Urinary IL-6 and IL-8 as predictive markers in bladder urothelial carcinoma: A pilot study

BACKGROUND

Cytokines are known to be a key a factor in numerous malignancies and to exert an important regulatory role in the tumor microenvironment. Interest has grown in understanding how cytokines modulate the tumor microenvironment and which cytokines may serve as markers of the tumor process; however, a complete picture of the cytokine landscape in bladder cancer remains unclear.

METHODS

Fresh urine specimens with sufficient volume were collected at random intervals. The urine concentrations of IL-8 (CXCL8), CCL18, and CXCL9 were determined using the standard commercially available enzyme immunoassay. The urine concentrations of IL-6 were determined using the high sensitivity enzyme immunoassay kit. Urinary cytokine concentrations were normalized with urinary creatinine concentrations.

RESULTS

Significantly elevated concentrations of IL-6 and IL-8 were detected in the urine from patients with urothelial carcinoma on follow-up compared to patients with benign follow-up. The presence of both IL-6 and IL-8 in the urine samples from the high grade urothelial carcinoma (HGUC) cohort revealed a clear discrimination when compared to samples from patients with benign follow-up. The presence of the combination of both IL-6 and IL-8 had a sensitivity of 90.0% and a specificity of 81.25%. Similar data were obtained when receiver operating characteristic analysis was performed on both IL-6 and IL-8 concentrations in the urine from patients with HGUC vs. the hematuria cohort.

CONCLUSIONS

The presence of IL-6 and IL-8 in urine specimens may have predictive value for urothelial carcinoma. However, a large longitudinal study is required to statistically eliminate confounding factors and support this theory.

Methodological approaches to optimize multiplex oral fluid SARS-CoV-2 IgG assay performance and correlation with serologic and neutralizing antibody responses

BACKGROUND

Oral fluid (hereafter, saliva) is a non-invasive and attractive alternative to blood for SARS-CoV-2 IgG testing; however, the heterogeneity of saliva as a matrix poses challenges for immunoassay performance.

OBJECTIVES

To optimize performance of a magnetic microparticle-based multiplex immunoassay (MIA) for SARS-CoV-2 IgG measurement in saliva, with consideration of: i) threshold setting and validation across different MIA bead batches; ii) sample qualification based on salivary total IgG concentration; iii) calibration to U.S. SARS-CoV-2 serological standard binding antibody units (BAU); and iv) correlations with blood-based SARS-CoV-2 serological and neutralizing antibody (nAb) assays.

METHODS

The salivary SARS-CoV-2 IgG MIA included 2 nucleocapsid (N), 3 receptor-binding domain (RBD), and 2 spike protein (S) antigens. Gingival crevicular fluid (GCF) swab saliva samples were collected before December 2019 (n = 555) and after molecular test-confirmed SARS-CoV-2 infection from 113 individuals (providing up to 5 repeated-measures; n = 398) and used to optimize and validate MIA performance (total n = 953). Combinations of IgG responses to N, RBD and S and total salivary IgG concentration (μg/mL) as a qualifier of nonreactive samples were optimized and validated, calibrated to the U.S. SARS-CoV-2 serological standard, and correlated with blood-based SARS-CoV-2 IgG ELISA and nAb assays.

RESULTS

The sum of signal to cutoff (S/Co) to all seven MIA SARS-CoV-2 antigens and disqualification of nonreactive saliva samples with ≤15 μg/mL total IgG led to correct classification of 62/62 positives (sensitivity [Se] = 100.0%; 95% confidence interval [CI] = 94.8%, 100.0%) and 108/109 negatives (specificity [Sp] = 99.1%; 95% CI = 97.3%, 100.0%) at 8-million beads coupling scale and 80/81 positives (Se = 98.8%; 95% CI = 93.3%, 100.0%] and 127/127 negatives (Sp = 100%; 95% CI = 97.1%, 100.0%) at 20-million beads coupling scale. Salivary SARS-CoV-2 IgG crossed the MIA cutoff of 0.1 BAU/mL on average 9 days post-COVID-19 symptom onset and peaked around day 30. Among n = 30 matched saliva and plasma samples, salivary SARS-CoV-2 MIA IgG levels correlated with corresponding-antigen plasma ELISA IgG (N: ρ = 0.76, RBD: ρ = 0.83, S: ρ = 0.82; all p < 0.001). Correlations of plasma SARS-CoV-2 nAb assay area under the curve (AUC) with salivary MIA IgG (N: ρ = 0.68, RBD: ρ = 0.78, S: ρ = 0.79; all p < 0.001) and with plasma ELISA IgG (N: ρ = 0.76, RBD: ρ = 0.79, S: ρ = 0.76; p < 0.001) were similar.

CONCLUSIONS

A salivary SARS-CoV-2 IgG MIA produced consistently high Se (> 98.8%) and Sp (> 99.1%) across two bead coupling scales and correlations with nAb responses that were similar to blood-based SARS-CoV-2 IgG ELISA data. This non-invasive salivary SARS-CoV-2 IgG MIA could increase engagement of vulnerable populations and improve broad understanding of humoral immunity (kinetics and gaps) within the evolving context of booster vaccination, viral variants and waning immunity.

The Pregnancy, Arsenic, and Immune Response (PAIR) Study in rural northern Bangladesh

BACKGROUND

Arsenic exposure and micronutrient deficiencies may alter immune reactivity to influenza vaccination in pregnant women, transplacental transfer of maternal antibodies to the foetus, and maternal and infant acute morbidity.

OBJECTIVES

The Pregnancy, Arsenic, and Immune Response (PAIR) Study was designed to assess whether arsenic exposure and micronutrient deficiencies alter maternal and newborn immunity and acute morbidity following maternal seasonal influenza vaccination during pregnancy.

POPULATION

The PAIR Study recruited pregnant women across a large rural study area in Gaibandha District, northern Bangladesh, 2018-2019.

DESIGN

Prospective, longitudinal pregnancy and birth cohort.

METHODS

We conducted home visits to enrol pregnant women in the late first or early second trimester (11-17 weeks of gestational age). Women received a quadrivalent seasonal inactivated influenza vaccine at enrolment. Follow-up included up to 13 visits between enrolment and 3 months postpartum. Arsenic was measured in drinking water and maternal urine. Micronutrient deficiencies were assessed using plasma biomarkers. Vaccine-specific antibody titres were measured in maternal and infant serum. Weekly telephone surveillance ascertained acute morbidity symptoms in women and infants.

PRELIMINARY RESULTS

We enrolled 784 pregnant women between October 2018 and March 2019. Of 784 women who enrolled, 736 (93.9%) delivered live births and 551 (70.3%) completed follow-up visits to 3 months postpartum. Arsenic was detected (≥0.02 μg/L) in 99.7% of water specimens collected from participants at enrolment. The medians (interquartile ranges) of water and urinary arsenic at enrolment were 5.1 (0.5, 25.1) μg/L and 33.1 (19.6, 56.5) μg/L, respectively. Water and urinary arsenic were strongly correlated (Spearman's ⍴ = 0.72) among women with water arsenic ≥ median but weakly correlated (⍴ = 0.17) among women with water arsenic < median.

CONCLUSIONS

The PAIR Study is well positioned to examine the effects of low-moderate arsenic exposure and micronutrient deficiencies on immune outcomes in women and infants.

REGISTRATION

NCT03930017.

Methodological approaches to optimize multiplex oral fluid SARS-CoV-2 IgG assay performance and correlation with serologic and neutralizing antibody responses

Background

Oral fluid (hereafter, saliva) is a non-invasive and attractive alternative to blood for SARS-CoV-2 IgG testing; however, the heterogeneity of saliva as a matrix poses challenges for immunoassay performance.

Objectives

To optimize performance of a magnetic microparticle-based multiplex immunoassay (MIA) for SARS-CoV-2 IgG measurement in saliva, with consideration of: i) threshold setting and validation across different MIA bead batches; ii) sample qualification based on salivary total IgG concentration; iii) calibration to U.S. SARS-CoV-2 serological standard binding antibody units (BAU); and iv) correlations with blood-based SARS-CoV-2 serological and neutralizing antibody (nAb) assays.

Methods

The salivary SARS-CoV-2 IgG MIA included 2 nucleocapsid (N), 3 receptor-binding domain (RBD), and 2 spike protein (S) antigens. Gingival crevicular fluid (GCF) swab saliva samples were collected before December, 2019 (n=555) and after molecular test-confirmed SARS-CoV-2 infection from 113 individuals (providing up to 5 repeated-measures; n=398) and used to optimize and validate MIA performance (total n=953). Combinations of IgG responses to N, RBD and S and total salivary IgG concentration (μg/mL) as a qualifier of nonreactive samples were optimized and validated, calibrated to the U.S. SARS-CoV-2 serological standard, and correlated with blood-based SARS-CoV-2 IgG ELISA and nAb assays.

