Ciccocioppo Rachele, De Marchi Giulia, Zuliani Valeria, Adamo Annalisa, Amodio Antonio, Campagnola Pietro, Gabrieletto Enrico Maria, de Pretis Nicolò, Ugel Stefano, Delfino Pietro, Krampera Mauro, Frulloni Luca
Gastroenterology Unit - Pancreas Institute, Department of Medicine, A.O.U.I. Policlinico G.B. Rossi & University of Verona, Verona, Italy.
Hematology Unit, Department of Medicine, University of Verona, Verona, Italy.
Gastro Hep Adv. 2022 Apr 5;1(3):437-444. doi: 10.1016/j.gastha.2022.02.012. eCollection 2022.
BACKGROUND & AIMS: Type 1 autoimmune pancreatitis (AIP) is an IgG4-related disease whose diagnosis is challenging. The aim of this study was to investigate the diagnostic value of circulating total and IgG4 plasmablasts in differentiating this condition from the other main pancreatic diseases.
Patients with type 1 AIP (n = 19) were prospectively enrolled in a tertiary center together with patients suffering from type 2 or not otherwise specified (NOS) AIP (n = 10), pancreatic adenocarcinoma (n = 17), chronic pancreatitis (n = 20), and intraductal papillary mucinous neoplasia or chronic asymptomatic pancreatic hyperenzymemia (n = 21) as control groups. Flow cytometry was used to measure the total plasmablast and IgG4 plasmablast number by gating peripheral blood CD45CD19CD38CD20CD24CD27 and CD45CD19CD38CD20CD24CD27IgG4 cells, respectively. In patients with AIP, these cell populations were also evaluated after 1 month of therapy, after 2-4 months from the end of treatment, and after 1 year from the enrollment. The study was approved by the local ethics committee (protocol number: 59133, 30/11/2017).
Total plasmablast quantification was capable of discriminating type 1 AIP from all the other pancreatic disorders with a sensitivity of 47% and a specificity of 81%, according to a cutoff of 4500 cells/mL (AUC = 0.738), whereas IgG4 plasmablast count distinguished type 1 AIP from all the other pancreatic disorders with a sensitivity of 80% and a specificity of 97% when applying a cutoff of 210 IgG4 cells/mL (AUC = 0.879). The basal IgG4 plasmablast number was significantly higher ( = .0001) in type 1 AIP than in type 2/NOS AIP, decreased after steroid therapy, and increased at disease relapse.
IgG4 plasmablast count represents a potentially useful biomarker to differentiate type 1 from type 2/NOS AIP and from other pancreatic diseases.
1型自身免疫性胰腺炎（AIP）是一种IgG4相关疾病，其诊断具有挑战性。本研究的目的是探讨循环中总浆母细胞和IgG4浆母细胞在鉴别该疾病与其他主要胰腺疾病中的诊断价值。
前瞻性纳入一家三级中心的1型AIP患者（n = 19），并纳入2型或未另行指定（NOS）的AIP患者（n = 10）、胰腺腺癌患者（n = 17）、慢性胰腺炎患者（n = 20）以及导管内乳头状黏液性肿瘤或慢性无症状性胰腺酶血症患者（n = 21）作为对照组。采用流式细胞术分别通过门控外周血CD45CD19CD38CD20CD24CD27和CD45CD19CD38CD20CD24CD27IgG4细胞来测量总浆母细胞和IgG4浆母细胞数量。在AIP患者中，还在治疗1个月后、治疗结束后2 - 4个月以及入组后1年对这些细胞群体进行评估。该研究获得当地伦理委员会批准（方案编号：59133，2017年11月30日）。
根据4500个细胞/mL的临界值，总浆母细胞定量能够将1型AIP与所有其他胰腺疾病区分开来，敏感性为47%，特异性为81%（AUC = 0.738）；而当应用210个IgG4细胞/mL的临界值时，IgG4浆母细胞计数能将1型AIP与所有其他胰腺疾病区分开来，敏感性为80%，特异性为97%（AUC = 0.879）。1型AIP患者的基础IgG4浆母细胞数量显著高于2型/NOS AIP患者（P = 0.0001），在类固醇治疗后减少，在疾病复发时增加。
IgG4浆母细胞计数是区分1型与其他胰腺疾病以及2型/NOS AIP的一种潜在有用的生物标志物。
