PROCOAGULANT ACTIVITY OF LYMPHOCYTE-MACROPHAGE POPULATIONS IN RABBITS - SELECTIVE INCREASES IN MARROW, BLOOD, AND SPLEEN-CELLS DURING SHWARTZMAN REACTIONS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 61  (4) , 712-717
Abstract
The present experiments examine leukocyte procoagulant activity using mononuclear cell populations purified or enriched from rabbit bone marrow, blood, spleen, lymph node, thymus and pulmonary alveoli. Cells from these 6 sites, obtained from control and endotoxemic animals and assayed without an intermediate culture step, were found to have procoagulant activity identified as tissue factor. Under control conditions, tissue factor activity was found to be at low levels in marrow and blood populations compared to median activities 3- and 11-fold higher in populations from spleen and lymph node, and 33- and 45-fold higher in thymus and alveolar populations. By contrast to respective controls, significantly increased amounts of tissue factor (35-, 15- and 12-fold at median levels) were found in marrow, blood and spleen populations from endotoxemic animals. The types of leukocytes in these latter 3 populations were morphologically and histochemically indistinguishable from respective controls, indicating that endotoxin induced increases of activity in cells with relatively low amounts under control conditions. Activity did not change significantly in lymph node, thymus, or alveolar populations after endotoxemia. Tissue factor apparently is present in a range of leukocyte populations not previously reported to have procoagulant activity. In addition, the finding of widespread gains of tissue factor in the marrow-blood-spleen pool due to endotoxemia provides new evidence supporting the importance of leukocyte procoagulants in Shwartzman-like reactions.