Results

The sum of signal to cutoff (S/Co) to all seven MIA SARS-CoV-2 antigens and disqualification of nonreactive saliva samples with ≤15 μg/mL total IgG led to correct classification of 62/62 positives (sensitivity [Se]=100.0%; 95% confidence interval [CI]=94.8%, 100.0%) and 108/109 negatives (specificity [Sp]=99.1%; 95% CI=97.3%, 100.0%) at 8-million beads coupling scale and 80/81 positives (Se=98.8%; 95% CI=93.3%, 100.0%] and 127/127 negatives (Sp=100%; 95% CI=97.1%, 100.0%) at 20-million beads coupling scale. Salivary SARS-CoV-2 IgG crossed the MIA cutoff of 0.1 BAU/mL on average 9 days post-COVID-19 symptom onset and peaked around day 30. Among n=30 matched saliva and plasma samples, salivary SARS-CoV-2 MIA IgG levels correlated with corresponding-antigen plasma ELISA IgG (N: ρ=0.67, RBD: ρ=0.76, S: ρ=0.82; all p <0.0001). Correlations of plasma SARS-CoV-2 nAb assay area under the curve (AUC) with salivary MIA IgG (N: ρ=0.68, RBD: ρ=0.78, S: ρ=0.79; all p <0.0001) and with plasma ELISA IgG (N: ρ=0.76, RBD: ρ=0.79, S: ρ=0.76; p <0.0001) were similar.

Conclusions

A salivary SARS-CoV-2 IgG MIA produced consistently high Se (>98.8%) and Sp (>99.1%) across two bead coupling scales and correlations with nAb responses that were similar to blood-based SARS-CoV-2 IgG ELISA data. This non-invasive salivary SARS-CoV-2 IgG MIA could increase engagement of vulnerable populations and improve broad understanding of humoral immunity (kinetics and gaps) within the evolving context of booster vaccination, viral variants and waning immunity.

COVID-19 Serology at Population Scale: SARS-CoV-2-Specific Antibody Responses in Saliva

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of an ongoing pandemic that has infected over 36 million and killed over 1 million people. Informed implementation of government public health policies depends on accurate data on SARS-CoV-2 immunity at a population scale. We hypothesized that detection of SARS-CoV-2 salivary antibodies could serve as a noninvasive alternative to serological testing for monitoring of SARS-CoV-2 infection and seropositivity at a population scale. We developed a multiplex SARS-CoV-2 antibody immunoassay based on Luminex technology that comprised 12 CoV antigens, mostly derived from SARS-CoV-2 nucleocapsid (N) and spike (S). Saliva and sera collected from confirmed coronavirus disease 2019 (COVID-19) cases and from the pre-COVID-19 era were tested for IgG, IgA, and IgM to the antigen panel. Matched saliva and serum IgG responses (n = 28) were significantly correlated. The salivary anti-N IgG response resulted in the highest sensitivity (100%), exhibiting a positive response in 24/24 reverse transcription-PCR (RT-PCR)-confirmed COVID-19 cases sampled at >14 days post-symptom onset (DPSO), whereas the salivary anti-receptor binding domain (RBD) IgG response yielded 100% specificity. Temporal kinetics of IgG in saliva were consistent with those observed in blood and indicated that most individuals seroconvert at around 10 DPSO. Algorithms employing a combination of the IgG responses to N and S antigens result in high diagnostic accuracy (100%) by as early as 10 DPSO. These results support the use of saliva-based antibody testing as a noninvasive and scalable alternative to blood-based antibody testing.

COVID-19 serology at population scale: SARS-CoV-2-specific antibody responses in saliva

Non-invasive SARS-CoV-2 antibody testing is urgently needed to estimate the incidence and prevalence of SARS-CoV-2 infection at the general population level. Precise knowledge of population immunity could allow government bodies to make informed decisions about how and when to relax stay-at-home directives and to reopen the economy. We hypothesized that salivary antibodies to SARS-CoV-2 could serve as a non-invasive alternative to serological testing for widespread monitoring of SARS-CoV-2 infection throughout the population. We developed a multiplex SARS-CoV-2 antibody immunoassay based on Luminex technology and tested 167 saliva and 324 serum samples, including 134 and 118 negative saliva and serum samples, respectively, collected before the COVID-19 pandemic, and 33 saliva and 206 serum samples from participants with RT-PCR-confirmed SARS-CoV-2 infection. We evaluated the correlation of results obtained in saliva vs. serum and determined the sensitivity and specificity for each diagnostic media, stratified by antibody isotype, for detection of SARS-CoV-2 infection based on COVID-19 case designation for all specimens. Matched serum and saliva SARS-CoV-2 antigen-specific IgG responses were significantly correlated. Within the 10-plex SARS-CoV-2 panel, the salivary anti-nucleocapsid (N) protein IgG response resulted in the highest sensitivity for detecting prior SARS-CoV-2 infection (100% sensitivity at ≥10 days post-SARS-CoV-2 symptom onset). The salivary anti-receptor binding domain (RBD) IgG response resulted in 100% specificity. Among individuals with SARS-CoV-2 infection confirmed with RT-PCR, the temporal kinetics of IgG, IgA, and IgM in saliva were consistent with those observed in serum. SARS-CoV-2 appears to trigger a humoral immune response resulting in the almost simultaneous rise of IgG, IgM and IgA levels both in serum and in saliva, mirroring responses consistent with the stimulation of existing, cross-reactive B cells. SARS-CoV-2 antibody testing in saliva can play a critically important role in large-scale "sero"-surveillance to address key public health priorities and guide policy and decision-making for COVID-19.

Minimally Invasive Saliva Testing to Monitor Norovirus Infection in Community Settings

Background

Norovirus is a leading cause of acute gastroenteritis worldwide. Routine norovirus diagnosis requires stool collection. The goal of this study was to develop and validate a noninvasive method to diagnose norovirus to complement stool diagnostics and to facilitate studies on transmission.

Methods

A multiplex immunoassay to measure salivary immunoglobulin G (IgG) responses to 5 common norovirus genotypes (GI.1, GII.2, GII.4, GII.6, and GII.17) was developed. The assay was validated using acute and convalescent saliva samples collected from Peruvian children <5 years of age with polymerase chain reaction (PCR)–diagnosed norovirus infections (n = 175) and controls (n = 32). The assay sensitivity and specificity were calculated to determine infection status based on fold rise of salivary norovirus genotype-specific IgG using norovirus genotype from stool as reference.

Results

The salivary assay detected recent norovirus infections and correctly assigned the infecting genotype. Sensitivity was 71% and specificity was 96% across the evaluated genotypes compared to PCR-diagnosed norovirus infection.

Conclusions

This saliva-based assay will be a useful tool to monitor norovirus transmission in high-risk settings such as daycare centers or hospitals. Cross-reactivity is limited between the tested genotypes, which represent the most commonly circulating genotypes.

Evaluating congenital syphilis in a reverse sequence testing environment

OBJECTIVES

To examine the effect of maternal reverse-sequence (RS) syphilis screening on management of infants at risk for congenital syphilis (CS) using a standardized approach.

STUDY DESIGN

A retrospective study from 2011 to 2014 at an academic medical center using RS testing, involving chemiluminescent immunoassay (CIA), rapid plasma  reagin (RPR), and fluorescent treponemal antibody-absorption (FTA-ABS) assays for syphilis. Clinical management and outcomes of infants born to mothers with discordant (CIA+/RPR-/FTA+) serology were compared with national or internal guidelines.

RESULTS

Sixty-three infants were classified as discordant (n = 21), presumed false positive (CIA+/RPR-/FTA-; n = 16), or true positive (CIA+/RPR+; n = 26) based on maternal serology. Only 24% of cases in the discordant group underwent recommended full evaluation. None of the evaluated infants in the discordant group (n = 8) were diagnosed with CS.

CONCLUSIONS

Management of infants with discordant maternal RS serology remained reliant on clinical judgment. In our high-risk population, RS testing did not identify additional cases of CS.

Vitamin D Status Modifies the Response to Indoor Particulate Matter in Obese Urban Children with Asthma

BACKGROUND

Indoor fine particulate air pollution (PM_2.5) is linked to asthma morbidity; however, whether vitamin D status influences individual susceptibility to airborne exposures is unclear.

OBJECTIVE

We aimed to determine if vitamin D modifies the effects of indoor PM_2.5 on asthma symptoms in urban children.

METHODS

A total of 120 children aged 5 to 12 years with physician-diagnosed asthma were evaluated at baseline and every 3 months for 9 months. Indoor PM_2.5, serum 25-hydroxy vitamin D (25-OH D) levels, and asthma symptoms were simultaneously assessed at each time point. Adjusting for confounders, generalized estimating equations assessed the 3-way interaction effects of 25-OH D, obesity, and PM on asthma symptoms.

RESULTS

Children were of mean (standard deviation [SD]) age 9.7 (2.2) years, 36% were obese, and 95% self-reported black race. Mean (SD) PM_2.5 indoor exposure was 38.2 (42.9) μg/m³ and 25-OH D was 19.1 (7.5) ng/mL. Three-way interaction models demonstrated significantly greater PM_2.5-associated effects on daytime asthma symptoms only among obese children with low 25-OH D levels (odds ratio [OR]_PM2.5 = 1.26, P = .049 at vitamin D = 15.5 ng/mL, increasingly stronger PM effects at levels <15.5 ng/mL). In homes with increased PM_2.5, higher 25-OH D was associated with decreased symptom odds (eg, OR_{Vitamin D} = 0.87; P = .049 at PM_2.5 = 52.5 μg/m³, increasingly protective effects >52.5 μg/m³) among obese children.

