abnormal circulating interferon level MPheno.ontology MP:0008548 anomaly in the amount in the blood of proteins secreted by vertebrate cells in response to a wide variety of inducers; they confer resistance against many different viruses, inhibit proliferation of normal and malignant cells, impede multiplication of intracellular parasites, enhance macrophage and granulocyte phagocytosis, augment natural killer cell activity, and show several other immunomodulatory functions abnormal circulating IFN level abnormal interferon level abnormal circulating cytokine level