In vitro drug causality assessment in Stevens-Johnson syndrome - alternatives for lymphocyte transformation test

Clin Exp Allergy. 2013 Sep;43(9):1027-37. doi: 10.1111/cea.12145.


Background: Patients with Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) are often exposed simultaneously to a few potentially culprit drugs. However, both the standard lymphocyte transformation tests (LTT) with proliferation as the assay end-point as well as skin tests, if done, are often negative.

Objective: As provocation tests are considered too dangerous, there is an urgent need to identify the relevant drug in SJS/TEN and to improve sensitivity of tests able to identify the causative drug.

Methods: Fifteen patients with SJS/TEN with the ALDEN score ≥ 6 and 18 drug-exposed controls were included. Peripheral blood mononuclear cells (PBMC) were isolated and cultured under defined conditions with drugs. LTT was compared to the following end-points: cytokine levels in cell culture supernatant, number of granzyme B secreting cells by ELISpot and intracellular staining for granulysin and IFNγ in CD3(+) CD4(+), CD3(+) CD8(+) and NKp46(+) cells. To further enhance sensitivity, the effect of IL-7/IL-15 pre-incubation of PBMC was evaluated.

Results: Lymphocyte transformation tests was positive in only 4/15 patients (sensitivity 27%, CI: 8-55%). Similarly, with granzyme B-ELISpot culprit drugs were positive in 5/15 patients (sensitivity 33%, CI: 12-62%). The expression of granulysin was significantly induced in NKp46(+) and CD3(+) CD4(+) cells (sensitivity 40%, CI: 16-68% and 53%, CI: 27-79% respectively). Cytokine production could be demonstrated in 38%, CI: 14-68% and 43%, CI: 18-71% of patients for IL-2 and IL-5, respectively, and in 55%, CI: 23-83% for IFNγ. Pre-incubation with IL-7/IL-15 enhanced drug-specific response only in a few patients. Specificities of tested assays were in the range of 95 (CI: 80-99%)-100% (CI: 90-100%).

Conclusions and clinical relevance: Granulysin expression in CD3(+) CD4(+) , Granzyme B-ELISpot and IFNγ production considered together provided a sensitivity of 80% (CI: 52-96%) and specificity of 95% (80-99%). Thus, this study demonstrated that combining different assays may be a feasible approach to identify the causative drug of SJS/TEN reactions; however, confirmation on another group of patients is necessary.

Keywords: Stevens-Johnson syndrome; cytokines; granulysin; granzyme B; lymophocyte transformation test; toxic epidermal necrolysis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antigens, Differentiation, T-Lymphocyte / biosynthesis
  • Cytokines / metabolism
  • Cytokines / pharmacology
  • Drug-Related Side Effects and Adverse Reactions / immunology
  • Female
  • Granzymes / metabolism
  • Humans
  • Interleukin-15 / pharmacology
  • Interleukin-7 / pharmacology
  • Leukocytes, Mononuclear / drug effects
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / metabolism
  • Lymphocyte Activation / drug effects
  • Lymphocyte Activation / immunology*
  • Lymphocytes / drug effects
  • Lymphocytes / immunology*
  • Lymphocytes / metabolism
  • Male
  • Middle Aged
  • ROC Curve
  • Stevens-Johnson Syndrome / diagnosis
  • Stevens-Johnson Syndrome / etiology*
  • Stevens-Johnson Syndrome / immunology
  • Young Adult


  • Antigens, Differentiation, T-Lymphocyte
  • Cytokines
  • GNLY protein, human
  • Interleukin-15
  • Interleukin-7
  • Granzymes