Sialic acids as important molecules in the regulation of the immune system: pathophysiological implications of sialidases in immunity

Pilatte, Yannick; Bignon, J; Lambré, Claude

doi:10.1093/glycob/3.3.201

Cited by 153 publications

(84 citation statements)

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“…The study population was previously been described in detail. 15 Of 310 participants, 11 women (4%) were lost to follow-up, 12 women (4%) were excluded because of major congenital anomalies or higher-order multiple gestation, 8 women (3%) refused speculum examination, 17 women (5%) had the speculum examination omitted because of imminent delivery, and 44 women (14%) did not have sufficient vaginal fluid for analysis. The remaining 218 subjects had vaginal fluid samples available for these analyses.…”

Section: Methodsmentioning

confidence: 99%

“…1,2 We also confirmed that pregnant women with BV or intermediate flora have higher concentrations of sialidase and prolidase, two microbial hydrolytic enzymes that are produced by BV-associated bacteria, than do women with normal vaginal flora. In addition, pregnant women with BV or intermediate flora appear to have lower anti-Gvh 15 In addition, desialylation can alter the mucin plug both by altering the charge potential of glycoproteins and by favoring further degradation by proteases. 16 Persistent sialidase activity after antibiotic treatment in pregnant women was associated with an increased risk of preterm birth in one cohort.…”

Section: Commentmentioning

confidence: 99%

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Vaginal hydrolytic enzymes, immunoglobulin A against Gardnerella vaginalis toxin, and risk of early preterm birth among women in preterm labor with bacterial vaginosis or intermediate flora

Cauci¹,

Hitti²,

Noonan³

et al. 2002

American Journal of Obstetrics and Gynecology

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Bacterial vaginosis (BV) is characterized by a shift in vaginal flora, with a decrease in the prevalence of Lactobacillus and an increase in the prevalence and concentration of anaerobic bacteria, Gardnerella vaginalis, and Mycoplasma hominis. BV, which is consistently associated with preterm delivery, 1,2 is also associated with first-and second-trimester miscarriage, 3,4 amniotic fluid infection, 5,6 histologic chorioamnionitis, 7 and postpartum endometritis. 8 The consistent associations between BV and these markers of upper genital tract infection provide strong indirect evidence that abnormal vaginal flora can ascend to cause bacterial upper genital tract infection and preterm birth. However, most pregnant women with BV have normal pregnancy outcomes.The presence and concentrations of microbial hydrolytic enzymes in women with BV vary. Sialidases (or neuraminidases) are glycosylases that are produced in vitro by several BV-associated bacteria. 9 Prolidase (or proline aminopeptidase) is another hydrolytic enzyme produced by BV-associated bacteria, including G vaginalis and Mobiluncus spp. 10 The only characterized immunogenic virulence factor found in BV thus far is the G vaginalis hemolytic toxin (Gvh). 11,12 The production and concentration of immunoglobulin A (IgA) in response to Gvh in women with BV also vary. Low levels of anti-Gvh IgA in women with BV who are not pregnant are correlated with high levels of vaginal sialidase activity 13 and with cleavage of IgA in vaginal fluid. 14 It remains to be established whether different profiles of these biochemical markers correspond to different levels of risk for poor pregnancy outcome. In the present study, we examined the hypothesis that an increased concentration of sialidase and prolidase and a decreased con- Udine, Italy, Seattle, Wash, and Pittsburgh, Pa OBJECTIVE: The purpose of this study was to determine whether the microbial hydrolytic enzymes, sialidase and prolidase, and immunoglobulin A against the Gardnerella vaginalis cytolysin (anti-Gvh IgA) increase the risk for early preterm birth (≤34 weeks of gestation) among women with bacterial vaginosis or intermediate flora. STUDY DESIGN:Two hundred eighteen afebrile women in preterm labor with intact membranes had a vaginal Gram stain performed, and sialidase, prolidase, and anti-Gvh IgA concentrations were determined. RESULTS: Women with bacterial vaginosis or intermediate flora had significantly higher sialidase and prolidase concentrations than women with normal flora. Among women with bacterial vaginosis or intermediate flora, the women with sialidase had a higher rate of early preterm birth (P = .05). Sialidase had a sensitivity of 43% and specificity of 77% for early preterm birth. Prolidase and anti-Gvh IgA did not predict early preterm birth. CONCLUSION: Women in preterm labor with bacterial vaginosis or intermediate flora and detectable sialidase are at increased risk of early preterm birth. (Am J Obstet Gynecol 2002;187:877-81.)

