The use of environmental exposure chambers in studies related to ocular surface effects.

PURPOSE OF REVIEW: The potential of allergen challenges using environmental exposure facilities in allergic conjunctivitis drug development and more recently its implication on the diagnosis of the united airways concept have been emphasized in the recent literature. This study aims to present an overview of new and important data in this field. RECENT FINDINGS: Standardized methodologies for ocular surface assessment during allergen challenges were described. The Total Ocular Symptom Score (TOSS) is the main validated questionnaire used for the assessment of ocular surface during allergen challenges. It combines patient and investigator assessments for more accurate conjunctival response and was extensively used in clinical research and daily practice. Environmental Exposure Chambers (EECs) studies aim to conduct tight-controlled challenges to a stable and well defined allergen airborne concentration, closer to natural exposure to evaluate the efficacy of nonpharmaceutical and antiallergic treatments. Recent studies showed a good correlation between ocular symptoms elicited by EEC and those assessed during natural exposure. These validated methods allow to investigate the efficacy of novel pharmacotherapies for allergic conjunctivitis and allergen immunotherapy (AIT) in a real-world model of allergen exposure. SUMMARY: This study aims to summarize novel data regarding the impact of EECs in studying pathophysiology and drug efficacy in the context of existing clinical protocols related to ocular surface effects. In this regard, studies comparing conjunctival response during natural and EEC exposures in patients with pollen-induced conjunctivitis aimed to demonstrate better outcomes in tight-controlled exposures mimicking natural exposure. Because allergen challenges are widely implemented in allergy treatment, this article will focus on the most important outcomes and the evolution of treatments for allergic conjunctivitis.

Aeroallergen Monitoring by the National Allergy Bureau: A Review of the Past and a Look Into the Future.

Monitoring aeroallergens has a long history within the American Academy of Allergy, Asthma & Immunology. The Aeroallergen Network of the National Allergy Bureau is composed mainly of members of the American Academy of Allergy, Asthma & Immunology, whose objectives are to enhance the knowledge of aerobiology and its relationship to allergy, increase the number of certified stations, maintain the standardization and quality of aerobiology data, improve the alert and forecast reporting system, and increase ties with other scientific entities inside and outside the United States. The public has a keen interest in pollen counts and pollen forecasts, as do many health professionals in the allergy community. In this review, we explore the past, present, and future of allergen monitoring with a focus on methods used for sampling, the training of those performing the analysis, and emerging technologies in the field. Although the development of automated samplers with machine intelligence offers great promise for meeting the goal of a fully automated system, there is still progress to be made regarding reliability and affordability.

Immunomodulatory Actions of Cannabinoids: Clinical Correlates and Therapeutic Opportunities for Allergic Inflammation.

Endogenously produced cannabinoids as well as phytocannabinoids broadly exhibit anti-inflammatory actions. Recent emergence of cannabis for multiple medical issues combined with reports on potent immunomodulatory actions of distinct components has underscored the therapeutic potential of cannabis. Although synthetic cannabinoids that are based on structural similarities to the existing class of cannabinoids have been on the rise, their application in therapeutics have been limited owing to toxicity concerns. Herein, we review the current literature that details the immunomodulatory actions of cannabinoids. Further, we highlight the complexities of cannabinoid biology and examine the potential inflammatory risks associated with the use of cannabis including potential for toxic interactions between distinct constituents of cannabis.

Diretriz Latino-americana sobre o Diagnóstico e Tratamento da Alergia Ocular ­ Em nome da Sociedade Latinoamericana de Alergia, Asma e Imunologia (SLAAI) / Latin American Guideline on the Diagnosis and Treatment of Ocular Allergy ­ On behalf of the Latin American Society of Allergy, Asthma and Immunology (SLAAI)

A alergia ocular, também conhecida como conjuntivite alérgica (CA), é uma reação de hipersensibilidade mediada por imunoglobulina E (IgE) do olho desencadeada por aeroalérgenos, principalmente ácaros da poeira doméstica e pólen de gramíneas. Os sintomas geralmente consistem em prurido ocular ou periocular, lacrimejamento e olhos vermelhos que podem estar presentes durante todo o ano ou sazonalmente. A alergia ocular tem frequência elevada, é subdiagnosticada e pode ser debilitante para o paciente. É potencialmente danosa para a visão, nos casos em que ocasiona cicatrização corneana grave, e na maioria dos pacientes associa-se a outros quadros alérgicos, principalmente rinite, asma e dermatite atópica. É classificada em conjuntivite alérgica perene, conjuntivite alérgica sazonal, ceratoconjuntivite atópica e ceratoconjuntivite vernal. O diagnóstico procura evidenciar o agente etiológico e a confirmação se dá pela realização do teste de provocação conjuntival. O tratamento baseia-se em evitar o contato com os desencadeantes, lubrificação, anti-histamínicos tópicos, estabilizadores de mastócitos, imunossupressores e imunoterapia específica com o objetivo de obter o controle e prevenir as complicações da doença.

