Dytrych Petra, Krol Petra, Kotrova Michaela, Kuzilkova Daniela, Hubacek Petr, Krol Ladislav, Katra Rami, Hrusak Ondrej, Kabelka Zdenek, Dolezalova Pavla, Kalina Tomas, Fronkova Eva
Department of ENT, Charles University, 2nd Faculty of Medicine, Charles University Prague and University Hospital Motol, Czech Republic.
Mol Immunol. 2015 May;65(1):139-47. doi: 10.1016/j.molimm.2015.01.004. Epub 2015 Feb 3.
PFAPA syndrome is a benign, recurrent inflammatory disease of childhood. Tonsillectomy is one of the therapeutic options with a yet unexplained biological mechanism. We tested whether specific lymphocyte subsets recruited from blood to human tonsils participate in PFAPA pathogenesis.
Paired tonsils/peripheral blood (PB) samples were investigated (a) from children with PFAPA that successfully resolved after tonsillectomy (n=10) (b) from children with obstructive sleep apnoea syndrome as controls (n=10). The lymphocyte profiles were analysed using 8-colour flow cytometry, immunoglobulin (IGH) and T-cell receptor (TCR) gene rearrangements via PCR and next generation sequencing; a TREC/KREC analysis was performed using qPCR.
The PFAPA tonsils in the asymptomatic phase had a lower percentage of B-lymphocytes than controls; T-lymphocyte counts were significantly higher in PB. The percentages of cytotoxic CD8pos T-lymphocytes were approximately 2-fold higher in PFAPA tonsils; the transitional B cells and naïve stages of both the CD4pos and CD8pos T-lymphocytes with a low expression of PD-1 molecule and high numbers of TREC were also increased. With the exception of elevated plasmablasts, no other differences were significant in PB. The expression levels of CXCL10, CXCL9 and CCL19 genes were significantly higher in PFAPA tonsils. The IGH/TCR pattern showed no clonal/oligoclonal expansion. DNA from the Epstein-Barr virus, Human Herpervirus-6 or adenovirus was detected in 7 of 10 PFAPA tonsils but also in 7 of 9 controls.
Our findings suggest that the uninhibited, polyclonal response of newly derived lymphocytes participate in the pathogenesis of PFAPA. Because most of the observed changes were restricted to tonsils and were not present in PB, they partly explain the therapeutic success of tonsillectomy in PFAPA syndrome.
PFAPA综合征是一种儿童期良性复发性炎症性疾病。扁桃体切除术是一种治疗选择，但其生物学机制尚不清楚。我们测试了从血液募集到人类扁桃体的特定淋巴细胞亚群是否参与PFAPA发病机制。
研究配对的扁桃体/外周血（PB）样本，（a）来自扁桃体切除术后成功缓解的PFAPA患儿（n = 10），（b）来自阻塞性睡眠呼吸暂停综合征患儿作为对照（n = 10）。使用8色流式细胞术分析淋巴细胞谱，通过PCR和下一代测序分析免疫球蛋白（IGH）和T细胞受体（TCR）基因重排；使用qPCR进行TREC/KREC分析。
无症状期的PFAPA扁桃体中B淋巴细胞百分比低于对照组；PB中的T淋巴细胞计数显著更高。PFAPA扁桃体中细胞毒性CD8阳性T淋巴细胞百分比约高2倍；CD4阳性和CD8阳性T淋巴细胞的过渡性B细胞和幼稚阶段，PD-1分子表达低且TREC数量多也增加。除浆母细胞升高外，PB中无其他显著差异。PFAPA扁桃体中CXCL10、CXCL9和CCL19基因的表达水平显著更高。IGH/TCR模式未显示克隆/寡克隆扩增。10个PFAPA扁桃体中有7个检测到爱泼斯坦-巴尔病毒、人类疱疹病毒-6或腺病毒的DNA，但9个对照中有7个也检测到。
我们的研究结果表明，新衍生淋巴细胞的不受抑制的多克隆反应参与PFAPA发病机制。因为观察到的大多数变化仅限于扁桃体，而不存在于PB中，它们部分解释了扁桃体切除术治疗PFAPA综合征的成功。
