FC-RECEPTOR-BEARING MACROPHAGES ISOLATED FROM HYPERSENSITIVITY AND FOREIGN-BODY GRANULOMAS - DELINEATION OF MACROPHAGE DYNAMICS, FC RECEPTOR DENSITY-AVIDITY AND SPECIFICITY

  • 1 January 1979
    • journal article
    • research article
    • Vol. 96  (2) , 457-+
Abstract
Foreign-body and delayed hypersensitivity granulomas were induced in mice and the dynamics of macrophages isolated from dispersed, 1-4 wk old lesions was delineated. The size and histologic complexity of the lesions increased as shown: adjuvant > schistosome egg > methylated bovine serum albumin > bead. Esterase staining, spreading on glass and the percentage of Fc-receptor-bearing macrophages present in the various granulomas reflected the same gradient. The Fc receptors were examined by rosetting with rabbit antibody-SRBC [sheep red blood cell] complex (EA). Whereas more than 90% of the population of macrophages of the dermal adjuvant granuloma contained undiminished numbers of receptor-bearing macrophages throughout the 4 wk, the percentage of macrophages that displayed receptors in pulmonary foreign body (40%) and delayed hypersensitivity granulomas (70%) peaked at 1 wk and subsequently declined. The EA rosetting ot the foreign body and delayed hyeprsensitivity granuloma macrophages was strongly inhibited by monomeric Ig[immunoglobulin]G2a-specific and weakly by aggregated IgG2b-specific mouse myeloma proteins. Macrophages of the delayed hypersensitivity granulomas rosetted in higher precentages with SRBC couple with monomeric IgG2a than with those coupled with aggregated IgG2b-SRCB. Rosetting with monomeric IgG2a-SRBC or aggregated IgG2b-SRBC could not be cross-inhibited by the myeloma proteins. The monomeric IgG2a-SRBC and aggregated IgG2b-SRBC complexes were readily phagocytized. Trypsin treatment of the macrophages inhibited rosetting with EA or myeloma protein-coupled SRBC. The display of Fc receptors on the granuloma macrophages seems related to the etiology of the lesion and the intensity and duration of the inflammatory reaction.