건선환자의 말초혈액 내 CD4+CD25+Foxp3+ 조절 T 세포와 CD4+CD25-Foxp3+ T 세포 수에 관한 연구

Abstract

Background: Regulatory T cells (Treg) are able to inhibit the immunological response and to maintain the cutaneous immunological homeostasis, thus preventing autoimmunity against itself. In several studies, the importance of CD4+CD25+Foxp3+ Treg in psoriasis has examined in the peripheral blood of patients. But, limited studies on Treg are available and give conflicting results. Recently, CD4+CD25-Foxp3+ T cells have been intrigued as peripheral reservoir of CD4+CD25+Foxp3+ Treg.

Objective: To investigate differences in the CD4+CD25+Foxp3+ Treg and CD4+CD25-Foxp3+T cells count between patients with psoriasis and normal controls

Methods: For phenotypic analysis, proportions and absolute cell numbers of CD4+CD25+Foxp3+ Treg and CD4+CD25-Foxp3+T cells in peripheral blood were examined by flow cytometry in psoriasis patients(n=19) and age-matched healthy controls(n=14). The correlation between CD4+CD25+Foxp3+ Treg count and the other parameters, such as age of onset, disease duration, BSA, PASI score and clinical stage in psoriasis patients was also analyzed.

Results: Although CD4+CD25+Foxp3+ Treg count was increased slightly in peripheral blood of psoriasis patients compared with controls, the difference was not statistically significant(5.27±2.60 vs. 4.70±1.35, p>0.05). And the number of CD4+CD25-Foxp3+ T cells was decreased slightly in psoriasis, but there was also no significant difference(1.56±1.07 vs. 1.93±1.08, p>0.05). CD4+CD25+Foxp3+ Treg count was not correlated with any parameter except clinical stage of psoriasis. Mean±numbers of CD4+CD25+Foxp3+ Tregin stable phase was higher than in progressive phase(7.26±2.58 vs. 4.35±2.10, p<0.05). CD4+CD25-Foxp3+ T cell count did not show any significant correlation with all parameters( p>0.05).

Conclusion: These findings suggest that only CD4+CD25+Foxp3+ Tregcount is insufficient to explain the pathogenesis and severity of psoriasis. But a decrease of circulating CD4+CD25+Foxp3+ Treg is likely to correlated with aggravation of psoriasis.

Key word: CD4+CD25+Foxp3+ regulatory T cell, CD4+CD25-Foxp3+ T cell, psoriasis