Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.14.99.3 (heme oxygenase)
 4,196 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of membrane-bound IgG present on the membrane of senescent erythrocytes in immune eliminations of aging red cells was investigated. Phagocytosis of populations of red blood cells (RBC) of different ages by autologous monocytes was assessed both by direct phagocytosis and by induction of microsomal heme oxygenase. Removal of IgG from older RBCs inhibited their phagocytosis; in contrast, preincubation of neuraminidase-treated young or in vitro aged RBCs with IgG eluted from old cells led to phagocytosis of RBCs treated by autologous monocytes. It was also found that the Fc portion of membrane-bound IgG is essential for the elimination of senescent cells; less than 15% of old heat-inactivated RBCs coated with F(ab)2 fragment of membrane-bound IgG were phagocytosed. In contrast, more than 50% of old heat-inactivated RBCs coated with heat-eluted IgG were phagocytosed by autologous monocytes. A possible mechanism of elimination of aged cells is discussed.
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PMID:Phagocytosis of senescent erythrocytes by autologous monocytes: requirement of membrane-specific autologous IgG for immune elimination of aging red blood cells. 668 42

It has been shown previously that autologous monocytes recognize and phagocytose aging self-erythrocytes in vitro. The recognition requires the presence of an autoantibody present in all normal serum. Herein a similar mechanism of recognition and immune elimination of senescent erythrocytes in vivo is reported. When autologous rabbit red blood cells (RBCs), aged either in vivo or neuraminidase-treated young, were reinjected into the animal, most of the old RBCs were trapped in the liver while the majority of the young cells lodged in the spleen. Following reinjection of aging RBCs, the activity of microsomal heme oxygenase enzyme of the liver tissue increased greater than fourfold, suggesting erythrophagocytosis activity of Kupffer cells.
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PMID:Immune elimination of autologous senescent erythrocytes by Kupffer cells in vivo. 668 79