Project Summary/Abstract In the US, mortality attributable to alcohol consumption continues to climb, while cannabis use and associated disorders are also becoming increasingly prevalent. Concurrent cannabis use is reported by an estimated 11% of regular alcohol consumers, and cannabis use has been linked to increased frequency and quantity of alcohol consumption. Harmful alcohol use can heighten the risk of respiratory infections, particularly community-acquired pneumonia (CAP). However, how dual alcohol and cannabis consumption influences CAP risk is unknown, and their combined impact on pulmonary immune cell function is not established. Through investigations facilitated by the Colorado Pulmonary-Alcohol Research Collaborative (CoPARC), a NIAAA- supported R24 Research Resource, we seek to unravel how dual alcohol and cannabis use exacerbate the risk of developing pulmonary infections, including CAP. Our preliminary studies indicate that harmful alcohol and cannabis exposures alter expression of genes that are critical for pathogen recognition in both airway epithelial cells (AECs) and alveolar macrophages (AMs). The focus of this proposal is to gain detailed insights into how the combination of harmful alcohol and cannabis use alter fundamental immune cell functions in pathogen recognition and clearance. Specific Aim 1 will establish the molecular signature of dual alcohol and cannabis misuse in human AECs and AMs. Studies will be performed with bronchoscopically obtained cells (AECs and AMs) and fluid from four participant types in the CoPARC biorepository, including those with alcohol use disorders (AUDs), with and without cannabis use; cannabis users; and control participants. RNA- seq will be performed to gain detailed insights into immunomodulatory changes associated with substance use. Additionally, the relationship of substance use on mucus secretion markers and inflammatory mediators will be assessed in BAL fluid. In Specific Aim 2, we will establish cooperativity between alcohol and cannabinoid (CB) receptor agonists on cellular responses to pathogens and pathogen components in human BEAS-2B cell lines (bronchial epithelium) and THP1 monocyte-derived macrophages (Macs). Cells will be treated with ? alcohol ? specific CB receptor agonists, and outcome measures will include efficiency in neutralizing and killing bacteria, modulation of TLR responsiveness, expression of immunomodulatory cytokines, and expression of MUC5AC and epithelial barrier disruption. Further functional outcomes will be studied in BEAS-2B cell lines and Macs subjected to human BAL fluid from the four participant types (as for Aim 1). Through these mutually linked aims, we will gain valuable insights into dual alcohol- and cannabis-imposed alterations in pathogen recognition.

R21AA028871

2021-08-20

2023-07-31