title: Measurement of serum interleukin-2 activity.
abstract: The accurate measurement of serum interleukin-2 activity is crucial for assessing the efficacy and toxicity of systemic immunotherapy with recombinant interleukin-2. Incubation of serum at 56 degrees C for 30 minutes facilitates the bioassay for interleukin-2 activity by destroying the interleukin-2 inhibitory activity native to human serum. As this report will demonstrate, however, 30% to 50% of interleukin-2 activity in serum taken from patients or normal volunteers was destroyed by heating at 56 degrees C. No loss of recombinant interleukin-2 activity occurred during heating in serum-free media. The percentage of interleukin-2 activity lost at 56 degrees C varied from patient to patient and also varied with the time of exposure. Native serum interleukin-2 inhibitory activity can be removed, and interleukin-2 activity can be assessed accurately in serial dilutions of the serum beyond 1:64.
authors.affiliation: Department of Surgery (Urology), Metropolitan General Hospital, Case Western Reserve University, Cleveland, Ohio 44109.
authors.forename: J D
authors.initials: JD
authors.lastname: Fleischmann
authors.forename: D B
authors.initials: DB
authors.lastname: Wentworth
authors.forename: K M
authors.initials: KM
authors.lastname: Thomas
authors.forename: A L
authors.initials: AL
authors.lastname: Imbembo
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006358:Hot Temperature; D006801:Humans; D007201:Indicator Dilution Techniques; D007376:Interleukin-2 / Q000097:blood*; D011994:Recombinant Proteins / Q000032:analysis; D013696:Temperature; D013997:Time Factors
chemical_list: D007376:Interleukin-2; D011994:Recombinant Proteins