1.   In recent years several strategies have been tested to enhance the efficacy of interferon therapy for chronic hepatitis B.

2.   The single gene that showed the most increased activity encodes gamma interferon, an immune-system activator.

3.   Andersen said the scientists also tested the samples for the response to gamma interferon, a natural protein that enhances immunity.

4.   In a telephone interview, Rossi said he does not know whether gamma interferon is present in the brain to help activate microglia.

5.   On Monday, Susanna hopes to get her first dose of the drug, gamma interferon, which will stimulate her immune system.

6.   The drug, gamma interferon, produced by the biotech company Genentech, stimulates the immune system.