) response to SRBC by mouse spleen cells in vitro were studied. Anti-SRBC antibody specifically suppressed the PFC response against SRBC. The degree of suppression was directly related to the amount of antibody added and was overcome by large amounts of antigen. Suppressive activity was absorbed fro...

Suppression of Memory by Passive Immunization Late in the Primary Response

The acquisition of a capacity to respond well to sheep erythrocytes in the presence of anti-SRBC antibody was taken as an indication of the presence of immunological memory. By the use of passive immunization, both the primary IgG plaque-forming cell response and the establishment of memory were abolished, despite occurrence of a full peak IgM PFC response. Evidence for regarding the aquisition...