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Section: Methodsmentioning

confidence: 99%

Section: Commentmentioning

confidence: 99%

Vaginal hydrolytic enzymes, immunoglobulin A against Gardnerella vaginalis toxin, and risk of early preterm birth among women in preterm labor with bacterial vaginosis or intermediate flora

Cauci¹,

Hitti²,

Noonan³

et al. 2002

American Journal of Obstetrics and Gynecology

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“…COS-1 cells were obtained from the RIKEN Cell Bank. They were grown in DMEM supplemented with 10% FBS in 5% CO 2 . Cells in the exponential growth phase within four passages were used for this investigation.…”

Section: Cell Linesmentioning

confidence: 99%

“…Desialylation of these glycoconjugates is a crucial event leading to modulation of cellular functions in numerous physiological and pathological processes. 1,2 Alterations in sialylation during malignant transformation have been observed to be closely associated with the malignant phenotype in terms of metastatic potential and invasiveness. [3][4][5][6][7] To understand how sialidases are involved in this aberrant sialylation, our study has focused on mammalian forms in cancer cells.…”

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confidence: 99%

Overexpression of lysosomal-type sialidase leads to suppression of metastasis associated with reversion of malignant phenotype in murine B16 melanoma cells

et al. 2001

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Increased sialylation in cell surface glycoproteins is one characteristic feature of cancer cells, particularly related to their metastatic potential and invasiveness. Expression of lysosomal-type sialidase, which plays a major role in hydrolysis of such sialo-glycoproteins, is therefore considered to have a great influence on malignant properties of cancer cells. To investigate whether the sialidase expression level is linked to the malignant phenotype, we transfected B16-BL6 murine melanoma cells, a highly invasive and metastatic line, with an expression vector harboring a rat lysosomal sialidase cDNA; then clones were isolated and examined for changes in biological character. Sialidase-overexpressing cells showed suppression of experimental pulmonary metastasis and tumor progression. The transfectants exhibited diminished cell growth, anchorage-independent growth and increased sensitivity to apoptosis induced by suspension culture or serum depletion in vitro, but no significant alterations in invasiveness, cell motility and cell attachment to fibronectin, collagen IV and laminin. Flow cytometric analysis with either peanut agglutinin (PNA) or Ricinus communis agglutinin (RCA) lectin revealed that desialylated forms of glycoproteins on the cell surfaces were increased. In particular, a desialylated form of a cell surface glycoprotein of 83 kDa was prominent in the transfectants, as determined by galactose oxidase labeling. These observations indicate that sialidase expression is inversely associated with metastatic potential and tumor growth in cancer cells, probably through a regulation mechanism that suppresses cell growth and anchorage-independent growth and promotes apoptosis with deprivation of cell anchorage. © 2001 Wiley-Liss, Inc. Key words: sialidase; metastasis; anchorage-independent growth; sialic acidsSialidase (EC 3.2.1.18) is a key enzyme in catabolism of glycoproteins and glycolipids. Desialylation of these glycoconjugates is a crucial event leading to modulation of cellular functions in numerous physiological and pathological processes. 1,2 Alterations in sialylation during malignant transformation have been observed to be closely associated with the malignant phenotype in terms of metastatic potential and invasiveness. [3][4][5][6][7] To understand how sialidases are involved in this aberrant sialylation, our study has focused on mammalian forms in cancer cells.Mammalian sialidases are classified into 3 to 4 forms based on their subcellular localization and substrate preference. Cytosolic, lysosomal and membrane forms of the sialidases have been cloned; their primary sequences revealed that they are proteins encoded by distinct genes with different major subcellular locations and enzymatic properties. 8 We previously demonstrated that metastatic potential is inversely correlated with lysosomal-type sialidase activity in transformed rat 3Y1 cells 9 and in murine B16 melanoma cells, 10 whereas it did not have a significant relation to sialic acid levels. We also investigated the role of sialidas...

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“…Sialic acids that cover the cell surface as the terminals of glycosylation were previously demonstrated to play various roles in the regulation of immune responses (Pilatte et al 1993). Although sialic acids are generally rare in lower organisms, some pathogens possess sialic acids on their surface, which may be in an attempt to evade immune responses by mimicking host cells.…”

Section: Introductionmentioning

confidence: 99%

Enhanced lentiviral vector production in 293FT cells expressing Siglec-9

et al. 2014

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Siglecs, sialic acid-recognizing Ig-superfamily lectins, regulate various aspects of immune responses, and have also been shown to induce the endocytosis of binding materials such as anti-Siglec antibodies or sialic acid-harboring bacteria. In this study, we demonstrated that the expression of Siglec-9 enhanced the transfection efficiency of several cell lines such as macrophage RAW264 and non-hematopoietic 293FT cells. We applied this finding to the production of a lentiviral vector in which cells were transfected simultaneously with multiple vectors, and achieved a twice increase in viral production levels. Furthermore, 293FT cells expressing lectin-defective Siglec-9 produced threeto seven-fold higher titer of viral vector compared with parental 293FT cells. These results suggest that Siglec-9 enhanced lentiviral vector production in a lectin-independent manner.

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Sialic acids as important molecules in the regulation of the immune system: pathophysiological implications of sialidases in immunity

Cited by 153 publications

References 0 publications

Vaginal hydrolytic enzymes, immunoglobulin A against Gardnerella vaginalis toxin, and risk of early preterm birth among women in preterm labor with bacterial vaginosis or intermediate flora

Vaginal hydrolytic enzymes, immunoglobulin A against Gardnerella vaginalis toxin, and risk of early preterm birth among women in preterm labor with bacterial vaginosis or intermediate flora

Overexpression of lysosomal-type sialidase leads to suppression of metastasis associated with reversion of malignant phenotype in murine B16 melanoma cells

Enhanced lentiviral vector production in 293FT cells expressing Siglec-9

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