Comparative analysis of human gut- and blood-derived mononuclear cells: contrasts in function and phenotype.

Introduction: Alterations in the gut immune system have been implicated in various diseases.The challenge of obtaining gut tissues from healthy individuals, commonly performed via surgical explants, has limited the number of studies describing the phenotype and function of gut-derived immune cells in health. Methods: Here, by means of recto-sigmoid colon biopsies obtained during routine care (colon cancer screening in healthy adults), the phenotype and function of immune cells present in the gut were described and compared to those found in blood. Results: The proportion of CD4+, CD8+, MAIT, γδ+ T, and NK cells phenotype, expression of integrins, and ability to produce cytokine in response to stimulation with PMA and ionomycin. T cells in the gut were found to predominantly have a memory phenotype as compared to T cells in blood where a naïve phenotype predominates. Recto-sigmoid mononuclear cells also had higher PD-1 and Ki67 expression. Furthermore, integrin expression and cytokine production varied by cell type and location in blood vs. gut. Discussion: These findings demonstrate the differences in functionality of these cells when compared to their blood counterparts and validate previous studies on phenotype within gut-derived immune cells in humans (where cells have been obtained through surgical means). This study suggests that recto-sigmoid biopsies collected during colonoscopy can be a reliable yet more accessible sampling method for follow up of alterations of gut derived immune cells in clinical settings.

A randomized control trial of high-dose micronutrient-antioxidant supplementation in healthy persons with untreated HIV infection.

BACKGROUND: Although micronutrient and antioxidant supplementation are widely used by persons with human immunodeficiency virus (HIV), a therapeutic role beyond recommended daily allowances (RDA) remains unproven. An oral high-dose micronutrient and antioxidant supplement (Treatment) was compared to an RDA supplement (Control) for time to progressive immunodeficiency or initiation of antiretroviral therapy (ART) in people living with HIV (PLWH). METHODS: This study was a randomized, double-blind, placebo-controlled multicenter clinical trial. PLWH were recruited from Canadian HIV Trials Network sites, and followed quarterly for two years. Eligible participants were asymptomatic, antiretroviral treatment (ART)-naïve, HIV-seropositive adults with a CD4 T lymphocyte count (CD4 count) between 375-750 cells/µL. Participants were randomly allocated 1:1 to receive Treatment or Control supplements. The primary outcome was a composite of time-to-first of confirmed CD4 count below 350 cells/µL, initiation of ART, AIDS-defining illness or death. Primary analysis was by intention-to-treat. Secondary outcomes included CD4 count trajectory from baseline to ART initiation or two years. A Data and Safety Monitoring Board reviewed the study for safety, recruitment and protocol adherence every six months. RESULTS: Of 171 enrolled participants: 66 (38.6%) experienced a primary outcome: 27 reached a CD4 count below 350 cells/µL, and 57 started ART. There was no significant difference in time-to-first outcome between groups (Hazard Ratio = 1.05; 95%CI: 0.65, 1.70), or in time to any component outcome. Using intent-to-treat censoring, mean annualized rates of CD4 count decline were -42.703 cells/µL and -79.763 cells/µL for Treatment and Control groups, with no statistical difference in the mean change between groups (-37.06 cells/µL/52 weeks, 95%CI: (-93.59, 19.47); p = 0.1993). Accrual was stopped at 171 of the 212 intended participants after an interim analysis for futility, although participant follow-up was completed. CONCLUSIONS: In ART-naïve PLWH, high-dose antioxidant, micronutrient supplementation compared to RDA supplementation had no significant effect on disease progression or ART initiation. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00798772.

Type of Pelvic Disease as a Risk Factor for Surgical Site Infectionin Women Undergoing Hysterectomy.

