Psoriasis vulgaris (PsV) is an immune-mediated inflammatory disorder with devastating psychosocial consequences. Expression of immunoregulator molecules on leukocytes in PsV remains unclear. Leukocyte-associated Ig-like receptor-1 (LAIR-1) and complement receptor-1 (CR-1) are immunoregulator receptors reported to bind complement component 1q involved in phagocytosis. We aimed to explore if altered leukocyte expression of LAIR-1 and CR-1 is associated with PsV. This case–control study included 36 PsV patients and 36 healthy controls. Neutrophils, monocytes and B and T cells were examined by flow cytometry for LAIR-1 and CR-1 mean fluorescence intensity (MFI) and positive cell percentage. Comparison between both groups revealed a significant decrease in LAIR-1 MFI on neutrophils and T cells (P < 0.001 and P = 0.003, respectively). CR-1 MFI on neutrophils, monocytes and T cells also showed a significant decrease in patients (P = 0.033, P = 0.001 and P = 0.040, respectively). There was a significant positive correlation of LAIR-1 MFI on neutrophils with CR-1 MFI on neutrophils (r = 0.503; P = 0.002) and LAIR-1 MFI on monocytes with CR-1 MFI on monocytes (r = 0.371; P = 0.026). Receiver operating characteristic curves revealed that CR-1 MFI on monocytes had the highest discrimination power to differentiate patients from controls, with 86.1% specificity and 75% sensitivity (P = 0.001). In conclusion, altered leukocytes expression of LAIR-1 and CR-1 is associated with PsV. Down-regulated CR-1 MFI on monocytes is a promising diagnostic biomarker for PsV.

寻常型银屑病(PsV) 是一种免疫介导的炎症性疾病，具有破坏性的心理社会后果。PsV 白细胞上免疫调节分子的表达仍不清楚。白细胞相关 Ig 样受体 1 (LAIR-1) 和补体受体 1 (CR-1) 是免疫调节受体，据报道可结合参与吞噬作用的补体成分 1q。我们旨在探讨 LAIR-1 和 CR-1 的白细胞表达改变是否与 PsV 相关。该病例对照研究包括 36 名 PsV 患者和 36 名健康对照。通过流式细胞术检查中性粒细胞、单核细胞以及 B 和 T 细胞的 LAIR-1 和 CR-1 平均荧光强度 (MFI) 和阳性细胞百分比。两组之间的比较显示，中性粒细胞和 T 细胞上的 LAIR-1 MFI 显着降低（P < 0.001 和P  = 0.003，分别）。中性粒细胞、单核细胞和 T 细胞上的 CR-1 MFI 在患者中也显示出显着降低（分别为P  = 0.033、P  = 0.001 和P  = 0.040）。中性粒细胞上的 LAIR-1 MFI 与中性粒细胞上的 CR-1 MFI ( r  = 0.503; P  = 0.002) 和单核细胞上的 LAIR-1 MFI 与单核细胞上的 CR-1 MFI 之间存在显着正相关( r  = 0.371; P  = 0.026）。受试者工作特征曲线显示，单核细胞上的 CR-1 MFI 具有最高的区分患者与对照组的能力，特异性为 86.1%，敏感性为 75%（P = 0.001）。总之，LAIR-1 和 CR-1 的白细胞表达改变与 PsV 相关。单核细胞上下调的 CR-1 MFI 是一种很有前途的 PsV 诊断生物标志物。