Methotrexate inhibits polymorphonuclear leucocyte chemotaxis in psoriasis

Area of Science:

• Immunology
• Dermatology
• Pharmacology

Background:

• Psoriasis is a chronic inflammatory skin condition.
• The role of polymorphonuclear leucocytes (PMN) in psoriasis pathogenesis is under investigation.
• Methotrexate (MTX) is a common treatment for psoriasis, but its effect on immune cell function requires further elucidation.

Purpose of the Study:

• To investigate the effect of low-dose methotrexate (MTX) on the chemotactic activity of peripheral polymorphonuclear leucocytes (PMN) in patients with widespread psoriasis.

Main Methods:

• Six patients with widespread psoriasis received intramuscular methotrexate (MTX) at 20 mg.
• Chemotactic activity of peripheral PMN was assessed before and after MTX treatment using the modified Boyden chamber method.
• Chemotaxins included C5a, FMLP, casein, and autologous fresh serum.

Main Results:

• Methotrexate (MTX) treatment resulted in a significant inhibition of PMN chemotactic migration, exceeding 50% inhibition for 2 days post-treatment.
• PMN function gradually recovered within 5 days following MTX administration.
• The inhibitory effect of MTX was observed across all four tested chemotaxins, indicating a broad impact on PMN function.

Conclusions:

• Low-dose methotrexate (MTX) profoundly inhibits PMN function in patients with psoriasis.
• These findings suggest that PMN play a significant role in the pathogenesis of psoriasis.
• Targeting PMN function could be a therapeutic strategy for psoriasis.