Objective To investigate the changes and significance of intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-α (TNF-α) in intestinal mucosa in rats with obstructive jaundice. MethodsTwenty-four SD rats were randomly divided into sham operation (SO) group and bile duct ligation (BDL) group, and each group were randomly divided into the day 7 and day 14 subgroup. The expression of ICAM-1 was assayed by immunohistochemistry. The level of TNF-α was determined by ELISA. The activity of myeloperoxidase (MPO) and diamine oxidase (DAO) was determined as well.ResultsOn the day 7 and 14, in the bile duct ligation group, the ICAM-1 protein was mainly expressed in the intestinal epithelia and increased with the time on (P＜0.05); the level of TNFα increased from （14.25±1.01） ng/g to （23.83±1.43） ng/g （P＜0.01）； the intestinal DAO activity decreased from （1.70±0.36） U/mg to （1.22±0.41） U/mg （P＜0.01），and plasma DAO activity increased from （6.44±1.74）U/ml to （8.93±1.29） U/ml （P＜0.01）; the MPO activity increased from （2.85±1.22 ） U/mg to （4.93±1.37） U/mg （P＜0.01）. ConclusionThe ICAM-1 expression is significantly upregulated and the level of TNFα significantly increases after bile duct ligation, which may be involved in the PMNmediated injury to intestinal mucosa.
ObjectiveTo evaluate the effect of polymorphonuclear neutrophils (PMN) on liver damage in acute pancreatitis. MethodsSeventytwo wistar rats were randomly divided into acute pancreatitis (AP) group, acute pancreatitis with PMN depleted (APD) group and sham operation (SO) group. Liver damage was assessed by histological changes and the level of alanine aminotransferase (ALT) in serum. The number of PMN infiltration in liver was reflected by myeloperoxidase (MPO). ResultsMPO significantly increased from 6 to 24 hours in AP and APD groups. However, the level of MPO was significantly higher in AP group than that in APD group. ALT significantly increased from 3 to 24 hours in these two groups, but the level of ALT was significantly lower in APD group than that in AP group. Meanwhile, the hepatic pathological changes were more severe in AP group than that in APD group. ConclusionPMN play an important role in liver damage during acute pancreatitis.
The mumber of Polymorphonuclear leukocyte (PMN) in hepatic tissue increased in the rats with cholangitis, PMN infiltration was mainly in the hepatic sinus in the early stage; and PMN infiltration presented around the hepatocytes 12 hours after infection. Degeneration and necrosis of the hepatic cells was also observed in the rats with acute cholangitis. Only 40 percent of the rats survived 24 hours after infection. Depletion of circulating PMN decreased the damage and necrosis of hepatocytes and improving the survival rate of the infected rats. The results suggest that PMN infiltration plays an important role in hepatic damage in acute cholangitis.
Reduced chemotactic migration of polymorphonuclear neutrophil (PMN) in sepsis patients leads to decreased bacterial clearance and accelerates the progression of sepsis disease. Quantification of PMN chemotaxis in sepsis patients can help characterize the immune health of sepsis patients. Microfluidic microarrays have been widely used for cell chemotaxis analysis because of the advantages of low reagent consumption, near-physiological environment, and visualization of the migration process. Currently, the study of PMN chemotaxis using microfluidic chips is mainly limited by the cumbersome cell separation operation and low throughput of microfluidic chips. In this paper, we first designed an inertial cell sorting chip to achieve label-free separation of the two major cell types by using the basic principle that leukocytes (mainly granulocytes, lymphocytes and monocytes) and erythrocytes move to different positions of the spiral microchannel when they move in the spiral microchannel under different strength of inertial force and Dean's resistance. Subsequently, in this paper, we designed a multi-channel cell migration chip and constructed a microfluidic PMN inertial label-free sorting and chemotaxis analysis platform. The inertial cell sorting chip separates leukocyte populations and then injects them into the multi-channel cell migration chip, which can complete the chemotaxis test of PMN to chemotactic peptide (fMLP) within 15 min. The remaining cells, such as monocytes with slow motility and lymphocytes that require pre-activation with proliferative culture, do not undergo significant chemotactic migration. The test results of sepsis patients (n=6) and healthy volunteers (n=3) recruited in this study showed that the chemotaxis index (CI) and migration velocity (v) of PMN from sepsis patients were significantly weaker than those from healthy volunteers. In conclusion, the microfluidic PMN inertial label-free sorting and chemotaxis analysis platform constructed in this paper can be used as a new tool for cell label-free sorting and migration studies.