STUDY OBJECTIVE: To quantify the relationship between type of benign pelvic disease and risk of surgical site infection (SSI) after hysterectomy. DESIGN: Retrospective cohort study (Canadian Task Force classification II-2). SETTING: Hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP). PATIENTS: Women who underwent hysterectomy from 2006-2015 and recorded in NSQIP database. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: SSI risk was compared for type of benign pelvic disease, patient characteristics (i.e., age, race, and selected comorbidities) and process of care variables (i.e., admission status, type of hysterectomy, and operative time). SSI occurred in 2.48% of the 125,337 women who underwent hysterectomy. SSI was most frequent in patients with endometriosis and least frequent in those with genital prolapse (3.13% vs 1.39%; p <.0001). Following adjustment for potential confounders, the odds of SSI were higher in women undergoing hysterectomy for endometriosis (adjusted odds ratio [aOR], 1.79; 95% confidence interval [CI], 1.43- 2.25), uterine myomas (aOR, 1.28; 95% CI, 1.05-1.55), menstrual disorders (aOR, 1.46; 95% CI, 1.20-1.78), and pelvic pain (aOR, 1.75; 95% CI, 1.34-2.27) compared with women undergoing hysterectomy for genital prolapse. Other patient factors associated with SSI included age, body mass index, smoking, diabetes mellitus, chronic obstructive pulmonary disease, hypertension, and American Society of Anesthesiologists classification. Among process-of-care factors, inpatient status, route of hysterectomy, total vs subtotal hysterectomy, and operative time were also associated with SSI. CONCLUSION: In addition to various patient and process-of-care factors known to be associated with SSI, type of underlying pelvic disease is an independent risk factor for SSI in women undergoing hysterectomy for benign indications.

Improving the clinical relevance of a mouse pregnancy model of antiretroviral toxicity; a pharmacokinetic dosing-optimization study of current HIV antiretroviral regimens.

Animal models can be useful tools for the study of HIV antiretroviral (ARV) safety/toxicity in pregnancy and the mechanisms that underlie ARV-associated adverse events. The utility and translatability of animal model-based ARV safety/toxicity data is improved if ARVs are tested in clinically relevant concentrations. The objective of this work was to improve the clinical relevance of our mouse pregnancy model of ARV toxicity, by determining the doses of currently prescribed ARV regimens that would yield human therapeutic plasma concentrations. Pregnant mice were administered increasing doses of ARV combinations by oral gavage, followed by measurement of drug concentrations in the maternal plasma and amniotic fluid. Concentrations of ten different ARVs in maternal plasma and amniotic fluid samples of pregnant mice are presented, with dosing optimization to yield human pregnancy-relevant plasma drug concentrations. We have proposed optimal dosing for different regimen component drugs to achieve human therapeutic plasma levels, so that a clinically relevant standard dosing is established. A review of related ARV pharmacokinetic studies in (pregnant/non-pregnant) rodents and human pregnancy is also shown. We hope these data will inform and encourage the use of mouse pregnancy models in the study of ARV safety/toxicity.

Primary immune deficiency diseases as unrecognized causes of chronic respiratory disease.

BACKGROUND: More than half of all primary immune deficiency diseases (PIDD) affect antibody production and are well known as causes of recurrent sinusitis and lung infections. Chronic and recurrent infections of the upper and/or lower airways can contribute to inflammatory and obstructive processes in the lower airways which are initially reversible and considered "asthma", but can eventually cause irreversible remodeling and chronic obstructive pulmonary disease (COPD). Conversely, several lines of evidence suggest that many patients who present with a diagnosis of asthma have an increased incidence of infection, suggesting underlying host-defense defects. Asthma and respiratory infections in the first decades of life are recognized as risk factors for development of COPD, but when patients present with COPD as adults, underlying primary immune deficiency disease may be unrecognized. MAIN FINDINGS AND CONCLUSIONS: Detection of PIDD as a potentially treatable underlying contributor to recurrent/acute exacerbations and morbidity of COPD, and provision of immunoglobulin (Ig) G replacement therapy, when appropriate, may decrease the progression of COPD. Decreasing the severity and rate of exacerbations and admissions should improve the quality of life and longevity of an important subset of patients with COPD, while decreasing costs. Major steps toward achieving these goals include developing a high index of suspicion, more frequent use and appropriate interpretation of screening tests such as quantitative immunoglobulins and vaccine responses, and prompt institution of IgG replacement therapy when antibody deficiency has been diagnosed.

