Analytical Performance of a Novel Latex Turbidimetric Immunoassay, "Nanopia TARC", for TARC/CCL17 Measurement: A Retrospective Observational Study.

Thymus- and activation-regulated chemokine (TARC, also known as CCL17) is used as a biomarker for atopic dermatitis. The methods currently used for its measurement are complex, time-consuming, and require large machinery, warranting the need for a method that is simple, has a quick turnaround time, and requires less complex machinery. We evaluated the analytical performance of a novel latex turbidimetric immunoassay method, "Nanopia TARC", on 174 residual serum samples from patients with skin or allergic diseases. This evaluation included the assessment of the limit of blank/detection/quantification (LOB/D/Q), precision, accuracy, linearity, interference, and commutability between Nanopia TARC and "HISCL TARC", based on the chemiluminescent enzyme immunoassay (CLEIA) method. The LOB/D/Q values were 13, 57, and 141 pg/mL, respectively. The coefficient of variation of the repeatability was 0.9-3.8%, and that of the intermediate precision was 2.1-5.4%. The total error of the accuracy was 1.9-13.4%. The linearity was 141 and 19,804 pg/mL for TARC. The correlation coefficient between Nanopia TARC and HISCL TARC determined using the Passing-Bablok regression analysis was 0.999. Furthermore, the concordance of diagnostic criteria with AD was 92%. Nanopia TARC was confirmed to have the same analytical performance for TARC measurement as the existing CLEIA method.

Leucine-rich Alpha-2 Glycoprotein is a Serum Biomarker of Mucosal Healing in Ulcerative Colitis.

BACKGROUND AND AIMS: Although several noninvasive and easily accessible biomarkers for inflammatory bowel disease [IBD] are available, their sensitivity and specificity are not adequate to be used as single markers and do not overrule the need for endoscopic evaluation. We previously reported that serum leucine-rich alpha-2 glycoprotein [LRG] was a novel biomarker for rheumatoid arthritis and IBD. We herein investigated whether LRG could indicate endoscopic activity in patients with ulcerative colitis [UC]. METHODS: Serum LRG concentrations were determined by enzyme-linked immunosorbent assay [ELISA] in consecutive 129 patients with UC in two tertiary care hospitals, and associations of LRG with clinical and endoscopic activities were evaluated. Clinical activity index [CAI] < 6 was defined as clinical remission, and mucosal healing [MH] and complete mucosal healing were defined as Matts' endoscopic grades of 1 or 2 and grade of 1, respectively. RESULTS: Serum LRG levels were significantly increased and correlated with clinical and endoscopic activities in patients with UC. LRG levels were associated with both clinical and endoscopic activities even in patients with normal serum C-reactive protein [CRP] levels. Furthermore, LRG levels were significantly lower in patients with complete MH and deep remission. Serial measurements of LRG levels in a subset of patients demonstrated that LRG was significantly elevated during the endoscopically active stage compared with that during the MH stage. CONCLUSIONS: Serum LRG is a novel biomarker for detecting MH during disease course in patients with UC and a surrogate marker of endoscopic inflammation in patients with normal CRP levels.

[Measurement of serum undercarboxylated osteocalcin by ECLIA with the "Picolumi ucOC" kit].

We evaluated the effectiveness of the "Picolumi ucOC" kit for measuring the serum level of ucOC. When used with an autoanalyzer, the kit achieved highly sensitive and rapid measurement over a range of 0.39 to 50 ng/mL. Assessment of reproducibility testing showed good results, since the coefficient of variation was