Upregulated selenoprotein I during lipopolysaccharide-induced B cell activation promotes lipidomic changes and is required for effective differentiation into IgM-secreting plasma B cells.
J Leukoc Biol
; 116(1): 6-17, 2024 Jun 28.
Article
de En
| MEDLINE
| ID: mdl-38289835
ABSTRACT
The mechanisms driving metabolic reprogramming during B cell activation are unclear, particularly roles for enzymatic pathways involved in lipid remodeling. We found that murine B cell activation with lipopolysaccharide (LPS) led to a 1.6-fold increase in total lipids that included higher levels of phosphatidylethanolamine (PE) and plasmenyl PE. Selenoprotein I (SELENOI) is an ethanolamine phospholipid transferase involved in the synthesis of both PE and plasmenyl PE, and SELENOI expression was also upregulated during activation. Selenoi knockout (KO) B cells exhibited decreased levels of plasmenyl PE, which plays an important antioxidant role. Lipid peroxidation was measured and found to increase â¼2-fold in KO vs. wild-type (WT) B cells. Cell death was not impacted by KO in LPS-treated B cells and proliferation was only slightly reduced, but differentiation into CD138 + Blimp-1+ plasma B cells was decreased â¼2-fold. This led to examination of B cell receptors important for differentiation that recognize the ligand B cell activating factor, and levels of TACI (transmembrane activator, calcium-modulator, and cytophilin ligand interactor) (CD267) were significantly decreased on KO B cells compared with WT control cells. Vaccination with ovalbumin/adjuvant led to decreased ovalbumin-specific immunoglobulin M (IgM) levels in sera of KO mice compared with WT mice. Real-time polymerase chain reaction analyses revealed a decreased switch from surface to secreted IgM in spleens of KO mice induced by vaccination or LP-BM5 retrovirus infection. Overall, these findings detail the lipidomic response of B cells to LPS activation and reveal the importance of upregulated SELENOI for promoting differentiation into IgM-secreting plasma B cells.
Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Immunoglobuline M
/
Lymphocytes B
/
Activation des lymphocytes
/
Différenciation cellulaire
/
Lipopolysaccharides
/
Sélénoprotéines
Limites:
Animals
Langue:
En
Journal:
J Leukoc Biol
Année:
2024
Type de document:
Article
Pays d'affiliation:
États-Unis d'Amérique