Taima (stop) TB: the impact of a multifaceted TB awareness and door-to-door campaign in residential areas of high risk for TB in Iqaluit, Nunavut.

BACKGROUND: The incidence rate of active tuberculosis (TB) disease in the Canadian Territory of Nunavut has shown a rising trend over the past 10 years. In 2010 it was 60 times greater than the national incidence rate. The objective of the Taima (translates to "stop" in Inuktitut) TB study was to implement and evaluate a public health campaign to enhance existing TB prevention efforts in Nunavut. METHODS: A TB awareness campaign followed by a door-to-door screening campaign was carried out in Iqaluit, Nunavut. The aim of the campaign was to raise awareness about TB, and to provide in-home screening and treatment for people living in residential areas at high risk for TB. Screening was based on geographic location rather than on individual risk factors. RESULTS: During the general awareness campaign an increase in the number of people who requested TB testing at the local public health clinic was observed. However, this increase was not sustained following cessation of the awareness campaign. Targeted TB screening in high risk residential areas in Iqaluit resulted in 224 individuals having TSTs read, and detection of 42 previously unidentified cases of latent TB, (overall yield of 18.8% or number needed to screen = 5.3). These cases of latent TB infection (LTBI) were extra cases that had not been picked up by traditional screening practices (34% relative increase within the community). This resulted in a 33% relative increase in the completion of LTBI treatment within the community. The program directly and indirectly identified 5/17 new cases of active TB disease in Iqaluit during the study period (29.5% of all incident cases). CONCLUSIONS: While contact tracing investigations remain a cornerstone of TB prevention, additional awareness, screening, and treatment programs like Taima TB may contribute to the successful control of TB in Aboriginal communities.

Use of signature-tagged mutagenesis to identify virulence determinants in Haemophilus ducreyi responsible for ulcer formation.

Elucidating the molecular mechanisms responsible for chancroid, a genital ulcer disease caused by Haemophilus ducreyi, has been hampered in part by the relative genetic intractability of the organism. A whole genome screen using signature-tagged mutagenesis in the temperature-dependent rabbit model (TDRM) of H. ducreyi infection uncovered 26 mutants with a presumptive attenuated phenotype. Insertions in two previously recognized virulence determinants, hgbA and lspA1, validated this genome scanning technique. Database interrogation allowed assignment of 24 mutants to several functional classes, including transport, metabolism, DNA repair, stress response and gene regulation. The attenuated virulence for a 3 strain with a mutation in hicB was confirmed by individual infection in the TDRM. The results from this preliminary study indicate that this high throughput strategy will further the understanding of the pathogenesis of H. ducreyi infection.

Design and methods of the MAINTAIN study: a randomized controlled clinical trial of micronutrient and antioxidant supplementation in untreated HIV infection.

Micronutrient deficiencies are common in HIV positive persons and are associated with a poorer prognosis, but the role of micronutrient supplementation in the medical management of HIV infection remains controversial, as some but not all studies show immunological and clinical benefit. Micronutrients supplementation could be a relatively low cost strategy to defer the initiation of expensive, potentially toxic and lifelong antiretroviral therapy. The MAINTAIN study is a Canadian multi-center randomized control double blind clinical trial to evaluate if micronutrient supplementation of HIV positive persons slows progression of immune deficiency and delays the need to start antiretroviral therapy and is safe, compared to standard multivitamins. Untreated asymptomatic HIV positive adults will receive a micronutrient and antioxidant preparation (n = 109) or an identical appearing recommended daily allowance multivitamin and mineral preparation (n = 109) for two years. Participants will be followed quarterly and monitored for time from baseline to CD4 T lymphocyte count <350 mm(3), or emergence of CDC-defined AIDS-defining illness, or the start of antiretroviral therapy. We will also compare safety and health related quality of life between groups. Primary analysis will compare the incidence of the composite primary outcome between study groups and will be by intention-to-treat. The study was originally expected to last three years, with accrual over one year and a minimum of two years follow up of the last enrolled participant. We discuss here the study design and methods, often used for evaluation of complementary and adjunctive treatments for health maintenance in HIV infection, which are common interventions.