Ocular allergy, also known as allergic conjunctivitis, is an immunoglobulin E-mediated hypersensitivity reaction of the eye triggered by airborne allergens, primarily house dust mites and grass pollen. Symptoms usually consist of ocular or periocular itching, watery eyes, and red eyes that may be present year-round or seasonally. Ocular allergy has a high frequency, is underdiagnosed, and can be debilitating for the patient. It is potentially harmful to vision in cases of severe corneal scarring, and in most patients, it is associated with other allergic conditions, especially rhinitis, asthma, and atopic dermatitis. It is classified as perennial allergic conjunctivitis, seasonal allergic conjunctivitis, atopic keratoconjunctivitis, and vernal keratoconjunctivitis. Diagnosis seeks to identify the etiologic agent, and confirmation is given by conjunctival provocation testing. Treatment is based on avoiding contact with triggers, lubrication, topical antihistamines, mast cell stabilizers, immunosuppressants, and specific immunotherapy with the aim of achieving control and preventing disease complications.

The influence of sea breeze on mold spore dispersion.

Background: Many allergists consider the ocean breeze to be free of allergens and recommend visits to the coast for relief; however, the coast may perpetuate an allergenic environment. Objective: This study investigated the sea breeze's impact on spore dispersion between coastal and inland sites, and the potential implications of sea breeze on human health and coastal resources. Methods: Spore sampling occurred during 2006 by using pollen samplers. Samplers were located at the Rutgers University Institute of Marine and Coastal Sciences Marine Field Station and the Rutgers University Pinelands Field Station. Statistical analysis was performed on the spore data to compare concentrations from the various locations. The effect of sea breeze circulation on particulate matter was analyzed from meteorological data collected in 2006. Sea breeze data were collected from simulations, Doppler radar, and meteorological towers at varying heights. Results: There was no significant difference between the total spore concentration at the New Jersey coast and the New Jersey Pinelands canopy. Conclusion: Sea breeze has been shown to favor aerobiologic transfers from coastal seawater to land, but the immediate environment (floor) still remains a primary determinant of affecting an individual's allergic airway disease. Results of some studies have shown that coastal environments may favor the onset allergic airway, but in our study this seemed to be equivalent to the floor (or immediate locale) of an individual affected with allergy. However, the sea breeze effect seemed to have the ability to impact allergic airway disease (AAD) populations not only living along the coasts but of those living up to 130 km inland and potentially those living in the Philadelphia metropolitan area.

Higher airborne pollen concentrations correlated with increased SARS-CoV-2 infection rates, as evidenced from 31 countries across the globe.

Pollen exposure weakens the immunity against certain seasonal respiratory viruses by diminishing the antiviral interferon response. Here we investigate whether the same applies to the pandemic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is sensitive to antiviral interferons, if infection waves coincide with high airborne pollen concentrations. Our original hypothesis was that more airborne pollen would lead to increases in infection rates. To examine this, we performed a cross-sectional and longitudinal data analysis on SARS-CoV-2 infection, airborne pollen, and meteorological factors. Our dataset is the most comprehensive, largest possible worldwide from 130 stations, across 31 countries and five continents. To explicitly investigate the effects of social contact, we additionally considered population density of each study area, as well as lockdown effects, in all possible combinations: without any lockdown, with mixed lockdown-no lockdown regime, and under complete lockdown. We found that airborne pollen, sometimes in synergy with humidity and temperature, explained, on average, 44% of the infection rate variability. Infection rates increased after higher pollen concentrations most frequently during the four previous days. Without lockdown, an increase of pollen abundance by 100 pollen/m3 resulted in a 4% average increase of infection rates. Lockdown halved infection rates under similar pollen concentrations. As there can be no preventive measures against airborne pollen exposure, we suggest wide dissemination of pollen-virus coexposure dire effect information to encourage high-risk individuals to wear particle filter masks during high springtime pollen concentrations.

The Importance of Binomial Nomenclature for the Identification of Pollen Aeroallergens.

