miR-1291 Functions as a Potential Serum Biomarker for Bullous Pemphigoid

Background. Bullous pemphigoid (BP) is a common T helper 2- (Th2-) dominated autoimmune blistering skin disease with significant mortality. MicroRNAs (miRNAs), which are endogenous noncoding RNA molecules, have been reported to be potential biomarkers for some autoimmune diseases; however, to date, there exist no reports on serum expression profiles of miRNAs in BP patients. Methods. A RNA quantitative PCR- (qPCR-) based array was conducted on sera from 20 active BP patients and 20 healthy controls for screening of miRNAs. Significantly dysregulated miRNAs were validated with use of qPCR as performed on sera samples of 45 active BP patients and 60 healthy controls. Serum CCL17, anti-BP180, and anti-BP230 levels were measured with use of ELISA. Results. Relative baseline expression levels of serum miR-1291 were significantly upregulated in the 45 BP patients as compared with the 60 healthy controls (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mi>P</mml:mi><mml:mo>&lt;</mml:mo><mml:mn>0.001</mml:mn></mml:math>) and significantly decreased in the disease control stage (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>13</mml:mn></mml:math>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.006</mml:mn></mml:math>). In addition, these baseline miR-1291 levels showed a significant positive correlation with the baseline levels of serum CCL17 (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mi>P</mml:mi><mml:mo>&lt;</mml:mo><mml:mn>0.001</mml:mn></mml:math>) and anti-BP180 (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>38</mml:mn></mml:math>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M6"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.024</mml:mn></mml:math>). Like that observed for miR-1291, baseline levels of serum CCL17 were also significantly elevated in the 45 BP patients compared with the 60 healthy controls (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M7"><mml:mi>P</mml:mi><mml:mo>&lt;</mml:mo><mml:mn>0.001</mml:mn></mml:math>) and significantly decreased in the disease control stage (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M8"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>13</mml:mn></mml:math>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M9"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.002</mml:mn></mml:math>). However, for anti-BP180, baseline serum levels were significantly elevated in only 38 of the 45 BP patients and significantly decreased in the disease control stage (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M10"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>10</mml:mn></mml:math>, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M11"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.004</mml:mn></mml:math>). Conclusions . Relative expression levels of serum miR-1291 can reflect disease activity of BP. miR-1291 may function as an important new serum biomarker for BP.