Efficacy and safety of a four-drug, quarter-dose treatment for hypertension: the QUARTET USA randomized trial.

New approaches are needed to lower blood pressure (BP) given persistently low control rates. QUARTET USA sought to evaluate the effect of four-drug, quarter-dose BP lowering combination in patients with hypertension. QUARTET USA was a randomized (1:1), double-blinded trial conducted in federally qualified health centers among adults with hypertension. Participants received either a quadpill of candesartan 2 mg, amlodipine 1.25 mg, indapamide 0.625 mg, and bisoprolol 2.5 mg or candesartan 8 mg for 12 weeks. If BP was >130/>80 mm Hg at 6 weeks in either arm, then participants received open label add-on amlodipine 5 mg. The primary outcome was mean change in systolic blood pressure (SBP) at 12 weeks, controlling for baseline BP. Secondary outcomes included mean change in diastolic blood pressure (DBP), and safety included serious adverse events, relevant adverse drug effects, and electrolyte abnormalities. Among 62 participants randomized between August 2019-May 2022 (n = 32 intervention, n = 30 control), mean (SD) age was 52 (11.5) years, 45% were female, 73% identified as Hispanic, and 18% identified as Black. Baseline mean (SD) SBP was 138.1 (11.2) mmHg, and baseline mean (SD) DBP was 84.3 (10.5) mmHg. In a modified intention-to-treat analysis, there was no significant difference in SBP (-4.8 mm Hg [95% CI: -10.8, 1.3, p = 0.123] and a -4.9 mmHg (95% CI: -8.6, -1.3, p = 0.009) greater mean DBP change in the intervention arm compared with the control arm at 12 weeks. Adverse events did not differ significantly between arms. The quadpill had a similar SBP and greater DBP lowering effect compared with candesartan 8 mg. Trial registration number: NCT03640312.

Nigeria healthcare worker SARS-CoV-2 serology study: Results from a prospective, longitudinal cohort.

Healthcare workers, both globally and in Nigeria, have an increased risk for SARS-CoV-2 infection compared with the general population due to higher risk contacts, including occupational exposures. In addition, primary healthcare workers represent an important group for estimating prior infection to SARS-CoV-2 because they work at the first point-of-contact for most patients yet have not been included in prior COVID-19 seroepidemiology research in Nigeria. We sought to evaluate baseline seroprevalence, rates of seroconversion (IgG- to IgG+) and seroreversion (IgG+ to IgG-), change in IgG concentration at 3- and 6-month follow-up, and factors associated with seropositivity. From June 2020 to December 2020, we conducted a longitudinal seroepidemiology study among frontline health care workers in Nigeria using a validated dried blood spot assay. Among 525 participants, mean (SD) age was 39.1 (9.7) years, 61.0% were female, and 45.1% were community health workers. The six-month follow-up rate was 93.5%. Seropositivity rates increased from 31% (95% CI: 27%, 35%) at baseline to 45% (95% CI: 40%, 49%) at 3-month follow-up, and 70% (95% CI: 66%, 74%) at 6-month follow-up. There was a corresponding increase in IgG levels from baseline (median = 0.18 ug/mL) to 3-month (median = 0.35 ug/mL) and 6-month follow-up (median = 0.59 ug/mL, Ptrend < .0001). A minority of participants reported symptoms from February 2020 until baseline (12.2%) or during 3-month (6.6%) or 6-month (7.5%) follow-up. only 1 participant was hospitalized. This study demonstrated high baseline, 3-month and 6-month follow-up prevalence of IgG antibodies to SARS-CoV-2 during the first two waves of the COVID-19 pandemic in Nigeria among a cohort of unvaccinated frontline healthcare workers, including primary healthcare workers despite low symptomatology. These results may have implications in state- and national-level disease pandemic modeling. Trial registration: NCT04158154.

Fixed-dose combination therapy-based protocol compared with free pill combination protocol: Results of a cluster randomized trial.