Steady-State pharmacokinetics and tolerability of trans-resveratrol 2000 mg twice daily with food, quercetin and alcohol (ethanol) in healthy human subjects.

BACKGROUND AND OBJECTIVE: Trans-resveratrol is a polyphenol, which is found in red wine and has cancer chemo-preventive properties and disease-preventive properties. The pharmacokinetics of trans-resveratrol have been investigated in single-dose studies and in studies with relatively low dosages. The present study aimed to investigate the steady-state pharmacokinetics and tolerability of trans-resveratrol 2000 mg twice daily with food, quercetin and alcohol (ethanol). METHODS: This was a two-period, open-label, single-arm, within-subject control study in eight healthy subjects. The steady-state 12-hour pharmacokinetics of trans-resveratrol 2000 mg twice daily were studied with a standard breakfast, a high-fat breakfast, quercetin 500 mg twice daily and 5% alcohol 100 mL. Trans-resveratrol plasma concentrations were determined using liquid chromatography with tandem mass spectrometry. RESULTS: The mean (SD) area under the plasma concentration-time curve from 0 to 12 hours (AUC(12)) and maximum plasma concentration (C(max)) of trans-resveratrol were 3558 (2195) ng * h/mL and 1274 (790) ng/mL, respectively, after the standard breakfast. The high-fat breakfast significantly decreased the AUC(12) and C(max) by 45% and 46%, respectively, when compared with the standard breakfast. Quercetin 500 mg twice daily or 5% alcohol 100 mL did not influence trans-resveratrol pharmacokinetics. Diarrhoea was reported in six of the eight subjects. Significant but not clinically relevant changes from baseline were observed in serum potassium and total bilirubin levels. CONCLUSION: Trans-resveratrol 2000 mg twice daily resulted in adequate exposure and was well tolerated by healthy subjects, although diarrhoea was frequently observed. In order to maximize trans-resveratrol exposure, it should be taken with a standard breakfast and not with a high-fat meal. Furthermore, combined intake with quercetin or alcohol did not influence trans-resveratrol exposure.

The role of psychological and behavioral variables in quality of life and the experience of bodily pain among persons living with HIV.

With increased life expectancy of individuals living with HIV, quality of life (QOL) has become a focus of treatment. More research is needed to address pain-related QOL and modifiable variables, such as health behaviors, depressive symptoms, and coping styles, which could be included in treatment protocols to improve QOL among individuals with HIV. Objectives of this study were to (1) examine relationships among health behaviors, psychological variables, and QOL, particularly pain-specific QOL, (2) examine the relationships among coping, depressive symptoms, and QOL, and (3) compare QOL scores of individuals with HIV and population-based normative data. HIV positive men and women not currently on highly active antiretroviral therapy were recruited during regular visits to an HIV outpatient clinic. They completed the Medical Outcome Study Health Survey SF-36 scale, which includes a physical components scale, a mental components scale, and a bodily pain subscale. They also completed questionnaires assessing health behaviors, depressive symptoms, and coping styles. Participants (n=97) scored significantly lower on most aspects of QOL than age-matched Canadian and U.S. norms. Hierarchical multiple regressions revealed that physical activity and CD4 cell count were independently related to lower physical components scale scores; smoking and depressive symptoms were independently associated with lower mental components scale scores; and education, physical activity, and depressive symptoms were independently associated with lower pain-related QOL. Depressive symptoms mediated the relationship between coping styles and the mental components scale and pain-related QOL. Results suggest that targeting depressive symptoms, physical activity, and coping strategies as part of comprehensive treatment protocols could help improve pain-specific QOL and overall QOL among individuals with HIV.

