The contribution of innate immune cells, including natural killer (NK) and natural killer T (NKT) cells, in systemic lupus erythematosus (SLE) is still unclear. Herein, we examined the frequency of peripheral NK cells, CD56dim and CD56bright NK cells, and NKT cells in patients with juvenile SLE and their potential relations to SLE-related clinical and laboratory parameters. The study included 35 SLE children and 20 apparently healthy controls. After baseline clinical and lab work, SLE Disease Activity Index (SLEDAI-2K) and Pediatric Systemic Lupus International Collaborative Clinics/American College of Rheumatology (SLICC/ACR) Damage Index (Ped-SDI) scores were assessed. The frequency of peripheral NK cells, CD56dim and CD56bright NK cells, and NKT cells was examined using flow cytometry. SLE patients showed significantly lower frequency of NK cells and NKT cells and higher frequency of CD56bright NK cells compared to controls. Disease activity, urea, and creatinine correlated negatively with NK, but positively with CD56bright NK cells. NK and NKT cells exhibited inverse correlation with the renal biopsy activity index; however, CD56bright NK cells showed direct correlations with both activity and chronicity indices. Regarding Ped-SDI, renal, neuropsychiatry disorders, and growth failure correlated inversely with NK but directly with CD56bright NK cells. NKT cell inversely correlated with renal damage and delayed puberty. In conclusion, low frequency of NK and NKT and expansion of CD56bright NK cells are marked in juvenile SLE, particularly with activity. These changes have direct effect on renal impairment and growth failure, reflecting their potential influence on disease progression.

中文翻译：

---

幼年系统性红斑狼疮中的自然杀手和自然杀手T细胞：与疾病活动和进展的关系。

目前尚不清楚先天性免疫细胞在系统性红斑狼疮（SLE）中的作用，包括自然杀伤（NK）和自然杀伤T（NKT）细胞。本文中，我们检查了青少年SLE患者外周血NK细胞，CD56dim和CD56bright NK细胞以及NKT细胞的频率及其与SLE相关的临床和实验室参数的潜在关系。该研究包括35名SLE儿童和20名显然健康的对照。在完成基线临床和实验室工作后，评估了SLE疾病活动指数（SLEDAI-2K）和小儿系统性狼疮国际合作诊所/美国风湿病学会（SLICC / ACR）损伤指数（Ped-SDI）得分。使用流式细胞仪检查外周NK细胞，CD56dim和CD56bright NK细胞以及NKT细胞的频率。与对照组相比，SLE患者的NK细胞和NKT细胞频率明显降低，而CD56bright NK细胞频率更高。疾病活性，尿素和肌酐与NK呈负相关，但与CD56bright NK细胞呈正相关。NK和NKT细胞与肾活检活性指数呈负相关。然而，CD56bright NK细胞显示与活动性和慢性指数直接相关。关于Ped-SDI，肾脏，神经精神疾病和生长衰竭与NK成反比，但与CD56bright NK细胞成正比。NKT细胞与肾脏损害和青春期延迟呈负相关。总之，在青少年SLE中，NK和NKT的低频率和CD56bright NK细胞的扩增是明显的，特别是具有活性。这些变化直接影响肾功能损害和生长衰竭，