[The role of 12-alkylated chitosans/plasmid-encoding antisense endothelin converting enzyme complex nanoparticles in immunomodulation of allergic airway inflammation].
OBJECTIVE
To explore a novel nonspecific immunomodulation for the treatment of allergic airway inflammation by RNA interference for endothelin converting enzyme (ECE) using 12-alkylated chitosans/plasmid-encoding antisense ECE complex nanoparticles.


METHODS
Forty BALB/c mice were randomly divided into Group N (normal control), Group NM (OVA + 12-ACSs/antisense-ECE plasmid), Group As (OVA) and Group DNA (OVA + antisense-ECE plasmid), and sensitized by intraperitoneal injection of OVA at day 1 and day 14, followed by challenge with aerosol of 1% OVA at day 24, 25 and 26, but with saline as a control (N). Supernatants from cultured splenocytes and lung homogenates were subjected to detection of the levels of interleukin-4, 5, 10, 13 (IL-4, 5, 10, 13), interferon-gamma (IFN-gamma) and endothelin-1 (ET-1) by using ELISA. Lung tissues were embedded, sliced and HE stained for histopathologic examination. The cultured splenocytes were subjected to flow cytometry detection (IL-4, IL-10 and IFN-gamma).


RESULTS
Mice in group NM showed a lower level of cell count than that in either group AS or group DNA. Compared with N group, the lung tissues taken from the mice in As and DNA groups displayed allergic inflammation with eosinophil infiltration, while the pulmonary inflammation was decreased significantly in group NM. The levels of ET-1, IL-4, IL-13 and IL-5 were down regulated in group NM compared to As and DNA groups (P < 0.05 or P < 0.01). After stimulation by OVA, the splenocytes from the mice in NM group produced a higher level of IL-10 than that from As and DNA groups (P < 0.05 or P < 0.01). The number of Th2 lymphocytes (CD(4)(+) T cells with IL-4 expression) was significantly elevated in the mice of As, DNA and NM groups respectively, while the number of Th2 lymphocytes was lower in the mice of group NM than in the mice of group As or group DNA. The number of CD(4)(+)CD(25)(+) cells with IL-10 expression was up-regulated in the mice of As, DNA and NM groups respectively compared to the control. The percentage of T regulating cells was higher in the mice of group NM compared with that in the mice of group As or group DNA. No detectable difference in the level of Th1 cells (CD(4)(+) T cells with IFN-gamma expression) was found among the 4 groups.


CONCLUSIONS
12-ACSs can encapsulate and deliver antisense-ECE expression plasmid into bronchial epithelial cells in vitro and 12-ACSs/antisense ECE plasmid complex nanoparticles have the capability to down regulate the synthesis of ET-1 and thus decrease the allergic airway inflammation in OVA-sensitized mice.
Zhou
Yu-Tian
YT
Institute of Respiratory Disease, Affiliated First Hospital, Guangzhou Medical College, Guangzhou 510120, China. gzyxy2001@yahoo.com.cn
Xu
Jun
J
D000818:Animals; D016282:Aspartic Acid Endopeptidases / Q000235:genetics*; D048271:Chitosan; D019332:Endothelin-1 / Q000096:biosynthesis; D000072396:Endothelin-Converting Enzymes; D005260:Female; D007249:Inflammation; D008666:Metalloendopeptidases / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D053758:Nanoparticles / Q000627:therapeutic use*; D010957:Plasmids; D011014:Pneumonia / Q000628:therapy; D012130:Respiratory Hypersensitivity / Q000628:therapy*
D019332:Endothelin-1; D048271:Chitosan; D016282:Aspartic Acid Endopeptidases; D008666:Metalloendopeptidases; D000072396:Endothelin-Converting Enzymes