Previous Article | Next Article ![]()
Clinical and Diagnostic Laboratory Immunology, 03 1997, 202-207, Vol 4, No. 2
P von Zons, P Crowley-Nowick, D Friberg, M Bell, U Koldovsky and TL Whiteside
Natural killer (NK) and lymphokine-activated killer (LAK) cell activities
were measured in peripheral blood obtained from healthy women to compare a
standard 51Cr release assay with a nonradioactive europium (Eu3+) release
assay based on time-resolved fluorescence. The two types of cytotoxicity
assays were first compared in paired determinations performed on 28 samples
of peripheral blood mononuclear cells obtained from healthy women who had
normal pap smears or no biopsy evidence of cervical squamous
intraepithelial lesions (SIL). Target cells (NK-sensitive K562 and
NK-resistant Raji cell lines) were labeled with Eu3+ only, 51Cr only, or
both labels and compared in cytotoxicity assays using fresh or interleukin
2 (IL-2)-activated effector cells. Spontaneous release in the Eu3+ release
assay was comparable to that observed in the 51Cr release assay, but
maximum Eu3+ release always exceeded that of 51Cr. In 4-h assays, specific
release of Eu3+ from target cells was more rapid than that of 51Cr,
consistently resulting in 30 to 40% higher levels of activity. However, a
significant linear correlation (P < 0.001) was observed between
cytotoxicity levels based on measurements of Eu3+ and 51Cr release in 4- h
assays. The Eu3+ release assay was then used to measure NK and LAK
activities in the peripheral blood of women with cervical SIL or cervical
squamous cell carcinoma (SCC). Mean NK activity of women with advanced SIL
(121 lytic units [LU]) or SCC (93 LU) was found to be similar to that of
controls (101 LU) or patients with normal cervical biopsies (90 LU), as was
the ability to generate IL-2-stimulated NK activity. However, LAK activity
during 18 h of incubation in the presence of IL-2 was reduced in patients
with cervical SCC (P < 0.05) compared with that in normal controls.
Results of 51Cr assays performed in parallel with patient samples gave
comparable results. Advantages of EU3+ release assays for routine
evaluation of cytotoxicity are discussed.
Copyright © 1997 by the American Society for Microbiology. All rights reserved.
Comparison of europium and chromium release assays: cytotoxicity in healthy individuals and patients with cervical carcinoma
Department of Obstetrics/Gynecology, University of Dusseldorf, Germany.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»