Syncytin-1/HERV-W envelope is an early activation marker of leukocytes and is upregulated in multiple sclerosis patients.

Abstract

Syncytin-1 is the envelope protein of the human endogenous retrovirus W (HERV-W). It has been related to multiple sclerosis (MS) but its role in cellular immunity and its pathogenic mechanism in the autoimmune context are not fully understood. We analyzed syncytin-1 levels in peripheral blood mononuclear cells (PBMC) subsets from healthy donors, MS patients in relapse or remission, and patients with acute infections by flow cytometry. PBMC cultures were also prepared to analyze protein expression kinetics. MS patients had higher levels of syncytin-1 levels than controls. We found that syncytin-1 is elevated in monocytes during MS relapses and infections. Cells expressing syncytin-1, including monocytes, T and B lymphocytes, and NKs presented mainly an activated phenotype and, upon stimulation with LPS, its levels increased rapidly on antigen-presenting cells. Syncytin-1 ligation promoted the activation of monocytes, as demonstrated by the upregulation of CD80 and the nonclassical subset CD14low CD16+ . Our results suggest an important role for syncytin-1 in the activation of leukocytes. Given that the expression of syncytin-1 is upregulated in MS patients, this protein might be contributing to the autoimmune cascade in the disease.

• Authors: Marta Garcia-Montojo, Eulalia Rodriguez-Martin, Priscila Ramos-Mozo, Isabel Ortega-Madueño, Maria Inmaculada Dominguez-Mozo, Ana Arias-Leal, Maria Ángel García-Martínez, Ignacio Casanova, Victoria Galan, Rafael Arroyo, Roberto Álvarez-Lafuente, Luisa María Villar
• Journal: European journal of immunology (Eur J Immunol) Vol. 50 Issue 5 Pg. 685-694 (05 2020) ISSN: 1521-4141 [Electronic] Germany
• PMID: 32012247 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical References

• B7-1 Antigen
• CD14 protein, human
• CD80 protein, human
• FCGR3B protein, human
• GPI-Linked Proteins
• Gene Products, env
• Lipopolysaccharide Receptors
• Lipopolysaccharides
• Pregnancy Proteins
• Receptors, IgG
• syncytin

Topics

• Adult
• B-Lymphocytes (drug effects, immunology, virology)
• B7-1 Antigen (genetics, immunology)
• Case-Control Studies
• Endogenous Retroviruses (genetics, immunology)
• Female
• GPI-Linked Proteins (genetics, immunology)
• Gene Expression Regulation
• Gene Products, env (genetics, immunology)
• Humans
• Killer Cells, Natural (drug effects, immunology, virology)
• Lipopolysaccharide Receptors (genetics, immunology)
• Lipopolysaccharides (pharmacology)
• Male
• Middle Aged
• Monocytes (drug effects, immunology, virology)
• Multiple Sclerosis (genetics, immunology, pathology, virology)
• Pregnancy Proteins (genetics, immunology)
• Primary Cell Culture
• Receptors, IgG (genetics, immunology)
• Recurrence
• Remission Induction
• Signal Transduction
• T-Lymphocytes (drug effects, immunology, virology)