[CCoE Notice] BIOE PhD Dissertation Defense

[Knudsen, Rachel W]

[cid:a1f2fef9-68ae-4659-af60-6ff3e9daa3ca]


Tuesday, December 3rd, 2019 10:00 AM

SCIENCE AND ENGINEERING CLASSROOM (SEC) ROOM 204


[cid:e8c5dc25-448f-49d7-ad56-2c2c041eeb2a]

Thao Nguyen

PhD Dissertation Defense

Dr. Chandra Mohan, Faculty Advisor


“3D-Splenoid Cultures for the Expansion of Activated Pro-Inflammatory Double- Negative T-Cells.”
“Epigallocatechin-3-Gallate Suppresses Neutrophil Migration and Inflammation in Transgenic Zebrafish Model.”


Abstract

Two-dimensional (2D) cell cultures and rodent models have been used for studying immune biology; however, 2D cultured cells are often oversimplified and rodent models are expensive for these purposes. More recently, three-dimensional (3D) cell cultures and transgenic zebrafish have been engineered to reasonably replicate physiological responses. In this dissertation, we explored the utility of a 3D splenoid culture and an inflammatory zebrafish model to study immune response.

First, a decellularized spleen, called a 3D splenoid, was developed for 3D immune cell culture, in vitro. The 3D splenoid cultures yielded more viable immune cells (p < 0.01) and higher levels of cytokines, including interleukin (IL)-6 (p < 0.05) and tumor necrosis factor (TNF)α (p < 0.01), than 2D cultures. Naïve CD4+ and CD8+ T-cells (CD62L+CD44-) expanded in 3D cultures but did not expand in 2D cultures (p < 0.001). 3D cultures also promoted double-negative (DN) T-cell expansion (p < 0.01), denoted as TCRαβ+CD3+CD4-CD8-CD69+. During culture in 3D splenoid scaffolds, these DN T-cells were found to be derived from existing CD4+ and CD8+ T-cells. In sum, we report a novel 3D splenoid platform for the effective growth and expansion of transplantable T-cells, in vitro.

Second, Tg(mpx:gfp) transgenic zebrafish were used, bearing green fluorescent protein (GFP)- tagged neutrophils, to assess the impact of epigallocatechin-3-gallate (EGCG), the primary catechin found in green tea. Here, based on in vivo fluorescence imaging, in vivo accumulation of neutrophils was found to be elevated after tail resection, which was effectively reversed by treatment with 300 µM EGCG (p < 0.05). Under the influence of EGCG, inflammatory neutrophils were less activated, as indicated by the lower speed (p < 0.01) and travel distance (p < 0.001) compared with the non-treated group. We explored the mechanism underlying EGCG action, revealing that the expression of signature genes associated with IL-1β, TNFα, and related signaling pathways was downregulated after EGCG treatment. Taken together, these results demonstrate the convenience, transparency, and simplicity of the zebrafish model, which facilitates the tracking of fluorescent neutrophils in real-time, allowing inflammation to be monitored and the impact of therapeutic agents to be readily assessed.

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://Bug.EGR.UH.EDU/pipermail/engi-dist/attachments/20191125/bd06dd72/attachment-0001.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Outlook-r22dwion.png
Type: image/png
Size: 56601 bytes
Desc: Outlook-r22dwion.png
Url : http://Bug.EGR.UH.EDU/pipermail/engi-dist/attachments/20191125/bd06dd72/attachment-0002.png 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Outlook-irth13vs.png
Type: image/png
Size: 80787 bytes
Desc: Outlook-irth13vs.png
Url : http://Bug.EGR.UH.EDU/pipermail/engi-dist/attachments/20191125/bd06dd72/attachment-0003.png