Fixed-dose combination (FDC) therapy is recommended for hypertension management in Nigeria based on randomized trials at the individual level. This cluster-randomized trial evaluates effectiveness and safety of a treatment protocol that used two-drug FDC therapy as the second and third steps for hypertension control compared with a protocol that used free pill combinations. From January 2021 to June 2021, 60 primary healthcare centers in the Federal Capital Territory of Nigeria were randomized to a protocol using FDC therapy as second and third steps compared with a protocol that used the same medications in free pill combination therapy for these steps. Eligible patients were adults (≥18 years) with hypertension. The primary outcome was the odds of a patient being controlled at their last visit between baseline to 6-month follow-up in the FDC group compared to the free pill group. 4427 patients (mean [SD] age: 49.0 [12.4] years, 70.5% female) were registered with mean (SD) baseline systolic/diastolic blood pressure 155 (20.6)/96 (13.1) mm Hg. Baseline characteristics of groups were similar. After 6-months, hypertension control rate improved in the two treatment protocols, but there were no differences between the groups after adjustment (FDC = 53.9% versus free pill combination = 47.9%, cluster-adjusted p = .29). Adverse events were similarly low (<1%) in both groups. Both protocols improved hypertension control rates at 6-months in comparison to baseline, though no differences were observed between groups. Further work is needed to determine if upfront FDC therapy is more effective and efficient to improve hypertension control rates.

Stakeholder perspectives on Nigeria's national sodium reduction program: Lessons for implementation and scale-up.

BACKGROUND: To reduce excess dietary sodium consumption, Nigeria's 2019 National Multi-sectoral Action Plan (NMSAP) for the Prevention and Control of Non-communicable Diseases includes policies based on the World Health Organization SHAKE package. Priority actions and strategies include mandatory sodium limits in processed foods, advertising restrictions, mass-media campaigns, school-based interventions, and improved front-of-package labeling. We conducted a formative qualitative evaluation of stakeholders' knowledge, and potential barriers as well as effective strategies to implement these NMSAP priority actions. METHODS: From January 2021 to February 2021, key informant interviews (n = 23) and focus group discussions (n = 5) were conducted with regulators, food producers, consumers, food retailers and restaurant managers, academia, and healthcare workers in Nigeria. Building on RE-AIM and the Consolidated Framework for Implementation Research, we conducted directed content qualitative analysis to identify anticipated implementation outcomes, barriers, and facilitators to implementation of the NMSAP sodium reduction priority actions. RESULTS: Most stakeholders reported high appropriateness of the NMSAP because excess dietary sodium consumption is common in Nigeria and associated with high hypertension prevalence. Participants identified multiple barriers to adoption and acceptability of implementing the priority actions (e.g., poor population knowledge on the impact of excess salt intake on health, potential profit loss, resistance to change in taste) as well as facilitators to implementation (e.g., learning from favorable existing smoking reduction and advertising strategies). Key strategies to strengthen NMSAP implementation included consumer education, mandatory and improved front-of-package labeling, legislative initiatives to establish maximum sodium content limits in foods and ingredients, strengthening regulation and enforcement of food advertising restrictions, and integrating nutrition education into school curriculum. CONCLUSION: We found that implementation and scale-up of the Nigeria NMSAP priority actions are feasible and will require several implementation strategies ranging from community-focused education to strengthening current and planned regulation and enforcement, and improvement of front-of-package labeling quality, consistency, and use.

Efficacy and safety of a quadruple ultra-low-dose treatment for hypertension (QUARTET USA): Rationale and design for a randomized controlled trial.

BACKGROUND: Over half of patients with elevated blood pressure require multi-drug treatment to achieve blood pressure control. However, multi-drug treatment may lead to lower adherence and more adverse drug effects compared with monotherapy. OBJECTIVE: The Quadruple Ultra-low-dose Treatment for Hypertension (QUARTET) USA trial was designed to evaluate whether initiating treatment with ultra-low-dose quadruple-combination therapy will lower office blood pressure more effectively, and with fewer side effects, compared with initiating standard dose monotherapy in treatment naive patients with SBP < 180 and DBP < 110 mm Hg and patients on monotherapy with SBP < 160 and DBP < 100 mm Hg. METHODS/DESIGN: QUARTET USA was a prospective, randomized, double-blind trial (ClinicalTrials.gov NCT03640312) conducted in federally qualified health centers in a large city in the US. Patients were randomly assigned (1:1) to either ultra-low-dose quadruple combination therapy or standard dose monotherapy. The primary outcome was mean change from baseline in office systolic blood pressure at 12-weeks, adjusted for baseline values. Secondary outcomes included measures of blood pressure change and variability, medication adherence, and health related quality of life. Safety outcomes included occurrence of serious adverse events, relevant adverse drug effects, and electrolyte abnormalities. A process evaluation aimed to understand provider experiences of implementation and participant experiences around side effects, adherence, and trust with clinical care. DISCUSSION: QUARTET USA was designed to evaluate whether a novel approach to blood pressure control would lower office blood pressure more effectively, and with fewer side effects, compared with standard dose monotherapy. QUARTET USA was conducted within a network of federally qualified healthcare centers with the aim of generating information on the safety and efficacy of ultra-low-dose quadruple-combination therapy in diverse groups that experience a high burden of hypertension.

