In vitro detection and characterization of drug hypersensitivity using flow cytometry.
BACKGROUND
The lymphocyte transformation test (LTT) is the only in vitro test for detecting drug sensitization at the cellular level irrespective of the reaction's phenotype. However, the LTT includes working with radioactive substances and is considered impracticable for routine laboratory investigation.


OBJECTIVE
The aim of this study was to assess drug-specific cytokine production by means of flow cytometry as an alternative nonradioactive approach which may be more appropriate for routine testing and may provide in addition more information about the pathophysiology of the reaction than proliferation-based assays, like the LTT.


METHODS
Peripheral blood mononuclear cells of 19 patients were incubated with culprit drugs (n = 28) or irrelevant antigens (n = 10). Ten healthy persons served as controls for all different drugs (n = 15). Intracellular interleukin (IL)-5, interferon (IFN)-gamma and IL-10 production was investigated using flow cytometry. Accuracy of the flow cytometry test system was confirmed using different statistical tests, i.e. receiver operating characteristic curve and Mann-Whitney rank test. In addition, drug-specific secretion of IL-5, IL-2 and IFN-gamma were analysed using enzyme-linked immunosorbent assay (ELISA).


RESULTS
Drug-specific cytokine production could be demonstrated in 75% of the patients using flow cytometry and in 79% using ELISA respectively. Combining ELISA and flow cytometry increased the sensitivity to 100%. Analysis of involved T-cell subsets [e.g. CD4(+) or CD8(+); T helper (TH) 1 or TH 2] allowed characterization of the in vitro lymphocyte reactivity pattern.


CONCLUSIONS
Analysis of drug-specific cytokine production by means of flow cytometry proved a useful and reliable approach for the in vitro detection and characterization of drug hypersensitivities.
Federal Institute for Drugs and Medical Devices, Bonn, Germany.
M
M
Martin
G
G
Wurpts
H
H
Ott
J M
JM
Baron
S
S
Erdmann
H F
HF
Merk
B
B
Sachs
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002469:Cell Separation; D016207:Cytokines / Q000096:biosynthesis; D004342:Drug Hypersensitivity / Q000175:diagnosis*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D066298:In Vitro Techniques; D008875:Middle Aged; D012372:ROC Curve; D012680:Sensitivity and Specificity
D016207:Cytokines