Liposome immune assay (LIA). Use of membrane antigens inserted into labeled lipid vesicles as targets in immune assays.
A new method is described for detection of membrane antigens and antibodies against such structures. By inserting partially purified rat transplantation antigen (RT-1) into iodine or fluorescein-labeled lipid vesicles, a precipitation of the liposome is demonstrated by the use of a specific alloantiserum and a heterologous anti-rat IgG serum. Precipitation of liposomes carrying WF transplantation antigens could be detected at a final dilution of the alloantiserum of 1:3000, which is comparable to that obtained in a 51Cr-release assay. Furthermore, when unpurified membrane proteins from WF splenocytes were incorporated into labeled liposomes, an amount of RT-1 corresponding to 8000 cells could be detected.
D000818:Animals; D000954:Antigens, Surface / Q000032:analysis*; D005452:Fluoresceins; D006649:Histocompatibility Antigens / Q000032:analysis; D007158:Immunologic Techniques; D007457:Iodine Radioisotopes; D008081:Liposomes / Q000276:immunology*; D008563:Membrane Lipids; D008565:Membrane Proteins / Q000276:immunology*; D051381:Rats
D000954:Antigens, Surface; D005452:Fluoresceins; D006649:Histocompatibility Antigens; D007457:Iodine Radioisotopes; D008081:Liposomes; D008563:Membrane Lipids; D008565:Membrane Proteins