Effect of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of adhesion molecules on human neutrophils

The effects of linoleic acid, linoleic acid anilide, and arachidonic acid on the expression of CD11b/CD18, CD11c/CD18 integrins and l-selectin on human neutrophils were studied by flow cytometry in a whole blood assay. None of these compounds had any effect on the basal expression of CD11b, CD11c, or l-selectin in the concentration range of 20–100 μM. However, linoleic acid at a concentration of 1000 μM slightly up-regulated CD11b and CD11c by a factor of 2.1 and 1.7, respectively. Linoleic acid, linoleic acid anilide, and arachidonic acid did not affect the formyl-methionyl-leucyl-phenylalanine induced up-regulation of CD11b or CD11c. However, linoleic acid and linoleic acid anilide slightly inhibited the phorbol myristate acetate (PMA)-induced expression of CD11b, which was decreased by 27 and 21% at concentrations of 100 and 1000 μM, respectively. Likewise, arachidonic acid at 40 μM inhibited the PMA-induced expression of CD11b by 19%. Our results suggest that linoleic acid, linoleic acid anilide, and arachidonic acid do not dramatically affect the expression of leukocyte adhesion molecules in a whole blood assay. Received: 17 February 1997  / Accepted: 5 May 1997     

脑水肿对大鼠血脑屏障内皮细胞膜表面ICAM—1表达量的影响

采用液氮冷冻Ｗｉｓｔａｒ大鼠－侧大脑制成血管源性脑水肿模型，将大怀脑冷冻中心制成冠状面冰冻切片，运用免疫组化染色观察脑水肿组及对照组白质脑屏障内皮细胞表面ＩＣＡＭ－１蛋白表达量的变化 。     

Adhesion inhibitory activity of β-lactoglobulin isolated from infant formulae

β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis.     

Localization of adhesion molecules on human spermatozoa by fluorescence microscopy

Summary.  The expression of adhesion molecules on human spermatozoa of healthy probands was analysed. The localization patterns of adhesion molecules (AM) on the spermatozoal surface were documented by fluorescence microscopy. Spermatozoa were incubated with antibodies against α1 (CD49a), α2 (CD49b), α3 (CD49c), α4 (CD49d), α5 (CD49e), α6 (CD49f) chains of β1 integrins, β1 (CD29), β2 (CD18), αV (CD51), β3 (CD61) and β4 integrin chains, the LFA-3 (Lymphocyte function antigen, CD58) from the immunoglobulin superfamily and the extracellular matrix proteins laminin, fibronectin and collagen IV. For collagen IV, α1 and α2 chains no expression could be noticed. Laminin was detected at the acrosomal membrane, fibronectin and β4 chain mainly at the equatorial membrane. The fibronectin receptors α3, α4 and α5 chains of the β1 integrins were mainly located on acrosomal and equatorial membrane areas. Laminin receptor α6 chain was located postacrosomal and less frequently acrosomal. β2 chain and vitronectin receptors αV and β3 chains had a mainly postacrosomal localization pattern. LFA-3 was found constantly on postacrosomal membrane areas. Double staining technique was used to prove the simultaneous occurrence of fibronectin and its integrin receptors α3, α4 and α5 chains and of αV and β2 chains on spermatozoa. The localization patterns of integrins on double stained spermatozoa were similar to the patterns described for single stained spermatozoa. The localization of fibronectin appeared to be influenced by the presence of integrins: the typical equatorial fibronectin band disappeared in case of an equatorial localization of integrins.     

Cell-associated adhesion molecules as early markers of bioincompatibility

BACKGROUND.: Transient nature of adhesive interactions occurring during cellmargination is mainly dependent on expression of selectins whichare shed by activated cells. This shedding in the circulationmay play an important role as anti-inflammatory mediator. Haemodialysisis also associated with P-selectin (CD62P)/sialyl-Lewisx (CD15s)interactions which mediate platelet-leukocyte coaggregation.We further investigated the mechanisms underlying leukocytemargination during haemodialysis. METHODS.: CD15s, CD11b and CD61 expression on circulating leukocytes frompatients dialysed on synthetic membranes (modified polyacrylonitrile(SPAN), polysulphone (PS), and polyacrylonitrile (AN69) wasassessed by cytofluorometry in a prospective crossover trial.We measured plasma levels C3a/C3a desArg, soluble CD62P, andCD62E molecules obtained from patients and healthy individuals. RESULTS.: Expression of CD11b and CD15s was upregulated on neutrophilsfrom patients dialysed with SPAN and PS membranes during thedialysis session. A significant negative correlation was foundbetween the expression of CD11b or CD15s molecules and neutrophilcounts as well as between CD15s expression and monocyte countsduring haemodialysis. As assessed by CD61 expression on leukocytes,we observed that platelets bound significantly onto both neutrophilsand monocytes during dialysis with both membranes. A significantpositive correlation was found between the expression of CD11bmolecules and the percentage of CD61 ⁺ monocytes counts duringSPAN and PS dialysis. We found a significant increase of solubleCD62P in plasma samples obtained from haemodialysed patientsbefore the dialysis session as compared to the levels detectedin plasma from healthy individuals. CONCLUSIONS.: This study documents a major role of CD15s, CD11b, CD61, CD62Pmolecules in the transient leukocytes activation and marginationduring haemodialysis on synthetic membranes despite their lowcomplement-activating properties.     

