Dectin-1 and TIM3 Expression in Deep Vein Thrombosis of Lower Limbs (DVTLL)

Abstract

The pathophysiological mechanisms of venous thromboembolism are venous stasis, endothelial damage, and hypercoagulability, while less attention has been given to the role of both innate and native immunity. In this paper, we investigate the involvement of the activated immune system detected through some indicators such as TIM3 and Dectin-1 expressed by T lymphocytes. TIM3 and Dectin-1, two surface molecules that regulate the fine-tuning of innate and adaptive immune responses, were evaluated in patients affected by deep vein thrombosis of lower limbs (DVTLL). CD3⁺, CD4⁺ and CD8⁺ T lymphocytes obtained from patients affected by DVTLL were analysed using fluorescence-conjugated antibodies for TIM3 and Dectin-1 by an imaging flow cytometer. DVTLL patients showed a higher number of CD4⁺ and CD8⁺ T lymphocytes. TIM3 expression in T lymphocytes was very low in both DVTLL patients and controls. On the contrary, an increase in Dectin-1⁺ cells among CD4⁺ and CD8⁺ T lymphocytes from DVTLL patients was observed. Dectin-1 is known to play a role in inflammation and immunity and our result suggests its potential involvement in thrombotic venous disease.

Keywords: Dectin-1; T lymphocyte; TIM3; deep vein thrombosis; immunity; inflammation.

Figure 1

Flow cytofluorimetric analysis workflow. The image shows the sequential procedure and the microphotographs of stained cells (A–H) using five different monoclonal fluorescent dye-coupled anti-human antibodies and analysed by flow cytometry (Amnis FlowSight). For each patient, four aliquots of lymphocyte suspensions (100 µL) were stained with antibodies using four different combinations (10 µL of each antibody). Representative stained cells (event) for each of the four combinations are shown: CD-3⁺ CD-4⁺ TIM-3⁺ (A); CD-3⁺ CD-4⁺ Dectin-1⁺ (B); CD-3⁺ CD-8⁺ TIM-3⁺ (C); CD-3⁺ CD-8⁺ Dectin-1⁺ (D). Tim3⁻ and Dectin-1⁻ cells are also shown: CD3⁺ CD-4⁺ TIM-3⁻ (E); CD-3⁺ CD-4⁺ Dectin-1⁻ (F); CD-3⁺ CD-8⁺ Tim3⁻ (G); CD-3⁺ CD-8⁺ Dectin-1⁻ (H).

Figure 2

Expression of TIM3 and Dectin-1 in CD3⁺, CD4⁺ and CD8⁺ T lymphocytes belonging to DVTLL patients and healthy controls was analysed by flow cytofluorimetric analysis. The number of CD3⁺/CD4⁺ and CD3⁺/CD8⁺ cells was higher in DVTLL patients (A,D). No differences were observed for CD4⁺/TIM3⁺ and CD8⁺/TIM3⁺ cells between DVTLL patients and controls (B,E). The number of CD4⁺ and CD8⁺ cells expressing Dectin-1 (C,F) was significantly higher in DVTLL patients. Statistical analysis was performed by a Mann–Whitney test. * p < 0.05; **** p < 0.0001.