Detection of lymphokines and lymphokine receptors in pulmonary sarcoidosis. Immunohistologic evidence that inflammatory macrophages express IL-2 receptors.
In an investigation of the immunopathogenesis of sarcoidosis, the authors undertook the tissue localization of those lymphokines and lymphokine receptors which are known to play a central role in T-cell and macrophage activation. Using monoclonal antibodies and an ABC immunoperoxidase technique. They determined the distribution of gamma interferon (IFN-g), interleukin-2 (IL-2), and corresponding IL-2 receptors (IL-2R), plus T cells and T cell subsets, B cells, and macrophages within thoracic lymph nodes and lung specimens of 9 patients with active pulmonary sarcoidosis. Epithelioid and multinucleate giant cells within sarcoid granulomas of all specimens showed membrane labeling for IL-2R and IFN-g, in addition to IL-2, suggesting that these cells indeed express functional IL-2 receptors. Infiltrating T cells, largely T4+, were also IL-2R+, and many showed IL-2 and IFN-g labeling. By comparison, macrophages within sections of normal lung or lymph node failed to stain for IL-2, IL-2R, or IFN-g. These immunohistologic studies extend recent in vitro observations by these authors and others that normal human blood monocytes and alveolar macrophages are induced by IFN-g or IL-2 to express functional membrane-bound IL-2 receptors. The in vivo expression of IL-2R by mononuclear phagocytes in pulmonary sarcoidosis is demonstrated, and a new role is suggested for T-cell-derived lymphokines in macrophage activation.
Hancock
W W
WW
Kobzik
L
L
Colby
A J
AJ
O'Hara
C J
CJ
Cooper
A G
AG
Godleski
J J
JJ
D000911:Antibodies, Monoclonal; D006651:Histocytochemistry; D006801:Humans; D007124:Immunoenzyme Techniques; D007249:Inflammation / Q000276:immunology; D007371:Interferon-gamma / Q000032:analysis; D007376:Interleukin-2 / Q000032:analysis; D008168:Lung / Q000276:immunology; D008171:Lung Diseases / Q000276:immunology*; D008198:Lymph Nodes / Q000276:immunology; D008222:Lymphokines / Q000032:analysis*; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology*; D011971:Receptors, Immunologic / Q000032:analysis*; D012507:Sarcoidosis / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
D000911:Antibodies, Monoclonal; D007376:Interleukin-2; D008222:Lymphokines; D011971:Receptors, Immunologic; D007371:Interferon-gamma