Lactate promotes dengue virus type 2 infection by modulating macrophage function
10.3760/cma.j.cn112309-20240102-00001
- VernacularTitle:乳酸调控巨噬细胞功能促进登革病毒2型感染
- Author:
Huan HU
1
;
Yanchun QIN
;
Zhenzhi HUANG
;
Lu ZHOU
;
Jiahong WU
;
Zhengling SHANG
Author Information
1. 贵州医科大学基础医学院免疫学教研室，安顺 550025
- Keywords:
Lactate;
Macrophage;
Dengue virus;
Viral replication;
M2 macrophage polarization;
Interferon signaling pathway
- From:
Chinese Journal of Microbiology and Immunology
2024;44(5):396-405
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the impact of exogenous lactate on the replication of dengue virus type 2 (DENV-2) in Raw264.7 cells, mouse bone marrow-derived macrophages (BMDMs) and THP-1 cells and explore its association with cell activation.Methods:BMDMs from BALB/c mouse bone marrow were prepared and evaluated by flow cytometry to detect the proportion of F4/80 + CD11b + cells. Glucose transporter type 1 (GLUT1), hexokinase 2 (HK2), and monocarboxylate transporters 4 (MCT4) expression at mRNA level in BMDMs at different time points after DENV-2 infection were measured by qRT-PCR. The content of lactate in the culture supernatants was quantified via colorimetric assay. CCK-8 assay was used to evaluate the impacts of different concentrations of lactate on the viability of Raw264.7 cells, BMDMs, and THP-1 cells. qRT-PCR was used to detect the expression of DENV-2 E gene, TGF-β, CD86, retinoic acid-inducible gene Ⅰ (RIG-Ⅰ), IFN-β, interferon-stimulated gene 15 (ISG15), and ISG56 at mRNA level in cells infected with DENV-2 at different MOIs in the presence of different concentrations of lactate. Meanwhile, flow cytometry was used to analyze the expression of CD86 and CD206. Results:The percentage of BMDMs was (87.53±1.66)%. GLUT1 expression at mRNA level exhibited a decrease in BMDMs at 24 h after DENV-2 (MOI=3) infection following a transient increase at 12 h ( P<0.05), while HK2 expression at mRNA level was higher that than in blank control and inactivated DENV-2 infection groups at 12, 24, and 36 h ( P<0.01). Besides, there was an increase in both MCT4 mRNA level and the content of lactate in culture supernatants at 24 h after DENV-2 (MOI=1.5) infection ( P<0.05). The viability of the three types of cells remained above 80% when the concentration of lactate was 31.25 mmol/L. Lactate at the concentration of 35 mmol/L increased the expression of the DENV E gene at mRNA level in DENV-2-infected BMDMs at MOI=1 or MOI=2 ( P<0.05). Besides, it promoted the expression of DENV E gene at mRNA level in Raw264.7 and THP-1 cells ( P<0.001) as well as the expression of CD163, TGF-β, RIG-Ⅰ, IFN-β, ISG15 and ISG56 at mRNA level in BMDMs at MOI=1.5, but inhibited the expression of CD86 at mRNA level in BMDMs ( P<0.05). It also up-regulated CD206 protein expression ( P<0.01) and down-regulated CD86 protein expression ( P>0.05) in BMDMs. Conclusions:Exogenous lactate enhances DENV-2 replication in both human- and murine-derived macrophages and that might correlate with M2 macrophage polarization.
