Adenosine deaminase levels in blood type A patients with metastatic tumor

A lack of adenosine deaminase activity has been associated with severe combined immunodeficiency and decreased enzyme activity observed in acute lymphocytic leukemia. We have measured enzyme activity in lymphocytes, red blood cells, and plasma of patients with a variety of metastatic tumors. Patients with tumor had a significantly lower erythrocyte adenosine deaminase activity (p less than 0.025) and statistically higher enzyme activity in their lymphocytes (p less than 0.010) when compared with control plasmaphoresis donors. Interestingly, blood type A tumor patients showed a significant decrease in their erythrocyte enzyme concentration compared with blood group A controls (p less than 0.001) as well as a collective group of type B and O tumor patients (p less than 0.001). Type A patient lymphocyte adenosine deaminase activity was not increased and was not statistically different from control group A donors. Tumor patients with blood groups B and O considered collectively had a statistically significant increase in their lymphocyte enzyme concentration compared with group B and O controls (p less than 0.001).