CONCLUSIONS

Among obese urban children with asthma, low individual 25-OH D enhanced adverse respiratory effects associated with indoor PM_2.5. In high PM_2.5 environments, 25-OH D was protective against asthma symptoms. Optimizing vitamin D status in children may help reduce asthma morbidity driven by indoor air pollution.

Effect of baseline micronutrient and inflammation status on CD4 recovery post-cART initiation in the multinational PEARLS trial

BACKGROUND & AIMS

Nutritional deficiency and inflammation may impact CD4+ T cell recovery during combination antiretroviral therapy (cART), particularly in resource-limited settings where malnutrition is prevalent. The aim of this study was to investigate the relationship of micronutrient and inflammation biomarkers to CD4 recovery after cART initiation.

METHODS

We conducted a secondary analysis of a random sub-cohort sample (n = 270) from a multinational randomized trial of cART regimen efficacy among 1571 cART-naïve adults. We measured pre-cART serum levels of micronutrients (Vitamin A, B₆, B₁₂, D, total carotenoids, selenium, and iron) and inflammation (C-reactive protein, soluble CD14 (sCD14), IFNγ, TNFα, Interleukin-6, and C-X-C motif chemokine 10 (CXCL10/IP10), EndoCab (IgM)) biomarkers. Biomarker status (i.e. micronutrient deficiency vs. sufficiency and elevated vs. low inflammation) was defined using established cutoffs or quartiles. Mixed-effects linear regression models were used to determine the association of baseline (pre-cART) concentrations of individual biomarkers with CD4 recovery through 96 weeks post-cART initiation.

RESULTS

In models adjusting for time-dependent viral load and baseline CD4 count, age, sex, body mass index, country, treatment regimen, anemia and hypoalbuminemia status, pre-cART vitamin D deficiency was associated with lower CD4 recovery (-14.9 cells/mm³, 95% CI: -27.9, -1.8) compared to sufficiency. In contrast, baseline selenium deficiency (20.8 cells/mm³, 95% CI: 3.3, 38.3), vitamin A deficiency (35.9 cells/mm³, 95% CI: 17.6, 54.3) and high sCD14 (23.4 cells/mm³, 95% CI: 8.9, 37.8) were associated with higher CD4 recovery compared to sufficient/low inflammation status.

CONCLUSIONS

In summary, baseline vitamin D deficiency was associated with diminished CD4 recovery after cART initiation; impaired CD4 recovery may contribute to the poor clinical outcomes recently observed in individuals with vitamin D deficiency. Vitamin A, selenium and sCD14 were associated with CD4 recovery but future studies are needed to further explore these relationships.

Characterization of Primate Antibody Responses to Administered Murine Monoclonal Immunoglobulin

Murine monoclonal antibodies (MAb) are currently being assessed for their utility as tools in cancer management. Anti-murine immunoglobulin responses have been observed in many patients receiving monoclonal antibody treatment. In this study, we evaluated the response of primates to the administration of a monoclonal antibody. MAb B6.2, an antibody generated against a human breast tumor metastasis, was used as a prototype MAb. Baboons were inoculated with MAb B6.2 whole IgG, Fab', or F(ab')2 fragments. Blood samples were drawn at periodic intervals post-inoculation and the sera collected. Anti-murine immunoglobulin responses were detected using a solid-phase radioimmunoassay. The specificity of the antibody response was analyzed to determine if the response was directed against the species of origin of the MAb (species specificity), against the class of the MAb (isotype specificity), or against the hypervariable region of the MAb (idiotype specificity). We found that primates develop a humoral immune response against all three forms of the monoclonal antibody [IgG, Fab', and F(ab')2]. Furthermore, this antibody response demonstrated a high degree of specificity for the antigen binding site suggesting an idiotypic specificity. Using a competitive radioimmunoassay, the antibody response was found to interfere with antigen binding of MAb B6.2. These studies suggest that monoclonal antibody treatment can generate an anti-idiotypic response which may alter the efficacy of this mode of treatment.

Elevated serum levels of IL-6 and CXCL9 in autoimmune retinopathy (AIR) patients

Autoimmune retinopathy (AIR) is a rare immune-mediated retinopathy associated with circulating antiretinal antibodies (ARAs). Other prominent features of AIR include visual field deficits and photoreceptor dysfunction in the setting of progressive unexplained vision loss. The role of inflammation is poorly understood in AIR. Since cytokines play a central role in the initiation and development of inflammation, we evaluated the presence of proinflammatory cytokines and chemokines in AIR patient sera. We demonstrate that IL-6 and CXCL9 are both elevated in AIR patient sera. Moreover, the presence and concentration of these 2 molecules appear to correlate with AIR patient disease severity. This cytokine profile, IL-6 and CXCL9, has been described to participate in a variety of autoimmune and inflammatory diseases. Our study provides support for an activated inflammatory process in AIR and identifies possible mechanisms that can drive autoimmunity in this disease.

•

IL-6 and CXCL9 are both elevated in AIR patient sera.

•

The presence and concentration of IL-6 and CXCL9 correlate with AIR patient disease severity.

•

These cytokines may play a prominent role in the initiation and development of inflammation and autoimmunity.

•

The data provides evidence for activated inflammatory processes in AIR.

Development of an oral fluid immunoassay to assess past and recent hepatitis E virus (HEV) infection

BACKGROUND

Hepatitis E virus (HEV) infection causes significant morbidity and mortality worldwide, particularly among pregnant women. In clinical settings blood-based testing protocols are commonly used to diagnose HEV infection, but in community settings such invasive sampling can hinder study participation and limit discovery of the ecology and natural history of HEV infection. Oral fluid is a non-invasive biospecimen that can harbor pathogen-specific antibodies and has the potential to replace blood-based testing protocols.

OBJECTIVES

To develop an immunoassay to assess past and recent HEV infection that uses oral fluid instead of serum or plasma.

METHODS

The assay was validated using paired oral fluid and serum samples collected from 141 patients who presented either with (n=76) or without (n=65) symptoms of acute viral hepatitis at a clinical diagnostics center in Dhaka, Bangladesh. The sensitivity and specificity of the oral fluid-based immunoassay for HEV IgG (past HEV infection) and HEV IgA (recent HEV infection) antibodies was calculated in reference to Wantai's (Beijing Wantai) serum-based HEV enzyme-linked immunosorbent assay (ELISA) kits for IgG and IgM antibodies, respectively.

RESULTS

The sensitivity and specificity of the oral fluid-based immunoassay for HEV-IgG antibodies were 98.7% and 98.4%, respectively. The sensitivity and specificity of the oral fluid-based immunoassay for HEV IgA were 89.5% and 98.3%, respectively.

CONCLUSIONS

The high concordance of our non-invasive oral fluid-based immunoassays (HEV IgG and HEV IgA) with commercial high-performance serum HEV ELISA kits (IgG and IgM) means that population-based surveillance of past and recent HEV infection could be expanded to improve understanding of its ecology and natural history.

Pilot study of the effect of cholecalciferol supplementation on hepcidin in children with chronic kidney disease: Results of the D-fense Trial

BACKGROUND

Hepcidin is a key mediator of the anemia of chronic kidney disease (CKD). There is emerging evidence that 25-hydroxyvitamin D (25D) regulates hepcidin production.

METHODS

A randomized controlled trial of daily vitamin D supplementation for 12 weeks was performed with the aim to test the effects of 4000 versus 400 IU of cholecalciferol on serum hepcidin levels in children with non-dialysis CKD recruited at a tertiary care children's hospital. Hepcidin was quantified using a validated competitive enzyme-linked immunosorbent assay. 25D levels were measured using the chemiluminescence Liaison 25(OH)D assay system. Co-variables included hemoglobin, C-reactive protein, ferritin, and serum calcium and phosphorus for safety monitoring.

RESULTS

A total of 34 subjects were randomized to either the intervention or control group, of whom 26.5% were female and 23.5% were African American. The mean age of the study cohort was 10.9 [standard deviation (SD) 5.8] years, the mean baseline glomerular filtration rate was 60 (SD 17.6) ml/min/1.73 m², and mean baseline 25D level was 29.7 (SD 11.5) ng/ml. At baseline, 50% of subjects were 25D deficient. There were no significant differences in baseline characteristics between the intervention and control groups. Treatment with 4000 IU cholecalciferol was not associated with significant change in hepcidin level at 4 or 12 weeks, and multivariable generalized estimating equation regression demonstrated no significant difference in change in hepcidin over the treatment period in either arm. The median C-reactive protein level decreased significantly at 12 weeks in the intervention group.

CONCLUSIONS

These results do not suggest that daily nutritional vitamin D supplementation modifies serum hepcidin levels in children with CKD. Further study will be required to determine whether supplementation may be effective in children with more advanced CKD or those on dialysis.

