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Background & Objectives: Recurrent Aphthous Stomatitis (RAS) is one of the most common chronic ulcerative lesions of the oral mucosa and its development may be associated with oxidative stress. The aim of this study was to evaluate salivary Total Antioxidant Capacity (TAC) in patients with minor RAS. Materials & Methods: In this case-control study, 27 patients with minor RAS and 28 age- and sex-matched controls without RAS were enrolled. TAC was measured in unstimulated saliva for patients (during active lesion phase and after healing) and controls by immunologic assay. Data were analyzed by SPSS 18 using paired and unpaired t-tests (P Results: Salivary TAC levels of patients presented a significant increase from active lesion phase (0.26±0.16) to healing time (0.43±0.41); (P=0.034). There was no significant difference in the level of salivary TAC between patients during active lesion phase and controls (0.24±0.13); (P=0.641). Conclusion: Increasing level of salivary TAC may be involved in remission of RAS lesions, suggesting its evaluation in future studies.

Secretory immunoglobulin A (SIgA) in serum is possibly the best index of SIgA presence in mucosal secretions in digestive tract and the mirror of its immunologic barrier against many pathogenic aggressions. The measurement of salivary SigA alone may be affected by total salivary secretion and its final concentration in the gland lumen is probably not useful as an appropriate index of mucosal secretions in the digestive tract. The usefulness of the determination of SigA against various epitopes in serum from patients with various autoimmune disease has been demonstrated. The aetiology of many digestive related disorders could be triggered by an alteration of mucose SIgA barrier. The determination of Igs is important for different liver diseases and specifically the SIgA in autoimmune diseases such as rheumatoid arthritis. We developed an easy and efficient immunologic assay to quantify SIgA in serum samples.

Low folate concentrations are inversely associated with birth defects, including neural tube defects, congenital heart disease and oral clefts. Conversely, high folate concentrations may be associated with adverse outcomes, including increased risk of colorectal cancer among those with pre-existing neoplasms. The purpose of our study was to investigate the folate status of a nationally representative sample of Canadians, including a subset of women of childbearing age.We examined red blood cell folate concentrations among members of the general population aged 6-79 years (n = 5248) and separately among women of childbearing age (15-45 yr, n = 1162), as recorded by the Canadian Health Measures Survey and measured by immunologic assay. We assessed the data for significant differences by age, sex and socioeconomic status.Less than 1% of Canadians showed folate deficiency (red blood cell folate305 nmol/L) and 40% showed high folate concentrations (1360 nmol/L). Among women of childbearing age, 22% showed concentrations below those considered optimal for maximal neural tube defect-risk reduction (906 nmol/L). Significant differences by age and socio-economic status, but not sex, were evident in median red blood cell folate concentrations, although concentrations in all groups exceeded recommended levels. No differences by age or income were found among women of child-bearing age.Folate deficiency is virtually nonexistent in the Canadian population, although high folate concentrations are evident. Additional research is needed to better understand the determinants of red blood cell folate among women of childbearing age who have concentrations below levels that are maximally protective against neural tube defects. Ongoing monitoring of the folate status of Canadians and the relationship between red blood cell folate and health outcomes is warranted.

The prediction of efficacy of Neisseria meningitidis serogroup B (MenB) vaccines is currently hindered due to the lack of an appropriate correlate of protection. For outer membrane vesicle (OMV) vaccines, immunogenicity has primarily been determined by the serum bactericidal antibody (SBA) assay and OMV enzyme-linked immunosorbent assay (ELISA). However, the opsonophagocytic assay (OPA), surface labeling assay, whole blood assay (WBA), and salivary antibody ELISA have been developed although correlation with protection is presently undetermined. Therefore, the aim of the study was to investigate further the usefulness of, and relationships between, MenB immunologic assays. A phase II trial of the OMV vaccine, MenBvac, with proven efficacy was initiated to compare immunologic assays incorporating the vaccine and six heterologous strains. Correlations were achieved between the SBA assay, OMV ELISA, and OPA using human polymorphonuclear leukocytes and human complement but not between an OPA using HL60 phagocytic cells and baby rabbit complement. Correlations between the surface labeling assay, the SBA assay, and the OMV ELISA were promising, although target strain dependent. Correlations between the salivary antibody ELISA and other assays were poor. Correlations to the WBA were prevented since many samples had results greater than the range of the assay. The study confirmed the immunogenicity and benefit of a third dose of MenBvac against the homologous vaccine strain using a variety of immunologic assays. These results emphasize the need for standardized methodologies that would allow a more robust comparison of assays between laboratories and promote their further evaluation as correlates of protection against MenB disease.

