The macrophage at the intersection of immunity and metabolism in obesity

Obesity is a worldwide pandemic representing one of the major challenges that societies face around the globe. Identifying the mechanisms involved in its development and propagation will help the development of preventative and therapeutic strategies that may help control its rising rates

Monocytic origin of foam cells in human atherosclerotic plaques.

Foam cells in 4 human atherosclerotic plaques reacted with 3 rat monoclonal antibodies directed against T.200 ('anti-leucocyte common' antibody), HLA-Class II molecules and macrophage cytoplasm, respectively. Smooth muscle cells did not react. The results support the view that foam cells are monocyte-derived macrophages

Immunohistological screening in the selection of monoclonal antibodies: the use of isotype-specific antiglobulins.

This paper describes the use of the immunoperoxidase technique for the screening of rat hybridoma culture supernatants on tissue sections. By combining the avidin-biotin system with mouse monoclonal antibodies specific to different rat immunoglobulin isotypes, it is possible to resolve the specificity patterns of complex mixtures of monoclonal antibodies from uncloned culture wells. This strategy is particularly useful in the derivation of monoclonal antibodies to cell surface antigens

Identification of macrophages and smooth muscle cells in human atherosclerosis using monoclonal antibodies.

Sections of human atherosclerotic plaques were stained by the indirect immunoperoxidase technique using three rat anti-human monoclonal antibodies: YAML 501.4 (anti-'leukocyte-common' (T200) antigen; YTH 8.18 (antimacrophage cytoplasm); and YPC 1/3 . 12 (anti-smooth muscle cell). The cells of diffuse intimal thickening were almost all smooth muscle cells but there were rare subendothelial macrophages. Focal lesions, in contrast, contained numerous macrophages as well as smooth muscle cells. Macrophage 'foam cells' were particularly numerous in fatty streaks and in advanced fibro-fatty plaques, but were less conspicuous in focal fibro-elastic lesions. The results confirm that macrophages are an important component of atherosclerotic plaques and suggest that they may have a significant role in atherogenesis in man

Identification of cells of the human mononuclear phagocyte system with rat monoclonal antibodies.

Five rat monoclonal antibodies (McAbs) to human macrophages are described: YTH 8.18, YTH 25.7, YTH 51.1, YTH 85.12.1, and YHB 65.5. These McAbs are divided into three groups, since YTH 8.18, YTH 51.1, and YHB 65.5 are thought to identify the same antigen. These McAbs react with some bone marrow blast cells, granulocytes, and different percentages of peripheral blood monocytes. When studied on different body tissues, they were found to identify all members of the mononuclear phagocyte system (MPS), except Langerhans cells of skin and epithelium and in the case of one group (YTH 8.18/YTH 51.1/YHB 65.5) osteoclasts. In nine reactive lymph nodes the anti macrophage McAbs identified germinal centre macrophages, sinus macrophages, and interdigitating cells, but not dendritic reticulum cells. They also identified epithelioid macrophages and Langhans-type multi-nucleated giant cells in lymph nodes involved in granulomatous lesions (sarcoidosis and toxoplasmosis). In 24 cases of non-Hodgkin's lymphoma, the antimacrophage McAbs identified reactive macrophages in cases of B- or T-lymphocyte origin, whereas in three selected cases of true histiocytic lymphoma all the McAbs were found to be reactive with the vast majority of neoplastic macrophages as they were with the cells of a neoplastic macrophage line (U937). The possible use of these McAbs in the identification of benign and malignant macrophages in different systems is discussed