Transfection as an Approach to Understanding Membrane Glycoproteins
Gene transfection has much to contribute to our understanding of membrane glycoproteins. The technique is in principle simple: it consists of the transfer of a single gene from one cell to another, using the method of DNA recombination in plasmids to manipulate the gene during the transfer and to rescue it for analysis afterwards. This is valuable for several reasons. The first and simplest is that it generates a cell which has a single new gene product. As the functions of most gene products are still unknown, this should greatly help us to find out what these functions are. For example, the function of the great majority of membrane glycoproteins such as Thy 1, Lyt 1, and T5/T8 remains to be understood. Most membrane glycoproteins have so far been defined only as antigens, sometimes and to an increasing extent through the use of monoclonal antibodies. It turns out to be very difficult to find out what these glycoproteins do, even after quite a lot has been found out about their structure. The Thy 1 molecule is a case in point. It was discovered 18 years ago, it has been used as a marker in lymphocyte differentiation for 13 years, and its primary structure has now been unravelled , yet we still know next to nothing about its function. Up to a point the classical approaches of genetics can be applied to these problems: analysis by means of loss and temperature-sensitive mutations. Nowadays these may be supplemented by segregation analysis, in which a cell positive for a given glycoprotein and a given function is fused with a negative cell and the daughter cells analysed for co-expression of the glycoprotein and the function . But progress using classical genetics has been slow, and the contribution to be exprected from transfection is accordingly great. With some justice one could argue that transfection is not a new departure in principle since it merely uses positive variants where classical genetics uses negative variants. However there are many reasons for expecting these positive variants to be far more valuable.
KeywordsMembrane Glycoprotein Congenic Strain Associative Recognition Classical Genetic Congenic Line
Unable to display preview. Download preview PDF.
- 4.Bromberg J, Brenan M, Clark E, Lake P, Mitchison NA, Nakashima I, Sainis K (1979) Associative recognition in the response to alloantigens (and xenogenisation to alloantigens). Gan 23:185–192Google Scholar
- 12.Mellor AL, Golden L, Weiss E, Bullman H, Hurst J, Simpson E, James R, Townsend ARM, Taylor PM, Schmidt W, Ferluga J, Leben L, Santamaria M, Atfield G, Festenstein H, Flavell RA (1982) Expression of the murine H-2Kb histocompatibility antigen in cells transformed with cloned H-2 genes. Nature 298:529–533PubMedCrossRefGoogle Scholar
- 13.Mitchison NA (1979) Regulation of the response to cell surface antigens. In: Ferrone S, Gorini S, Herberman RB, Reisfeld RA (eds) Current trends in tumor immunology. Garland-STPM, New York, pp 111–118Google Scholar
- 16.Mitchison NA, Kinlen L (1980) Present concepts in immune surveillance. In: Fougereau M, Dausset J (eds) Immunology 1980. Academic, London, pp 641–650Google Scholar
- 17.Mitchison NA, Lake P (1978) Latent help. In: Sercarz EE, Herzenberg LA, Fox CF (eds) Immune system: Genetics and regulation. ICN-UCLA Symposium Immune System, Park City, Utah, 1977. Academic, New York, pp 555–558Google Scholar
- 18.Simonsen M (1981) The major histocompatibility complex in a bird’s-eye view. In: Zaleski MB, Abeyounis CJ, Kano K (eds) Immunobiology of the major histocompatibility complex. 7th International Convocation of Immunology, 1980. Karger, Basel, pp 192–201Google Scholar
- 20.Stern PL (1973) Theta alloantigen on mouse and rat fibroblasts. Nature 246:76–78Google Scholar
- 24.Yeh Ming, Czitrom AA, Mitchison NA (1982) Allospecific T-cell lines with functional activities. Immunology 46:281–287Google Scholar
- 25.Zaleski MB, Gorzynski TJ (1981) The Ir phenomenon and the MHC restriction: differences and similarities. In: Zaleski MB, Abeyounis CJ, Kano K (eds) Immunobiology of the major histocompatibility complex. 7th International Convocation of Immunology. Karger, Basel, pp 98–107Google Scholar