Immunoglobulin isotype isolated from human placental extract does not interfere in complement-mediated bacterial opsonization within the wound milieu

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Human placental extract has many applications as a wound healer.

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Immunoglobulin G is a key glycoprotein present in human placental extract.

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Placental IgG (25.2 ± 3.97 μg/ml) did not exert anti-complementary effects.

The wound healing potency of an aqueous extract of placenta can be evaluated through the presence of numerous regulatory components. The presence of glycans was detected by thin layer chromatography and fluorophore-assisted carbohydrate electrophoresis. Mass spectrometric analysis revealed the existence of multiple fragments of immunoglobulin G (IgG). IgG was present in the extract at a concentration of 25.2 ± 3.97 μg/ml. IgG possesses anti-complementary activity by diverting the complement activation from target surface. Thus, effect of placental IgG on complement–bacteria interaction was investigated through classical and alternative pathway and the preparation was ascertained to be safe with respect to their interference in the process of bacterial opsonization.

N-Glycosylation of extracellular matrix protein 1 (ECM1) regulates its secretion, which is unrelated to lipoid proteinosis

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Extracellular matrix protein 1 (ECM1) plays roles in extracellular matrix formation.

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Two ECM1 gene mutations observed in lipoid proteinosis patients suppress its secretion.

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ECM1 is N-glycosylated at Asn³⁵⁴ and Asn⁴⁴⁴ residues.

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N-linked glycan at Asn³⁵⁴ negatively regulated secretion of ECM1.

Extracellular matrix protein 1 (ECM1) is expressed in a wide variety of tissues and plays important roles in extracellular matrix formation. Additionally, ECM1 gene mutations cause lipoid proteinosis (LP), a rare skin condition of genetic origin. However, an effective therapeutic approach of LP is not established. Here, we showed that ECM1 gene mutation observed in LP patients significantly suppresses its secretion. As ECM1 has three putative N-glycosylation sites and most of mutated ECM1 observed in LP patients are defective in these N-glycosylation sites, we investigated the correlation between LP and N-glycosylation of ECM1. We identified that the Asn³⁵⁴ and Asn⁴⁴⁴ residues in ECM1 were N-glycosylated by mass spectrometry analysis. In addition, an N-linked glycan at Asn³⁵⁴ negatively regulated secretion of ECM1, contrary to LP patient-derived mutants. These results indicate that the defect of N-glycosylation in ECM1 is not involved in the aberration of secretion of LP-derived mutated ECM1.