Lung-resident type 1 conventional dendritic cells (cDC1s) are critical for initiating immune responses against foreign respiratory viruses and endogenous assaults like cancer cells. Importantly, the cDCs of each tissue display unique phenotypes and functions dictated by the environment they populate. However, our understanding of the factors that regulate cDC1 development and function in the lung is minimal. The cytokines, FMS-like tyrosine kinase 3 ligand (FLT3L), and granulocyte-macrophage stimulating factor (GM-CSF) are essential for the development of tissue-resident cDC1, but in in vitro systems, these factors are insufficient to generate cDC1s with a lung-specific phenotype. RNAseq analysis of lung cDC1 identified a clear enrichment in genes associated with transforming growth factor beta (TGF-β) signaling, a factor also known to be enriched in the airspaces of the lung. TGF-β has been previously reported to maintain DC quiescence in the lung, however, our data suggested it may also play a role in differentiation and lung specification of these cells. Based on this, I hypothesized that adding TGF-β to in vitro bone marrow (BM) cultures alongside established cytokines FLT3L and GM-CSF would generate cDC1s phenotypically and functionally similar to in vivo lung cDC1s. The addition of TGF-β, but not GM-CSF, to optimized FLT3L-BMDC cultures resulted in development of cDC1 which highly resemble lung cDC1. The development of a high throughput in vitro system that differentiates functional lung cDC1s will not only inform the in vivo factors required for development of these cells but also provides a useful platform for interrogation of lung cDC1 function and a stepping-off point to begin models for human lung cDC1 production and study.

Inequities still exist despite efforts to address racism and reduce racial disparities in mental health care. One reason for this may be clinician’s limited knowledge and guidelines on addressing and exploring the consequences of racism in clients' lives. The current study is a mixed-method study using secondary data from the Applying Theatre-Based Training Methods to Address Racism in Community-Based Mental Health Services, which surveyed 119 community mental health clinicians across Washington State in 2021. The first aim of this analysis was to examine qualitative data on clinician's perceived barriers and facilitators in broaching racial issues with clients. The second aim was to explore how these barriers and facilitators are correlated with quantitative measures of multicultural counseling knowledge and awareness. Three significant barriers emerged: 1) Clinicians not engaging in racial topics unless clients initiated; 2) Clinicians avoiding discussions of race and racism because of feeling uncomfortable or unconfident; 3) Clinician's assumptions that their racial identities would be a barrier to discussions. Three significant facilitators included: 1) Client's initiation, emotional openness, and availability to have racial conversations; 2) Relevant social events that provided an avenue to prompt discussion; 3) Clinician's willingness and intentions to address racism through asking or actively listening. There was no statistically significant correlation between either the count of perceived barriers or facilitator themes and clinician's multicultural counseling knowledge and awareness. The present research can supplement and support efforts to train clinicians in broaching racial discussions and inform clinical practice with clients from diverse backgrounds.