ABSTRACT
Objective:To explore the value of monocyte subsets and CD64 expression in the diagnosis and prognosis of sepsis.Methods:A prospective case-control study was designed. 30 septic patients and 30 non-septic patients who were admitted to the intensive care unit (ICU) of the PLA Army Characteristic Medical Center from March 2021 to March 2022 were enrolled. After 1, 3, and 5 days of ICU admission, peripheral blood samples were taken from patients. Flow cytometry was used to detect the proportion of monocyte subsets and the expression level of CD64 on the surface, and the difference of expression between patients in two group was analyzed. The risk variables for sepsis were analyzed using single-factor and multi-factor Logistic regression. The diagnostic efficacy of each risk factor for sepsis was determined using the receiver operator characteristic curve (ROC curve).Results:One day after ICU admission, the proportions of monocytes and classic monocytes in white blood cells (WBC) of septic patients were significantly lower than those of non-septic patients [proportion of monocytes to WBC: (4.13±2.03)% vs. (6.53±3.90)%, proportion of classic monocytes to WBC: 1.97 (1.43, 2.83)% vs. 3.37 (1.71, 5.98)%, both P < 0.05]. The proportion of non-classical monocytes in monocytes was significantly higher in septic patients than that in non-septic patients [(11.42±9.19)% vs. (6.57±4.23)%, P < 0.05]. The levels of CD64 expression in monocytes, classic monocytes, intermediate monocytes and non-classic monocytes were significantly higher in sepsis patients than those in non-septic patients [mean fluorescence intensity (MFI): 13.10±6.01 vs. 9.84±2.83 for monocytes, 13.58±5.98 vs. 10.03±2.84 for classic monocytes, 13.48±6.35 vs. 10.22±2.99 for intermediate monocytes, 8.21±5.52 vs. 5.79±2.67 for non-classic monocytes, all P < 0.05]. Multivariate Logistic regression research showed that CD64 in typical monocytes [odds ratio ( OR) = 1.299, 95% confidence interval (95% CI) was 1.027-1.471, P = 0.025] and the proportion of non-typical monocytes in monocytes ( OR = 1.348, 95% CI was 1.034-1.758, P = 0.027) were the independent risk factors for sepsis. ROC curve showed that the area under the ROC curve (AUC) of CD64 expression of classical monocytes, the fraction of non-classical monocytes in monocytes, and procalcitonin (PCT) in the diagnosis of sepsis was 0.871. A correlation analysis revealed a negative relationship between the acute physiology and chronic health status evaluation Ⅱ (APACHE Ⅱ) on the first, third, and fifth days following ICU admission and the expression level of CD64 in patients' classic monocytes ( r values were -0.264, -0.428 and -0.368, respectively, all P < 0.05). Conclusions:Combining the proportion of non-classical monocytes in monocytes, the level of plasma PCT, and the CD64 expression of classic monocytes in peripheral blood has good efficacy in identifying sepsis and assessing its severity.
ABSTRACT
Objective To explore effects of apoAI on MCP?1 levels in the plasma and the Ly6Chi monocyte proportion in the blood and spleen of atherosclerotic mice,as well as on CCR2 expression in vitro. Methods Sixteen male apoE?/?mice were fed with high cholesterol diet for 12 weeks. Mice were randomly divided into control and apoAI groups and were administered with PBS or apoAI(40 mg/kg),respectively,via tail vein on the 1st and 3rd day before sacrifice. Mice in both groups were administered LPS(25μg/mouse)via intraperitoneal injection 12 h before sacrifice. Plas?ma levels of MCP?1 were determined using ELISA,and the Ly6Chi monocyte proportion was analyzed using flow cytometry. In addition,human monocytic THP?1 cells were randomly divided into control and apoAI(10 mg/L)?treated groups,pretreated with corresponding intervention,and incubated with LPS(10μg/L). CCR2 expression levels were measured by Western blotting. Results Compared with the control treatment, apoAI treatment remarkably reduced MCP?1 levels in plasma and Ly6Chi monocyte proportion in the blood and spleen(P<0.01). Furthermore, apoAI treatment inhibited CCR2 expression in monocytes in vitro(P<0.05). Conclusion apoAI can reduce MCP?1 levels in plasma and the Ly6Chi monocyte proportion in the blood and spleen and can inhibit CCR2 expression in monocytes in vitro.