Use of Pathogen-Specific Antibody Biomarkers to Estimate Waterborne Infections in Population-Based Settings

PURPOSE OF REVIEW

This review discusses the utility of pathogen-specific antibody biomarkers for improving estimates of the population burden of waterborne infections, assessing the fraction of infections that can be prevented by specific water treatments, and understanding transmission routes and the natural history and ecology of disease in different populations (including asymptomatic infection rates).

RECENT FINDINGS

We review recent literature on the application of pathogen-specific antibody response data to estimate incidence and prevalence of acute infections and their utility to assess the contributions of waterborne transmission pathways. Advantages and technical challenges associated with the use of serum versus minimally invasive salivary antibody biomarkers in cross-sectional and prospective surveys are discussed. We highlight recent advances and challenges and outline future directions for research, development, and application of antibody-based and other immunological biomarkers of waterborne infections.

Consensus on the Diagnosis and Management of Nonparaneoplastic Autoimmune Retinopathy Using a Modified Delphi Approach

PURPOSE

To develop diagnostic criteria for nonparaneoplastic autoimmune retinopathy (AIR) through expert panel consensus and to examine treatment patterns among clinical experts.

DESIGN

Modified Delphi process.

METHODS

A survey of uveitis specialists in the American Uveitis Society, a face-to-face meeting (AIR Workshop) held at the National Eye Institute, and 2 iterations of expert panel surveys were used in a modified Delphi process. The expert panel consisted of 17 experts, including uveitis specialists and researchers with expertise in antiretinal antibody detection. Supermajority consensus was used and defined as 75% of experts in agreement.

RESULTS

There was unanimous agreement among experts regarding the categorization of autoimmune retinopathies as nonparaneoplastic and paraneoplastic, including cancer-associated retinopathy and melanoma-associated retinopathy. Diagnostic criteria and tests essential to the diagnosis of nonparaneoplastic AIR and multiple supportive criteria reached consensus. For treatment, experts agreed that corticosteroids and conventional immunosuppressives should be used (prescribed) as first- or second-line treatments, though a consensus agreed that biologics and intravenous immunoglobulin were considered appropriate in the treatment of nonparaneoplastic AIR patients regardless of the stage of disease. Experts agreed that more evidence is needed to treat nonparaneoplastic AIR patients with long-term immunomodulatory therapy and that there is enough equipoise to justify randomized, placebo-controlled trials to determine if nonparaneoplastic AIR patients should be treated with long-term immunomodulatory therapy. Regarding antiretinal antibody detection, consensus agreed that a standardized assay system is needed to detect serum antiretinal antibodies. Consensus agreed that an ideal assay should have a 2-tier design and that Western blot and immunohistochemistry should be the methods used to identify antiretinal antibodies.

CONCLUSIONS

Consensus was achieved using a modified Delphi process to develop diagnostic criteria for nonparaneoplastic AIR. There is enough equipoise to justify randomized, placebo-controlled trials to determine whether patients with nonparaneoplastic AIR should be treated with long-term immunomodulatory therapy. Efforts to develop a standardized 2-tier assay system for the detection of antiretinal antibodies have been initiated as a result of this study.

Herpesvirus Infections and Risk of Frailty and Mortality in Older Women: Women's Health and Aging Studies

OBJECTIVES

To examine the relationship between herpesvirus infections and mortality and incident frailty risks in community-dwelling older women.

DESIGN

Nested prospective cohort study.

SETTING

Women's Health and Aging Studies I and II.

PARTICIPANTS

Community-dwelling older women aged 70 to 79 (n = 633).

MEASUREMENTS

Baseline serum antibody (immunoglobulin G) levels against four herpesviruses (herpes simplex virus types 1 (HSV-1) and 2 (HSV-2), varicella-zoster virus (VZV), 7 Epstein-Barr virus (EBV)), 3-year incident frailty rates, and 5-year mortality.

RESULTS

Women seropositive for HSV-1 and HSV-2, but not VZV and EBV, had higher risk of 3-year incident frailty (HSV-1: hazard ratio (HR) = 1.90, 95% confidence interval (CI) = 0.96-3.74; HSV-2: HR = 2.10, 95% CI = 1.05-4.37) and 5-year mortality (HR = 1.73, 95% CI = 0.93-3.20; HR = 1.80, 95% CI = 0.94-3.44, respectively) than seronegative women. Incremental increases in serum HSV-1 and HSV-2 antibody levels were associated with incrementally higher risks of incident frailty and mortality. After adjustment for potential confounders, only higher serum HSV-2 antibody level was independently predictive of higher risk of mortality in older women (for each unit increase in antibody index, HR = 1.47, 95% CI = 1.05-2.07).

CONCLUSION

HSV-1 and HSV-2 antibody levels are not independently associated with risk of incident frailty in older women. Only HSV-2 antibody level is independently predictive of 5-year mortality risk, with each incremental increase in the antibody level adding further risk.

Serum Interleukin-6 Levels and Pulmonary Function in Ataxia-Telangiectasia

OBJECTIVE

To evaluate the potential link between systemic inflammation and impaired lung function in people with ataxia-telangiectasia (A-T), we hypothesized that serum levels of interleukin (IL)-6, a proinflammatory cytokine, would correlate inversely with lung function in subjects with A-T.

STUDY DESIGN

Consecutive subjects with A-T were recruited from the Johns Hopkins Outpatient A-T Clinical Center. Serum levels of IL-6 and 8 were measured by enzyme-linked immunosorbent assay. Spirometry was performed in subjects ≥ 6 years of age on the same day that serum was obtained for measurements of cytokines.

RESULTS

Approximately 80% of subjects had elevated serum IL-6 levels (> 1.0 pg/mL). No association was found between elevated IL-6 and age. Elevated IL-8 levels were found in 23.6% of subjects, and all subjects with elevated IL-8 levels had elevated IL-6 levels. Subjects with elevated IL-6 levels (mean: 6.14 ± 7.47 pg/mL) had significantly lower mean percent forced vital capacity (FVC%, 50.5% ± 17.8%) compared with subjects with normal serum IL-6 levels (FVC% of 66.2 ± 16.1, P = .018). Greater IL-6 levels were associated with lower FVC% even after adjustment for receiving gamma globulin therapy (P = .024) and supplemental nutrition (P = .055).

CONCLUSIONS

An association was found between elevated serum IL-6 levels and lower lung function in subjects with A-T. In addition, subjects with both elevated IL-6 and IL-8 had the lowest mean lung function. These findings indicate that markers for systemic inflammation may be useful in identifying individuals with A-T at increased risk for lower lung function and may help in assessing response to therapy.

Low Vitamin-D Levels Combined with PKP3-SIGIRR-TMEM16J Host Variants Is Associated with Tuberculosis and Death in HIV-Infected and -Exposed Infants

Background

This study examined the associations of 25-hydroxyvitamin D and specific host genetic variants that affect vitamin D levels or its effects on immune function, with the risk of TB or mortality in children.

Methods

A case-cohort sample of 466 South African infants enrolled in P1041 trial (NCT00080119) underwent 25-hydroxyvitamin D testing by chemiluminescent immunoassay. Single nucleotide polymorphisms (SNPs) that alter the effect of vitamin D [e.g. vitamin D receptor (VDR)], vitamin D levels [e.g. vitamin D binding protein (VDBP)], or toll like receptor (TLR) expression (SIGIRR including adjacent genes PKP3 and TMEM16J) were identified by real-time PCR. Outcomes were time to TB, and to the composite of TB or death by 192 weeks of follow-up. Effect modification between vitamin D status and SNPs for outcomes was assessed.

Findings

Median age at 25-hydroxyvitamin D determination was 8 months; 11% were breastfed, 51% were HIV-infected and 26% had low 25-hydroxyvitamin D (<32ng/mL). By 192 weeks, 138 incident TB cases (43 definite/probable, and 95 possible) and 26 deaths occurred. Adjusting for HIV status and potential confounders, low 25-hydroxyvitamin D was associated with any TB (adjusted hazard ratio [aHR] 1.76, 95% CI 1.01–3.05; p = 0.046) and any TB or death (aHR 1.76, 95% CI 1.03–3.00; p = 0.038). Children with low 25-hydroxyvitamin D and TMEM 16J rs7111432-AA or PKP3 rs10902158-GG were at increased risk for probable/definite TB or death (aHR 8.12 and 4.83, p<0.05) and any TB or death (aHR 4.78 and 3.26, p<0.005) respectively; SNPs in VDBP, VDR, and vitamin D precursor or hydroxylation genes were not. There was significant interaction between low 25-hydroxyvitamin D and, TMEM 16J rs7111432-AA (p = 0.04) and PKP3 rs10902158-GG (p = 0.02) SNPs.

Conclusions

Two novel SNPs, thought to be associated with innate immunity, in combination with low vitamin D levels were identified as increasing a young child’s risk of developing TB disease or death. Identifying high-risk children and providing targeted interventions such as vitamin D supplementation may be beneficial.