Characteristics and Patterns of Retention in Hypertension Care in Primary Care Settings From the Hypertension Treatment in Nigeria Program.

Background: More than 1.2 billion adults worldwide have hypertension. High retention in clinical care is essential for long-term management of hypertension, but 1-year retention rates are less than 50% in many resource-limited settings. Objective: To evaluate short-term retention rates and associated factors among patients with hypertension in primary health care centers in the Federal Capital Territory of Nigeria. Design, Setting, and Participants: In this cohort study, data were collected by trained study staff from adults aged 18 years or older at 60 public, primary health care centers in Nigeria between January 2020 and July 2021 as part of the Hypertension Treatment in Nigeria (HTN) Program. Patients with hypertension were registered. Exposures: Follow-up visit for hypertension care within 37 days of the registration visit. Main Outcomes and Measures: The main outcome was the 3-month rolling average 37-day retention rate in hypertension care, calculated by dividing the number of patients who had a follow-up visit within 37 days of their first (ie, registration) visit in the program by the total number of registered patients with hypertension during multiple consecutive 3-month periods. Interrupted time series analyses evaluated trends in retention rates before and after the intervention phase of the HTN Program. Mixed-effects, multivariable regression models evaluated associations between patient-, site-, and area council-level factors, hypertension treatment and control status, and 37-day retention rate. Results: In total, 10 686 patients (68.3% female; mean [SD] age, 48.8 [12.7] years) were included in the analysis. During the study period, the 3-month rolling average 37-day retention rate was 41% (95% CI, 37%-46%), with wide variability among sites. The retention rate was higher among patients who were older (adjusted odds ratio [aOR], 1.01 per year; 95% CI, 1.01-1.02 per year), were female (aOR, 1.11; 95% CI, 1.01-1.23), had a higher body mass index (aOR, 1.01; 95% CI, 1.00-1.02), were in the Kuje vs the Abaji area council (aOR, 2.25; 95% CI, 1.25-4.04), received hypertension treatment at the registration visit (aOR, 1.27; 95% CI, 1.07-1.50), and were registered during the postintervention period (aOR, 1.16; 95% CI, 1.06-1.26). Conclusions and Relevance: The findings suggest that retention in hypertension care is suboptimal in primary health care centers in Nigeria, although large variability among sites was found. Potentially modifiable and nonmodifiable factors associated with retention were identified and may inform multilevel, contextualized implementation strategies to improve retention.

Hypertension Treatment in Nigeria (HTN) Program: rationale and design for a type 2 hybrid, effectiveness, and implementation interrupted time series trial.

