Acceleration of thrombosis and hemolysis by fibrinolysis inhibiting factor and suppression by Ia antigen expressed on T cells in partially hepatectomized Lewis rats

Partial hepatectomy (PH) of a left lateral lobe was performed on 45 Lewis rats 6.5-8.0 weeks old. Splenectomy, the injection of a fibrinolysis inhibiting (F1) factor (Gly-Pro-Arg-Pro) and both treatments were combined with the PH in 10, 11 and 9 rats, respectively. Among them, 4 males became weak with marked atrophic thymus before the 46th day after PH. All these males had massive pulmonary necrosis accompanied by platelet-rich emboli. Erythrocyte rosette formation was recognized in the mesenteric lymph nodes (MLN) of all 4 rats. The rosette erythrocytes reacted to anti-macrophage antibodies. FI factor-induced acute immune hemolysis occurred 5-9 days after PH in the 2 of the FI factor-injected and splenectomized males. Mildly to moderately atrophic thymuses were found in almost all the rats followed for 156-177 days after PH. T lymphocytes with cytoplasmic dense polysomes and desquamating endothelial cells with phagocytic erythrocytes were observed in the thymic electron micrograph of the FI factor-injected female. Positive D-D dimers were measured in the plasma of 7 rats. Increased peripheral reticulocytes (7.0 +/- 0.4%) were recognized in the males 156 days after single PH but not in the females. Ten of the 24 females and 3 of the 16 males showed an increase of peripheral Ia+ T cells to 20-30%. As well as acute pulmonary emboli, autoimmune hemolysis was induced more actively after PH in the males with CD5+ T cells that expressed the Ia antigen weakly.