Pneumocystis jiroveci pneumonia prophylaxis is not required with a CD4+ T-cell count < 200 cells/microl when viral replication is suppressed.

OBJECTIVE: To determine the safety of discontinuing Pneumocystis jiroveci pneumonia (PCP) prophylaxis, in patients on effective antiretroviral therapy with CD4+ T-cell counts that have plateaued at < 200 cells/microl. METHODS: We prospectively evaluated a cohort of HIV infected patients at a multidisciplinary HIV clinic with sustained HIV RNA levels < 50 copies/ml and CD4+ T-cell counts that have plateaued at < 200 cells/microl and who have discontinued PCP prophylaxis. RESULTS: Nineteen patients fulfilled the above criteria. Eleven had been taking daily trimethoprim-sulfamethoxazole, seven were receiving monthly aerosolized pentamidine, and one patient never received any prophylaxis. The median CD4+ T-cell count at the time of discontinuation and at the most recent determination were 120 (range, 34-184) and 138 (range, 6-201) cells/microl, respectively. To date, patients have been off PCP prophylaxis for a mean of 13.7 +/- 10.6 months and a median of 9.0 (range 3-39) months for a total of 261 patient-months. To date, no patient has developed PCP. This is significantly different from the risk of developing PCP with a CD4+ T-cell count of < 200 cells/microl in untreated HIV infection (rate difference 9.2%; 95% confidence interval, 5.7 to 12.8%; P < 0.05). CONCLUSION: With sustained suppression of viral replication, PCP prophylaxis may not be necessary, regardless of CD4+ T-cell count. This illustrates a degree of immune recovery that occurs with virologic suppression that is not reflected in absolute CD4+ T-cell count or percentage and suggests that guidelines for P. jiroveci pneumonia prophylaxis may need to be re-evaluated.

Comparison of the risks of atherosclerotic events versus death from other causes associated with antiretroviral use.

BACKGROUND: Studies considering the risk of atherosclerotic disease (AtD) associated with the use of HAART have reported inconsistent results. METHODS: Data on antiretroviral therapy (ART) use, risk factors for cardiovascular disease (CVD), AtD and death from other causes in 18 603 HIV-infected patients from two established cohorts were evaluated. The relative hazards of AtD and death from other causes were calculated using a proportional hazards competing risks framework. The impact of protease inhibitor (PI)-containing, non-nucleoside reverse transcriptase inhibitor (NNRTI)-containing or PI + NNRTI-containing regimens on these outcomes were compared to nucleoside reverse transcriptase inhibitor (NRTI)-only regimens or stopping therapy, adjusting for known CVD risk factors. RESULTS: In 77 480 person-years of follow-up (median duration 3.49 years) there were 318 AtD events including 92 myocardial infarctions and 2044 deaths. Older age, hypertension, diabetes mellitus, having smoked and HIV disease stage were significantly associated with increased risk of AtD. PI- and NNRTI-containing regimens significantly reduced the joint risk of either AtD or death from other causes compared to NRTI-only or stopping therapy [hazard ratio (HR) for PI-containing ART, 0.76, 95% confidence interval (CI), 0.73-0.78, P< 0.001; NNRTI-containing ART, 0.69, 95% CI, 0.65-0.74; P< 0.001). PI-containing ART was associated with a borderline significant increased risk of myocardial infarction (cause-specific HR for PI-containing ART 1.19, 95% CI, 1.01-1.40, P = 0.04) but not with increased risk of AtD compared to NRTI-only regimens or stopping therapy (cause-specific HR for PI-containing ART, 1.03, 95% CI, 0.95-1.13, P = 0.44). CONCLUSIONS: Overall benefits of PI- and NNRTI-based ART in reducing mortality significantly outweigh any risks of AtD in the "short-term" follow-up of this study. Traditional cardiac risk factors play an important role in determining AtD risk status.

Time-dependent interaction between lopinavir/ritonavir and fexofenadine.