BACKGROUND: Hypertension is the most common cardiovascular disease in Nigeria and contributes to a large non-communicable disease burden. Our aim was to implement and evaluate a large-scale hypertension treatment and control program, adapted from the Kaiser Permanent Northern California and World Health Organization HEARTS models, within public primary healthcare centers in the Federal Capital Territory, Nigeria. METHODS: A type 2 hybrid, interrupted time series design was used to generate novel information on large-scale implementation and effectiveness of a multi-level hypertension control program within 60 primary healthcare centers in the Federal Capital Territory, Nigeria. During the formative phase, baseline qualitative assessments were held with patients, health workers, and administrators to inform implementation package adaptation. The package includes a hypertension patient registry with empanelment, performance and quality reporting, simplified treatment guideline emphasizing fixed-dose combination therapy, reliable access to quality essential medicines and technology, team-based care, and health coaching and home blood pressure monitoring. Strategies to implement and adapt the package were identified based on barriers and facilitators mapped in the formative phase, previous implementation experience, mid-term qualitative evaluation, and ongoing stakeholder and site feedback. The control phase included 11 months of sequential registration of hypertensive patients at participating primary healthcare centers, followed by implementation of the remainder of the package components and evaluation over 37 subsequent, consecutive months of the intervention phase. The formative phase was completed between April 2019 and August 2019, followed by initiation of the control phase in January 2020. The control phase included 11 months (January 2020 to November 2020) of sequential registration and empanelment of hypertensive patients at participating primary healthcare centers. After completion of the control phase in November 2020, the intervention phase commenced in December 2020 and will be completed in December 2023. DISCUSSION: This trial will provide robust evidence for implementation and effectiveness of a multi-level implementation package more broadly throughout the Federal Capital Territory, which may inform hypertension systems of care throughout Nigeria and in other low- and middle-income countries. Implementation outcome results will be important to understand what system-, site-, personnel-, and patient-level factors are necessary for successful implementation of this intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT04158154 . The trial was prospectively registered on November 8, 2019.

Characteristics, treatment, and control of hypertension in public primary healthcare centers in Nigeria: baseline results from the Hypertension Treatment in Nigeria Program.

BACKGROUND: There are limited data on large-scale, multilevel implementation research studies to improve hypertension diagnosis, treatment, and control rates at the primary healthcare (PHC) level in Africa. We describe the characteristics, treatment, and control rates of patients with hypertension in public PHC centers in the Hypertension Treatment in Nigeria Program. METHODS: Data were collected from adults at least 18 years at 60 public PHC centers between January 2020 and November 2020. Hypertension treatment rates were calculated at registration and upon completion of the initial visit. Hypertension control rates were calculated based on SBP and DBPs less than 140/90 mmHg. Regression models were created to evaluate factors associated with hypertension treatment and control status. RESULTS: Four thousand, nine hundred and twenty-seven individuals [66.7% women, mean (SD) age = 48.2 (12.9) years] were included. Mean (SD) SBP was higher in men compared with women [152.9 (20.0) mmHg versus 150.8 (21) mmHg, P = 0.001]. Most (58.3%) patients were on treatment at the time of registration, and by the end of the baseline visit, 89.2% of patients were on treatment. The baseline hypertension control rate was 13.1%, and control was more common among patients who were older [adjusted OR (95% CI) 1.01 [1.01 -1.02)], women [adjusted OR (95% CI) 1.30 (1.05- 1.62)], who used fixed dose combination therapy [adjusted OR (95% CI) 1.83 (1.49 -2.26)], and had higher education levels. CONCLUSION: This baseline report of the largest facility-based hypertension study in Africa demonstrates high hypertension treatment rates but low control rates.

Integration of transcriptome analysis with pathophysiological endpoints to evaluate cigarette smoke toxicity in an in vitro human airway tissue model.

Exposure to cigarette smoke (CS) is a known risk factor in the pathogenesis of smoking-caused diseases, such as chronic obstructive pulmonary diseases (COPD) and lung cancer. To assess the effects of CS on the function and phenotype of airway epithelial cells, we developed a novel repeated treatment protocol and comprehensively evaluated the progression of key molecular, functional, and structural abnormalities induced by CS in a human in vitro air-liquid-interface (ALI) airway tissue model. Cultures were exposed to CS (diluted with 0.5 L/min, 1.0 L/min, and 4.0 L/min clean air) generated from smoking five 3R4F University of Kentucky reference cigarettes under the International Organization for Standardization (ISO) machine smoking regimen, every other day for 4 weeks (3 days per week, 40 min/day). By integrating the transcriptomics-based approach with the in vitro pathophysiological measurements, we demonstrated CS-mediated effects on oxidative stress, pro-inflammatory cytokines and matrix metalloproteinases (MMPs), ciliary function, expression and secretion of mucins, and squamous cell differentiation that are highly consistent with abnormalities observed in airways of smokers. Enrichment analysis on the transcriptomic profiles of the ALI cultures revealed key molecular pathways, such as xenobiotic metabolism, oxidative stress, and inflammatory responses that were perturbed in response to CS exposure. These responses, in turn, may trigger aberrant tissue remodeling, eventually leading to the onset of respiratory diseases. Furthermore, changes of a panel of genes known to be disturbed in smokers with COPD were successfully reproduced in the ALI cultures exposed to CS. In summary, findings from this study suggest that such an integrative approach may be a useful tool for identifying genes and adverse cellular events caused by inhaled toxicants, like CS.

