Serum Bovine Immunoglobulins Improve Inflammation and Gut Barrier Function in Persons with HIV and Enteropathy on Suppressive ART.

BackgroundSystemic inflammation persists in chronic HIV infection and is associated with increased rates of non-AIDS events such as cardiovascular and liver disease. Increased gut permeability and systemic exposure to microbial products are key drivers of this inflammation. Serum-derived bovine immunoglobulin/protein isolate (SBI) supports gut healing in other conditions such as inflammatory bowel disease.MethodsIn this randomized, double-blind study, participants receiving suppressive antiretroviral therapy (ART) with chronic diarrhea received placebo or SBI at 2.5 g BID or 5 g BID for 4 weeks, followed by a 20-week placebo-free extension phase with SBI at either 2.5 or 5 g BID. Intestinal fatty acid binding protein (I-FABP), zonulin, flagellin, lipopolysaccharide (LPS) and LPS-binding protein, and inflammatory markers were measured by ELISA or multiplex assays. Non-parametric tests were used for analysis.ResultsOne hundred three participants completed the study. By week 24 SBI significantly decreased circulating levels of I-FABP (-0.35 ng/μL, P=0.002) and zonulin (-4.90 ng/μL, P=0.003), suggesting improvement in gut damage, and interleukin-6 (IL-6) (-0.40 pg/μL, P=0.002), reflecting improvement in systemic inflammation. In participants with the lowest quartile of CD4+ T-cell counts at baseline (189-418 cells/μL), CD4+ T-cell counts increased significantly (26 cells/μL; P=0.002).ConclusionsOral SBI may decrease inflammation and warrants further exploration as a potential strategy to improve gut integrity and decrease systemic inflammation among persons receiving prolonged suppressive ART

The importance of high-throughput cell separation technologies for genomics/proteomics-based clinical diagnostics

Gene expression microarray analyses of mixtures of cells approximate a weighted average of the gene expression profiles (GEPs) of each cell type according to its relative abundance in the overall cell sample being analyzed. If the targeted subpopulation of cells is in the minority, or the expected perturbations are marginal, then such changes will be masked by the GEP of the normal/unaffected cells. We show that the GEP of a minor cell subpopulation is often lost when that cell subpopulation is of a frequency less than 30 percent. The GEP is almost always masked by the other cell subpopulations when that frequency drops to 10 percent or less. On the basis of these results one should always assume that the GEP of a given cell subpopulation is probably seriously affected by, the presence of significant numbers of other "contaminating" cell types. Several methodologies can be employed to enrich the target cells submitted for microarray analyses. These include magnetic sorting and laser capture microdissection. If a cell subpopulation of interest is small, very high-throughput cell separation technologies are needed to separate enough cells for conventional microarrays. However, high-throughput flow cytometry/cell sorting overcomes many restrictions of experimental enrichment conditions. This technology can also be used to sort smaller numbers of cells of specific cell subpopulations and subsequently amplify their mRNAs before microarray analyses. When purification techniques are applied to unfixed samples, the potential for changes in gene levels during the process of collection is an additional concern. Since RNA rapidly degrades, and specific mRNAs turn over in minutes or hours, the cell separation process must be very rapid. Hence, high-throughput cell separation (HTS) technologies are needed that can process the necessary number of cells expeditiously in order to avoid such uncontrolled changes in the target cells GEP. In cases where even the use of HTS yields only a small number of cells, the mRNAs (after reverse transcription to cDNA's) must be amplified to yield enough material for conventional microarray analyses. However, the problem of using "microamplification" PCR methods to expand the amount of cDNAs (from mRNAs) is that it is very difficult to amplify equally all of the mRNAs. Unequal amplification leads to a distorted gene expression profile on the microarray. Linear amplifications is difficult to achieve. Unfortunately, present-day gene-chips need to be about 100 times more sensitive than they are now to be able to do many biologically and biomedically meaningful experiments and clinical tests

The need of data harmonization to derive robust empirical relationships between soil conditions and vegetation.

Question: Is it possible to improve the general applicability and significance of empirical relationships between abiotic conditions and vegetation by harmonization of temporal data? Location: The Netherlands. Methods: Three datasets of vegetation, recorded after periods with different meteorological conditions, were used to analyze relationships between soil moisture regime (expressed by the mean spring groundwater level - MSLt calculated for different periods) and vegetation (expressed by the mean indicator value for moisture regime Fm). For each releve, measured groundwater levels were interpolated and extrapolated to daily values for the period 1970-2000 by means of an impulse-response model. Sigmoid regression lines between MSLt and Fm were determined for each of the three datasets and for the combined dataset. Results: A measurement period of three years resulted in significantly different relationships between Fm and MSLt for the three datasets (F-test,/? <0.05>. The three regression lines only coincided for the mean spring groundwater level computed over the period 1970-2000 (AfSLclimate) and thus provided a general applicable relationship. Precipitation surplus prior to vegetation recordings strongly affected the relationships. Conclusions: Harmonization of time series data (1) eliminates biased measurements, (2) results in generally applicable relationships between abiotic and vegetation characteristics and (3) increases the goodness of fit of these relationships. The presented harmonization procedure can be used to optimize many relationships between soil and vegetation characteristics. © IAVS; Opulus Press Uppsala

