Objective To identify the expression of sphingosine-1-phosphate receptor (S1PR) subtypes, C-myc and His tag proteins of human umbilical vein endothelial fusion cell line, EA.hy926 and human umbilical vein endothelial cells (HUVEC), CRL-1730 for studying the function of apolipoprotein M (ApoM)-S1P axis. Methods Two kinds of cells (EA. hy926 and CRL-1730) were cultured to reach the density of 60%-70% in vitro. Immunofluorescence technique was em?ployed to investigate the expressions of coagulation factorⅧ(FⅧ), ApoM, S1PR1-S1PR5, C-myc and His tag proteins. Re?sults (1) Two kinds of cells both expressed FⅧand ApoM. FⅧpresented scattered particle distribution in CRL-1730, while uniform distribution in EA.hy926. However, ApoM was strongly expressed and widely distributed in cytoplasm of two kinds of cells. (2) S1PR1-3 can be detected on their membrane other than S1PR4 and S1PR5. S1PR1 was highly expressed but S1PR2 and S1PR3 were in a low level expression. (3) Two kinds of cells both expressed C-myc and His tag proteins in cytoplasm. Conclusion Two kinds of cells have the properties of endothelial cells and can express FⅧ, ApoM, C-myc and His tag proteins. It is not suitable for choosing C-myc and/or His tag–conjugated recombinant ApoM to study the fuction of ApoM-S1P axis with these two kinds of cells.

Background Studies on the association between greenness exposure and allergic rhinitis (AR) in children are mostly conducted in developed countries, and the conclusion is not consistent. Objective Using street view data to explore the association between greenness exposure and allergic rhinitis (AR) prevalence in Chinese children. Methods A cross-sectional study was conducted among 40868 children aged 2-17 years in three cities of Northeast China from 2012 to 2013, which consisted of 20886 (51.1%) boys and 19982 (48.9%) girls. The information of AR prevalence was obtained through questionnaire. Based on downloaded street view images from Tencent Maps, a green view index (GVI) of green vegetation (trees and grass) within 800 m and 1000 m buffer of the participants' schools was calculated by using artificial intelligence, and it was used as a surrogate of the greenness exposure. A mixed-effect logistic regression model was used to estimate the odds ratio (OR) of AR prevalence in children for per increase of inter-quartile range (IQR) of GVI. In addition, according to ambient PM_2.5 concentration, the participants were divided into a low PM_2.5 exposure group (≤56.23 μg·m⁻³) and a high exposure group (>56.23 μg·m⁻³) to investigate whether PM_2.5 was a modifier on the association between GVI and AR. Results The average age of the subjects was (10.40±3.68) years and 3 963 (9.7%) subjects reported diagnosed AR. Within 800 m buffer, an IQR increase in GVI for trees (IQR=0.031, OR=0.85, 95%CI: 0.81-0.90) and overall greenness (IQR=0.029, OR=0.86, 95%CI: 0.81-0.90) was associated with lower adjusted odds ratio of AR. The interaction between PM_2.5 and GVI was statistically significant (P< 0.1), that is, the negative associations of trees and overall greenness with AR were observed only at low PM_2.5 exposure levels. The sensitivity analysis results of GVI within 1000 m buffer was consistent with that within 800 m buffer. Conclusion Exposure to green vegetation, especially trees, may be associated with decreased risks of AR in children, and such associations may be more obvious in areas with a low PM_2.5 concentration.