Effect of concentration and duration of particulate matter exposure on the transcriptome and DNA methylome of bronchial epithelial cells.

Exposure to particulate matter (PM) from ambient air pollution is a well-known risk factor for many lung diseases, but the mechanism(s) for this is not completely understood. Bronchial epithelial cells, which line the airway of the respiratory tract, undergo genome-wide level changes in gene expression and DNA methylation particularly when exposed to fine (<2.5 µm) PM (PM2.5). Although some of these changes have been reported in other studies, a comparison of how different concentrations and duration of exposure affect both the gene transcriptome and DNA methylome has not been done. Here, we exposed BEAS-2B, a bronchial epithelial cell line, to different concentrations of PM2.5, and compared how single or repeated doses of PM2.5 affect both the transcriptome and methylome of cells. Widespread changes in gene expression occurred after cells were exposed to a single treatment of high-concentration (30 µg/cm2) PM2.5 for 24 h. These genes were enriched in pathways regulating cytokine-cytokine interactions, Mitogen-Activated Protein Kinase (MAPK) signaling, PI3K-Akt signaling, IL6, and P53. DNA methylomic analysis showed that nearly half of the differentially expressed genes were found to also have DNA methylation changes, with just a slightly greater trend toward overall hypomethylation across the genome. Cells exposed to a lower concentration (1 µg/cm2) of PM2.5 demonstrated a comparable, but more attenuated change in gene expression compared to cells exposed to higher concentrations. There were also many genes affected by lower concentrations of PM2.5, but not higher concentrations. Additionally, repeated exposure to PM2.5 (1 µg/cm2) for seven days resulted in transcriptomic and DNA methylomic changes that were distinct from cells treated with PM2.5 for only one day. Compared to single exposure, repeated exposure to PM2.5 caused a more notable degree of hypomethylation across the genome, though certain genes and regions demonstrated increased DNA methylation. The overall increase in hypomethylation, especially with repeated exposure to PM2.5, was associated with an increase in expression of ten-eleven translocation enzymes. These data demonstrate how variations in concentration and duration of PM2.5 exposure induce distinct differences in the transcriptomic and DNA methylomic profile of bronchial epithelial cells, which may have important implications in the development of both acute and chronic lung disease.

Toxicity of Ortho-phthalaldehyde Aerosols in a Human In Vitro Airway Tissue Model.

Ortho-phthalaldehyde (OPA) is a chemical disinfectant used for the high-level sterilization of heat-sensitive medical instruments. Although OPA is considered a safer alternative to glutaraldehyde, no exposure limits have been established for respiratory exposures to ensure the safety of OPA sterilization and the safe use of OPA-treated medical instruments. In order to address data gaps in the toxicological profile of OPA, we treated human in vitro air-liquid-interface (ALI) airway cultures at the air interface with various concentrations of OPA aerosols for 10 consecutive days. Temporal tissue responses were evaluated at multiple time points during the treatment phase as well as 10 days following the last exposure. The disturbance of glutathione (GSH) homeostasis occurred as early as 20 min following the first exposure, while oxidative stress persisted throughout the treatment phase, as indicated by the sustained induction of heme oxygenase-1 (HMOX-1) expression. Repeated exposures to OPA aerosols resulted in both functional and structural changes, including the inhibition of ciliary beating frequency, aberrant mucin production, decreases in airway secretory cells, and tissue morphological changes. While OPA-induced oxidative stress recovered to control levels after a 10 day recovery period, functional and structural alterations caused by the high concentration of OPA aerosols failed to fully recover over the observation period. These findings indicate that aerosolized OPA induces both transient and relatively persistent functional and structural abnormalities in ALI cultures under the conditions of the current study.

Dr. Daniel Acosta and In Vitro toxicology at the U.S. Food and Drug Administration's National Center for Toxicological Research.

