T-LYMPHOCYTES EXPRESSION OF TOLL-LIKE RECEPTORS 2 AND 4 IN ACUTE MYELOID LEUKEMIA PATIENTS WITH INVASIVE FUNGAL INFECTIONS Toll-like receptors 2 and 4 in Acute Myeloid Leukemia Patients with Invasive Fungal Infections

Abstract

Background: Invasive fungal infections (IFIs) are important cause of mortality in acute myeloid leukemia (AML) patients on treatment with intensive induction chemotherapy. Toll-like receptors, mainly Toll-like receptors 2 and 4 (TLR2 and TLR4), play a considerable role in the host defense against microorganisms.  The expression of TLRs and their association with the occurrence of IFIs in patients with AML remains unclear. The aim of this study was to investigate the associations between the T-lymphocyte expression of TLR2 and TLR4 and the occurrence of IFIs in AML patients treated with intensive induction chemotherapy. Materials and Methods: One hundred twenty two newly diagnosed AML patients were evaluated. The laboratory diagnostic techniques for IFIs include culture, microscopic examination, histopathology, galactomannan assay and PCR. The expressions of TLR2 and TLR4 were analyzed by flow cytometry. The Control group included 20 age and sex-matched individuals. Results: There was a significant increase in the expression of TLR4 in AML patients with IFI compared to healthy controls (p = 0.001). TLR2 and TLR4 expressions increased significantly in AML patients with mixed fungal and bacterial infection compared to healthy controls (p= 0.002 and p=0.001, respectively). Conclusion: TLRs expressions could be important biological markers for the occurrence of IFI in AML patients after intensive induction chemotherapy.

Keywords: Invasive Fungal Infection, TLR2, TLR4, Acute Myeloid Leukemia