Apoptosis- and survival-related gene mRNA profile in peripheral blood leukocytes in children with acute EBV infectious mononucleosis

Abstract

Acute EBV-associated mononucleosis develops mainly in children and in patients with functionally impaired immune system. Consequently, it may result in developing secondary immunodeficiency, neoplasms as well as diverse alterations in cell-mediated immune reaction. Despite extensively examining molecular mechanisms of EBV infection, it is also necessary seek for new molecular and genetic factors underlying pathogenesis of EBV-mediated mononucleosis and EBV-associated malignant cell transformation is necessary, which might be used in clinical practice to monitor clinical score as well as predictive parameters for EBV-associated complications such as immunocompromised conditions and neoplasms. Here, we proposed to use our splicing sensitive DNA microarrays to perform a comprehensive semi-quantitative mRNA expression analysis for major apoptosis- and survival-related signaling components in peripheral blood leukocytes collected from children with acute EBV infectious mononucleosis as well as during recovery period. Using such DNA microchips allowed to assess both total (denoted by Σ) and separate transcript expression resulting from alternative splicing. It was shown that the balance of mRNA levels in acute phase of EBV-infectious mononucleosis was shifted towards upregulated expression of anti-apoptotic factors and components of of NF-κB-linked pro-survival signaling able to profoundly augment apoptosis resistance. Moreover, some EBV-associated changes (BIM/BCL2L11-Σ, PUMA/ BBC3-NM_001127241, BID-Σ, CASP3-Σ, NFKB1-Σ, RELA-Σ) were in agreement with the data published before. In addition, we also found previously unknown changes in level of EBV-associated coding and noncoding transcripts (DCR1/ TNFRSF10C-NM_003841, DR5/TNFRSF10B-NR_027140, CASP6 beta/CASP6-NM_032992, CASP7-NM_033338). Analyzing their properties allowed to suggest that they play an important role in the pathogenesis of EBV-associated mononucleosis. However, at asymptomatic recovery stage, level of some mRNA expression was kept altered compared to healthy volunteers (DCR2/TNFRSF10D-NM_003840, CASP8-Σ, CASP3-Σ, BIM/BCL2L11-Σ, BCL2-NM_000633, MCL1-Σ, BCL-W/BCL2L2-Σ, BCL-XL/BCL2L1-NM_138578, BIRC2-NM_001166, XIAP-NM_001167, TRAF2-NM_021138, MAP3K14-Σ, NFKB1-Σ), which may point at postponed EBV-associated molecular consequences. On one hand, such changes may be due to long-lasting anti-EBV immune response, whereas, on the other hand, they might be influenced by EBV-associated factors facilitating virus persistence. Overall, we identified the molecular features predisposing to chronic course of EBV-infection. The data obtained further expand our understanding about the molecular pathogenetic mechanisms for EBV infectious mononucleosis.

Keywords

• ebv-infectious mononucleosis
• leukocytes
• mrna expression levels
• apoptotic and survival pathways