Analysis of differential gene expression of PBMC for the in vitro detection of drug sensitization

Abstract

Background: The detection of drug-specific activation of T cells in the lymphocyte transformation test (LTT) is mainly based on cell proliferation or cytokine secretion. However, the LTT presents with a varying sensitivity and specificity. The aim of our study was to analyse the genome wide gene expression of PBMC to identify drug allergy-specific gene regulation patterns. Additionally, gene expression differences related to the allergy-inducing drug or the type of allergy (immediate/delayed) were investigated.

Methods: Blood samples from 40 patients with allergy to different drugs and from 40 non-drug-allergic controls were recruited. PBMC were isolated and stimulated with the culprit drug (“LTT-platform”). Transcriptome analyses of PBMC were conducted after 3.5 days. The concentration of IFN-γ and IL-5 in the culture supernatants was measured by ELISA after 6 days.

Results: The transcriptome analyses revealed an allergy type and drug-specific gene regulation in PBMC from patients. Importantly, in the corresponding control groups these genes were barely or even opposingly regulated. It was also shown that in particular cefuroxime exerted a strong effect on the gene regulation in PBMC. Quantitative RT-PCR of selected genes identified by the transcriptome analyses revealed that CCL17, CISH and CD25 were specifically upregulated in patients. Notably, a strong upregulation of CCL17, CISH or CD25 did not necessarily correlate with the ELISA outcome of the patients and controls.

Conclusions: Our results could be helpful for the identification of one or a panel of regulated genes considering patient specific parameters like the type of the allergy-inducing drug.