This study investigated the effect of single-dose and steady-state lopinavir/ritonavir on the exposure to fexofenadine, as a measure of P-glycoprotein activity. Sixteen volunteers (8 women) received single-dose oral fexofenadine 120 mg alone, in combination with single-dose ritonavir 100 mg or lopinavir/ritonavir 400/100 mg (randomized 1:1, stratified by sex), and in combination with steady-state lopinavir/ritonavir 400/100 mg twice daily. Single-dose ritonavir and lopinavir/ritonavir increased the area under the fexofenadine plasma concentration-time curve from 0 to infinity (AUC(infinity)) by 2.2- and 4.0-fold, respectively (P < .02). Steady-state lopinavir/ritonavir increased the fexofenadine AUC(infinity) by 2.9-fold. No changes were observed in the fexofenadine elimination half-life (P > .12). The fexofenadine AUC(infinity) was increased by lopinavir/ritonavir, likely due to increased bioavailability secondary to P-glycoprotein inhibition. After repeated administration of lopinavir/ritonavir, the interaction was attenuated compared to the single-dose effect, although a net inhibitory effect was maintained. Time-dependent inhibition of P-glycoprotein by lopinavir/ritonavir should be considered when P-glycoprotein substrates are coadministered.

Use of intravenous immunoglobulin for treatment of neurologic conditions: a systematic review.

BACKGROUND: Given the increasing use of intravenous immunoglobulin (IVIG) for various neurologic conditions and uncertainty pertaining to its benefits and harms, a systematic review was conducted of randomized controlled trials (RCTs) evaluating IVIG for all neurologic indications for which there was at least one published trial. STUDY DESIGN AND METHODS: For this systematic review, a systematic search strategy was applied to MEDLINE (1966-June 2003) and the Cochrane Register of Controlled Trials (June 2003) to identify potentially eligible RCTs comparing IVIG to placebo or an active control. All dosage regimens were considered. Abstracts were excluded, and no restriction was placed on language of publication. Two investigators independently performed data extraction with a standardized form. Measures of effect were calculated for each trial independently, and studies were pooled based on clinical and methodologic judgment as to its appropriateness. Where pooling of trials was inappropriate, a qualitative discussion of findings is provided. RESULTS AND CONCLUSIONS: Thirty-seven trials representing 14 conditions were identified. IVIG is more effective than placebo for treatment of relapsing-remitting multiple sclerosis and idiopathic chronic inflammatory demyelinating polyneuropathy. There is also potential benefit for treatment of multifocal motor neuropathy, myasthenia gravis, dermatomyositis, stiff-person syndrome, and Lambert-Eaton myasthenic syndrome. There was insufficient evidence to determine whether IVIG therapy was more effective than plasma exchange for Guillain-Barré syndrome. There was also insufficient evidence regarding paraprotein-associated polyneuropathy. No evidence of benefit was observed for secondary progressive multiple sclerosis or inclusion body myositis.

Field evaluation of the Merlin immediate HIV-1 and -2 test for point-of-care detection of human immunodeficiency virus antibodies.

The Merlin Immediate HIV-1 and -2 Test (Merlin point-of-care [POC] test; Merlin Biomedical & Pharmaceutical) is a nitrocellulose membrane flow immunoassay performed at the POC with the use of blood obtained from a fingerprick. The results of this test were compared with those of enzyme immunoassay (EIA) performed on venous blood samples in the laboratory. Positive results of both tests were confirmed by a Western blot (WB). The study included 553 adults with known HIV (human immunodeficiency virus) seropositivity (all of whom had positive Merlin POC test results) and 2659 adults with unknown HIV serostatus (20 of whom had positive EIA/WB results; 19 of the 20 also had positive Merlin-POC test results). The sensitivity of the Merlin POC test was 95.0% for patients with an unknown HIV serostatus and 99.83% for those with a positive serostatus. For previously untested subjects, the test's specificity and positive predictive value were 100%, its negative predictive value was 99.96%, and its overall accuracy was 99.96%. The Merlin POC test is highly accurate for the detection of HIV antibodies.