Architect system

In the first trimester (median 13.2, 95% range 9.6, 7.6 weeks) and second trimester (median 20.4, 95% range 18.5, 23.5 weeks) maternal venous blood plasma samples were drawn [19 (link)–21 (link)]. Blood samples were centrifuged and thereafter stored at –80 °C. sFlt-1 and PlGF concentrations were analyzed using a prototype of a microparticle-enhanced immunoassay on the Architect System (Abbott Diagnostics B.V., Hoofddorp, the Netherlands). The between-run coefficients of variation for plasma sFlt-1 were 2.8% at 5.5 ng/mL and 2.3% at 34.0 ng/mL; and 4.7% at 24 pg/mL, and 3.8% at 113 pg/mL for plasma PlGF. The highest detected level was 150 ng/mL for sFlt-1 and 1500 pg/mL for PlGF [21 (link)]. The sFlt-1/PlGF ratio was calculated by dividing the sFlt-1 concentration by the PlGF concentration. Because these measurements were not normally distributed, we log-transformed them for further analyses. Maternal PlGF and sFlt-1 concentrations and sFlt-1/PlGF ratio were categorized as quintiles and analyzed across the full range after construction of standard deviation (SDS) scores.

All serum samples underwent testing for anti-nucleocapsid (N) protein IgG and anti-receptor-binding domain (RBD) IgG antibodies against the ancestral strain using the commercially available automated ARCHITECT system (Abbott Diagnostics, Abbott Park, IL, USA) employing a chemiluminescent microparticle immunoassay (CMIA). The determination of anti-N IgG utilized the SARS-CoV-2 IgG assay (Abbott Diagnostics, Abbott Park, IL, USA) in accordance with the manufacturer’s instructions, with seropositivity defined as ≥1.4. The assessment of anti-RBD IgG employed the SARS-CoV-2 IgG II Quant assay (Abbott Diagnostics, Abbott Park, IL, USA) with a positive threshold set at equal to or greater than 50 AU/mL in accordance with the manufacturer’s guidelines. Conversion to binding antibody units per milliliter (BAU/mL) was conducted by multiplying the numerical AU/mL value by a factor of 0.142. An anti-RBD IgG result equal to or greater than 7.1 BAU/mL was considered positive.

Tac whole blood concentrations were determined using a chemiluminscent microparticle immunoassay (CMIA, analysed on the Architect system, Abbott Diagnostics, IL, USA). The limit of detection was 1.5 ng/ml. The correlation coefficient of > 0.90 for the specimens between 2.0 and 30 ng/ml. The precision of ≤ 10% of the total coefficient variation (CV). Tac trough concentrations were collected prior to the morning doses. Frequency tacrolimus assays were performed 5 times in the first week, three times in the second week, and every week in the third and fourth weeks, as well as when there were clinical or biochemical parameter abnormalities.
According to the second European consensus report, the goal Tac C₀ in the first month was 7–12 ng/ml. The Rosendaal linear interpolation method was used to calculate the TTR [14 (link)]. The linear relationship between each Tac C₀ and the TTR was calculated by summing the time during which the value fell within this target ml during the first month.
In the group of patients developing AR, all the Tac levels and TTR prior to the AR diagnosis were obtained. In the patients with no AR, all the Tac levels and TTR during the first month were used in the analysis.

Evaluation of the patients involved a medical history, a physical examination, and laboratory tests (including the complete blood counts, biochemical tests). Anti-HCV was assessed using the ARCHITECT system (Abbott Diagnostics, Abbott Park, IL, USA). HCV-RNA loads were measured using the Roche Amplicor HCV test (the lower limit of detection was 15 IU/mL.) according to the manufacturer's instructions. HCV-RNA was detected at baseline (BL), week 4, week 12, week 24, week 36, EOT, and 24 weeks after treatment and the follow-up period. INNO-LiPA HCV II kit assay was used to determine the HCV genotype. Liver biopsy specimens were evaluated by two liver pathology specialists who were blinded to the etiology.

Blood samples were obtained from participants before the second dose of the BNT162b2 mRNA vaccination (median: 20 days [interquartile range (IQR): 20 to 21 days] after the first dose) and 2 weeks after the second dose (median: 13 days [IQR: 11 to 14 days] after the second dose). A SARS-CoV2 IgG assay was performed with chemiluminescent immunoanalysis of microparticles used for quantitative detection of IgG antibodies against the spike protein of the SARS CoV-2 virus (spike IgG) employing the Architect system (Abbott Diagnostics) with a cut-off <50 antibody units/mL (AU/mL) in both blood samples. To exclude the possibility of previous Covid-19 infection, we also measured IgG antibodies against the nucleocapsid protein of Covid-19 (Abbott Diagnostics) using the second blood sample. The negative cut-off value for anti-nucleocapsid protein IgG was < 1.4 AU/mL.

During the period covered by the study, three different test systems were used to screen for antibodies against T. gondii: from 1 January 1995 to 18 June 2006, the MCB service used slides coated with T. gondii for indirect immunofluorescence test (IIFT). From 19 June 2006 to 5 December 2010, the determinations were made with the automated Vidia Toxo IgG System from bioMérieux. Since 6 December 2010 Toxoplasma IgG has been determined automatically using the Architect System from Abbott Diagnostics. Toxoplasma IgM test to confirm seroconversion was determined with the following systems: from 1 January 1995 to 18 June 2006, the automated Vidas Toxo IgM System from bioMérieux; from 19 June 2006 to 5 December 2010, the automated Vidia IgM assay from bioMérieux; and since 6 December 2010, the automated Architect System IgM assay from Abbott Diagnostics.

The humoral immune response to SARS-CoV-2 was assessed by binding domain antibody and measured anti-RBD IgG by Quant assay using ARCHITECT system (Abbott Diagnostics, Chicago, IL, USA). The results were expressed in AU/mL units. The results with an Anti-RBD level of more than 40,000 AU/mL were diluted within a limited range as per the manufacturer’s protocol. Anti-Np antibody was quantified by Elecsys Anti-SAR-CoV-2 (Roche, Basel, Switzerland), which is a combined anti-SARS-CoV-2 nucleocapsid protein IgA/IgG/IgM detection immunoassay. A level above 10 AU/mL was determined to be positive.