title: Evaluation of X-radiation and UV-B radiation for elimination of 3H-thymidine incorporation into responder cells in the IL-2 producing helper T lymphocyte precursor assay.
abstract: The helper T lymphocyte precursor (HTLp) assay is of value for predicting graft-vs.-host disease after allogeneic bone marrow transplantation. The assay is based on limiting dilution analysis and requires detection of the amount of interleukin 2 (IL-2) produced by one activated T cell. IL-2 is detected by 3H-thymidine (3H-TdR) incorporation into the IL-2 dependent cell line, CTLL-2. Detection of IL-2 in the whole culture volume of the wells in the microtiter plates increases sensitivity, but requires elimination of 3H-TdR incorporation into the responder cells in the HTLp assay. We have compared the ability of X-radiation and ultraviolet B (UV-B) radiation to eliminate 3H-TdR incorporation. X-irradiation of the cells reduced 3H-TdR incorporation by 90% with doses up to 400 Gy, but the incorporation was still 10 times higher than in wells with stimulator cells only. UV-B irradiation (with Philips TL 12 tubes) of the cells with > or = 2 J/cm2 decreased 3H-TdR incorporation to the level of wells with stimulator cells only. Neither X-irradiation nor UV-B irradiation of the cultures affected IL-2 produced in the assay or human recombinant IL-2 measured by 3H-TdR incorporation into the IL-2 dependent cell line, CTLL-2. HTLp frequencies determined after 25 Gy X-irradiation were higher (mean 1.5, range 1.02-2.2 times higher) than HTLp frequencies determined after UV-B irradiation with 2 J/cm2.
authors.affiliation: Department of Haematology, Copenhagen University Hospital, Denmark.
authors.forename: C A
authors.initials: CA
authors.lastname: Russell
authors.forename: H C
authors.initials: HC
authors.lastname: Wulf
authors.forename: P B
authors.initials: PB
authors.lastname: Sørensen
authors.forename: L L
authors.initials: LL
authors.lastname: Vindeløv
mesh_terms: D001681:Biological Assay; D016026:Bone Marrow Transplantation / Q000009:adverse effects; D002460:Cell Line; D002478:Cells, Cultured; D004261:DNA Replication / Q000528:radiation effects*; D004305:Dose-Response Relationship, Drug; D006086:Graft vs Host Disease / Q000276:immunology / Q000517:prevention & control; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis*; D008297:Male; D011994:Recombinant Proteins / Q000494:pharmacology; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D013936:Thymidine / Q000378:metabolism*; D014316:Tritium / Q000032:analysis; D014466:Ultraviolet Rays; D014965:X-Rays
chemical_list: D007376:Interleukin-2; D011994:Recombinant Proteins; D014316:Tritium; D013936:Thymidine