The localization of immunoglobulin and immune complexes in lymphoid tissue.

Abstract

Aggregated and monomeric forms of human γ-globulin (HGG) were prepared by heating at 63°, ultracentrifugation and subsequent separation according to solubility in 0.62 M sodium sulphate. These two forms were injected intradermally into guinea-pigs' ears and their distribution in the draining auricular nodes determined at different times following injection by staining cryostat sections with fluorescein labelled anti-HGG. Monomeric HGG showed no precise localization; aggregated HGG localized rapidly in the phagocytic macrophages of the sinuses and medulla and after a few hours' delay in the germinal centres in a dendritic pattern, the latter persisting for up to 4 weeks. With doses of less than 10 μg, aggregated HGG was not seen in the medulla but germinal centre staining was readily visible, possibly due to a concentrating effect. Prior injection of a large dose of monomer either locally or systemically did not alter the pattern of staining produced by subsequent injection of aggregated HGG.