Naturally Rehearsing Passwords

We introduce quantitative usability and security models to guide the design of password management schemes --- systematic strategies to help users create and remember multiple passwords. In the same way that security proofs in cryptography are based on complexity-theoretic assumptions (e.g., hardness of factoring and discrete logarithm), we quantify usability by introducing usability assumptions. In particular, password management relies on assumptions about human memory, e.g., that a user who follows a particular rehearsal schedule will successfully maintain the corresponding memory. These assumptions are informed by research in cognitive science and validated through empirical studies. Given rehearsal requirements and a user's visitation schedule for each account, we use the total number of extra rehearsals that the user would have to do to remember all of his passwords as a measure of the usability of the password scheme. Our usability model leads us to a key observation: password reuse benefits users not only by reducing the number of passwords that the user has to memorize, but more importantly by increasing the natural rehearsal rate for each password. We also present a security model which accounts for the complexity of password management with multiple accounts and associated threats, including online, offline, and plaintext password leak attacks. Observing that current password management schemes are either insecure or unusable, we present Shared Cues--- a new scheme in which the underlying secret is strategically shared across accounts to ensure that most rehearsal requirements are satisfied naturally while simultaneously providing strong security. The construction uses the Chinese Remainder Theorem to achieve these competing goals

Oral serum-derived bovine immunoglobulin improves duodenal immune reconstitution and absorption function in patients with HIV enteropathy.

ObjectivesTo examine the impact of serum-derived bovine immunoglobulin, an oral medical food known to neutralize bacterial antigen and reduce intestinal inflammation, on restoration of mucosal immunity and gastrointestinal function in individuals with HIV enteropathy.DesignOpen-label trial with intensive 8-week phase of bovine serum immunoglobulin (SBI) 2.5 g twice daily with a 4-week washout period and an optional 9-month extension study.MethodsHIV enteropathy was defined as chronic gastrointestinal symptoms including frequent loose or watery stools despite no identifiable, reversible cause. Upper endoscopy for tissue immunofluorescent antibody assay and disaccharide gut permeability/absorption studies were performed before and after 8 weeks of SBI to test mucosal immunity and gastrointestinal function. Blood was collected for markers of microbial translocation, inflammation, and collagen kinetics. A validated gastrointestinal questionnaire assessed changes in symptoms.ResultsAll eight participants experienced profound improvement in symptoms with reduced bowel movements/day (P = 0.008) and improvements in stool consistency (P = 0.008). Gut permeability was normal before and after the intervention, but D-xylose absorption increased in seven of eight participants. Mucosal CD4 lymphocyte densities increased by a median of 139.5 cells/mm2 from 213 to 322 cells/mm2 (P = 0.016). Intestinal-fatty acid binding protein (I-FABP), a marker of enterocyte damage, initially rose in seven of eight participants after 8 weeks (P = 0.039), and then fell below baseline in four of five who continued receiving SBI (P = 0.12). Baseline serum I-FABP levels were negatively correlated with subsequent rise in mucosal CD4 lymphocyte densities (r = -0.74, P = 0.046).ConclusionSBI significantly increases intestinal mucosal CD4 lymphocyte counts, improves duodenal function, and showed evidence of promoting intestinal repair in the setting of HIV enteropathy

Low Sensitivity of T-Cell Based Detection of Tuberculosis among HIV Co-Infected Tanzanian In-Patients

Objective: To evaluate the performance of QuantiFERON-TB GOLD (QFTG) in a resource-poor setting among patients with and without HIV infection.Design: Cross-sectional study.Setting: Two hospitals in Northern Tanzania.Subjects: Eighty three adult male and female inpatients.Intervention: All patients were screened for HIV infection and underwent tuberculin skin test (TST) and QFTG.Results: Eighty-three subjects were enrolled, and 29 (35%) of 83 were HIV-infected. QFTG yielded indeterminate results in 12 (22%; 95%CI 12%-34%) of 54 HIV-uninfected and 13 (45%; 95%CI 26%-64%) of 29 HIV-infected subjects (p=0.0323). Among those with smear-positive pulmonary tuberculosis, TST was positive in 40 (100%; 95%CI 91%-100%) of 40 HIV-uninfected subjects compared with seven (54%; 95%CI 25%- 81%) of 13 HIV-infected subjects (p&lt;0.0001), and QFTG was positive in 28(70%; 95%CI 53%-83%) of 40 HIV-uninfected subjects compared with three (23%; 95%CI 5%-54%) of 13 HIV-infected subjects (p=0.0029). Among medical inpatients at risk for latent tuberculosis infection, TST was positive in seven (50%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p=0.0701) and QFTG was positive among two (14%) of 14 HIV-uninfected patients and three (19%) of 16 HIV-infected patients (p=0.7437).Conclusions: The presence of HIV co-infection was associated with a significant reduction in sensitivity of both the TST (p&lt;0.0001) and QFTG (p=0.0029) for the diagnosis of active M.tuberculosis infection. The high proportion of indeterminate QFTG and lack of sensitivity, particularly among HIV-infected patients, may limit its applicability in settings like Tanzania. Larger studies in resource-poor settings are required.

