A preliminary study on the biomimetic drug delivery system targeting atherosclerotic lesions / 药学学报

Based on the natural affinity between macrophages and atherosclerotic lesions, we made a novel macrophage membrane-coated polylactic acid-glycolic acid copolymer (PLGA) nanoparticle (MPLNPs), and examined its ability targeting atherosclerotic lesions. PLGA nanoparticle (PLGANPs) were prepared by precipitation and MPLNPs were prepared by membrane extrusion. Their morphology, particle size and retainment of functional proteins were characterized. Their targeting capabilities were investigated with cell uptake assay in vitro and fluorescence imaging in vivo. The results showed that MPLNPs were spherical, with obvious core/shell structure, the average particle size was (167 ±6.12) nm, and integrin α4β1 was retained on the surface. Vascular cell adhesion molecule 1 (VCAM-1) receptor was highly expressed in the LPS (lipopolysaccharides)-HUVEC (human umbilical vein endothelial cells) and atherosclerotic lesions in ApoE-/- mouse model, and the nanoparticles could effectively recognize the VCAM-1 receptor and had good targeting properties in vitro and in vivo. The results suggest that the cell membrane biomimetic nano-carrier may provide a new approach for the targeting strategy in the treatment of atherosclerosis and related diseases.

The changes and significance of integrin α4β7 and L-selectin levels in critical children / 中国医师进修杂志

Objective To explore the changes ofintegrin α4β7 and L-selectin levels and the possible relationship between the changes and intestinal mucosal immune function in critical children with gastrointestinal dysfunction.Methods Forty-eight admitted critical children were divided into non-gastrointestinal dysfunction group (29 cases) and gastrointestinal dysfunction group (19 cases),and also compared with 25 healthy people (control group).The expression of integrin α 4β 7 and L-selectin was measured by flow cytometry.Results The expression of integrin α 4β 7 in gastrointestinal dysfunction group [(11.11 ± 1.15)％] was lower than that in non-gastrointestinal dysfunction group [(15.36 ± 1.26)％]and control group [(19.62 ±0.89)％] (P ＜0.05),but there was no significant difference between nongastrointestinal dysfunction group and control group(P ＞ 0.05).The expression of L-selectin in gastrointestinal dysfunction group [(60.68 ±3.72)％] was lower than that in non-gastrointestinal dysfunction group [(69.43 ± 1.52)％] and control group [(88.65 ± 2.41)％] (P ＜ 0.05),and there was significant difference between non-gastrointestinal dysfunction group and control group (P ＜ 0.05).Conclusion The expression of integrin α 4β 7 and L-selectin is decreased at the early stage of gastrointestinal dysfunction in critical childern,and integrin α 4 β 7 is decreased sharply.