title: Effect of metabolic state on agglutination of human erythrocytes by concanavalin A.
abstract: Intact freshly drawn or stored human erythrocytes, which show little agglutination by concanavalin A, become agglutinable by this lectin in the presence of adenosine. alpha-Methylglucose (10 mM) completely inhibits this agglutination. The concanavalin A agglutination shows no sensitivity to vinblastine or cytochalasin B. Resealed membranes preparaed with ATP in lysing and resealing medium give modest agglutinability, while the presence of adenosine in both the lysing and the resealing medium results in a substantial agglutinability of the resealed membranes. Mild trypsin treatment of the erythrocytes causes an enhanced sensitivity to adenosine activation of the concanavalin A agglutination, while extensive trypsin treatment produced highly agglutinable erythrocytes that shown no response to the presence of adenosine in the lectin solution. The extensively treated erythrocytes also show concanavalin A agglutination at temperatures below 37 degrees C, under conditions in which intact or moderately treated erythrocytes do not agglutinate, with or without adenosine present. Results suggest that the adenosine activation of concanavalin A agglutination of intact human erythrocytes is mediated through a metabolic conversion of adenosine to a rapidly turned over metabolite which participates directly in the activation of agglutination. The agglutinability does not appear to depend on whole cell ATP levels, but may involve a particular pool of ATP. The effect of variation of cellular metabolic state and the response of particular systems involved in lectin-mediated agglutinability to cellular metabolism seem to be worth consideration in explaining the frequently large differences in agglutinability of und in cells in different biological states, such as those encountered in normal and transformed cells.
mesh_terms: D000241:Adenosine / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects; D003208:Concanavalin A / Q000494:pharmacology*; D004903:Erythrocyte Aggregation / Q000187:drug effects; D004912:Erythrocytes / Q000187:drug effects; D006801:Humans; D007700:Kinetics; D013696:Temperature; D014357:Trypsin
chemical_list: D003208:Concanavalin A; D000255:Adenosine Triphosphate; D014357:Trypsin; D000241:Adenosine