ANTIPHOSPHOLIPID SYNDROME AND MONOCYTES: NEW ASPECTS

Area of Science:

• Immunology
• Molecular Biology
• Pathogenesis of Autoimmune Diseases

Background:

• Antiphospholipid syndrome (APS) pathogenesis involves monocytes, but their activation mechanisms remain unclear.
• Monocyte activation is implicated in both thrombotic and non-thrombotic APS complications.

Purpose of the Study:

• To investigate the transcriptional activity of monocytes from APS patients upon stimulation with lipopolysaccharide (LPS) and LPS+ATP.
• To identify molecular pathways involved in monocyte activation in APS.

Main Methods:

• Comparative RT-PCR analysis of monocyte gene expression.
• Study included eleven women with APS and recurrent miscarriages and nine healthy women as controls.
• Monocytes were exposed to low concentrations of LPS and LPS+ATP.

Main Results:

• APS monocytes exhibited elevated mRNA levels of TLR2, IL-23, CCL2, CXCL10, IL-1β, and IL-6 after LPS stimulation.
• Healthy monocytes showed increased IL-6 and STAT3 mRNA with LPS.
• Dual stimulation (LPS+ATP) decreased CCL-2, IL-1β, and NLRP3 mRNA in APS cells but elevated TLR2 mRNA in both groups.

Conclusions:

• Increased monocyte sensitivity to LPS in APS may contribute to thrombus formation.
• Low concentrations of ATP may mitigate the LPS-induced inflammatory state in APS monocytes, indicating a potential regulatory pathway.