Trial Registration

ClinicalTrials.gov NCT00080119

Inflammatory cytokines regulate secretion of VEGF and chemokines by human conjunctival fibroblasts: Role in dysfunctional tear syndrome

Ocular surface inflammation is one of the primary mechanisms associated with dysfunctional tear syndrome (DTS), also known as dry eye disease. DTS, more prevalent in older populations, causes ocular discomfort and visual disturbance due to dryness on the surface layer in the eye. We used human conjunctival fibroblast cultures (HCJVF) to investigate the effects of inflammatory cytokines IFN-γ, TNF-α and IL-1β (ITI) on the secretions of VEGF and chemokines. Our results demonstrate the elevated secretion of angiogenic VEGF molecules by ITI without affecting anti-angiogenic molecules, PEDF, endostatin, thrombospondin and sVEGF-R1. The secretion of interferon-γ inducible chemokines, CXCL9, -10, -11 by HCJVF were significantly enhanced by ITI. Our in vitro study supports previously reported observations of elevated VEGF and chemokines in tear fluids of DTS patients, reiterating the role of inflammatory reactions in DTS.

Inflammatory Cytokines Induce Expression of Chemokines by Human Retinal Cells: Role in Chemokine Receptor Mediated Age-related Macular Degeneration

Chemokine reeptor-3 (CCR-3) was shown to be associated with choroidal neovascularization (CNV) in age-related macular degeneration (AMD). AMD is a vision threatening retinal disease that affects the aging population world-wide. Retinal pigment epithelium and choroid in the posterior part of the retina are the key tissues targeted in the pathogenesis of CNV in AMD. We used human retinal pigment epithelial (HRPE) and choroidal fibroblast (HCHF) cells, prepared from aged adult human donor eyes, to evaluate the expression of major CCR-3 ligands, CCL-5, CCL -7, CCL-11,CCL-24 and CCL-26. Microarray analysis of gene expression in HRPE cells treated with inflammatory cytokine mix (ICM= IFN-γ+TNF-α+IL-1β) revealed 75 and 23-fold increase in CCL-5 and CCL-7 respectively, but not CCL-11, CCL-24 and CCL-26. Chemokine secretion studies of the production of CCL5 and CCL7 by HRPE corroborated with the gene expression analysis data. When the HRPE cells were treated with either individual cytokines or the ICM, both CCL-5 and CCL-7 were produced in a dose dependent manner. Similar to the gene expression data, the ICM did not enhance HRPE production of CCL-11, CCL-24 and CCL-26. CCL-11 and CCL-26 were increased with IL-4 treatment and this HRPE production was augmented in the presence of TNF-α and IL1β. When HCHF cells were treated with either individual cytokines or the ICM, both CCL-5 and CCL-7 were produced in a dose dependent fashion. IL-4 induced low levels of CCL-11 and CCL-26 in HCHF and this production was significantly enhanced by TNF-α. Under these conditions, neither HRPE nor HCHF were demonstrated to produce CCL-24. These data demonstrate that chronic inflammation triggers CCL-5 and CCL-7 release by HRPE and HCHF and the subsequent interactions with CCR3 may participate in pathologic processes in AMD.

Clinical laboratory immunology: an indispensable player in laboratory medicine

OBJECTIVES

Clinical laboratory immunology affects practically every aspect of medicine. Accordingly, appropriately trained, board-certified clinical laboratory immunologists are key contributors to the diagnosis and management of patients with various immune-mediated conditions. This review highlights the availability of postdoctoral level training programs for clinical laboratory immunology and identifies possible career tracks.

METHODS

Fundamental elements for doctoral level clinical laboratory immunologists are identified and the critical components of diagnostic immunology training as well as career opportunities in and out of academia are described.

RESULTS

Relative to other disciplines in laboratory medicine, little emphasis has been given to clinical laboratory immunology in medical, graduate, and postgraduate training. Formal postgraduate fellowship programs and board certification examinations are available, yet there remains a significant lack of awareness in the medical education community about the value and necessity of training in this field.

CONCLUSIONS

It is anticipated that sharing this knowledge will increase awareness of the discipline of clinical laboratory immunology at the postdoctoral level with implications for the practice of laboratory medicine.

Identification of α-fodrin as an autoantigen in experimental coronavirus retinopathy (ECOR)

The coronavirus, mouse hepatitis virus (MHV), JHM strain induces a biphasic disease in BALB/c mice that consists of an acute retinitis followed by progression to a chronic retinal degeneration with autoimmune reactivity. Retinal degeneration resistant CD-1 mice do not develop either the late phase or autoimmune reactivity. A mouse RPE/choroid DNA expression library was screened using sera from virus infected BALB/c mice. Two clones were identified, villin-2 protein and α-fodrin protein. α-Fodrin protein was used for further analysis and western blot reactivity was seen only in sera from virus infected BALB/c mice. CD4 T cells were shown to specifically react with MHV antigens and with α-fodrin protein. These studies clearly identified both antibody and CD4 T cell reactivities to α-fodrin in sera from virus infected, retinal degenerative susceptible BALB/c mice.

25-Hydroxyvitamin D insufficiency and deficiency is associated with HIV disease progression and virological failure post-antiretroviral therapy initiation in diverse multinational settings

BACKGROUND

Low 25-hydroxyvitamin D (25(OH)D) has been associated with increased HIV mortality, but prospective studies assessing treatment outcomes after combination antiretroviral therapy (cART) initiation in resource-limited settings are lacking.

METHODS

A case-cohort study (N = 411) was nested within a randomized cART trial of 1571 cART-naive adults in 8 resource-limited settings and the United States. The primary outcome (WHO stage 3/4 disease or death within 96 weeks of cART initiation) was met by 192 cases, and 152 and 29 cases met secondary outcomes of virologic and immunologic failure. We studied prevalence and risk factors for baseline low 25(OH)D (<32 ng/mL) and examined associated outcomes using proportional hazard models.

RESULTS

Low 25(OH)D prevalence was 49% and ranged from 27% in Brazil to 78% in Thailand. Low 25(OH)D was associated with high body mass index (BMI), winter/spring season, country-race group, and lower viral load. Baseline low 25(OH)D was associated with increased risk of human immunodeficiency virus (HIV) progression and death (adjusted hazard ratio (aHR) 2.13; 95% confidence interval [CI], 1.09-4.18) and virologic failure (aHR 2.42; 95% CI, 1.33-4.41).

CONCLUSIONS

Low 25(OH)D is common in diverse HIV-infected populations and is an independent risk factor for clinical and virologic failure. Studies examining the potential benefit of vitamin D supplementation among HIV patients initiating cART are warranted.

Change in vitamin d levels occurs early after antiretroviral therapy initiation and depends on treatment regimen in resource-limited settings

Study Background

Vitamin D has wide-ranging effects on the immune system, and studies suggest that low serum vitamin D levels are associated with worse clinical outcomes in HIV. Recent studies have identified an interaction between antiretrovirals used to treat HIV and reduced serum vitamin D levels, but these studies have been done in North American and European populations.

Methods

Using a prospective cohort study design nested in a multinational clinical trial, we examined the effect of three combination antiretroviral (cART) regimens on serum vitamin D levels in 270 cART-naïve, HIV-infected adults in nine diverse countries, (Brazil, Haiti, Peru, Thailand, India, Malawi, South Africa, Zimbabwe and the United States). We evaluated the change between baseline serum vitamin D levels and vitamin D levels 24 and 48 weeks after cART initiation.

Results

Serum vitamin D levels decreased significantly from baseline to 24 weeks among those randomized to efavirenz/lamivudine/zidovudine (mean change: −7.94 [95% Confidence Interval (CI) −10.42, −5.54] ng/ml) and efavirenz/emtricitabine/tenofovir-DF (mean change: −6.66 [95% CI −9.40, −3.92] ng/ml) when compared to those randomized to atazanavir/emtricitabine/didanosine-EC (mean change: −2.29 [95% CI –4.83, 0.25] ng/ml). Vitamin D levels did not change significantly between week 24 and 48. Other factors that significantly affected serum vitamin D change included country (p<0.001), season (p<0.001) and baseline vitamin D level (p<0.001).

Conclusion

Efavirenz-containing cART regimens adversely affected vitamin D levels in patients from economically, geographically and racially diverse resource-limited settings. This effect was most pronounced early after cART initiation. Research is needed to define the role of Vitamin D supplementation in HIV care.

Evaluation of monoclonal and oligoclonal gammopathies in a pediatric population in a major urban center

OBJECTIVES

A growing body of literature has documented monoclonal proteins in children. Little is known about their associated diagnoses.

METHODS

We retrospectively evaluated all patients (aged 0-21 years) with abnormal findings on serum immunofixation electrophoresis (SIFE) from 2005 to 2011. We also documented the monoclonal immunoglobulin classes and light chain types involved and then correlated these data with the clinical diagnoses.

RESULTS

A total of 695 SIFE tests were performed on this patient population. Of these, 95 SIFE tests (14%) identified a gammopathy (from 83 different patients), and of these, 74 (11%) demonstrated only a monoclonal gammopathy (from 63 different patients). The most common associated diagnosis in the study interval was ataxia-telangiectasia (22%). No patient in the study population was diagnosed with multiple myeloma or Waldenström macroglobulinemia.