Effects of Combined CCR5/Integrase Inhibitors-Based Regimen on Mucosal Immunity in HIV-Infected Patients Naïve to Antiretroviral Therapy: A Pilot Randomized Trial

Whether initiation of antiretroviral therapy (ART) regimens aimed at achieving greater concentrations within gut associated lymphoid tissue (GALT) impacts the level of mucosal immune reconstitution, inflammatory markers and the viral reservoir remains unknown. We included 12 HIV- controls and 32 ART-naïve HIV patients who were randomized to efavirenz, maraviroc or maraviroc+raltegravir, each with fixed-dose tenofovir disoproxil fumarate/emtricitabine. Rectal and duodenal biopsies were obtained at baseline and at 9 months of ART. We performed a comprehensive assay of T-cell subsets by flow cytometry, T-cell density in intestinal biopsies, plasma and tissue concentrations of antiretroviral drugs by high-performance liquid chromatography/mass spectroscopy, and plasma interleukin-6 (IL-6), lipoteichoic acid (LTA), soluble CD14 (sCD14) and zonulin-1 each measured by ELISA. Total cell-associated HIV DNA was measured in PBMC and rectal and duodenal mononuclear cells. Twenty-six HIV-infected patients completed the follow-up. In the duodenum, the quadruple regimen resulted in greater CD8+ T-cell density decline, greater normalization of mucosal CCR5+CD4+ T-cells and increase of the naïve/memory CD8+ T-cell ratio, and a greater decline of sCD14 levels and duodenal HIV DNA levels (P = 0.004 and P = 0.067, respectively), with no changes in HIV RNA in plasma or tissue. Maraviroc showed the highest drug distribution to the gut tissue, and duodenal concentrations correlated well with other T-cell markers in duodenum, i.e., the CD4/CD8 ratio, %CD4+ and %CD8+ HLA-DR+CD38+ T-cells. Maraviroc use elicited greater activation of the mucosal naïve CD8+ T-cell subset, ameliorated the distribution of the CD8+ T-cell maturational subsets and induced higher improvement of zonulin-1 levels. These data suggest that combined CCR5 and integrase inhibitor based combination therapy in ART treatment naïve patients might more effectively reconstitute duodenal immunity, decrease inflammatory markers and impact on HIV persistence by cell-dependent mechanisms, and show unique effects of MVC in duodenal immunity driven by higher drug tissue penetration and possibly by class-dependent effects

Exogenous IFN-alpha Administration Reduces Influenza A Virus Replication in the Lower Respiratory Tract of Rhesus Macaques

To determine the role of innate immune responses in controlling influenza A virus replication, rhesus macaques (RM) were administered pegylated IFN-alpha prior to virus challenge. Systemic and mucosal pegylated IFN-alpha administration induced expression of the interferon-stimulated genes (ISG) MxA and OAS in the airways. RM treated with IFN-alpha 24 hours prior to influenza virus challenge had significantly lower peak vRNA levels in the trachea compared to untreated animals. In addition to blunting viral replication, IFN-alpha treatment minimized the weight loss and spike in body temperature after influenza infection of RM. These results confirm the importance of IFN-alpha induced innate immune responses in the rapid control of influenza A virus replication in primates

Severe Pediatric COVID-19 and Multisystem Inflammatory Syndrome in Children From Wild-type to Population Immunity:A Prospective Multicenter Cohort Study With Real-time Reporting

BACKGROUND: SARS-CoV-2 variant evolution and increasing immunity altered the impact of pediatric SARS-CoV-2 infection. Public health decision-making relies on accurate and timely reporting of clinical data. METHODS: This international hospital-based multicenter, prospective cohort study with real-time reporting was active from March 2020 to December 2022. We evaluated longitudinal incident rates and risk factors for disease severity. RESULTS: We included 564 hospitalized children with acute COVID-19 (n = 375) or multisystem inflammatory syndrome in children (n = 189) from the Netherlands, Curaçao and Surinam. In COVID-19, 134/375 patients (36%) needed supplemental oxygen therapy and 35 (9.3%) required intensive care treatment. Age above 12 years and preexisting pulmonary conditions were predictors for severe COVID-19. During omicron, hospitalized children had milder disease. During population immunity, the incidence rate of pediatric COVID-19 infection declined for older children but was stable for children below 1 year. The incidence rate of multisystem inflammatory syndrome in children was highest during the delta wave and has decreased rapidly since omicron emerged. Real-time reporting of our data impacted national pediatric SARS-CoV-2 vaccination- and booster-policies. CONCLUSIONS: Our data supports the notion that similar to adults, prior immunity protects against severe sequelae of SARS-CoV-2 infections in children. Real-time reporting of accurate and high-quality data is feasible and impacts clinical and public health decision-making. The reporting framework of our consortium is readily accessible for future SARS-CoV-2 waves and other emerging infections.</p