The diagnosis and treatment of atopic disorders associated with specific aerobiological triggers require basic botanical training. However, the identification of specific pollen can often be confounded by broad naming conventions that range from categorized colloquial to scientific names based on either higher taxonomic levels or, in some cases, binomial nomenclature. Physicians specializing in allergy often lack a comprehensive understanding with respect to plant taxonomy and botanical nomenclature that are critical skills required for clinical practice and research programs evaluating pollen and airborne fungal spores. In addition, binomial and current family designation and synonyms, including author citation are often misused, causing a misinterpretation of existing plants species or pollen types. It is critical that the correct botanical name is linked to a validated specimen and scientific naming conventions are used where possible by the clinician and researcher. In relation to pollen identification, we propose that clinicians and researchers should provide the currently accepted binomial nomenclature, offer relevant synonyms, and use the Angiosperm Phylogeny Group names.

Anthropogenic climate change is worsening North American pollen seasons.

Airborne pollen has major respiratory health impacts and anthropogenic climate change may increase pollen concentrations and extend pollen seasons. While greenhouse and field studies indicate that pollen concentrations are correlated with temperature, a formal detection and attribution of the role of anthropogenic climate change in continental pollen seasons is urgently needed. Here, we use long-term pollen data from 60 North American stations from 1990 to 2018, spanning 821 site-years of data, and Earth system model simulations to quantify the role of human-caused climate change in continental patterns in pollen concentrations. We find widespread advances and lengthening of pollen seasons (+20 d) and increases in pollen concentrations (+21%) across North America, which are strongly coupled to observed warming. Human forcing of the climate system contributed ∼50% (interquartile range: 19-84%) of the trend in pollen seasons and ∼8% (4-14%) of the trend in pollen concentrations. Our results reveal that anthropogenic climate change has already exacerbated pollen seasons in the past three decades with attendant deleterious effects on respiratory health.

Allergenic Pollen Season Variations in the Past Two Decades Under Changing Climate in the United States.

Prevalence of allergic diseases has been increasing due to multiple factors, among which climate change has had the most impact. Climate factors increase production of pollen, which also exhibits increased allergenicity. Also, as a result of climate change, there has been a shift in flowering phenology and pollen initiation causing prolonged pollen exposure. Various numerical models have been developed to understand the effect of climate change on pollen emission and transport and the impact on allergic airway diseases.

Flavonoid and cannabinoid impact on the ocular surface.

PURPOSE OF REVIEW: To evaluate the impact of flavonoids and cannabinoids as anti-inflammatory and antiallergic treatments on the anterior surface of the eye. RECENT FINDINGS: Allergic conjunctivitis and dry eye syndrome are common ocular surface diseases that have been treated with traditional pharmacological measures, e.g. corticosteroids, antihistamines. Given the side-effect profiles of these medications and the growing interest in complementary treatment modalities as part of integrative medical interventions, well known flavonoids, such as quercetin and catechin, are under investigation for topical and systemic application methods for relief. As flavonoid derivatives, pycnogenol and epigallocatechin gallate have alleviated dry eye symptoms, including lacrimal gland inflammation, tear secretion, and the stability of the tear film. Research on ocular cannabinoid receptors and response to synthetic cannabinoids are also being considered for therapy of anterior ocular disorders. The expansion of herbal formulations provides a framework for future treatment regimens for ocular surface disorders. SUMMARY: Flavonoids and cannabinoids show promise as potential complementary treatment for allergic diseases because of their anti-inflammatory and antiallergic properties. Several studies implementing ocular and systemic application of these compounds show potential in becoming adjuvant treatment strategies for improving quality of life while also managing ocular surface disease processes.

The allergic eye: recommendations about pharmacotherapy and recent therapeutic agents.

PURPOSE OF REVIEW: Ocular allergies affect an estimated 40% of the population, 98% of which are because of allergic conjunctivitis. With the current advent of both repurposed drugs for ocular allergies, as well as novel drugs and methods of administration, there is a need for an updated review of current available medications. A clear characterization of each treatment will ultimately allow treating physicians to restore patients' quality of life and decrease burden of disease. RECENT FINDINGS: Currently, there are a number of reformulated antihistamines, with cetrizine being the most recent ophthalmic solution available. Nevertheless, there is ongoing research in the field of immunotherapy, steroids, flavonoids, cannabis, and drug-delivery systems. SUMMARY: Although dual-activity agents remain the keystone for treatment, newer drugs and drug-delivery systems offer other novel directions for delivering appropriate relief with minimal adverse effects.