For the past five years, Dr. Daniel Acosta has served as the Deputy Director of Research at the National Center for Toxicological Research (NCTR), a principle research laboratory of the U.S. Food and Drug Administration (FDA). Over his career at NCTR, Dr. Acosta has had a major impact on developing and promoting the use of in vitro assays in regulatory toxicity and product safety assessments. As Dr. Acosta nears his retirement we have dedicated this paper to his many accomplishments at the NCTR. Described within this paper are some of the in vitro studies that have been conducted under Dr. Acosta's leadership. These studies include toxicological assessments involving developmental effects, and the development and application of in vitro reproductive, heart, liver, neurological and airway cell and tissue models.

Variation in doses and duration of particulate matter exposure in bronchial epithelial cells results in upregulation of different genes associated with airway disorders.

Exposure to particulate matter < 2.5 µm (PM2.5) is associated with a variety of airway diseases. Although studies have demonstrated that high doses of PM2.5 cause cytotoxicity and changes to gene expression in bronchial epithelial cells, the effect of lower doses and repeated exposure to PM2.5 are less well studied. Here, we treated BEAS-2B cells with varying doses of PM2.5 for 1-7 days and examined the expression of a variety of genes implicated in airway disorders. At high doses, PM2.5 increased the expression of IL6, TNF, TSLP, CSF2, PTGS2, IL4R, and SPINK5. Other genes such as ADAM33, ORMDL3, DPP10 and CYP1A1, however, were increased by PM2.5 at much lower doses (≤1 µg/cm2). Repeated exposure to PM2.5 at 1 or 5 µg/cm2 every day for 7 days increased the sensitivity and magnitude of change for all of the aforementioned genes. Genes such as IL13 and TGFB1, increased only when cells were repeatedly exposed to PM2.5. Treatment with an antioxidant, or inhibitors to aryl hydrocarbon receptor or NF-κB attenuated the effect of PM2.5. These data demonstrate that PM2.5 exerts pleiotropic actions that differ by dose and duration that affect a variety of genes important to the development of airway disease.

Loss of CDKN2B Promotes Fibrosis via Increased Fibroblast Differentiation Rather Than Proliferation.

Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease characterized by excessive scarring and fibroblast activation. We previously showed that fibroblasts from patients with IPF are hypermethylated at the CDKN2B gene locus, resulting in decreased CDKN2B expression. Here, we examine how diminished CDKN2B expression in normal and IPF fibroblasts affect fibroblast function, and how loss of CDKN2B contributes to IPF pathogenesis. We first confirmed that protein expression of CDKN2B was diminished in IPF lungs in situ. Loss of CDKN2B was especially notable in regions of increased myofibroblasts and fibroblastic foci. The degree of CDKN2B hypermethylation was particularly elevated in patients with radiographic honeycombing, a marker of more advanced fibrosis, and increased DNA methylation correlated with decreased expression. Although CDKN2B is traditionally considered a cell cycle inhibitor, loss of CDKN2B did not result in an increase in fibroblast proliferation, but instead was associated with an increase in myofibroblast differentiation. An increase in myofibroblast differentiation was not observed when CDKN2A was silenced. Loss of CDKN2B was associated with an increase in the transcription factors serum response factor and myocardin-related transcription factor A, and overexpression of CDKN2B in IPF fibroblasts inhibited myofibroblast differentiation. Finally, decreased CDKN2B expression was noted in fibroblasts from a murine model of fibrosis, and Cdkn2b-/- mice developed greater histologic fibrosis after bleomycin injury. These findings identify a novel function for CDKN2B that differs from its conventional designation as a cell cycle inhibitor and demonstrate the importance of this protein in pulmonary fibrosis.

Genetic determinants in the development of sensitization to environmental allergens in early childhood.

