Complement dependence of localisation of aggregated IgG in germinal centres

In vivo decomplementation of mice with cobra factor completely prevented trapping of aggregated human IgG within splenic germinal centres. Observations of the intrasplenic position of the aggregated material within 8 hr of its injection into normal and decomplemented mice suggest that the early phase of localisation in germinal centres depends on binding to lymphocyte C3 receptors.