体外丹参、藻酸双酯钠对脑血栓形成患者红细胞与内皮细胞粘附的影响

丹参、藻酸双酯钠是临床治疗脑血管病的常用药。本研究发现，在体外流场中用丹参、藻酸双酯钠分别处理脑血栓形成病人的红细胞后，此红细胞与培养的人脉静脉内皮细胞的粘附数目明显减少、粘附强度明显减弱；而且，在临床常用剂量下藻酸双酯钠的这种抗粘附作用优于丹参。认为丹参、藻酸双酯钠的这种抗粘附作用可能是临床用以治疗脑血栓形成的一个重要机理。     

Treatment with combined oral contraceptives induces a rise in serum C-reactive protein in the absence of a general inflammatory response

BACKGROUND: The role of inflammation in the pathogenesis of cardiovascular disease is well established. C-reactive protein (CRP) is the strongest independent predictor of myocardial infarction and stroke in women. Recent studies have indicated that CRP levels are raised during use of combined oral contraceptives (COCs). OBJECTIVES: The aim of the study was to investigate the effect of COCs on serum CRP levels and to indicate the underlying mechanisms of an expected increase. METHOD: In a prospective randomized cross over-study 35 women used two different preparations of COC, one second and one third generation. Serum levels of CRP, serum amyloid A (SAA), interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), antibodies against oxidized LDL, insulin and insulin-like growth factor-I (IGF-I) along with insulin-like growth factor binding protein-1 (IGFBP-1) and IGFBP-3 were analyzed before and during the two treatments. E-selectin, von Willebrand factor and factor VIII concentrations in plasma were also measured. RESULTS: A rise in serum CRP was observed during both treatments; the median level increased from 0.45 mg L(-1) at baseline to 1.48 mg L(-1) with second generation and to 2.02 mg L(-1) with third generation COC. The serum levels of SAA increased slightly during treatment with the third generation COC. IL-6 and TNFalpha were unaffected by treatment. Both preparations lowered IGF-I and raised IGFBP-1 and IGFBP-3 concentrations. CONCLUSION: The raised serum CRP concentration during treatment with COCs appears to be related to a direct effect on hepatocyte CRP synthesis and does not reflect IL-6 mediated inflammation, endothelial activation or induction of insulin resistance.     

抑肽酶对瓣膜置换术患者心肌粘附分子表达及细胞凋亡的影响

目的探讨抑肽酶对二尖瓣置换术患者围体外循环（CPB）期心肌细胞及心肌血管内皮细胞上细胞间粘附分子-1（ICAM-1）、血管细胞粘附分子-1（VCAM-1）表达及心肌细胞凋亡的影响。方法择期二尖瓣置换术患者30例,年龄24～59岁,体重46～73 kg,心功能分级Ⅱ级或Ⅲ级,随机分为2组（n=15）：对照组和抑肽酶组,抑肽酶组于CPB转机前,预充液中加入抑肽酶300万KIU,对照组则给予等容量生理盐水,分别于CPB前和CPB停止时取右心房心肌组织标本,采用免疫组织化学SP法染色,检测心肌细胞和心肌血管内皮细胞上ICAM-1、VCAM-1的表达,采用病理图像分析系统对ICAM-1、VCAM-1表达的灰度值作定量分析,采用TUNEL法检测凋亡心肌细胞。结果抑肽酶组CPB停止时ICAM-1、VCAM-1的表达低于对照组（P〈0.01）;2组CPB停止时心肌细胞凋亡指数较CPB前增高（P〈0.05）,抑肽酶组CPB停止时心肌细胞凋亡指数低于对照组（P〈0.05）。结论预充液中加入抑肽酶300万KIU可抑制二尖瓣置换术患者CPB期间心肌细胞和心肌血管内皮细胞ICAM-1、VCAM-1的表达及心肌细胞的凋亡。     

Fibrinogen promotes monocyte adhesion via a protein kinase C dependent mechanism

The accumulation of blood monocytes at sites of predilection of the vessel wall is an early cellular event of atherogenesis. Proteins of the vessel wall may facilitate monocyte adhesion and thus promote their recruitment. It has been shown that the relative content of extracellular fibrinogen increases during lesion development, and this study investigated the contribution of immobilized fibrinogen to monocyte adhesion and the underlying mechanism. Freshly isolated human blood monocytes were cultivated in serum-free RPMI 1640 in tissue culture wells precoated with albumin, fibrinogen, or fibrin. After 16 h the plates were washed and adherent cells enumcrated. Immobilized fibrinogen enhanced monocyte adhesion more than 1.9-fold compared to immobilized albumin or fibrin (P<0.05). Concomitant addition of the protein kinase C (PKC) inhibitors staurosporine or H7 suppressed monocyte adherence to immobilized fibrinogen but exerted no significant effect upon adhesion to any other surface tested. Stimulation of monocytes using phorbol myristate acetate resulted in increased binding of monocytes on fibrinogen but not on bovine serum albumin. When PKC activity was reduced through prolonged incubation with PMA for 16h, a significant reduction of monocyte adhesion on fibrinogen was observed. Peptides containing RGD sequences, which have been demonstrated to be ligands for certain integrins, did not inhibit monocyte adhesion. The data suggest that fibrinogen promotes monocyte adhesion in vitro by a PKC-dependent mechanism. PKC appears to be important not only for the initial cell adhesion but also for sustained binding of monocytes to fibrinogen.Abbreviations BSA Bovine serum albumin - ECM Extracellular matrix - PKC Protein kinase C - PMA Phorbol myristate acetate