Sensitization to environmental allergens remains one of the strongest risk factors for asthma, and there is likely a genetic basis. We sought to identify genetic determinants for the development of allergic sensitization to environmental allergens, particularly cockroach allergen, in early childhood. A total of 631 children with the information about genotypic data on 895 single nucleotide polymorphisms (SNPs) in 179 candidate genes were selected from an existing dataset (Boston Birth Cohort). Genetic analysis was performed for allergic sensitizations among all subjects and sub-population, Black/African, respectively. Eight SNPs in seven genes showed significant association with allergic sensitization with P < 0.05, including two top SNPs, rs7851969 in JAK2 (P = 0.003) and rs11739089 in CNOT6 (P = 0.008). When analyses were specifically performed for cockroach sensitization, 16 SNPs in 13 genes showed P < 0.05, including five genes with SNPs at P < 0.01 (JAK1, JAK3, IL5RA, FCER1A, and ADAM33). Particularly, haplotype analyses demonstrated that multiple-haplotypes in FCER1A were significantly associated with cockroach sensitization with the strongest association for a 2-marker haplotype (rs6665683T-rs12136904T, P = 0.001). Furthermore, SNP rs6665683 was marginally associated with the levels of cockroach allergen specific IgE. When a similar analysis was performed for house dust mite, four SNPs in three genes (JAK2, MAML1, and NOD1) had P < 0.01. Of these, JAK2 appeared to be an only gene showing association across the sensitizations we analyzed. Some of findings were further validated when analysis was limited to black population. Our study identified several loci that may confer the susceptibility to allergic sensitization, and suggested that sensitization to allergens may depend on their unique loci.

ADAM metallopeptidase domain 33 (ADAM33): a promising target for asthma.

Over the last few years, a significant progress has been made in understanding the role of a disintegrin and metalloproteinase 33 (ADAM33) in asthma. The previous observations for the association with asthma have been replicated in over 33 different population samples worldwide. We and others have performed association analysis and meta-analysis and provided further evidence that several polymorphisms in the ADAM33 are risk factors for asthma, especially in the Asian population. Further, several studies have suggested that alterations in epigenetic marks alter the patterns of DNA methylation of ADAM33 and result in potentially adverse biological effects. Finally, while the biological activities of ADAM33 are as yet unknown, ADAM33 may play a possible role in airway remodeling because of its high expression in epithelium, myo/fibroblasts, and airway smooth muscle cells (ASMCs) and its role in promoting angiogenesis and stimulating cell proliferation and differentiation. Thus, ADAM33 represents a promising target for asthma. However, further investigations are clearly needed to discover functional ADAM33 gene polymorphisms and the role of genetic/epigenetic factors in conferring genetic susceptibility to environmental exposure induced asthma as well as biological function in asthma. This, in turn, will unlock the possibility of ADAM33 as a target for asthma therapy.

Aryl hydrocarbon receptor (AhR) modulates cockroach allergen-induced immune responses through active TGFß1 release.

BACKGROUND: Aryl hydrocarbon receptor (AhR), a multifunctional regulator that senses and responds to environmental stimuli, plays a role in normal cell development and immune regulation. Recent evidence supports a significant link between environmental exposure and AhR in the development of allergic diseases. We sought to investigate whether AhR plays a role in mediating cockroach allergen-induced allergic immune responses. METHODS: AhR expression in human lung fibroblasts from asthmatic and healthy individuals and in cockroach extract (CRE) treated human lung fibroblasts (WI-38) was examined. The role of AhR in modulating CRE induced TGFß1 production was investigated by using AhR agonist, TCDD, antagonist CH122319, and knockdown of AhR. The role of latent TGFß1 binding protein-1 (LTBP1) in mediating TCDD induced active TGFß1 release was also examined. RESULTS: AhR expression was higher in airway fibroblasts from asthmatic subjects as compared to healthy controls. AhR in fibroblasts was activated by TCDD with an increased expression of cyp1a1 and cyp1b1. Increased AhR expression was observed in CRE-treated fibroblasts. Importantly, CRE induced TGFß1 production in fibroblasts was significantly enhanced by TCDD but inhibited by CH122319. Reduced TGFß1 production was further confirmed in fibroblasts with AhR knockdown. Moreover, AhR knockdown inhibited CRE induced fibroblast differentiation. Furthermore, TCDD induced active TGFß1 release was significantly inhibited by LTBP1 knockdown. CONCLUSION: These results provide evidence for the role of AhR in modulating cockroach allergen-induced immune responses through controlling the active TGFß1 release, suggesting a possible synergistic effect between exposure to allergens and environmental chemicals on the development of allergic diseases.

Increased expression of ADAM33 protein in asthmatic patients as compared to non-asthmatic controls.