CONCLUSIONS

The significance and presence of a monoclonal or oligoclonal gammopathy in pediatric and young adult populations is distinct from that seen in adults.

Resveratrol Suppresses Expression of VEGF by Human Retinal Pigment Epithelial Cells: Potential Nutraceutical for Age-related Macular Degeneration

Age-related macular degeneration (AMD) is a sight threating retinal eye disease that affects millions of aging individuals world-wide. Choroid-retinal pigment epithelium (RPE)-neuroretina axis in the posterior compartment of the eye is the primary site of AMD pathology. There are compelling evidence to indicate association of vascular endothelial growth factors (VEGF) to AMD. Here, we report the inhibitory actions of resveratrol (RSV) on inflammatory cytokine, TGF-β and hypoxia induced VEGF secretion by human retinal pigment epithelial cells (HRPE). HRPE cultures prepared from aged human donor eyes were used for the studies in this report. HRPE secreted both VEGF-A and VEGF-C in small quantities constitutively. Stimulation with a mixture of inflammatory cytokines (IFN-γ, TNF-α, IL-1β), significantly increased the secretion of both VEGF-A and VEGF-C. RSV, in a dose dependent (10-50 uM) manner, suppressed VEGF-A and VEGF-C secretion induced by inflammatory cytokines significantly. RT-PCR analysis indicated that effects of RSV on VEGF secretion were possibly due to decreased mRNA levels. TGF-β and cobalt chloride (hypoxia mimic) also upregulated HRPE cell production of VEGF-A, and this was inhibited by RSV. In contrast, RSV had no effect on anti-angiogenic molecules, endostatin and pigment epithelial derived factor secretion. Studies using an in vitro scratch assay revealed that wound closure was also inhibited by RSV. These results demonstrate that RSV can suppress VEGF secretion induced by inflammatory cytokines, TGF-β and hypoxia. Under pathological conditions, over expression of VEGF is known to worsen AMD. Therefore, RSV may be useful as nutraceutical in controlling pathological choroidal neovascularization processes in AMD.

Vitamin D deficiency is associated with development of subclinical coronary artery disease in HIV-infected African American cocaine users with low Framingham-defined cardiovascular risk

Chronic cocaine use may lead to premature atherosclerosis, but the prevalence of and risk factors for coronary artery disease (CAD) in asymptomatic cocaine users have not been reported. The objective of this study was to examine whether vitamin D deficiency is associated with the development of CAD in human immunodeficiency virus (HIV)-infected African American cocaine users with low CAD risk.

METHODS

In this prospective follow-up study, we investigated 169 HIV-infected African American cocaine users with low Framingham risk at baseline. The main outcome measures were incidence of subclinical CAD and development of subclinical CAD.

RESULTS

Fifty of the 169 African Americans had evidence of subclinical disease on the initial cardiac computed tomography. A second cardiac computed tomography was performed on the 119 African Americans without disease on the first scan. The total sum of person-years of follow-up was 289.6. Subclinical CAD was detected in 11 of these, yielding an overall incidence of 3.80/100 person-years (95% confidence interval 1.90-6.80). Among the factors investigated, only vitamin D deficiency was independently associated with development of subclinical CAD. The study did not find significant associations between CD4 count, HIV viral load, or antiretroviral treatment use and the incidence of subclinical CAD. This study appears to suggest that there is a threshold level of vitamin D (10 ng/mL) above which the effect of vitamin D on subclinical CAD is diminished.

CONCLUSION

The incidence of subclinical CAD in HIV-infected African American cocaine users with low CAD risk is high, especially in those with vitamin D deficiency. Well designed randomized clinical trials are warranted to confirm the role of vitamin D deficiency in the development of CAD in HIV-infected African American cocaine users with low CAD risk.

Vitamin D deficiency is associated with the development of subclinical coronary artery disease in African Americans with HIV infection: a preliminary study

BACKGROUND

Premature coronary artery disease (CAD) is a major concern in human immunodeficiency virus (HIV)-infected African Americans. The objectives of the study were to estimate the incidence of subclinical CAD, defined by the presence of coronary plaque and/or calcification on cardiac computed tomography (CT), and to identify the associated risk factors in this vulnerable population.

SUBJECTS AND METHODS

Between August 2003 and September 2010, 188 HIV-infected African Americans without known, or symptoms of, CAD underwent cardiac CT. The subset without demonstrable disease underwent a second cardiac CT approximately 2 years later. The incidence of disease over that period and the effects of antiretroviral treatment and other known and hypothesized risk factors were investigated.

RESULTS

Sixty-nine of these 188 African Americans had evidence of subclinical disease on the initial cardiac CT, confirming prior high prevalence reports. A second cardiac CT was performed on 119 African Americans without disease approximately 2 years later. The total person-years of follow-up was 284.4. Subclinical CAD was detected in 14 of these, yielding an overall incidence of 4.92/100 person-years (95% confidence interval, 2.69-8.26). Among the factors investigated, only male sex and vitamin D deficiency were independently associated with the development of subclinical CAD. The study did not find significant associations between CD4 count, HIV viral load, antiretroviral treatment use, or cocaine use and the incidence of subclinical CAD.

CONCLUSIONS

The incidence of subclinical CAD in African Americans with HIV infection is provocatively high. Larger studies are warranted to confirm the role of vitamin D deficiency in the development of CAD in HIV-infected African Americans.

Vitamin D deficiency is associated with coronary artery calcification in cardiovascularly asymptomatic African Americans with HIV infection

OBJECTIVE

Patients with HIV infection are at increased risk for coronary artery disease (CAD), and growing evidence suggests a possible link between vitamin D deficiency and clinical/subclinical CAD. However, the relationship between vitamin D deficiency and coronary artery calcification (CAC), a sensitive marker for subclinical CAD, in those with HIV infection is not well investigated.

METHODS

CAC was quantified using a Siemens Cardiac 64 scanner, and vitamin D levels and the presence of traditional and novel risk factors for CAD were obtained in 846 HIV-infected African American (AA) participants aged 25 years or older in Baltimore, MD, USA without symptoms or clinical evidence of CAD.

RESULTS

The prevalence of vitamin D deficiency (25-hydroxy vitamin D <10 ng/mL) was 18.7%. CAC was present in 238 (28.1%) of the 846 participants. Logistic regression analysis revealed that the following factors were independently associated with CAC: age (adjusted odds ratio [OR]: 1.11; 95% confidence interval [CI]: 1.08-1.14); male sex (adjusted OR: 1.71; 95% CI: 1.18-2.49); family history of CAD (adjusted OR: 1.53; 95% CI: 1.05-2.23); total cholesterol (adjusted OR: 1.006; 95% CI: 1.002-1.010); high-density lipoprotein cholesterol (adjusted OR: 0.989; 95% CI: 0.979-0.999); years of cocaine use (adjusted OR: 1.02; 95% CI: 1.001-1.04); duration of exposure to protease inhibitors (adjusted OR: 1.004; 95% CI: 1.001-1.007); and vitamin D deficiency (adjusted OR: 1.98; 95% CI: 1.31-3.00).

CONCLUSION

Both vitamin D deficiency and CAC are prevalent in AAs with HIV infection. In order to reduce the risk for CAD in HIV-infected AAs, vitamin D levels should be closely monitored. These data also suggest that clinical trials should be conducted to examine whether vitamin D supplementations reduce the risk of CAD in this AA population.

Vitamin D deficiency is associated with silent coronary artery disease in cardiovascularly asymptomatic African Americans with HIV infection

BACKGROUND

Growing evidence suggests that vitamin D deficiency Is associated with clinical coronary artery disease (CAD). The relationship between vitamin D deficiency and subclinical CAD in HIV-infected individuals is not well-characterized.

METHODS

Computed tomographic (CT) coronary angiography was performed using contrast-enhanced 64-slice multidetector CT imaging, and vitamin D levels and the presence of traditional and novel risk factor for CAD were obtained in 674 HIV-infected African American (AA) participants aged 25-54 years in Baltimore, MD, without symptoms/clinical evidence of CAD.

RESULTS

The prevalence of vitamin D deficiency (25-hydroxy vitamin D <10 ng/mL) was 20.0% (95% confidence interval [CI], 16.9-23.1). Significant (≥50%) coronary stenosis was present in 64 (9.5%) of 674 participants. Multiple logistic regression analysis revealed that male gender (adjusted odds ratio [OR], 2.19; 95% CI, 1.17-4.10), diastolic BP ≥85 mmHg (adjusted OR: 1.94, 95% CI: 1.02 -3.68), low-density lipoprotein cholesterol ≥100 mg/dL (adjusted OR, 1.95; 95% CI, 1.13-3.36), cocaine use for ≥15 years (adjusted OR, 1.77; 95% CI, 1.01-3.10), use of antiretroviral therapies for ≥6 months (adjusted OR, 2.26; 95% CI, 1.17-4.36), year of enrollment after 2005 (adjusted ORs for 2006-2007, 2008-2009, and 2010 were 0.32 [95% CI, 0.13-0.76], 0.26 [95% CI, 0.12-0.56], and 0.32 (95% CI, 0.15-0.65], respectively), and vitamin D deficiency (adjusted OR, 2.28; 95% CI, 1.23-4.21) were independently associated with significant coronary stenosis.

