Plasmacytoid monocytes migrate to inflamed lymph nodes and produce large amounts of type I interferon.

We have identified two cell subsets in human blood based on the lack of lineage markers (lin-) and the differential expression of immunoglobulin-like transcript receptor 1 (ILT1) and ILT3. One subset (lin-/ILT3+/ILT1+) is related to myeloid dendritic cells. The other subset (lin-/ILT3+/ILT1+) corresponds to 'plasmacytoid monocytes'. These cells are found in inflamed lymph nodes in and around the high endothelial venules. They express CD62L and CXCR3, and produce extremely large amounts of type I interferon after stimulation with influenza virus or CD40L. These results, with the distinct cell phenotype, indicate that plasmacytoid monocytes represent a specialized cell lineage that enters inflamed lymph nodes at high endothelial venules, where it produces type I interferon. Plasmacytoid monocytes may protect other cells from viral infections and promote survival of antigen-activated T cells.

An immunochemical procedure for determination of creatine kinase 3(1) (serum-specific) isoform in human serum evaluated.

Changes in the proportions of individual isoforms of creatine kinase (CK) in serum promptly reflect both myocardial infarction and coronary reperfusion. A new commercial kit has been introduced for measuring CK-3(1) isoform in serum (ISOFOR-MM, International Immunoassay Labs.). This is an immunochemical assay containing CK-3(1) specific monoclonal antibody, bound to magnetizable particles, used to immunoextract this isoform. The CK activity of the sample is measured before and after immunoextraction and the difference in the two values gives the measure of CK-3(1). Extraction of CK-3(1) was complete at less than or equal to 1200 U/L. Analysis of between-day imprecision gave CV between 2.9-7.9%. The method was not susceptible to interference by CK-3(2) and CK-3(3) isoforms, CK-2 isoenzyme, or mitochondrial CK. Reference interval for CK-3(1) (expressed as percent of total CK-3) was 42-69%. Correlation between percent CK-3(1) by isoform electrophoresis (x) and evaluated procedure (y) was y = 0.83x + 7.6, with r = 0.957 (n = 40). The ISOFOR-MM performed well enough in this evaluation to replace electrophoresis or isoelectric focusing for measurement of CK-3(1) isoform.

Diagnostic value of four assays for lipase determination in serum: a comparative reevaluation.

We assessed the diagnostic value of four commercially available methods for determining pancreatic lipase (LPS) in serum (the turbidimetric procedure from Boehringer, two enzymatic approaches from Kodak and Poli, and an immunochemical assay) in a population of 46 hospitalized patients with acute abdominal pain. In 31 cases (67.4%), the final diagnosis was acute pancreatitis. When evaluated by means of receiver-operating characteristic (ROC) curves, no significant differences were found among the procedures. Concerning clinical efficiency, all the assays had values equal to or greater than 90%. Using the calculation of the overlap index (OI) as a statistical approach to quantify the clinical utility of various LPS assays, the test having the greatest potential for differentiating between patients with and without acute pancreatitis was the turbidimetric assay (OI = 0.14).

Time course of changes in pancreatic enzymes, isoenzymes and, isoforms in serum after endoscopic retrograde cholangiopancreatography.

Kinetics of the catalytic activities of total amylase (AMY; EC 3.2.1.1), pancreatic (P)-AMY isoenzyme, P2 and P3 isoforms, and pancreatic lipase (LPS; EC 3.1.1.3), and of the mass concentration of LPS in serum were studied in 10 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) and showed a distinct pancreatic injury. The temporal characteristics of enzyme changes described were (a) the maximal rate (Ka) at which enzymes are released into blood, (b) the time lag from ERCP until maximum concentration value, (c) the peak value of each serum enzyme, and (d) the rate (Kd) at which each enzyme is cleared from serum. LPS activity and mass concentrations increased and decreased faster than AMY and isoamylases, and the time of the LPS peak tended to be earlier than that of the other enzymes, but not significantly. The average peak increase of LPS values was higher than that of total AMY, P-AMY, and P2 isoform (P less than 0.001). The P-AMY time-activity curve was a composite of curves attributable to its isoforms; the isoforms increased and peaked sequentially, with P3 returning to normal more slowly than did P2. LPS mass and activity concentrations showed excellent parallelism, with no important differences. At 50 h after ERCP, only LPS values still exceeded the upper reference limit, returning to normal 70 h after the examination.