BACKGROUND & OBJECTIVES: ADAM33 is a member of a family of genes that encode membrane-anchored proteins with a disintegrin and a metalloprotease domain, primarily expressed in lung fibroblasts and bronchial smooth muscle cells. ADAM33 has been identified as a risk factor for asthma and is known as a gene associated with airway remodelling. The present study was conducted with the aims to investigate the expression of ADAM33 protein in patients of asthma and non-asthmatic controls, and to assess if the expression of ADAM33 protein relates with severity of asthma. METHODS: A total of 35 subjects, including 27 patients with asthma and eight non-asthmatic controls were included using Global Initiative for Asthma guidelines 2005. Bronchial biopsy tissues were collected and paraffin sections were made to store all study samples. Immunohistochemistry was performed using standardized protocol. RESULTS: An increase in expression of ADAM33 protein was observed in the epithelium, smooth muscle and mesenchymal cells of asthma cases when compared to controls but there was no relationship with severity of asthma. INTERPRETATION & CONCLUSIONS: A higher expression of ADAM33 protein was seen in asthma patients compared to controls. Large prospective studies need to be done with adequate study design to confirm these preliminary finding.

Haplotypic association of ADAM33 (T+1, S+1 and V - 3) gene variants in genetic susceptibility to asthma in Indian population.

AIM: The aim of this study was to find out if the ADAM33 gene polymorphisms T+1(A>G), S+1(T>A) and V - 3(C>T) and their haplotypes play any role in genetic susceptibility to asthma. SUBJECTS AND METHODS: Three hundred and ninety healthy controls and 386 asthmatic patients from Lucknow, India, were recruited for the study. Subjects were aged between 1-50 years. Among total recruited asthma cases, 95 (24.6%) had mild intermittent asthma, 235 (60.9%) had mild persistent asthma and 56 (14.5%) had moderate persistent asthma. Genotyping was carried out using the Polymerase Chain Reaction and Restriction Fragment Length polymorphism (PCRRFLP) method. RESULTS: No significant differences in the genotype or allele frequencies of ADAM33 gene polymorphisms between asthmatic patients and healthy controls were found [p-value>0.05 (All the p-values were Bonferroni corrected)]. Also, no association of studied SNPs with the severity of the disease asthma was observed. However, the TTA haplotype was observed to be associated with asthma (OR = 3.4; 95%CI = 1.4-8.7; p = 0.002). CONCLUSIONS: SNPs, T+1, S+1 and V - 3 do not individually confer any significant risk of asthma or its severity, but haplotype analysis suggests all three polymorphisms together play an important role in the disease of asthma.

Environmental risk factors for persistent asthma in Lucknow.

OBJECTIVE: To identify the risk factors for persistent asthma among common environmental exposures, like ambient air pollutants and second hand smoke, animals, place of residence, decreased ventilation, dust, as well as history of allergic conditions like rhinitis, dermatitis and family history of asthma in children. METHODS: This hospital-based, cross-sectional study was conducted after institutional ethical clearance. Children aged 1-12 y with asthma were recruited after parental consent. Children were classified into asthma severity categories according to GINA 2002 and level of control categories according to GINA 2009 guidelines. Adjusted logistic regression analysis was used to identify factors associated with persistent asthma. RESULTS: From August 2008 through October 2010, 205 asthmatic children were recruited of which 73 (35.60 %) had intermittent and 132 (64.40 %) had persistent asthma. Asthma was controlled in 19 (9.26 %), partly controlled in 90 (43.90 %) and uncontrolled in 96 (46.82 %). Patients with persistent asthma were more likely to have uncontrolled asthma (OR = 8.28; 95 % CI: 2.43-31.01; p < 0.001). Adjusting for age, sex, socioeconomic status and place of residence, persistent asthma was associated with residence within 1.5 km from heavy traffic (OR = 4.58; 95%CI: 2.18-9.59; p < 0.001) and father smoking indoors >5 cigarettes or "bidi"/day (OR = 17.76; 95 % CI: 1.85-170.76; p = 0.01). CONCLUSIONS: Since patients with persistent asthma are more likely to have uncontrolled asthma and since persistent asthma is associated with residence closer to heavy traffic and exposure to second hand smoke, minimizing exposures to these may help in better asthma control.