Solid Lipid Nanoparticles: A Potential Multifunctional Approach towards Rheumatoid Arthritis Theranostics.

Area of Science:

• Nanomedicine
• Immunology
• Materials Science

Background:

• Rheumatoid arthritis (RA) is a severe autoimmune disease with poorly understood inflammation.
• Developing targeted and effective long-lasting therapies for RA remains a significant challenge.

Purpose of the Study:

• To develop a targeted theranostic system for rheumatoid arthritis (RA) using nanomedicine.
• To create a system for intravenous administration utilizing solid lipid nanoparticles (SLNs) functionalized with anti-CD64 antibodies.

Main Methods:

• Co-encapsulation of methotrexate (therapeutic) and superparamagnetic iron oxide nanoparticles (SPIONs, imaging) within SLNs.
• Surface functionalization of SLNs with anti-CD64 antibodies for macrophage targeting.
• Characterization of nanoparticle size, zeta potential, SPION encapsulation, and MTX association efficiency.
• In vitro cytotoxicity studies using THP-1 cells.

Main Results:

• Formulations exhibited sizes under 250 nm and zeta potential below -16 mV, suitable for intravenous administration.
• Transmission electron microscopy confirmed SPION encapsulation within the SLN matrix.
• Methotrexate association efficiency exceeded 98%.
• In vitro studies showed low cytotoxicity for the nanoparticles at concentrations below 500 μg/mL.

Conclusions:

• The developed nanoparticles are non-cytotoxic and capable of co-encapsulating therapeutic and imaging agents.
• Successful functionalization of SLNs with antibodies demonstrates potential for targeted delivery.
• These novel theranostic nanoparticles represent promising candidates for future RA treatment and diagnosis.