29th Annual Jackson Hole, Wyoming, Update in Clinical Immunology, Microbiology and Infectious DiseasesSalt Lake city, UT, USA, 9–13 July 2012The 29th Annual Jackson Hole, Wyoming, Update in Clinical Immunology, Microbiology and Infectious Diseases was held from 9 to 13 July 2012. This postgraduate, continuing medical education course of the University of Utah’s Department of Pathology (UT, USA) is designed for laboratorians, clinical pathologists, pathologists, clinicians, clinical immunology and infectious disease specialists and medical technologists, as well as residents and fellows training in immunology, microbiology or infectious diseases.

We sought to determine if serum total iron-binding capacity (TIBC) is equivalent to serum transferrin (TRF) so that a low-cost colorimetric chemical assay for unsaturated iron-binding capacity (UIBC) could be substituted for a high-cost immunologic assay for TRF. Our study design included independent and blinded measurements of UIBC, serum iron, and TRF concentrations in human serum samples. Data from five independent correlation studies carried out at three different Quest Diagnostics laboratories were combined into one data set containing 570 paired results for TIBC and TRF. r2 was 0.941 when three outliers were eliminated from the 570-sample data set. Scatter about the regression line was fully accounted for by the CVs for the TIBC and TRF assays. When each test is measured precisely and without bias, the ratio of TIBC (μmol/L) to TRF (g/L) in SI units is close to the theoretically expected value of 25.0.

There have been significant advances in the development and application of novel therapeutic approaches and improved diagnostics for cancer in the past decade. Manipulation and/or assessment of cancer-specific immunity have been central to these advances. Murine models are a standard for the preclinical development of cancer immunotherapeutics. However, critical advances in our understanding of the role of the immune microenvironment and the assessment of cancer-specific immunity have not been fully applied to rodent models. Methods to preserve the function of immune cells after cryopreservation and standard approaches to quantitative immune assays have not been developed. Furthermore, a detailed evaluation of the immune tumor environment, which can impact a clinical response to different agents, is rarely undertaken as models are being contemplated. Rapid translation of immunoncology agents to the clinic will require standardization of immunologic assay methods and a more detailed immunologic characterization of common mouse models. Outlined here are the critical elements in assessing immunity in cancer mouse models and suggestions concerning the standardization of approaches when using these models for the study of immunoncology.

Background: Neonatal screening for steroid 21-hydroxylase (CYP21) deficiency is performed to identify congenital adrenal hyperplasia (CAH). The immunologic assay for 17α-hydroxyprogesterone (17-OHP) has a high rate of false positives. We assessed the potential for increasing the specificity for CAH by use of a second step involving analysis of the CYP21 gene. Methods: Between January 1999 and December 2003, a total of 810 000 newborns were screened. Of these, 7920 had to be retested because their 17-OHP values were above the cutoff of the assay. Sixty-one had positive 17-OHP values in their recall samples and were diagnosed as having CAH. We used a rapid assay for common mutations of the CYP21 gene to analyze these 61 samples. In a prospective study, 198 consecutive samples that had increased 17-OHP and 100 samples that had normal 17-OHP concentrations were genotyped. Results: Fifty-nine of 61 cases diagnosed as having CAH were confirmed genetically as CYP21 deficiencies. One patient had a 3β-hydroxysteroid dehydrogenase deficiency, and one patient carried no CYP21 mutations. The 198 increased 17-OHP results were designated as false positives after immunologic testing of recall samples. None of these samples exhibited the genetic pattern consistent with CYP21 deficiency. Conclusions: If samples with increased 17-OHP values were screened genetically, the number of retests would decrease by ∼90%, but the overall sensitivity of CAH screening would remain the same. Adding a second-tier genetic step would require a modest increase in costs, but is counterbalanced by fewer recalls, less clinical follow-up, and a reduction in unnecessary worry for families.

Diving mammals that descend to depths of 50-70 m or greater fully collapse the gas exchanging portions of their lungs and then reexpand these areas with ascent. To investigate whether these animals may have evolved a uniquely developed surfactant system to facilitate repetitive alveolar collapse and expansion, we have analyzed surfactant in bronchoalveolar lavage fluid (BAL) obtained from nine pinnipeds and from pigs and humans. In contrast to BAL from terrestrial mammals, BAL from pinnipeds has a higher concentration of phospholipid and relatively more fluidic phosphatidylcholine molecular species, perhaps to facilitate rapid spreading during alveolar reexpansion. Normalized concentrations of hydrophobic surfactant proteins B and C were not significantly different among pinnipeds and terrestrial mammals by immunologic assay, but separation of proteins by gel electrophoresis indicated a greater content of surfactant protein B in elephant seal surfactant than in human surfactant. Remarkably, surfactant from the deepest diving pinnipeds produced moderately elevated in vitro minimum surface tension measurements, a finding not explained by the presence of protein or neutral lipid inhibitors. Further study of the composition and function of pinniped surfactants may contribute to the design of optimized therapeutic surfactants.

