Impact of extreme weather events on the Infant Microbiome

Prenatal exposures to weather disasters greatly increase the risks of diseases later in life, such as asthma. These disaster-related environmental and psychological stressors may influence the human microbiome at early life and result in disturbed metabolic and immune systems. However, we still lack evidence on these important mechanisms. We have been leading a birth cohort study named Hurricane as the Origin of Later Alterations in Microbiome (HOLA) in San Juan, Puerto Rico with our collaborators in the San Juan City Hospital Research Unit and University of Puerto Rico. In this study, we recruited infants who were exposed in utero to Hurricane Maria (a category 4 storm struck Puerto Rico in late September 2017) and infants who were conceived at least 5 months after the Hurricane as controls. We are characterizing and comparing the infant nasal and gut microbiome between the two groups.

Catchment region of the HOLA cohort study in San Juan, Puerto Rico.

Sources and assembly of nasal microbiome in early life on a global scale

Current studies have primarily focused on the infant gut microbiome, studies to investigate the infant nasal microbiome have been much less. Further, current research on the infant nasal microbiome has primarily been conducted in developed countries and regions and are seldomly found in the developing regions. This is critical research disparities in this field. We established a longitudinal birth cohort with mother-infant dyads globally at three research sites: Barnes-Jewish Hospital in St. Louis, United States, San Juan City Hospital in San Juan, Puerto Rico, and University of Ghana Medical Center in Accra, Ghana. Utilizing this cohort, we will be able to investigate the maternal sources of initial nasal microbiome and their assembly in early infancy. We will also measure prenatal and postnatal environmental exposures and examine their impacts on the microbial colonization and development in the infant nose.

The airway microbiome in lung infections and diseases

We have performed several population-based studies to contribute to our knowledge on airway microbial features associated with lung infections and asthma. For examle, we applied a novel family-based study design to compare adolescents with asthma with their siblings without asthma within the same household to eliminate variations in indoor exposures among participants. In addition, we established an asthma cohort in the greater St. Louis metropolitan region and evaluated the influence of sex on the associations between the airway microbiome and asthma. To Further identify the functional role of airway microbiome in the lung inflammation and asthma, we focuses on the bacteria-virus interactions in the airway epithelium to induce lung inflammatory responses as viralrespiratory infection is the leading cause of asthma development and asthma exacerbations. We established a respiratory viral infection model in a 3-D airway organoid system. With this novel infection system, we are able to investigate interactions between airway bacteria and the respiratory viruses, such as RSV and RV.

Immunostaining of a mature airway organoid. Green: Krt5; Red: Tubulin; Blue: DAPI.