Idiopathic Pulmonary Fibrosis (IPF) is a chronic lung disease that leads to progressive scarring of the tissue. Over time, this scarring prevents the lungs from properly expanding, limiting the amount of oxygen that reaches the rest of the body. As the oxygen levels decrease, vital organs shut down, resulting in death. The exact cause of IPF remains unknown, and there are no cures. Existing treatments, such as lung transplantation and supportive medicine, focus on relieving symptoms and slowing disease progression. This project aims to identify the cellular pathways involved in IPF and discover whether disease progression can be interrupted before fibrosis fully develops. To achieve this, we designed a GelMA and Collagen Type 1 hydrogel mixture that replicates the mechanical stiffness (2-8 kPa) and collagen structure of both healthy and fibrotic lung tissue. Bulk hydrogels (500 um thick) are fabricated using UV crosslinking, and 10 um thick collagen patterns are added using multiphoton-excited photochemistry. Both normal human lung fibroblasts and IPF fibroblasts are cultured on these patterned hydrogels. The fibrillar patterns provide physical cues that influence cell motility, gene expression, and resultant cell signaling. Bulk RNA sequencing is then performed, followed by differential gene expression analysis to identify which genes are active. Finally, gene ontology and gene set enrichment analysis (GSEA) are conducted to identify enriched signaling pathways. This approach allows us to investigate how mechanical cues influence the activation of disease pathways in IPF, potentially leading to the development of new treatment strategies.

Sickle cell disease is characterized by the polymerization of hemoglobin S under low oxygen conditions, leading to red blood cell deformation and vaso-occlusion. While prior studies have demonstrated heterogeneity in polymerization across oxygen tensions and between patients, the role of red blood cell density, a proxy for intracellular protein concentration and cell age, in influencing polymerization behavior remains poorly understood. Given that hemoglobin S polymerization is concentration-dependent, it was expected that red blood cell subpopulations separated by density will exhibit distinct single-cell polymerization profiles at the same oxygen tensions. In this study, red blood cell density fractions were isolated using continuous and discontinuous Percoll gradients. Each fraction was flowed through a microfluidic device while being exposed to seven controlled oxygen tensions. Quantitative absorption cytometry was used to measure single-cell oxygen saturation, mean corpuscular volume, and hemoglobin mass per cell. Polymerized and soluble cell fractions were quantified using a previously validated image classification algorithm based on the ResNet-50 convolutional neural network. Preliminary findings reveal significant differences in polymerized cell fraction and oxygen saturation between density fractions, particularly at hypoxic conditions, suggesting that cell density is a key contributor to polymerization. These results highlight an underexplored factor of heterogeneity in sickle cell disease and suggest that polymerization may not be uniform across red blood cell populations.

Hypermobile Ehlers-Danlos syndrome (hEDS) is one of 13 presentations of EDS. It is a common heritable condition with an estimated prevalence of approximately 1 in 10,000 people and functions by disruption of collagen physiology. The standard for diagnosing patients with EDS is currently gene sequencing which is expensive and often not covered by insurance. The hypermobile variant is currently the only EDS presentation without a known genetic cause, and thus no concrete diagnosis method for this condition exists. Since collagen is a key component of connective tissue, many organ systems can be affected. This results in a wide variety of symptoms ranging from hypermobility to neurological conditions and heart defects. Recently a family of serine proteases, the kallikreins have been implicated in influencing collagen structure. We aim to develop an affordable diagnostic tool to diagnose patients with symptoms of hEDS based on gel analysis of collagen fibrils. To assess collagen structure, we will treat mammalian cells with recombinant kallikrein proteins derived from patients with hEDS. We hypothesize treatment with these recombinant proteins will disrupt normal collagen structure through incomplete fibril formation, suggesting that mutations in kallikrein proteins are causal for collagen malformation and are ultimately the cause of hEDS.

Objectively measuring tobacco smoke exposure (TSE) using biospecimens is important for confirming the effectiveness of behavioral interventions aimed at reducing TSE. However, there is limited knowledge about how certain populations perceive the use of biomarker specimens in research and the facilitators and barriers to collecting biomarker specimens in these groups, especially among U.S. African immigrant populations. The purpose of this study is to 1) determine the acceptability and feasibility of collecting salivary cotinine biomarker specimens from Somali families as part of a behavioral intervention study to reduce household TSE and 2) to identify and characterize the facilitators and barriers to participation in salivary cotinine biomarker specimen collection for Somali families. Data includes 10 key informant interviews and 6 focus groups (n=40) with Somali parents on their perceptions of TSE biomarkers and possible facilitators and barriers to collecting biomarkers. 15 Somali American families will additionally be chosen to participate in interviews as part of a broader household TSE reduction intervention about the acceptability and feasibility of collecting salivary biomarker specimens, and the facilitators and barriers of collecting salivary biomarker specimens. We will also be measuring participation levels in the biospecimen sample collection to gauge the feasibility of collecting salivary cotinine samples in future studies. Understanding how biomarker specimens are accepted within a community is essential. A clearer understanding of the perceptions of biospecimen testing will guide more inclusive future research strategies for communities underrepresented in research.