Search results for "Lewis X Antigen"
showing 10 items of 16 documents
The embryo-placental CD15-positive "vasculogenic zones" as a source of propranolol-sensitive pediatric vascular tumors.
2015
Abstract Objective Propranolol-induced involution is a unique biological feature of some pediatric vascular tumors, for instance infantile hemangioma (IH), cerebral cavernoma or chorioangioma. Currently, the cellular origin of these distinct tumors is unclear. In this study, we tested the hypothesis that propranolol-responsive vascular tumors are derived from common vessel-forming CD15 + progenitor cells which occur in early gestation. The aim of this study was to identify the tumor-relevant CD15 + progenitors at the early stages of embryo-placental development. Materials and methods Human embryo-placental units of 4–8 weeks gestation and pediatric vascular tumors were tested for expression…
Immaturity for gestational age of microvasculature and placental barrier in term placentas with high weight
2017
Abstract Objective Villous immaturity for gestational age is a multifactorial developmental deviation associated with unexpected placental insufficiency, fetal hypoxia and term fetal death. In our previous work we have shown that immature CD15+/CD31+/CD34+ endothelial cells were an important indicator of placental villous immaturity and chronic insufficiency. The aim of this study was to perform a comparative analysis of CD15-marked immaturity in the vessel walls between normal and pathological term placentas of clinically and structurally heterogenous groups with normal, low and high weight. Study design 165 clinically normal and pathological placentas of gestational age 39–42 with normal …
Specific norovirus interaction with Lewis x and Lewis a on human intestinal inflammatory mucosa during refractory inflammatory bowel disease
2021
Inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), are progressive diseases affecting millions of people each year. Flare-ups during IBD result in severe mucosal alterations of the small intestine (in CD) and in the colon and rectum (in CD and UC).
Transient CD15-positive endothelial phenotype in the human placenta correlates with physiological and pathological fetoplacental immaturity
2013
Abstract Objective Placental growth and villous maturation are critical parameters of placental function at the end of pregnancy. A failure in these processes leads to the development of placental dysfunction, as well as fetal and neonatal mortality and morbidity. The aim of the study was to determine the relevant diagnostic markers associated with pathological placental development. Study design Forty tissue samples from normal placentas of different gestational age and 68 pathological term placentas with defective villous maturation (GDM, idiopathic IUFD, preeclamsia, HELLP syndrome) comprised the comparative immunohistochemical study (CD15, CD45 and CD34). Positive immunohistochemical re…
CD15 immunostaining improves placental diagnosis of fetal hypoxia
2020
Fetal hypoxic events with unclear predictive value are a common indication for placenta examination. We evaluated whether the use of CD15 immunostaining can improve the assessment of severity and duration of fetal hypoxia.We compared placentas (37-42 gestational weeks) from stillborns/newborns with birth asphyxia (BA) and non-hypoxic newborns. Placental findings were studied in following groups: (1) acute BA (n = 11) due to placental abruption, (2) non-acute BA (n = 121) due to non-acute conditions, (3) non-BA (n = 46) in pregnancies with preeclampsia and gestational diabetes, and (4) controls (n = 30).A high expression of CD15 in feto-placental resistance vessels (FRVs) was present in non-…
Spacer-separated sialyl LewisX cyclopeptide conjugates as potential E-selectin ligands.
2006
Completely protected sialyl LewisX azide was synthesized from a neolactosamine azide precursor carrying a 3-O-allyloxycarbonyl group as the temporary protecting group. After its Pd(0)-catalyzed deprotection and stereoselective alpha-fucosylation, the obtained LewisX azide was subjected to O-deacetylation in the galactose unit and subsequent regio- and stereoselective sialylation. Reduction of the anomeric azido group afforded the sialyl LewisX amine building block. Two molecules of this tetrasaccharide ligand were conjugated to a preformed cyclooctapeptide containing two equidistant l-asparagine units equipped with carboxy-terminated tetraethyleneglycol side chains to give, after deprotecti…
Glycosyl azides as building blocks in convergent syntheses of oligomeric lactosamine and Lewisx saccharides
1997
Abstract Oligosaccharides containing type 2 lactosamine repeating units, e.g. neo-lacto-octaose and trimeric Lewis x derivatives, are constructed using neo-lactosamine azide building blocks. The azido group provides a favorable protection of the anomeric position which is stable to versatile protecting group manipulations and glycosylation reactions. On the other hand, glycosyl azides can be converted into glycosyl fluorides via a 1,3-dipolar cycloaddition with di- tert -butyl-acetylenedicar☐ylate and subsequent treatment of the resulting N -glycosyl triazoles with hydrogen fluoride-pyridine complex. Activation of the lactosamine fluorides with Lewis acids affords the possibility to extend …
L-asparaginase inhibits invasive and angiogenic activity and induces autophagy in ovarian cancer
2012
Recent work identified L-asparaginase (L-ASP) as a putative therapeutic target for ovarian cancer. We suggest that L-ASP, a dysregulator of glycosylation, would interrupt the local microenvironment, affecting the ovarian cancer cell-endothelial cell interaction and thus angiogenesis without cytotoxic effects. Ovarian cancer cell lines and human microvascular endothelial cells (HMVEC) were exposed to L-ASP at physiologically attainable concentrations and subjected to analyses of endothelial tube formation, invasion, adhesion and the assessment of sialylated proteins involved in matrix-associated and heterotypic cell adhesion. Marked reduction in HMVEC tube formation in vitro, HMVEC and ovari…
E-selectin modulates the malignant properties of T84 colon carcinoma cells.
2002
The extravasation of metastatic cells is regulated by molecular events involving the initial adhesion of tumor cells to the endothelium and subsequently the migration of cells in the host connective tissue. E-selectin on endothelial cells and sialyl Lewis X carbohydrate component on tumor cells are mainly involved in the adhesion of colon carcinoma cells to the endothelium of target organ. Interaction of T84 colon cancer cells to purified E-selectin in vitro caused an increase in the tyrosine phosphorylation of a number of proteins as well as the modulation of cellular properties correlated to the metastatic phenotype. Specifically, E-selectin-stimulated actin reorganization, increased coll…