CONCLUSIONS

Both vitamin D deficiency and silent CAD are prevalent in HIV-infected AAs. In addition to management of traditional CAD risk factors and substance abuse, vitamin D deficiency should be evaluated in HIV-infected AAs. These data support the conduct of a prospective trial of vitamin D in this high-risk patient population.

Regulation of VEGF expression in human retinal cells by cytokines: implications for the role of inflammation in age-related macular degeneration

Chronic inflammation is implicated in the pathogenesis of age-related macular degeneration (AMD). Choroidal neovascularization (CNV) observed in exudative form of AMD results in vision loss. Human retinal pigment epithelial cell (HRPE) layer and choroidal tissue are the primary pathological sites in AMD. Pathological and therapeutic evidences have strongly indicated the vascular endothelial growth factor (VEGF) molecules as critical components in CNV pathogenesis. In these studies, we used human primary HRPE and choroidal fibroblast cells (HCHF) prepared from adult donor eyes. The effects of inflammatory cytokine (IFN-γ+ TNF-α+IL-1β) mix (ICM) on global gene expression profiles in HRPE cells, revealed 10- and 9-fold increase in VEGF-A and VEGF-C expression, respectively. The microarray results were validated by quantitative RT-PCR and secretion of VEGFs proteins. IL-1β is the most potent in inducing VEGFs secretion followed by IFN-γ and TNF-α, and the secretion was more effective in the presence of 2 and 3 cytokines. NF-κB and JAK-STAT pathway, but not HIF-1α, Sp-1, Sp-3, and STAT-3, transcription factors were upregulated and translocated to nucleus by ICM treatment. The mRNA levels of VEGF-A and VEGF-C and secretion of these proteins were also significantly enhanced by ICM in HCHF cells. The secretion of other angiogenic molecules, PEDF, SDF-1α, endostatin, and angiopoietins was not affected by ICM. Our results show that the inflammatory cytokines enhance secretion of VEGF-A and VEGF-C by HRPE and HCHF cells. These studies indicate that VEGFs secreted by these cells initiate and promote pathological choroidal and retinal noevascularization processes in AMD.

γ/IgG ratio: role in distinguishing monoclonal spikes from fibrinogen

Serum protein electrophoresis (SPEP) is a standard screening method for detecting monoclonal gammopathies. Presence of fibrinogen, however, can mimic a true monoclonal spike and interfere with accurate monoclonal protein identification. We describe a novel approach for distinguishing fibrinogen spikes from true monoclonal spikes. We classified 600 individual patient samples into four groups: group 1, 58 samples with a fibrinogen spike; group 2, 127 samples with a spike due to a monoclonal gammopathy; group 3, 181 samples with previously established monoclonal gammopathies but resolved posttreatment; and group 4, 234 control samples without monoclonal gammopathies. The value of using a γ region fraction/IgG ratio in distinguishing fibrinogen from true monoclonal spikes was assessed. The γ/IgG ratio in the fibrinogen group is significantly (P<0.0001) higher than this ratio in the other three groups. A γ/IgG ratio cut-off value of 1.13 discriminates true monoclonal gammopathies from fibrinogen. Moreover, exclusion of elevated IgA or IgM cases improves the ratio's predictive power. The probability cut-off is 0.756, corresponding to a γ/IgG ratio of 1 (93% sensitivity, 91% specificity). Using the γ/IgG ratio improves the screening power of SPEP and offers a simple and reliable diagnostic tool for distinguishing fibrinogen spikes from true monoclonal spikes.

Vitamin D deficiency is associated with significant coronary stenoses in asymptomatic African American chronic cocaine users

BACKGROUND

Chronic cocaine use may lead to premature atherosclerosis, however, the prevalence of and risk factors for coronary artery disease in asymptomatic cocaine users have not been reported.

METHODS

Between August 2007 and June 2010, 385 African American chronic cocaine users aged 25 to 54 years were consecutively enrolled in a study to investigate the prevalence of CT angiographically-defined significant (≥ 50%) coronary stenosis and related risk factors. Sociodemographic, drug-use behavior, medical history and medication data were obtained by interview and confirmed by medical chart review. Clinical examinations were performed as well as extensive laboratory tests including those for fasting lipid profiles, HIV, high sensitivity C-reactive protein, and vitamin D. Contrast-enhanced coronary CT angiography was performed.

RESULTS

Significant coronary stenosis was detected in 52 of 385 participants (13.5%). The prevalences were 12% and 30% in those with low risk and with middle-high risk Framingham score, respectively. In those with low risk scores, the prevalences of significant stenosis were 10% and 18% in those without and with vitamin D deficiency, defined as serum 25-(OH) vitamin D< 10 ng/mL (p=0.08). Multiple logistic regression analysis revealed that vitamin D deficiency (adjusted OR=2.18, 95% CI: 1.07-4.43) is independently associated with the presence of significant coronary stenosis after controlling for traditional risk factors.

CONCLUSIONS

The study indicates that the prevalence of significant coronary stenoses is high in asymptomatic young and middle-aged African American chronic cocaine users. These findings emphasize the importance of aggressive reduction of risk factors, including vitamin D deficiency in this population.

Cytomegalovirus infection and the risk of mortality and frailty in older women: a prospective observational cohort study

Cytomegalovirus (CMV), a prevalent pathogen, causes severe disease in immunocompromised humans. However, present understanding is limited regarding the long-term clinical effect of persistent CMV infection in immunocompetent adults. The authors conducted a prospective observational cohort study (1992-2002) of 635 community-dwelling women in Baltimore, Maryland, aged 70-79 years in the Women's Health and Aging Studies to examine the effect of CMV infection on the risk of frailty, a common geriatric syndrome, and mortality in older women. The effect of baseline serum CMV antibody (immunoglobulin G) concentration on the risk of 3-year incident frailty, defined by using a 5-component measure, and 5-year mortality was examined with Cox proportional hazards models. Compared with those who were CMV seronegative, women in the highest quartile of CMV antibody concentration had a greater incidence of frailty (hazard ratio = 3.46, 95% confidence interval: 1.45, 8.27) and mortality (hazard ratio = 3.81, 95% confidence interval: 1.64, 8.83). After adjustment for potential confounders, CMV antibody concentration in the highest quartile independently increased the risk of 5-year mortality (hazard ratio = 2.79, 95% confidence interval: 1.22, 6.40). Better understanding of the long-term clinical consequences of CMV infection in immunocompetent humans is needed to guide public health efforts for this widely prevalent infection.

IL-11 expression in retinal and corneal cells is regulated by interferon-gamma

Interleukin-11 (IL-11) is an anti-apoptotic, anti-inflammatory cytokine with hematopoietic potential. The expression and protective actions of IL-11 have not been explored in the eye. The expression of IL-11 in primary cultures of human retinal pigment epithelial (HRPE) and human corneal fibroblast (HCRF) cells were evaluated in these studies. Constitutive secretion of IL-11 was not observed in either HRPE or HCRF. TNF-alpha+IL-1 induced IL-11 secretion and this production was inhibited by NFkappaB pathway inhibitors. IFN-gamma significantly inhibited TNF-alpha and IL-1 induced IL-11 secretion and inhibitors of JAK-STAT pathway reversed this inhibition. TGF-beta induced IL-11 secretion that was blocked by TGF-beta receptor 1 inhibitor but not by IFN-gamma. RT-PCR analysis confirmed the effects of IL-1, TNF-alpha, IFN-gamma and TGF-beta on IL-11 secretion at mRNA levels. Our results demonstrate that IL-11 is dramatically up regulated in retina and cornea cells and that IFN-gamma is a physiological inhibitor of IL-11 expression.

Autologous mesenchymal stem cells produce reverse remodelling in chronic ischaemic cardiomyopathy

AIMS

The ability of mesenchymal stem cells (MSCs) to heal the chronically injured heart remains controversial. Here we tested the hypothesis that autologous MSCs can be safely injected into a chronic myocardial infarct scar, reduce its size, and improve ventricular function.

METHODS AND RESULTS

Female adult Göttingen swine (n = 15) underwent left anterior descending coronary artery balloon occlusion to create reproducible ischaemia-reperfusion infarctions. Bone-marrow-derived MSCs were isolated and expanded from each animal. Twelve weeks post-myocardial infarction (MI), animals were randomized to receive surgical injection of either phosphate buffered saline (placebo, n = 6), 20 million (low dose, n = 3), or 200 million (high dose, n = 6) autologous MSCs in the infarct and border zone. Injections were administered to the beating heart via left anterior thoracotomy. Serial cardiac magnetic resonance imaging was performed to evaluate infarct size, myocardial blood flow (MBF), and left ventricular (LV) function. There was no difference in mortality, post-injection arrhythmias, cardiac enzyme release, or systemic inflammatory markers between groups. Whereas MI size remained constant in placebo and exhibited a trend towards reduction in low dose, high-dose MSC therapy reduced infarct size from 18.2 +/- 0.9 to 14.4 +/- 1.0% (P = 0.02) of LV mass. In addition, both low and high-dose treatments increased regional contractility and MBF in both infarct and border zones. Ectopic tissue formation was not observed with MSCs.

