This two-part study aims to evaluate a new biologic agent for treatment of B cell non-Hodgkin lymphomas. The drug consists of two immune system proteins linked together through genetic engineering – an antibody that attaches to the surface of cancer cells, and interferon-alpha, which inhibits the growth of malignant cells. This antibody-interferon fusion thus targets the toxic protein directly to tumors. This treatment is highly effective against lymphoma in mice, and we now plan to: 1) Test the antibody-interferon fusion against human lymphoma cells in the laboratory, and 2) Design a Phase I clinical trial to begin testing in humans with lymphoma.