Biologic Responses to House Dust Mite Exposure in the Environmental Exposure Unit

Introduction: Allergic rhinitis (AR) is an inflammatory disease of the nasal mucosa that can be modeled using Controlled Allergen Exposure Facilities (CACF). Recently, we clinically validated the house dust mite (HDM) Environmental Exposure Unit (EEU) facility. In the current study, we aimed to assess biological responses in the blood following HDM exposure in the HDM-EEU.Methods: Fifty-five participants passed a screening visit, where they provided consent and completed a skin prick test (SPT), then attended a modest or higher HDM exposure session. Baseline and post-exposure blood samples were collected. Complete blood counts with differentials were measured, and isolated serum was used to determine Dermatophagoides farinae- and Dermatophagoides pteronyssinus-specific IgE (sIgE) and cytokine concentrations (IL-4, IL-5, IL-6, IL-10, IL-13, TNF-α).Results: HDM-allergic participants had significantly greater SPT wheal sizes than healthy controls. sIgE concentrations were significantly greater in allergic participants, with a strong correlation between Dermatophagoides farinae and Dermatophagoides pteronyssinus. Serum eosinophil counts were significantly decreased post-exposure for allergic participants. White blood cell, neutrophil, and lymphocyte counts were significantly increased for both allergic and non-allergic participants post-exposure. Serum IL-13 concentrations were significantly reduced post-exposure in allergics while TNF-α was significantly reduced in non-allergics.Conclusion: The HDM-EEU is a useful model for investigating biologic mechanisms of HDM-induced AR. Allergic participants produced measurable biological changes compared to healthy controls following allergen exposure, specifically with serum expression of eosinophils and related markers, namely IL-5, which promotes the proliferation and differentiation of eosinophils, and IL-13, a cytokine released by eosinophils. The exact mechanisms at play require further investigation.

Queering Environmental Justice: Unequal Environmental Health Burden on the LGBTQ+ Community

The LGBTQ+ (lesbian, gay, bisexual, transgender/-sexual, queer or questioning, intersex, asexual, and all subsects) population has been the target of federal and state discriminatory policies leading to high levels of institutional discrimination in the housing, employment, and health sectors. Social determinants of health such as housing conditions, economic opportunities, and access to health care may negatively and disproportionately affect the LGBTQ+ population and reduce their capacity to respond to environmental harm (e.g., obtaining necessary medical care). Social determinants of health have been shown to be associated with unequal harmful environmental exposure, primarily along lines of race/ethnicity and socioeconomic status. However, chronic diseases, such as respiratory diseases, cardiovascular disease, and cancer, associated with environmental exposure have been shown to occur in higher rates in the LGBTQ+ population than in the cisgender, heterosexual population. We explore how environmental exposures may disproportionately affect the LGBTQ+ population through examples of environmental exposures, health risks that have been linked to environmental exposures, and social institutions that could affect resilience to environmental stressors for this population. We provide recommendations for policymakers, public health officials, and researchers. (Am J Public Health. 2022;112(1):79–87. https://doi.org/10.2105/AJPH.2021.306406 )

Prevalence and Risk Factors for Retinopathy of Prematurity in China: A Systematic Review and Meta-Analysis

Background The etiology of retinopathy of prematurity (ROP) is thought to be related to genetic susceptibility and environmental exposure factors. The purpose of this article was to estimate the prevalence of ROP in mainland China and to attempt to summarize the environmental risk factors for ROP in Chinese infants. Method We searched 9 databases for articles that were published before May 29, 2021, and studies describing the prevalence and risk factors for ROP in Chinese infants were included. The fixed-effects model and the random-effects model were applied to the effect sizes (ES) and their 95% confidence intervals (CIs) with I2≤50% and I2>50% in the heterogeneity tests, respectively. Results Twenty-two separate populations were included in the meta-analysis of the prevalence of ROP. The prevalence of ROP in mainland China was 9.284% (95% CI: 6.546-12.022%). It was negatively correlated with birth weight (BW) and gestational age (GA). Fifty independent meta-analyses were observed to be related to environmental exposure factors of ROP. Thirty of the 50 meta-analyses had results that were significant at p values less than 0.05. The first three risk factors with the largest combined effect size were GA≤34 w, bronchopulmonary dysplasia (BPD) and BW≤2,000 g. Conclusions Approximately one in ten immature infants suffered from ROP. More studies need to be included. Premature babies with diseases that cause hypoxia and irregular oxygen use should be paid more attention for ROP screening.