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 TH1 cells.

  • It is stronger than other two in its antiviral properties.

  • Receptor gene for IFN-gamma is on Chrom #6

Category: Microbiology Notes