Ureaplasma isolates differentially modulate growth factors and cell adhesion molecules in human neonatal and adult...

Area of Science:

• Immunology
• Microbiology
• Neonatal Research

Background:

• Ureaplasma is typically considered commensal, but its role in inflammation-related diseases is debated.
• Previous research indicated Ureaplasma can trigger pro-inflammatory cytokine responses in human monocytes.
• The specific inflammatory mediators induced by Ureaplasma in different monocyte populations require further investigation.

Purpose of the Study:

• To investigate Ureaplasma's capacity to induce inflammatory mediators, specifically granulocyte-colony stimulating factor (G-CSF), vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1).
• To compare the responses in term neonatal and adult human monocytes upon exposure to Ureaplasma urealyticum serovar 8 (Uu8) and U. parvum serovar 3 (Up3).
• To explore the dose-dependency and potential synergistic effects with lipopolysaccharide (LPS) on Ureaplasma-induced inflammatory responses.

Main Methods:

• Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to assess mRNA expression levels.
• Multi-analyte immunoassay was employed to measure protein secretion.
• Neonatal and adult monocytes were exposed to Ureaplasma isolates (Uu8, Up3) and Escherichia coli lipopolysaccharide (LPS) in vitro, with varying concentrations and co-infection models.

Main Results:

• Ureaplasma significantly induced VEGF mRNA in both neonatal and adult monocytes, and ICAM-1 mRNA in neonatal monocytes.
• Protein analysis revealed Ureaplasma stimulated VEGF release in both age groups and enhanced ICAM-1 secretion in neonatal and adult monocytes.
• Ureaplasma-induced inflammatory responses were dose-dependent and comparable to LPS stimulation; co-infection with LPS-primed monocytes amplified ICAM-1 release.

Conclusions:

• Ureaplasma actively drives pro-inflammatory responses in human monocytes, modulating specific growth factors and cell adhesion molecules.
• These findings suggest Ureaplasma infection can contribute to unbalanced monocyte behavior and adverse immunomodulation, particularly in neonatal settings.
• The study underscores the clinical relevance of Ureaplasma in inflammatory pathogenesis, challenging its traditionally low pathogenic perception.