title: Detection of IgM autoantibodies in eluates from red blood cells.
abstract: Forty-two patients with autoimmune haemolysis, whose red cells were sensitized with IgM, were studied in order to determine suitable techniques for investigating the form of erythrocyte-bound IgM, particular emphasis being placed on identifying forms of low molecular weight. Four elution techniques were assessed for their efficiency in removing cell-bound IgM; these were the heat elution, acid stromal, organic solvent and freeze-thaw methods. Eluted IgM was detected by polyacrylamide gel electrophoresis followed by immunoblotting; the heat elution method proved to be the best. Although oligomeric forms of IgM were found in 64% of patients' sera tested concurrently, only pentameric IgM was eluted; from this it was concluded that low molecular weight IgM was not causing haemolysis in any of the cases studied but that the methods would readily detect its presence.
authors.affiliation: Regional Blood Transfusion Centre, Sheffield, UK.
authors.forename: J P
authors.initials: JP
authors.lastname: Ellis
authors.forename: R J
authors.initials: RJ
authors.lastname: Sokol
mesh_terms: D001323:Autoantibodies / Q000032:analysis*; D002725:Chloroform; D004591:Electrophoresis, Polyacrylamide Gel; D004912:Erythrocytes / Q000276:immunology*; D005615:Freezing; D006461:Hemolysis / Q000276:immunology; D006358:Hot Temperature; D006801:Humans; D006851:Hydrochloric Acid; D015151:Immunoblotting; D007075:Immunoglobulin M / Q000032:analysis*; D008970:Molecular Weight; D014241:Trichloroethylene
chemical_list: D001323:Autoantibodies; D007075:Immunoglobulin M; D014241:Trichloroethylene; D002725:Chloroform; D006851:Hydrochloric Acid