The Collaboration for AIDS Vaccine Discovery/Comprehensive Antibody – Vaccine Immune Monitoring Consortium (CAVD/CA-VIMC) assisted an international network of laboratories in transferring a validated assay used to judge HIV-1 vaccine immunogenicity in compliance with Good Clinical Laboratory Practice (GCLP) with the goal of adding quality to the conduct of endpoint assays for Human Immunodeficiency Virus I (HIV-1) vaccine human clinical trials. Eight Regional Laboratories in the international setting (Regional Laboratories), many located in regions where the HIV-1 epidemic is most prominent, were selected to implement the standardized, GCLP-compliant Neutralizing Antibody Assay for HIV-1 in TZM-bl Cells (TZM-bl NAb Assay). Each laboratory was required to undergo initial training and implementation of the immunologic assay on-site and then perform partial assay re-validation, competency testing, and undergo formal external audits for GCLP compliance. Furthermore, using a newly established external proficiency testing program for the TZM-bl NAb Assay has allowed the Regional Laboratories to assess the comparability of assay results at their site with the results of neutralizing antibody assays performed around the world. As a result, several of the CAVD/CA-VIMC Regional Laboratories are now in the process of conducting or planning to conduct the GCLP-compliant TZM-bl NAb Assay as an indicator of vaccine immunogenicity for ongoing human clinical trials.

A B S T R A C T A heat-stable humoral substance (coagulopoietin-X) is present in rabbits partially depleted of Factor X, which is capable of raising Factor X levels when injected into recipient rabbits. Rabbits were partially depleted of Factor X by slow infusion of a globulin fraction of goat anti-rabbit Factor X antibody. This resulted in the reduction of Factor X to 40-50% of nonnal at 1 h and 60-70% of normal at 6 h. No effect was noted on levels of Factors II, V, or VII. Plasma from these animals, when injected into 10 recipients, specifically raised Factor X levels when measured by four different assays: one-stage assay with bovine VII- and X-deficient plasma and Russell's viper venom; one-stage assay with human X-deficient plasma and thromboplastin; chromogenic substrate assay with Russell's viper venom; and an immunologic assay (Laurell technique). No rise was noted in two control experiments in which normal plasma was injected into recipient rabbits from 2 rabbits injected with a globulin fraction of normal goat serum, nor in 12 rabbits injected with plasma from normal rabbits, nor in 5 rabbits injected with boiled plasma from normal rabbits. The rise in biologic activity of 120-150% of base line was significantly greater than the rise in immunologic activity of114-117% ofbase line (P < 0.05) on 3 different days, suggesting the production of a molecule with greater specific activity rather than increased protein synthesis.

A kindred with a history of multiple thromboses was studied for coagulant abnormalities. A deficiency of plasma antithrombin III was found in approximately half of the 13 family members by either coagulant or immunologic assay. No clear relationship between plasma antithrombin III deficiency and a history of thrombosis was present. Platelet antithrombin assays were studied in the same family. Ten of the 13 members were deficient. None of the three who was normal had a history of thrombosis. The plasma antithrombin III assays could be influenced by heparin or coumarin treatment. The same medications were without consistent effect on platelet antithrombin. On the basis of these findings, it is proposed that familial hypercoagulability in some cases may be due to a platelet antithrombin deficiency and that the plasma antithrombin III deficiency is a secondary effect.

The relation between functional antihemophilic factor (AHF) activity and AHF-like antigen was studied in the plasma of 25 known carriers of hemophilia. In 23 cases, this relationship was significantly different from that in normal women, at the 99% limit of confidence. In contrast, among families in which only one case of hemophilia had occurred, only five of nine mothers could be identified as carriers. This observation suggests that in some instances the hemophilia arose from a newly mutant gene. The data are consistent with the hypothesis that the proportion of antigen to AHF activity in carriers is determined by random activation or inactivation of the X chromosome.

In a prospective study, 1412 neonates were screened for congenital CMV infection by detection of viruria during the first week of life; 31 (2.2%) proved to be infected. Rheumatoid factor (RF) was present in the cord sera of 7 of 18 (38%) infected and 0 of 155 uninfected infants. Likewise IgM was elevated (≥20 mg%) in 7 of 18 (38%) infected patients (77% correlation with the presence of RF), but was also increased in 5 of 155 (3.2%) controls. IgM-CMV antibodies (FA) were detected in cord sera of 14 of 16 (88%) infected neonates and surprisingly in 14 of 59 (23%) controls. The false positive reactions in the IgM-FA were unrelated to the presence of RF, IgM elevation or poor specificity of the IgM conjugate. Because of the time required for conventional isolation of CMV and the poor sensitivity and specificity of the immunologic assays it seemed desirable to develop a more convenient diagnostic assay. A rapid viral isolation method based on the expression of specific 24 hrs. nuclear fluorescence was developed and assessed. In 19 of 20 (95%) urine samples containing CMV the diagnosis was correctly made only one day after receiving the samples. The number of positive nucleiper field correlated with the infectivity established by tube titration. This rapid assay has a specificity and sensitivity equivalent to the conventional CMV isolation method and matches the rapidity of the immunologic assays.