Development of a semi-mechanistic allergenic pollen emission model.

Modeling pollen emission processes is crucial for studying the spatiotemporal distributions of airborne allergenic pollen. A semi-mechanistic emission model was developed based on mass balance of pollen grain fluxes in the surroundings of allergenic plants. The emission model considers direct emission and resuspension and accounts for influences of temperature, wind velocity, and relative humidity. Modules of this emission model have been developed and parameterized with multiple years of pollen count observations to provide pollen season onset and duration, hourly flowering likelihood, and vegetation coverage for oak and ragweed, as two examples. The simulated spatiotemporal pattern of pollen emissions generally follows the corresponding pattern of area coverage of allergenic plants and diurnal pattern of hourly flowering likelihood. It is found that oak pollen emissions start from the Southern part of the Contiguous United States (CONUS) in March and then shift gradually toward the Northern CONUS, with a maximum emission flux of 5.8 × 106 pollen/(m2 h). On the other hand, ragweed pollen emissions start from the Northern CONUS in August and then shift gradually toward the Southern CONUS. The mean ragweed emission flux during August to September can increase up to 2.4 × 106 pollen/(m2 h). This emission model is robust with respect to the input parameters for oak and ragweed. Qualitative evaluations of the model performance indicated that the simulated pollen emission is strongly correlated with the plant coverages and observed pollen counts. This model could also be applied to other pollen species given the relevant parameters.

Seasonal ocular allergy and pollen counts.

PURPOSE OF REVIEW: The purpose of the article is to provide a historical overview of literature regarding pollen sensitization and ocular allergy with an emphasis on developments that have occurred over the past 5 years. RECENT FINDINGS: Currently, pollen studies have examined the molecular and cellular pathways involved in initiating allergic conjunctivitis to find targets for therapeutics. Studies have also documented the threshold, linear increase and plateau point in the relationship between pollen levels and allergic conjunctivitis symptoms. SUMMARY: Traditionally, intact pollen grains are counted as a means of correlating patient symptoms to allergen exposure. However, establishing a dose-response relationship between pollen grain exposure and allergic conjunctivitis has proven to be difficult. It has been observed that ocular allergies induce a two-fold response including early-phase and late-phase IgE-mediated reactions. Sensitization itself is a combination of pollen exposure over time in genetically predisposed individual. However, symptoms appear to reach an asymptotic point at which clinical severity plateaus. More studies are needed to clearly define differences in pollen sensitization by plant species.

Allergenic pollen season variations in the past two decades under changing climate in the United States.

Many diseases are linked with climate trends and variations. In particular, climate change is expected to alter the spatiotemporal dynamics of allergenic airborne pollen and potentially increase occurrence of allergic airway disease. Understanding the spatiotemporal patterns of changes in pollen season timing and levels is thus important in assessing climate impacts on aerobiology and allergy caused by allergenic airborne pollen. Here, we describe the spatiotemporal patterns of changes in the seasonal timing and levels of allergenic airborne pollen for multiple taxa in different climate regions at a continental scale. The allergenic pollen seasons of representative trees, weeds and grass during the past decade (2001-2010) across the contiguous United States have been observed to start 3.0 [95% Confidence Interval (CI), 1.1-4.9] days earlier on average than in the 1990s (1994-2000). The average peak value and annual total of daily counted airborne pollen have increased by 42.4% (95% CI, 21.9-62.9%) and 46.0% (95% CI, 21.5-70.5%), respectively. Changes of pollen season timing and airborne levels depend on latitude, and are associated with changes of growing degree days, frost free days, and precipitation. These changes are likely due to recent climate change and particularly the enhanced warming and precipitation at higher latitudes in the contiguous United States.

Current options and emerging therapies for anterior ocular inflammatory disease.

PURPOSE OF REVIEW: Ophthalmic disorders are highly prevalent in the United States, with approximately 3.5 million individuals aged at least 40 either blind or having impaired vision. This article reviews the current leading agents and pipeline therapies for the treatment of anterior ocular inflammatory disease (AOID). RECENT FINDINGS: There has been great progress in the understanding of ocular pathophysiology in recent years. Although current treatments for AOID are effective and well tolerated in many patients, a continued demand persists for more efficacious alternatives to the limited modalities available to clinicians. SUMMARY: Several promising modalities for AOID, particularly for allergic conjunctivitis, immune treatments for uveitis and dry eye syndrome are in late-stage development that could offer optimal treatment paradigm once available in the clinic.

Associations between ozone, PM2.5, and four pollen types on emergency department pediatric asthma events during the warm season in New Jersey: a case-crossover study.

