Expression of a functional human type I interferon receptor in hamster cells: application of functional yeast...

Area of Science:

• Immunology
• Molecular Biology
• Genetics

Background:

• The human Type I interferon (IFN) receptor is crucial for cellular defense against viruses and for immune regulation.
• Previous studies identified a cDNA for a subunit of the Type I IFN receptor, but it did not fully explain the receptor complex's function.

Purpose of the Study:

• To identify and characterize the complete gene set required for a functional Type I human interferon receptor complex.
• To investigate the role of specific human chromosome segments in mediating cellular responses to Type I interferons.

Main Methods:

• Introduction of a yeast artificial chromosome (YAC) containing a segment of human chromosome 21 into Chinese hamster ovary (CHO) cells.
• Assessing cellular responses by measuring the induction of class I MHC antigens.
• Evaluating protection against viral infections (encephalomyocarditis virus and vesicular stomatitis virus).
• Measuring high-affinity binding of various Type I human interferons.

Main Results:

• The YAC-containing CHO cells exhibited significantly enhanced responses to multiple Type I interferons, including Hu-IFN-alpha A, Hu-IFN-alpha B2, Hu-IFN-omega, and Hu-IFN-beta.
• These enhanced responses included increased induction of class I MHC antigens and improved protection against viral infections.
• The modified cells demonstrated specific high-affinity binding for these Type I interferons, confirming receptor complex functionality.

Conclusions:

• A yeast artificial chromosome (YAC) containing a specific human chromosome 21 segment harbors all necessary genes to reconstitute a biologically active Type I human interferon receptor complex.
• This finding provides a comprehensive understanding of the genetic basis for Type I interferon signaling.
• The reconstituted receptor complex is fully functional, mediating enhanced antiviral and immunomodulatory responses.