University of Michigan
Barrett, Crisha Brooks.
STRA6 is Differentially Expressed by Human PBMC Subsets.
Degree: MS, Biology, 2019, University of Michigan
Stimulated by retinoic acid 6 (STRA6) was the first protein to be identified in a novel category of proteins, cytokine signaling transporters, due to its ability to function as both a cell surface receptor and a membrane protein that binds to retinol binding protein facilitating cellular uptake of retinol. Retinol is metabolized to all-trans retinoic acid which functions as a steroid hormone transcription factor ligand to regulate genes generally involved in cellular differentiation. The role of vitamin A, as all-trans retinoic acid, in immunity is well characterized, but the role of STRA6 in mediating cellular uptake of vitamin A in immune cells is not understood. The objective of this research was to characterize the expression of STRA6 on human peripheral blood mononuclear cell (PBMC) subsets. We hypothesized STRA6 would be expressed by all PBMC subsets, but at different intensities. We also hypothesized STRA6 would be co-localized with the lipid raft. A convenience sample of volunteers were recruited and PBMC were isolated by density gradient centrifugation. Multicolor flow cytometry was used to identify PBMC subsets and expression of STRA6. Confocal microscopy was used to determine cellular location and lipid raft association of STRA6 on cell lines and isolated PBMC. All T cell, natural killer cell, monocyte, and dendritic cell subsets analyzed expressed STRA6. Median fluorescence intensity of STRA6 was higher on pDC dendritic cells compared to mDC2 and mDC1 dendritic cells, cytotoxic T lymphocytes compared to T helper lymphocytes, intermediate compared to nonclassical and classical monocytes, and cytokine natural killer cells compared to both cytotoxic and CD56-/CD16 dim natural killer cells. Age was the best predictive factor for STRA6 expression. Confocal microscopy showed STRA6 was not associated with GM1 cholera toxin subunit B staining and therefore not associated with lipid raft structures. These results provide preliminary data in which to target vitamin A signaling, through cellular uptake of retinol, in immune cells to improve immune homeostasis in diverse populations. With further research and development, STRA6 signaling in immune cells may be a therapeutic target for immune mediated diseases.
Advisors/Committee Members: Duriancik, David M. (advisor), Singer, Kanakadurga (committee member), Sucic, Joseph (committee member).
Subjects/Keywords: confocal microscopy; flow cytometry; peripheral blood mononuclear cell; retinol binding protein; stimulated by retinoid acid 6; vitamin A; Immunology; Nutrition; Biology
to Zotero / EndNote / Reference
APA (6th Edition):
Barrett, C. B. (2019). STRA6 is Differentially Expressed by Human PBMC Subsets. (Masters Thesis). University of Michigan. Retrieved from http://hdl.handle.net/2027.42/150188
Chicago Manual of Style (16th Edition):
Barrett, Crisha Brooks. “STRA6 is Differentially Expressed by Human PBMC Subsets.” 2019. Masters Thesis, University of Michigan. Accessed August 24, 2019.
MLA Handbook (7th Edition):
Barrett, Crisha Brooks. “STRA6 is Differentially Expressed by Human PBMC Subsets.” 2019. Web. 24 Aug 2019.
Barrett CB. STRA6 is Differentially Expressed by Human PBMC Subsets. [Internet] [Masters thesis]. University of Michigan; 2019. [cited 2019 Aug 24].
Available from: http://hdl.handle.net/2027.42/150188.
Council of Science Editors:
Barrett CB. STRA6 is Differentially Expressed by Human PBMC Subsets. [Masters Thesis]. University of Michigan; 2019. Available from: http://hdl.handle.net/2027.42/150188