Effect of homeostatic proliferation on the memory quality of memory precursor, memory, and naive CD8+ T cells

Open Access
- Author:
- Yuzefpolskiy, Yeugeniy
- Area of Honors:
- Immunology and Infectious Disease
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Dr. Vandana Kalia, Thesis Supervisor
James Endres Howell, Thesis Honors Advisor
Dr. Teh-hui Kao, Faculty Reader - Keywords:
- Homeostatic proliferation
memory cd8
T cells
CD8+ - Abstract:
- Homeostatic proliferation is the mechanism by which cells like CD8+ memory T Cells keep their numbers constant during the life of the organism. However, recent experiments have shown that homeostatic proliferation driven by an irradiated environment leads adoptively transferred naïve CD8+ T cells to generating memory like properties, regardless of the epitope for which the cell is specific. This inspired the question of what effect an irradiated environment had on adoptively transferred CD8+ T cells, which were 15 days into an LCMV infection, and on CD8+ memory T cells. The results of the experiment suggest that the transfer of day 15 post infection cells into an irradiated environment led to an increase of KLRG-1 and drop in markers CD127 and CD62L when compared to untransferred cells. This corresponds to increase of terminal effector cells and decrease of memory precursors. On the other hand naïve cells were not greatly affected by the transfer, as their levels of all three markers remained constant. This suggests that an irradiated environment has a negative effect on antigen experienced CD8+ T cells. One possible explanation to this phenomena is that antigen experienced CD8+ T cells have gone through many rounds of proliferation during the initial infections and that the homeostatic proliferation occurring in an irradiated environment is too demanding, leading to poor quality cells arising from the transfer. Further studies would be aimed at actual ability of these different CD8+ T cells to control an infection to see if transfer into an irradiated environment has affected the action ability and not just the apparent ability to control infection.