BACKGROUND: Asthma is one of the most common chronic diseases among school-aged children in the United States. Environmental respiratory irritants exacerbate asthma among children. Understanding the impact of a variety of known and biologically plausible environmental irritants and triggers among children in New Jersey - ozone, fine particulate matter (PM2.5), tree pollen, weed pollen, grass pollen and ragweed - would allow for informed public health interventions. METHODS: Time-stratified case-crossover design was used to study the transient impact of ozone, PM2.5 and pollen on the acute onset of pediatric asthma. Daily emergency department visits were obtained for children aged 3-17 years with a primary diagnosis of asthma during the warm season (April through September), 2004-2007 (inclusive). Bi-directional control sampling was used to select two control periods for each case for a total of 65,562 inclusion days. Since the period of exposure prior to emergency department visit may be the most clinically relevant, lag exposures were investigated (same day (lag0), 1, 2, 3, 4, and 5 as well as 3-day and 5-day moving averages). Multivariable conditional logistic regression controlling for holiday, school-in-session indicator, and 3-day moving average for temperature and relative humidity was used to examine the associations. Odds ratios are based on interquartile range (IQR) increases or 10 unit increases when IQR ranges were narrow. Single-pollutant models as well as multipollutant models were examined. Stratification on gender, race, ethnicity and socioeconomic status was explored. RESULTS: The associations with ozone and PM2.5 were strongest on the same day (lag0) of the emergency department visit (RR IQR=1.05, 95% CI 1.04-1.06) and (RR IQR=1.03, 95% CI 1.02-1.04), respectively, with a decreasing lag effect. Tree and weed pollen were associated with pediatric ED visits; the largest magnitudes of association was with the 5-day average (RR IQR=1.23, 95% CI 1.21-1.25) and (RR 10=1.13, 95% CI 1.12-1.14), respectively. Grass pollen was only minimally associated with the outcome while ragweed had a negative association. CONCLUSIONS: The ambient air pollutant ozone is associated with increases in pediatric emergency department asthma visits during the warm weather season. The different pollen types showed different associations with the outcome. High levels of tree pollen appear to be an important risk factor in asthma exacerbations.

Climate change effect on Betula (birch) and Quercus (oak) pollen seasons in the United States.

Climatic change is expected to affect the spatiotemporal patterns of airborne allergenic pollen, which has been found to act synergistically with common air pollutants, such as ozone, to cause allergic airway disease (AAD). Observed airborne pollen data from six stations from 1994 to 2011 at Fargo (North Dakota), College Station (Texas), Omaha (Nebraska), Pleasanton (California), Cherry Hill and Newark (New Jersey) in the US were studied to examine climate change effects on trends of annual mean and peak value of daily concentrations, annual production, season start, and season length of Betula (birch) and Quercus (oak) pollen. The growing degree hour (GDH) model was used to establish a relationship between start/end dates and differential temperature sums using observed hourly temperatures from surrounding meteorology stations. Optimum GDH models were then combined with meteorological information from the Weather Research and Forecasting (WRF) model, and land use land coverage data from the Biogenic Emissions Land use Database, version 3.1 (BELD3.1), to simulate start dates and season lengths of birch and oak pollen for both past and future years across the contiguous US (CONUS). For most of the studied stations, comparison of mean pollen indices between the periods of 1994-2000 and 2001-2011 showed that birch and oak trees were observed to flower 1-2 weeks earlier; annual mean and peak value of daily pollen concentrations tended to increase by 13.6%-248%. The observed pollen season lengths varied for birch and for oak across the different monitoring stations. Optimum initial date, base temperature, and threshold GDH for start date was found to be 1 March, 8 °C, and 1,879 h, respectively, for birch; 1 March, 5 °C, and 4,760 h, respectively, for oak. Simulation results indicated that responses of birch and oak pollen seasons to climate change are expected to vary for different regions.

Climate change and allergic disease.

Allergies are prevalent throughout the United States and impose a substantial quality of life and economic burden. The potential effect of climate change has an impact on allergic disorders through variability of aeroallergens, food allergens and insect-based allergic venoms. Data suggest allergies (ocular and nasal allergies, allergic asthma and sinusitis) have increased in the United States and that there are changes in allergies to stinging insect populations (vespids, apids and fire ants). The cause of this upward trend is unknown, but any climate change may induce augmentation of this trend; the subspecialty of allergy and immunology needs to be keenly aware of potential issues that are projected for the near and not so distant future.