INTERFERONS (IFN)

INTERFERONS (IFN):

• GENERAL PROPERTIES:
• Is secreted out of host cell, usually found in a dimer or multimeric form.
• IFN goes out, binds to specific receptors on neighboring cells, and changes their transcription in such a way as to give them anti-viral properties.
• ds-RNA and LPS are both good inducers of IFN.
• FUNCTION: Suggested mechanism of action involves RNA endonuclease activity, and induction of transcription of new genes.
• IFN also prevents DNA synthesis and thus inhibits cell growth.
• ANTI-TUMOR: IFN's generally have some anti-tumor activity, particularly on leukemias and lymphomas. They induce the production of HLA antigens on tumor cells, thereby allowing the immune system to recognize the tumor cell.
• RESISTANT: CMV and VZV are resistant to IFN. Other viruses are mostly susceptible.
• INTERFERON-alpha: Produced by leukocytes.
• Receptor gene for IFN-alpha is on Chrom #21
• FNXN: Has been approved as a treatment for rare B-Cell Hairy Leukemia.
• INTERFERON-beta: Produced by fibroblasts.
• Receptor gene for IFN-beta is on Chrom #21
• INTERFERON-gamma: Produced by (1) unsensitized lymphoid cells, or (2) sensitized T_H1 cells.
• It is stronger than other two in its antiviral properties.
• Receptor gene for IFN-gamma is on Chrom #6