CONCLUSION

Together these data demonstrate that autologous MSCs can be safely delivered in an adult heart failure model, producing substantial structural and functional reverse remodelling. These findings demonstrate the safety and efficacy of autologous MSC therapy and support clinical trials of MSC therapy in patients with chronic ischaemic cardiomyopathy.

Serum IL-6 levels are associated with significant coronary stenosis in cardiovascularly asymptomatic inner-city black adults in the US

OBJECTIVES AND DESIGN

The objective of this study was to explore whether increased levels of inflammatory cytokines are associated with the risk of clinically silent coronary artery disease.

SUBJECTS

Three-hundred-fifty-six black adults aged 25-54 residing in inner city of Baltimore, Maryland, United States were included in this study.

METHODS

Sociodemographics were assessed as were lipid profiles, IL-6, tumor necrosis factor-alpha (TNF-alpha), soluble intercellular adhesion molecule-1 (sICAM-1), and high-sensitivity C-reactive protein (hs-CRP) levels. Computed tomography (CT) coronary angiography was performed.

RESULTS

Coronary calcification was identified in 22.5 % participants and 14 % had significant (>or=50 %) coronary stenosis. Multiple logistic regression analyses suggested that IL-6 levels were independently associated with the presence of coronary calcification and significant coronary stenosis, while TNF-alpha, sICAM-1 and hs-CRP levels were not.

CONCLUSIONS

This study underscores a critical role for IL-6 in atherosclerosis and suggests that IL-6 may be a marker for significant coronary stenosis in cardiovascularly asymptomatic individuals.

Naturally occurring interference in Luminex assays for HLA-specific antibodies: characteristics and resolution

Substances occurring naturally in the sera of patients can interfere with Luminex antibody assays, causing increased background and changes in antibody specificity. We present data on the effectiveness of hypotonic dialysis (HD) or dithiothreitol (DTT) treatment in eliminating this interference. HD significantly increased reaction strength of positive control beads and reduced reaction strength of negative control beads. HD also improved specificity identification, determination of donor-specific antibody (DSA) strength, and crossmatch predictability compared with values in untreated serum. DTT also increased the reaction strength of positive control beads, but in most cases, further increased reactivity of negative control beads. DTT improved crossmatch predictability but to a lesser extent than did HD and may differ with specificities defined in other assays. Because interference is frequently observed in sera from highly sensitized patients, it is important to recognize and eliminate interference in Luminex antibody assays for accurate and meaningful test interpretation.

HSV immune complex (HSV-IgG: IC) and HSV-DNA elicit the production of angiogenic factor VEGF and MMP-9

Angiogenesis and inflammatory mediators are critical pathogenic factors in herpetic stromal keratitis (HSK). Since disease progresses without infectious virus, HSV-DNA and HSV-IgG complexes (HSV-IC) may contribute to HSK by triggering these factors. Production of VEGF and MMP-9 was studied in vitro using corneal epithelial cells (HCE), fibroblasts (HCRF) and macrophages (THP-1). VEGF was elevated in HCRF and THP-1 following treatment with HSV-DNA and HSV-IC. MMP-9 was elevated in THP-1 but not in corneal cells. When anti-HSV-IgG(Fab')2 complexes stimulated THP-1, MMP-9 was reduced to control levels. Pretreatment of THP-1 with anti-TLR-2 and -3 inhibited MMP-9 production. Thus, HSV-IC may stimulate THP-1 through the Fc receptor and TLRs. Proinflammatory cytokines (IL-1b, IL-6, and TNF-alpha) increased VEGF and MMP-9 in corneal cells and macrophages. These studies indicate that the continued presence of HSV-DNA and HSV-IC contribute to angiogenesis and inflammation in HSK. Thus, cytokines and TLRs may be potential targets for intervention.

The need for standardization of antiretinal antibody detection and measurement

PURPOSE

To review the current literature on the detection and measurement of antiretinal antibodies.

DESIGN

Collaborative essay.

METHODS

Literature review and interpretation.

RESULTS

There is strong evidence to suggest a role for antiretinal antibodies, particularly those targeting recoverin and alpha-enolase, in the pathogenesis of autoimmune retinopathy (AIR). Additionally, numerous other autoantibodies have been described as putative mediators of retinal degeneration and more remain to be discovered. However, assay methods described in the literature by many laboratories for the detection of circulating antiretinal antibodies have been varied and diverse, making it difficult to interpret and compare their results.

CONCLUSIONS

There is currently little standardization of laboratory methods used to detect and monitor antiretinal antibodies. To measure and monitor levels of circulating antiretinal antibodies optimally in patients with AIR, development of standardized assays with stringent internal controls is required. A multicenter collaborative and validation effort is encouraged to reach a consensus on this issue.

IFN-gamma acts as anti-angiogenic cytokine in the human cornea by regulating the expression of VEGF-A and sVEGF-R1

Inflammatory processes within the cornea are known to be associated with corneal neovascularization (CN). We examined the effects of inflammatory mediators on the expression of angiogenic factors by corneal cells. TNF-alpha and IL-1 induced VEGF-A secretion by corneal fibroblasts (HCRF) and this was inhibited significantly by IFN-gamma. Constitutively secreted VEGF-A by corneal epithelial cells (HCE) was not affected by these cytokines. Moreover, sVEGF-R1(sFlt-1) secretion by HCRF was stimulated significantly by IFN-gamma. JAK-STAT pathway inhibitor reversed the effects of IFN-gamma on VEGF-A and sFlt-1 secretion by HCRF. RT-PCR analysis showed that IFN-gamma influences the expression of VEGF-A and sFlt-1 by affecting their mRNA level. IFN-gamma inhibited TGF-beta induced VEGF-A secretion but not sVEGF-R1 secretion. This is the first report demonstrating the inhibitory and stimulatory effects of IFN-gamma on VEGF-A and sFlt-1 secretion, respectively. Our results suggest that IFN-gamma acts as an anti-angiogenic cytokine in the human cornea.

IFN-beta provides immuno-protection in the retina by inhibiting ICAM-1 and CXCL9 in retinal pigment epithelial cells

The retinal pigment epithelial (RPE) cell is a potent regulatory cell that facilitates normal physiologic processes and plays a critical role in a variety of retinal diseases. We evaluated IFN-beta production in human RPE cells through TLR signaling and investigated the effects of IFN-beta on RPE cells. RPE cells treated with poly(I:C) or infected with an RNA virus produce IFN-beta. Kinetic studies revealed that IFN-beta levels continue to increase over a 48-h period and this was associated with the up-regulation of IRF-7 gene expression, a known positive feedback molecule for IFN-beta production. Microarray analysis revealed that in IFN-beta treated cells, 480 genes of 22,283 genes were up or down-regulated by >2-fold. We hypothesize that IFN-beta induction during TLR signaling in the retina is an immunosuppressive factor produced to limit immunopathologic damage. Cytokine activation of RPE cells results in the production of the chemokines, CXCL9 and CXCL10, and the adhesion molecule, ICAM-1. Pretreatment of RPE cells with IFN-beta resulted in inhibition of ICAM-1 production and elimination of CXCL9 production. This treatment did not alter CXCL10 production. Anti-IFN-beta Ab blocked the inhibitory action of IFN-beta. Real time PCR analysis revealed that IFN-beta treatment inhibited gene expression of sICAM-1 and CXCL9. The results indicate a critical role for RPE cell derived IFN-beta in the down-regulation of CXCL9 and ICAM-1 expression in the retina and suggest that the inhibition of CXCL9 is an immuno-suppressive mechanism that protects the retina from excessive inflammation.

Gamma heavy chain disease in a patient with diabetes and chronic renal insufficiency: diagnostic assessment of the heavy chain fragment

Heavy chain diseases are rare B-cell disorders that are characterized by an overproduction of abnormal and structurally incomplete monoclonal immunoglobulin (Ig) heavy chains and are devoid of light chains. We describe a case of a 62 year-old African-American woman with a long history of poorly controlled type 2 diabetes and subsequent probable diabetic nephropathy, hypertension, and recent onset of peripheral neuropathy involving all extremities. Routine laboratory testing revealed a distinct beta spike by urine protein electrophoresis (UPEP). No serum abnormality was noted on serum protein electrophoresis (SPEP). Serum and urine immunofixation demonstrated an IgG heavy chain protein devoid of any corresponding light chains. IgG subclasses identified IgG1 as the predominant IgG component but when we added all the subclasses, the sum, 683.4 mg/dL, failed to come close to our total IgG of 1,770 mg/dL. Therefore, a urine IgG subclass determination was performed in-house and we identified a subclass 3 gamma chain. In conclusion, we portray a patient with an underlying monoclonal gamma heavy chain disease (HCD) who presented with a complex medical history. The evaluation of IgG subclasses in the context of a HCD may be limited by the capability of the test to recognize the particular IgG fragment.